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MG MGB Technical - SU Conversion - Where do all the extra bits go?

'77B Roadster. With many thanks to all of you folks here for your help and knowledge, I have nearly completed my SU conversion. (Tony Barnhill, I promise I will send over the ZS parts). My problem is that I have no knowledge of what to do with all of these hoses that are now just hanging around. I have two coming off the valve cover area plus a couple coming out of that "thing over on the right side of the engine compartment and one coming out of the brake assembly. After much research through the archives I have been unable to come up with the correct answer. Can anyone point me at a good explanation of how to reconnect/discard these pieces?
Next, The linkage on my carbs is old and has been "modified" over the years and I am not sure that the cable connections are original. I would like to get these to a point where the cables will connect properly. Does anyone have any good pictures of this detail or can let me know where to get these little bits. As is normal in many jobs like this it's the tiny details that hold you up. It turns out that my most used tool has been my tap wrench. Finally, as I have been going through this conversion I have been fixing little things that have been "field modified" over the years. Could someone please let me know the correct placement of the fuel filter? I know it's not supposed to just hang in mid-air and I think that it mounts on the firewall, but how is that accomplished?

Thanks again all, for you knowledge, wit and wisdom.

Bob Anderson, Alpharetta GA
Bob Anderson

Bob

I own a '77 B that is modified to a HIF. I understand you point about field mods. My throttle cable is hooked to the linkage by a fishing snap swivel! I can tell you that the larger tube from the vacuum assist should go to a tap on the input manifold. If your mamafold does not have provisions for one, you might inquire at www.aptfast.com about their phenoloc spacers that go between the carb and the mamafold that have a port for vacuum.

Ernie
Ernie

Bob

Do you have HS or HIF carbs? This affects how the throttle and choke cables are routed.

BarryQ
73B
B.J. Quartermaine

Thanks Gents, My carbs are HIFs. The pipes that I have questions about are the one coming from the running-on valve, the one coming off the cylinder head at the rear of the engine and the one coming from the brake cylinder.
John Arthurs, the exceptional gentleman who donated the carbs and other bits has emailed me and explained about the other parts. But I really do want to find a good method of connecting the throttle and choke cables.
Ernie, that is a great piece of "creative engineering" with the fishing snap. I might just end up doing that if I can't find anything else. By vacuum assist, do you mean vacuum advance? I have that one taken care of.

Thanks again guys.
Bob.
Bob Anderson

Bob

With the HIF carbs the heatshield has integrated supports for the throttle cable (from the top) and choke cable (from below). With the choke, the inner cable is fixed in a screw clamp attached to the heatshield and the outer cover pushes against the operating lever and moves with it as the choke is engaged. I purchased a new heatshield from Moss since mine was cracked - it looks good and installed with no problem.

The following link shows my engine bay. If you look carefully you can see the green throttle cable coming in from above between the carbs and on the right of the overflow cross over pipe you can just see the free end of the choke inner cable sticking up through the clamp on the heatshield. You can also see the fuel filter - there should be a second clamp on the line forward of the filter but the bracket previously welded to the fender has disappeared.

http://home.cogeco.ca/~bquartermaine/engine/index

BarryQ
73B
B.J. Quartermaine

BarryQ -

Nice pic of your engine compartment. Is that a rubber cap on the vacuum capsule of your distributor? Are you not using vacuum advance? Greg
Greg Smela

Thank you Barry, your picture is very informative. You seem to have much more space in you engine room than I have on the '77. My problem regarding the cables is not how they are run but the actual connecting hardware for the inner cables. I have not yet found hardware that will do the job to my satisfaction. (I must admit, I do tend to over-engineer a little) I need to find some pieces that, I feel confident will not come loose at the most inopertune time (Murphy travels with me).
Thought that Ernie's idea was quite unique.
I'm thinking of mounting the fuel filter on the back firewall and securing it with a 1.5" EMT conduit clamp. I also have to secure all those hydraulic and fuel pipes at the back of the engine. Previous owneers have just left them swinging in the breeze. These are the things that tend to cause failures and it is so easy to protect against them.
Bob Anderson

Bob, the one coming off the rear of the head is a water line, formerly used for the choke on your Z-S carb. It needs to be removed and plugged.
Ken Lessig

Bob, I took some digitals today that may help. The car is a 74 so there will be some differences. To view the photos go to my Yahoo Photos link;
http://photos.yahoo.com/flash1929
Click on the HIF Carburetor Hook up album.
Photo #1 shows an overview of the linkage and brackets.
Photo #2 shows the manifold and choke and gas cable bracket. You asked about the anti run on hose, it is the hose near the front of the manifold. The choke and gas bracket is bolted to the manifold and a flange on heat shield. It does not come with the heat shield and is listed in Moss as NA, so if you don't have one you will have to fabricate one or find a used one.
Photo #3 is a closer view of the bracket. You can see the gas cable one the left going through the sleeve in the bracket. On the right the choke inner cable goes up through the bracket. Originally there was a small screw to secure the cable but they get broken so a universal cable stop works ok.
Photo #4 shows the bracket and cable relationship.
Photo #5 shows how the cables are fastened to their respective linkages. The gas cable uses Moss 375-108 Cable Stop, page 76 item 68 in catalog. You really need this part to do it right. To the right is the choke cable and it's abutment, also NA. However the HS abutment 276-055 should work ok, it's on page 76.
Photo #6 is a photo of the bracket on my spare carbs. Note the fabricated cable outer housing sleeve.
Photo #7 shows the detail of the sleeve, I made it from a brass fitting.
Photo #8 shows a choke abutment I fabricated from a bolt I had in the parts bin.
Photo #9 is a photo of the choke abutment used on HS carbs and I believe it will work ok on HIF chokes.

I didn't get a photo of the fuel filter but it attaches to the inner fender with two clamps around the hose to support it. your car may not have a place for the clamps. Sorry about this being long but I hope it helps someone, I'll try to leave the phots available depending on Yahoo. Good luck Clifton
Clifton Gordon

Clifton - nice set of pictures. Being a relative neophyte it gives me some assurance that mine is assembled correctly!

Greg - what you see on the vacuum capsule is not a plug but the back of a right angle connection running to the carb manifold.

BarryQ
73B
B.J. Quartermaine

Ken, when I removed my ZS thw water for the choke was coming from the heater line, through the choke and back into the coolant return pipe. I suppose I should practice what I preach - RTFM. I'll see what Mr. Bentley has to say about these tubes.
Clifton, Terrific pictures, thanks very much. I have saved them and will put them to use in the morning. The way that the fuel line is situated in my car seems to beg for the fuel filter to go on the back wall. I have kind of earmarked the fender to secure my new heater return hose and keep it away from the carbs.
Hell, I'm spending too much time here I'm supposed to be getting ready to go out. Thanks again guys. Come to Atlanta, The beer is on me.
Bob Anderson

Bob,
I have a '77 B and may have sent you pictures before. If not, I have lot's of the conversion to HIF4 carbs. I'll send a few to you directly, as I'm not sure I can do it through this site.
If you need any pictures of a particular area, or still have specific questions on connections, just let me know.
So far, it looks like you are getting some excellent advice, and it's fun to see some of the other engine bays.
Randy
1977 MGB
randy olson

Thanks Randy, I have all the pictures that you sent me when I started this project. Guys, if you want to see some excellent SU conversion pictures ask Randy for his. I have been using them as my main reference but a couple of areas are a little obscured. Randy,what did you do with the brake cylinder hose?
Bob Anderson

This thread was discussed between 27/02/2003 and 01/03/2003

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