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MG TD TF 1500 - Help! Setting Float Height on S.U. Carbs - MG TD
| OK, I've been working with S.U. carbs since I was a teenager, but this one has me stumped. I've read Dave Braun's extremely helpful and detailed "S.U. Carburetor Tuning" (http://www.dbraun99.com/Setting_SU_Carburetors%C2%AD_Rev_C.pdf) and I'm really having trouble setting those floats to read the proper height of fuel at the jet. I've checked the floats to see if they've got fuel in them and they're OK... they've been shaken (not stirred) and there's no sloshy stuff inside. I switched on the car, allowed the bowls to fill and then checked the height of fuel at the jets... well, I could not see any fuel at all, even with the jet pulled fully down on the choke. Dave's excellent step-by-step PDF says that the fuel should be at 0.160" +/- 0.040" and not to worry if the lever needs to be bent drastically different from what it says in the manual. So, I dutifully tweaked the lever and kept checking, each time draining the bowl with a syringe and letting it refill, trying to get the fuel to rise up where I could see it. I kept bending that lever up until it was virtually flat(!) and the best I could do is with the choke pulled fully down I can just now see the fuel at the jet (see photo). Measured, this comes out to 0.334" (see next photo). Clearly this is slightly off from Dave's figures, and there's really no further I can go in bending that dang arm. I'm at a loss here. I checked the gaskets and as you can see from the photos there's nothing really odd here - they're not overly thick or thin. Also, I installed the fill-valve with a single paper washer that comes in the kit, so it's not excessively high. Any thoughts on how to get that fuel level up to where Dave says it should be? I know this had got be something I'm missing here!  |
| Kevin McLemore |
| More pictures... Choke fully down. You can just see the fuel near the orifice.  |
| Kevin McLemore |
Here's a photo of me measuring the height with the choke fully down and the fuel level as you saw in the photo above. Note the 0.330" depth. |
| Kevin McLemore |
Finally, here's a photo of under the carb, showing the stacked height of the bowl - nothing's odd there, I don't think.  |
| Kevin McLemore |
| More details pretty please. Was it running reliably and just crapped out? Has it been sitting 50 years? Is it fresh overhaul and this is just maintenance? New rebuild parts? Thoughts come to mind like wrong float needle- too long. One thing I noticed- when I tweak float levers, the lever and needle wind up perpendicular, not on an angle as yours appears. That could be a clue that the needle is protruding farther than normal. |
| JRN JIM |
| Thanks for your response... let me give you more info: -- "Was it running reliably and just crapped out?" Yes, it was running and driveable, but I've not been able to get the carbs to tune in the fuel mixture properly... idle was not smooth and I could hear puffing and popping at the tailpipe, as you'd expect with a car out of tune. I did balance the carbs' airflows with a UniSyn and I started my tuning (before reading Dave's PDF) with jets at 6 flats down (although after reading Dave's PDF I probably should have started at 9.) -- "Has it been sitting 50 years?" Well, not 50, but certainly 15 or more. I resurrected the car out of a fellow's garage. He said it never ran right (there should have been a clue!). -- "Is it fresh overhaul and this is just maintenance?" Completely refreshed carbs... cleaned them thoroughly, checked for bad shafts (OK) and all the new parts are from a kit supplied by Moss in an 'official' blue S.U. box. I even checked the top jet washer they supplied to ensure it was the thinner one and not one of those incorrect fat ones (it was the thinner one thankfully). I also measured the new jets to ensure they were definitely 0.090". -- "New rebuild parts?" See above. -- "Thoughts come to mind like wrong float needle- too long." Yeah, I thought that, but have a look at the photo - it's about the same length as any others I've seen and doesn't rise to such a height as to be a problem. -- "One thing I noticed- when I tweak float levers, the lever and needle wind up perpendicular, not on an angle as yours appears. That could be a clue that the needle is protruding farther than normal." Actually, in that photo I couldn't twist the cap far enough to go upside down (the hose banjos were still connected), so the jet plunger has dropped just a bit, as well as the lever. It does lay dead level without depressing the jet valve's spring. I should also note that before attempting tuning I also went over the motor and did basically everything you'd want to do to an engine before starting it after sitting for 15+ years... static-adjusted the timing for 8 degrees BTDC, cleaned and gapped the plugs, checked compression, checked and adjusted the breaker points, adjusted the valve clearances, change the oil and filtre and coolant, etc. The car ran OK and performed reasonably well, but I just have not been able to get the engine to idle nice and smoothly. =================================================== I should note that this isn't my first rodeo... I have had over 43 British cars over the years and done virtually all the work on all of them... currently I have a 1949 Triumph Renown, 1967 Morris Traveler and 1967 Sunbeam Alpine (in addition to this 52 TD), but over the years I've had 13 Sprigets, a Morris Mini Minor, A40 Farina, Sabra Sport, Swallow Doretti, Triumph 2000 MKI, Turner 950S, Elva Courier and 2 Spitfires. At least those are the ones I remember... after all, I'm 58 now and it's been a few years. :) Photos of my new-to-me MG, now finally cleaned up and on the road: http://img.photobucket.com/albums/v296/procolharum/52%20MGTD/B915F43F-C4BF-4BFC-9759-969E5968058B.jpg http://img.photobucket.com/albums/v296/procolharum/52%20MGTD/80560CC0-E584-4B44-8EE8-C59EA86901C9.jpg |
| Kevin McLemore |
| Sorry, those Photobucket links above probably don't work... let's try these links: http://oi59.tinypic.com/fbjr4p.jpg http://oi62.tinypic.com/2q1zd4g.jpg |
| Kevin McLemore |
| You should be checking the fuel level with the choke level fully relaxed (up) not fully down, as that is the position it should be in when driving. Since the jet will displace fuel in the carb, letting the choke fully relax should raise the fuel level considerably. Also, ensure the floats are not leaking. If they take on fuel, they will also alter the correct fuel level (although in the opposite direction). |
| Lew Palmer |
| It appears to be a spring loaded needle. My recollection is the SUs are solid. If Moss distributes them, you'd expect they'll do the job. As long as it is the same length, it ought not matter. Replace the dual carbs with a supercharger so there's only one SU to adjust! Tom Lange will agree! (just kidding) |
| JRN JIM |
| Thanks, Lew. I did check the level initially with the choke fully in (i.e. not on)... no gas level was evident at all. As I noted, in order to see any fuel I had to adjust the float lever fully up (virtually flat) and even then to see the fuel I had to pull the jet down (using the choke, instead of disconnecting all the linkage underneath). It seemed to me that pulling the choke or going to the trouble to actually disconnect everything and pull the jet down by hand wouldn't make much difference... either way the only thing that happens is that it moves the jet down. No? |
| Kevin McLemore |
| Oh, and as noted, I did check the floats... shook them and listened... they have no gas in them and appear to be OK. |
| Kevin McLemore |
| As to the blower, Jim, funny you should mention... I happen to have a brand new Judson on my Morris Minor... and no SU Carb at all - it's the original Judson-equipped Holley. :) |
| Kevin McLemore |
| Hi Kevin, First of all, nice car, and good pictures. Lew is correct that the float level will vary when you pull down the jet on enrichment. But not considerably, except by capillary action. The method of pulling down the jet is for a base measurement for the butt end of the caliper, as you are attempting. Can you see the fuel in the jet without lowering them? When you drop the jet, it will pull the fuel down because of capillary action and because it represents a very small orifice to rebalance the fuel levels. So, when you pull down the jet, see if tapping on the side of the bowl will get the fuel levels to equalize, or play with the jet height a bit to see if you can get the fuel to stabilize at a natural point. Also, the lid has to be on the float bowl when performing the measurement, as the float should be held down and displace the top of the fuel level, making it higher than with the float removed. It appears that you have everything else correct, but of course the bowls do have to vent so pressure on the surface of the fuel in the bowl can push down on the fuel and drive it up into the jet. That process is from the overflow vent tubes, and the solid aluminum washer must be under the female bolt head, while the segmented washer must be between the banjo and the float lid. The larger opening in the banjo must be toward the float lid also. Do you have tickler pins on the float lids? I didn't see any, and with the fork that flat I should think they would foul the float before the needle shut off. The spring loaded needle is fine. If you placed washers under the needle housing, remove them. Also, your floats are probably new, correct? I wonder how much they weigh? The lighter they are, the higher they float relative to the surface, and the sooner they shut off the fuel, leaving it low. The float lid looks to be in the right position, because the higher they are, the more they foul the suction chamber cheese head screw. I use a baby's suction bulb to take fuel out of the float bowls and I put it in a container to dump back in the tank. Then I let the pump fill the float bowls. Make sure the vents are clear. As I said, try varying the level of the jet to get a feel for how much the jet pulls the fuel level around. I hope this information helps. If you have something work better for you, let us know. I would not mind rewriting that portion of the instructions as you are not the first to have trouble with lowering the jet to see the fuel level. Warmly, dave |
| Kevin McLemore |
| I'm with you, Kevin. I've never been able to make that measurement. But then, I use Grose Jets. Bud |
| Bud Krueger |
| Kevin - I jumped through the same hoops as you trying to get the fuel level at 0.16" below the bridge of the throttle bodies in my TF-1500. Never did get the level anywhere near 0.16". My float forks were also nearly flat. I finally gave up. I set my floats at a fat 7/16" and didn't even attempt to look at the level in the bridge. To tell the truth, I can't tell any big difference. Carbs idle best with jet adjusting nuts three flats down, same as before. Idle is a little better (?), but still rough. The engine sounds like a symphony above 1800 RPM ... better than it ever has. Doesn't starve for fuel at speed. 'Course I have adjusted everything to specs and replaced everything else, including the head. Lonnie TF7211 |
| LM Cook |
| You should be checking the fuel level with the choke level fully relaxed (up) not fully down, as that is the position it should be in when driving. Since the jet will displace fuel in the carb, letting the choke fully relax should raise the fuel level considerably. Also, ensure the floats are not leaking. If they take on fuel, they will also alter the correct fuel level. |
| Lew Palmer |
| Lew, I don't agree about the choke position...but perhaps I am missing something. As I see it, the fuel will seek it's own level below the bridge to match it's level in the float bowl. As long as the choke is not moved around as the float bowls fill I fail to see how it's position will effect the actual level of the fuel. Perhaps if you leave the chokes up you will have capillary action that will effect your view of the measurement...but otherwise fluid will seek it's own level no matter what mass is put in place as long as the balance passage is not completely blocked. What did I miss? Regards, tom |
| tm peterson |
| I'm with Tom. Pull the main jets down and then fire up the pump. The fuel will rise to the same level, jets up or down, but it is easier to measure with the main jets down out of the way. |
| JRN JIM |
| OK, in an attempt to get to the bottom of this (or, at least to get the fuel to the top of the jet), I'll try my best to answer Dave's questions & comments: -- Lew is correct that the float level will vary when you pull down the jet on enrichment. But not considerably, except by capillary action. Right, I agree - as noted by others, the fuel is not very viscous so it will readily find its own level fairly rapidly. In fact, to test that, once you see the fuel in the jet (as in the photo I posted earlier) you can gently blow on the jet and you'll see that even with your gentle blowing you can make the fuel level go down slightly... and when you stop it will then pop right back up to where it was originally. So, I think that's proving to me, at least, that the fuel is easily seeing its own static level (i.e. "equalize", as Dave stated it). -- Can you see the fuel in the jet without lowering them? Not very well when the jet if fully at the top, no... but then I'm 58 and my eyes ain't what they used to be. I imagine with a very bright lamp shining down there you might be able to, but it's definitely down there. -- ...see if tapping on the side of the bowl will get the fuel levels to equalize, or play with the jet height a bit to see if you can get the fuel to stabilize at a natural point. As noted, it does seem to equalize, but just not high enough. It consistently equalizes at the 0.334" height with the lever virtually flat. -- Also, the lid has to be on the float bowl when performing the measurement, as the float should be held down and displace the top of the fuel level, making it higher than with the float removed. Yep, agree. I held the top firmly on the bowl with my hand and could see that was important to making it all work properly. I did install the nut on top just to see if that made any difference but it didn't - holding it down was as good as using the nut. The measurements I made were with the nut and washers installed. -- ...of course the bowls do have to vent so pressure on the surface of the fuel in the bowl can push down on the fuel and drive it up into the jet. That process is from the overflow vent tubes, and the solid aluminum washer must be under the female bolt head, while the segmented washer must be between the banjo and the float lid. The larger opening in the banjo must be toward the float lid also. Yep... I've done SU's many hundreds of times over the years, so I do know the alloy washer goes just under the nut and the slotted fiber washer goes under the banjo, allowing the pressure to vent into the banjo housing. And the vent tube only goes on one way, given the original (an unaltered) bend in the vent tube. -- Do you have tickler pins on the float lids? I didn't see any, and with the fork that flat I should think they would foul the float before the needle shut off. No, and I also don't have a lift pin to raise the primary valve body piston, either. To test mixture I need to use a small rod or screwdriver to lift the piston the requisite 1/32". These are pretty early S.U.'s I'm guessing. -- The spring loaded needle is fine. If you placed washers under the needle housing, remove them. Will try that tomorrow, but it's really not a very thick washer in the first place. That being said, I thought the needle valves always had a small washer to prevent valve thread leakage under pressure and subsequent overflow of the bowls? -- Also, your floats are probably new, correct? I wonder how much they weigh? The lighter they are, the higher they float relative to the surface, and the sooner they shut off the fuel, leaving it low. Floats are the original brass ones and I will try and weigh them tomorrow on a gram scale. I agree about the lighter bit. They don't appear to have been fiddled with (i.e. not been resoldered and hence become heavier). -- The float lid looks to be in the right position, because the higher they are, the more they foul the suction chamber cheese head screw. Yep. I have to tilt the lid slightly to remove it, but it comes off easily. -- I use a baby's suction bulb to take fuel out of the float bowls and I put it in a container to dump back in the tank. Then I let the pump fill the float bowls. Yep, that's the exact procedure I used, though I used a larger battery-filler bulb to remove the fuel and dump it in a small container. Sucks out the whole bowl in one go! -- Make sure the vents are clear. Yep, they are. I even tried leaving the nut off and running a small rod down the vent in the cap to press down the float whilst I held the lid down firmly... when I pushed the rod down gently the fuel level would rise in the jet, as expected, due the the float's displacement of the petrol. -- As I said, try varying the level of the jet to get a feel for how much the jet pulls the fuel level around. Doesn't seem to make any difference. The level remains the same no matter how high up or down you move the jet. Again, blowing lightly on the jet pushes the fuel down and it flows right back up when you stop blowing... moves quite easily and consistently returns to the same spot. ============================================= Thanks to everyone for their input, particularly Dave. I'm still still stumped, but at least I know I'm not the only one! :) Cheers, Kevin |
| Kevin McLemore |
| I noticed the fork appears like it could be installed upside and then was bent to compensate. Maybe the doings of the previous owner and why he couldn't tune it up. Again, that is the one photo that shows needle on an angle. |
| JRN JIM |
| OK, so here's some more data (but be sure to read my answers to Dave's comments & questions above first). Fuel valve overall length with plunger installed and spring uncompressed: 0.758" Thickness of paper washer under fuel valve: 0.015" Jim, to answer your question, the lever is not upside down, but may be different from those you've seen before. There appears to be two different arms supplied for these carburetors, and I will post a photo of both below. The first, which was found in the carburetor when I took it apart (and which I am using and has been seen in the previous photos - it's chrome) appears to have the fixing pin "in line" with the lever's center. The second type, which came in the S.U. repair kit (copper colored) has bent arms which hold the fixing pin above the center line of the arm (and therefore the contact point for the valve is lower). This, obviously, will significantly impact the height of the fuel in the jet, which is why I used the original ones. Thanks, again to all of you for your attention and help in sorting this! Cheers, Kevin  |
| Kevin McLemore |
| By the way, I'll attach photos of a few useful tools for working on S.U. (and Zenith-Stromberg) carburetors. The first is a thing called a JetSetter and has been with me since god-knows-when. It's extremely handy for quickly setting up the jets to be exactly equal and for determining jet height measurement, though certainly you can use a caliper as seen earlier and as Dave describes in his PDF. The second is a float lifting pin. I think I made this tool many years ago, so you can easily make one like it, but it makes getting those bobbing brass floats out of the bowls a cinch.  |
| Kevin McLemore |
JetSetter in use.
 |
| Kevin McLemore |
Float lifter tool in use.
 |
| Kevin McLemore |
| Oh, and Dave, the brass floats weigh exactly 21 grams. |
| Kevin McLemore |
| Hi Kevin - In looking at your second "JetSetter" photo, it seems as if your throttle shaft actuating lever arm is set way too high - the arm should point in a downward direction even when at full throttle - The picture makes it look as if it is up too high - almost hitting your carb body. I know this is not related to the mixture setting - but I just noticed the photo. Best regards |
| DLD |
| Greetings from Australia Kevin, All the advice given is very sound and I really can't offer much more, BUT, I think you might have inherited a problem with the car created a long time ago by a PO/mechanic. The fuel level in the jet and bowl is a simple syphon, so in my mind the only way to fix your problem is to lift the float bowl in relation to the carb body. Looking at your photos, the float bowl collar that attaches to the body looks thicker than the ones on my cars (Y-Types). Do you think that you might have a pair of bowls that are not "matching" the carb body with a thicker mounting flange ?. This would lower the float bowl & fuel level and explain why you cannot adjust the float lever enough to compensate. What is the part number on your float bowls - usually cast on the side ?. Could be worth comparing with the numbers on other peoples bowls. SU made hundreds of different bodies and bowls over time - I think you have a mis-match problem. You are a very experienced person with SU's, so I'm sure your problem is not one of adjustment or application, so you need to go to first principles and take nothing for granted and check all the major components are matched. Good Luck Tony The Classic Workshop |
| A L SLATTERY |
| Thanks, Tony and DLD. DL, as to your comment on the throttle arm, I can see what you're seeing and it does look too high. That being said, I think it's a bit of an optical illusion given the angle the photo was taken. The arm is, in actuality, quite far from the carb body and pointed down a fair bit. And Tony, greetings from the Cradle of Liberty, Philadelphia! As to the possibility of there being a DPO who should never have been handed a spanner, yes, this car definitely had at least one of those owners, and perhaps more. For example, when he re-trimmed the interior he simply forgot to put in a box for the side curtains... he just trimmed up a back panel in tan leatherette and left the hole in the boot floor, covered by carpet. (sigh) And when he cut the floor boards he made an error and left a gaping hole to the right of the transmission tunnel and... you guessed it... covered it with carpet. He's also painted the side panels on the fuel tank and the brakes were a bloody horror show... he had used the handbrake adjuster to 'adjust' the rear brakes.... and in fact he had adjusted them so far that they were in serious danger of blowing out all their fluid! The final straw on the bakes was when I found he'd installed the front hoses in a manner that they badly rubbed against the damper arms and one had worn well down through 2 layers of cord - one more layer of rubber and there would have gone the brakes. As to the potential thickness of the bowl base, yes, I suppose that's a possibility. Do you have a measurement for the thickness of yours so I can compare? My other thought was that the bowls may be too tall... the lids nearly impinge on the valve body and have to be tilted to be removed... I do wonder if perhaps there were shorter bowls originally? If so, the lever arm and valve would be lower, raising the fuel level in the jet. Thanks to all for your superb help on this! |
| Kevin McLemore |
| Kevin, One of your pictures gives the solution to your problem. I have copied it below. If you look at the two forks, you will notice that the position of the arm relative to the pivot is different. The original design has the arm offset by about 1/8 of an inch, the more recent design has the arm on the centre line of the pivot. it is this offset which enables you to obtain the correct curve on the fork. John  |
| J Scragg |
| John S, Kevin spoke about the different levers in an earlier posting and is using the silver ones which will assist his issue - the brass coloured one will make it worse. Kevin, I would if I could but I have just moved house and all my spare carb parts are packed away in storage, and even the Y-Types are 2 hours away from home until my new garage is built. Over to anyone else out there willing to help sort this little mystery ?. Somewhere in my files are some calculations I did on the specific gravity of 1950 fuel compared to todays brew - there was quite a difference - and this means the floats "float higher", therefore pushing down the fuel level - just like your problem. I'm testing my memory, but I think 1950 fuel was around 580grams per litre, while modern fuel is around 720 - now don't quote me - check for yourself. Now if the floats are 21 grams (in 1950 and now), we are able to calculate the different float heights. Any retired marine engineers out there ?. I'm going for a sleep before doing the calculations - (and checking those SG numbers). Cheers Tony The Classic Workshop |
| A L SLATTERY |
| Tony, Could it be that "down under" the basic rules of geometry are also upside down. John |
| J Scragg |
| Yes, John, as Tony noted I am indeed using the silver 'in-line' levers and not the copper 'offset' levers that came in the kit. But you're right, using those copper levers would indeed cause the level to drop even further than it is. Dave (if you're still tracking this thread) I wonder if Tony is right about the fuel's specific gravity? Given you're probably using current fuel to test the carbs you rebuild before sending them on their way, what measurements are you currently getting? |
| Kevin McLemore |
Hi Kevin. I think you are going in the wrong direction.By flatting the silver lever you are causing the fuel level to drop. I think that by using the copper lever it will push the float down displacing fuel causing the fuel to rise in the jet.Think of when you hop in a bath.you fill the bath to a certain level then hop in and the water level rises.Anyway it won't hurt to try the copper lever and see what happens. hope this helps. regards Ralph TF 9181 |
| R E J Stewart |
| ralph, the bath tub analogy is a false equivalency..in that the float does not push down into the fuel raising the fuel level..the float sits on top of the fuel and as the fuel pump delivers fuel into the float bowl the float rises and shuts the flow off at the LOWER level. regards, tom |
| tm peterson |
| If it were my TD, I'd yank those pins off the bottom of the needles and get to work adjusting the fuel elevation. SU float needles were, and are still available solid. Don't care for that idea? Add some weight to the floats. Adding a few extra psi air to the tires will raise the fuel level, too! More than one way to skin a cat. Have you tried giving Joe Curto a jingle? |
| JRN JIM |
| All, As this thread is long and verbose, for the sake of clarity, I will be brief. The statement from Tony S. "Kevin spoke about the different levers in an earlier posting and is using the silver ones which will assist his issue - the brass coloured one will make it worse." is INCORRECT The statement from Kevin " using those copper levers would indeed cause the level to drop even further than it is". is INCORRECT. Using the copper plated (Offset) levers WILL solve your issue. This, I mentioned in my initial reply John |
| J Scragg |
| I'll go ahead and stick my nose into this "T" business. I think J Scragg may be right. At first glance it seems it pushes the fork deeper into the chamber, which would make it worse. But note how much farther the contact point of the arm will be from the end of the float valve. This would have the same effect as having a shorter valve, which will raise the fuel level. Charley |
| C R Huff |
| By the way, if anyone wants one of those "Jetsetter" devices which I showed in my previous photos in this thread, there's one up for sale presently on eBay (expires tomorrow, I think). It is a very handy device for setting up initial jet heights and ensuring they match. It's being sold along with a Uni-Syn like device made by Moto-Meter (also a very useful tool). http://www.ebay.com/itm/221589368546 |
| Kevin McLemore |
| I had exactly the same problem on my 1933 MG M Type. This had a single bronze bodied SU with a monkey metal, bottom fill float chamber. These float chambers are very prone to cracking and are virtually unobtainable so must be replaced with a "modern" top fill, SU version - similar to a T Type. I read in Dave Braun's article how to set the fuel hight but no matter how much fiddling I did with the float fork I simply couldn't get the level ocorrect. I know this won't be a solution for a T Type with original SU components but I took the lid off the float chamber and and measured how much clearance there would be if the fork was straight and the valve was shut off. I then carefully filled the float chamber with white spirt until the float was at the point I had measured. I then lowered the jet until the miniscus was at the fluid level. It was much too low and there was no way of raising it since the fork was straight. Because I was using non standard components I had to machine material off the carb body and float chamber spigot to raise the fuel level. Even though not a solution for a T Type the tips I would give are:- 1) Use the above method to ensure that with your existing float chamber it actually possible to get the correct fuel hight. 2) You can check the fuel hight in the jet tube by lowering the the jet until the meniscus is just at the top of the jet - determine this by wiping the top of the jet with a piece of a paper tissue. A damp patch will be clearly visible. You can measure the depth of the jet with a vernier caliper against the bridge. 3) Don't use petrol - I initially did and the garage, the house, my clothes and me reeked of it for days. I used white spirt, don't know about the viscosities but it worked for me. Good luck Jan T |
| J Targosz |
| J SCragg has the correct answer. Use the copper colored one and it will allow higher float valve settings. I have been working with these type carburettors since 1948 and have seen many strange parts in use.Are you certain that these float bodies are the correct ones? Even the thickness of the gasket used on the float cover comes into play as do the seal rings on the upper contact area of float body to carburettor. Sandy |
| 3:0:5^110:0:5^127:0:2 |
Jan and "3:0:5^110:0:5^127:0:2, default, threadlist", we all three got sucked in by the same thing - this is a reativated thread from back in the summer. Hopefully by now Kevin has his problem sorted out. Nonetheless, since I dashed off to look at my float levers I'll post this anyway. I think the drawing on page B11 of the WSM supports J Scragg that the copper colored lever is the one to use. Jud
 |
| J K Chapin |
| Well, actually, I did use the copper ones but even with them I never did manage to get the fuel height to match that which was documented by Dave. That being said, I did find that I had two other problems which I was able to resolve and which greatly helped the running of my car. First, some idiot DPO had installed springs in the carbs - TD's shouldn't have them, I learned, and removed them. Second, my air valve pistons had too much clearance and failed the 'drop test'. I repaired the latter by using a light coating of high-temp paint on the rims of the pistons and then honing them to match the air chamber bells... so far that's working, but I'm watching carefully to see if it's a long-term solution. |
| Kevin McLemore |
| iI had a similar problem - couldn't for the life of me get the Dave Braun fuel level setting thing to work for me. Just couldn't see the fuel level in the jet / could only if I pulled the choke right down. Settled for going back to the stock adjustment on the forks and then ensuring that both bowls had fuel at the same level. This at least removed one variable from the later tuning. Anyway worked good enough for me. Been very happy with the performance and tuning since. Dave |
| D Moore |
| As I posted previously this link provides some useful facts; http://www.jcna.com/library/tech/tech0006.html They dont all apply to your model of SUs. Checking the fuel pump delivery pressure might be a good starting point as float height setting is not the only contributing factor. |
| G Evans |
| Kevin, I see that this thread was re-activated with the jet setter on Ebay,, I missed the thread when it was active,,, and I see that you have a RENOWN,,, PLEASE email me for our event here in CT in which the "Early Triumphs" are our featured marque in 2015 We would really like to see you attend! MGTD52 AT COMCAST DOT NET Thanks, Steve,  |
| Steve Wincze |
Thanks, Steve! I do indeed also have a Renown in my collection, but mine is not a nicely restored example... she's a 'survivor' car and has her share of bumps and bruises... not sure she's ready for such an auspicious event! Plus, although she's a pretty reliable runner, I don't think the old girl would appreciate the long drive from Phila to CT. She prefers to take leisurely drives down quiet country lanes on pleasant Sunday afternoons, with a picnic basket in her boot for her owners. :)
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| Kevin McLemore |
| Oh, and before she kills me, I should note that "the old girl" I mentioned refers to the car, not my lovely wife! |
| Kevin McLemore |
| I'll add one thing worth checking that I've posted about before: Look at the Moss carb diagram, part #33. Measure that washer. If it is more than 0.015 thickness, get a new one of the correct thickness. Many rebuild kits came with washers as thick as 0.033, which does not allow the jets to rise to their full height. You can discard it completely (I have) and it solved my carb problems. |
| Geoffrey M Baker |
| Kevin,(and lovely wife and the old girl) BBTS is actually a fun Gathering,not a stuffy “show”! Picnic, beach, mansion tours and a lot of good “natter and noggin” !! Last year we had Riley as MOTY,, 17 cars,, Two were in the very beginning of restoration, didn’t even have a motor ,, another was a totally original unrestored 1950 survivor,, Send me an email if you might be interested of know of other Early Triumph owners Go to www.CTMGCLUB.COM click on the British By The Sea tab,, scroll down and on the right side click on the Aerial Video and Pictures Steve  |
| Steve Wincze |
| BTW, Steve, that Mayflower pictured in your flyer - that doesn't happen to be the one that has the back portion covered in woven yellow/tan rattan, does it? |
| Kevin McLemore |
This thread was discussed between 23/06/2014 and 05/11/2014
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