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Triumph TR3 - Cold starts

Hello. I have had a seller of a Tr3 (that I wish to buy) tell me that when starting the car cold, it takes quite a few cranks to "fill the carburetor bowls" before she fires. "You're going to think it won't start," he says, "but she always does". Do SU carbs really do this? I can't find any info. in the repair manual to reflect that. Most carb's bowls remain full from previous use. I'm was thinking compression weakness and I did not have tester w/ me. I drove the car for about an hour, and she ran excellent. No lack of power,smoke or anything else. Re-started numerous times afterwards w/o any hesitation.
Any advice? Thanks, Mike Gambordella
Mike Gambordella

Mike - I once had a problem back in 1963 or '64 like this but it was in the summer. It would take a long time to start. When it did, it went perfectly. If I shut it off and left it an hour, it always restarted OK. The problem only arose after it had been parked for a long time - like overnight or longer.

There was dirt from my gas tank that got past the screen filter in the glass bowl under my fuel pump and it settled in the bottom of the float bowls. When I would try to start the TR after a long period of time, the shaking of the engine trying to start would eventually agitate the sediment in the bottom of the float bowls and the car would start. It stayed in suspension while I was driving and for several hours after I parked it.

It took me 10 minutes to remove the tops of the float bowls, then the floats and with a soft absorbent cloth and paper towels, I wiped the sediment out.

The problem never came back. In 1990, during my restoration, I had the gas tank "slushed" with an epoxy coating inside and my gas is always clean. It cost me about $100.00 in 1990 to have this done at a tank and rad shop.

Don Elliott, Original Owner, TS 27489 LO
Don Elliott

It may be that the choke mechanism is not working properly. Sometimes there is too much slack/wear in the cable/linkage. You may wish to check that the jet is actually being pulled down when choke cable pulled out.
Tom Addison

I feel sure I know what the problem is. On my car the rubber grommets between the dashpots and carburettor bodies had perished and gone hard. Petrol slowly dripped out of the dash pots. If the car was left over-night it took a while for the dashpots to refill on the starter. If the car is stopped after it has been used there is sufficient fuel in the dashpots to get it started and once the engine is running fuel is pumped through.
You can test this by looking for fuel leaking out or by pumping fuel through by hand before you try to start the car.
I replaced the rubber grommets and the problem is considerably improved. I can leave the car for more than a week and it will start no problem.
Hope this helps.
n morgan

Nick - That will only work on a TR3A if it is painted red and white.

Why is it that Mike's problem only happens in cold weather ? If it was leaking through crispy bottom SU seals, wouldn't it also leak in warm weather too, giving him these starting problems when it is warm too ?

Don Elliott, 1958 TR3A
Don Elliott

Does it only happen in cold weather, or when the engine is cold?
Maybe he should repaint the car two-tone. By the way, my car is black and white (I can't afford colour yet!).
n morgan

Thanks for the replys folks. I took up some slack that was at the end of the choke cable, and the starting problem seems greatly improved. However, I've since had other troules. Once, gas seemed to be dripping from the bottom of the carbs after tightining the choke cable, which did not seem to have been over tightened. Then it stopped. Last night, on a ride, the fan belt snapped (luckily at my door step)and in doing so,it knocked the fuel feed line off the filter. So I cleaned up the mess, re-connected the line, and left it till morning. Now I notice fuel leaking from the bottom of the carbs again. (all night) Is this because of poor bottom seals as Don mentioned, or is it a float problem? I have no overflow tubes going from the dash pots into the air filters, so I would think a float problem should cause a leak out the tubes, not the carb bottoms.
HELP! The manuals show disassembly and re-assembly, but no trouble shooting ideas. Thank you for any adivce/ideas you could give me.
Mike Gambordella '56 TR3 Comm.#9865
Mike Gambordella

Mike - I think you said earlier that you have the Haynes Manual for SU Carbs. I think that you should buy a kit for the carbs and do a job on them over the winter. If the rubber seals at the bottom are leaking, then other rubber parts will be ready to crumble too. What do you think ? They'll be good after that for over 70,000 miles ! That's what I've driven since.

The only mechanical thing to worry about is how to fit new bushings into each end of each alum. carb housing, (if the holes and shafts look worn after you take them out). If there is slop between the bushing and the rod is worn, air can leak in and change the air to fuel ratio. I had mine re-bushed by a mechanical neighbour (Canadian and British spelling) who drilled out the old ones, pressed in new ones and then reamed them to fit the two new brass shafts that come in the kit.

If the fit looks good - no sloppyness and no wear on the brass shafts, leave them alone.


Also note which way the circular butterfly is installed before you take it out. They only look round, but there is a chamfer on the circumference that must go back the same way later - for a completly closed condition at idle.

As for the fan belt, was it one of those solid types marked "Made in Germany" ? If so, it's no wonder it broke. They are so rigid, they can't flex around the pulley easily enough. I got abot 5,000 miles on my new one (Made in Germany) before it snapped. The type to use is a Gates with a cogged inside. It is much thinner and the cogging effect allows it to flex without breaking. Mine has been there for 65,000 miles and the 2nd one I bought at the same time (just in case) is still in my trunk. They also fit on a lot easier. Being more flexible and thinner, they fit between the front of the handcrank extension and the circular support cross-bar. The big ones are a real pain.

Buy a Gates Green Stripe Belt #695 marked Made in USA.
For readers in Canada this belt is #19A0970

Don Elliott, 1958 TR3A

Don Elliott

Mike - Check out the TR6 site below. They are presently talking, I mean writing about carb re-builds. I have learned a lot from those TR6 guys. I learned that our TR3s and TR3As are really simple compared to what those TR6 guys have to put up with. No wonder they always have about 400 issues on their site.

Our TR3s are about 4 times easier to work on, that's why we don't have as many messages. Or we're just smarter than they are. After all, we bought the simpler TR, didn't we ?

But we're getting up there too ! What about 115 messages ? The challenge is on !

Don Elliott, 1958 TR3A

Don Elliott

Mike-Sounds like it is time to take the SU's apart. The cork seals in the jet tend to harden and produce a leak at the bottom of the jet. When you replace the cork seals, be sure to soak them in oil first so they are more pliable. Both Moss and TRF advertise leakproof alternative seals-maybe they are just o-rings. If the throttle shafts and carb bodies are worn, do not try to rebush them yourself. I have been rebushings carbs with delrin with very good results. If the throttle shafts are replaced, they have to be cut to length and accuratly drilled for the throttle stops. When reassembling the carbs, make sure the cork seal(also soak in oil above the jet adj. nut is fully compressed or it will be impossible to get the mixture lean enough, also make sure the needle is centered in the jet.
Don-TR6 people (me included) are 4 times more neurotic than "tractor drivers"becase there cars have 10 times more problem areas. If you visit the other TR6 list, you notice there are several types. People who are originality fanatics, ones who mostly want to keep their car mostly original(but will make minor mods.for relability&performance),then there are the ones who are trying to make a TR6 into a modern high performance car. For sheer number of messages, nothing comes close to the MGB tech bbs

Don, Berry, Thanks a million guys! Manuals are a necessity, but there's no substitute for experience.
I had a carb rebuild thought in the back of my mind since the PO had casually mentioned rebushing in the future when I was looking at buying the car. But alas, love is blind. I meant to say earlier that there are no overflow tubes going from the float chambers to the air filter mesh, not from the dash pots. Anyway, I'm glad the PO left a cogged belt in the trunk.
Problem is, a TR6 fan was installed on the car for extra cooling duty and it protrudes so far to the front that there isn't enough clearance between the fan and the radiator to pass the belt through! I've even detached both upper radiator stays, disconnected the upper hose and removed the passenger side lower radiator bracket bolt in order to move the radiator forward some. The driver's side lower bolt is pretty near impossible-I removed the nut on the bottom, but the radiator bracket itself is threaded and the steering box is in the way of any socket use. I removed all the bolts holding the circular cross member, but it wouldn't move from it's mounting place. (yet) After about 5 hours doing all that, I STILL don't have enough room! But it's close. Folding that portion of the belt flat, I might have made it, but my time was up. Tomorrow is another day and as I exclaimed with grease covered hands to my girlfriend, "This is the mark of a fine British mechanic!", I moved inside for food and drink. Again, thanks a bunch guys. If I keep it up, I alone might surpass the TR6 thread count! So long for now.
Mike Gambordella '56 TR3
Mike Gambordella

Hi folks. Well, after sleeping on this whole fan belt/carb issue, I may just put the car up on stands for the winter anyway. It snowed/rained/sleeted here all last night and it will all day today as well. So it seems my first ride will be the this year's last. Besides, the radiator itself is a tad wet along the top seam. Might as well dive into "the neighborhood".
Don, I read the carb threads on the TR6 site-Thanks.
I think I'll just pull them off and send them out as complete units. That way, everything can get addressed at once and they can be flow tested, etc. Sometimes when I take things apart I get a little aprehensive about what I'm getting into. Does anybody out there know a reputible carburetor rebuild shop in the central Massachusetts area?
I also read all the Radiator Remval threads as well, so here goes! Any other tips would be great. I just wish I had some experience to offer up in return.
Hey Berry, Your right, there's all kinds of enthusiast levels. Besides, anybody can have a modern high perfomance sports car. Why try and make a TR6 (or any other TR) something it's not? If you go too fast, you miss all the scenery anyway.
That's what I like about the TR3 - 40 mph seems like 70 when your sittin' on the road.
Thanks, guys.
Mike Gambordella '56 TR3 #9865
Mike Gambordella

This thread was discussed between 28/10/2002 and 17/11/2002

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