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3 now won't start

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The grommets (like top hats) on my SU carbs are black rubber and have been there since I did my restoration from 1987 to 1990. They are fine. I had them out last week to look at them. They are located where the extension arm under the float bowl is secured with the large special nut to the bottom of the carb body housing.

I can't believe that your grommets have suddenly become rotten when you are still flooding the cylinders with too much gas as you reported earlier about the plugs being so wet so quickly.
 
Once again, thanks fr all the good advice. The float bowls are definitely getting cleaned and adjustd. I have tried to find plugs locally, but so far without success...eithe Chanpion or NGK.

PeterK, I do have the chart that shows the relationship between the lift pin and affec on idle. I will take your suggestions on technique to heart. I think that the you are correct the timing is a bit retarded, and it will try advancing first per your suggestion.

If you could email the cheat sheet you mention I would greatly appreciate it.
 
Re: 3 now WILLstart

Update: today I cleaned both float bowls, took put the needles and clened, thenput everything back together. I then started the car /bcforum/images/%%GRAEMLIN_URL%%/grin.gif and let it warm up. Then I checked the timing marks with a light. My light has a a dial on the back that, if I'm understanding correctly, you can turn to til the marks line up with the pointer to determine total advance. If the above statement is true, it's reading 25 degrees. I revved the engine to see how much movement I was getting per PeterK's suggestion. Zip, Zilch, None. The sadpartis I remember doing this before the whole "won't start" problem and it did move when given more gas. So, it woudl appear that the vacuum advance has decided not to function. God I love this car. So how do I address that problem.

Also, I had done the lift test on both carbs after cleaning the float bowls. One seemed fine, that is witht the lift pin up the engine slightly increased and leveled. The other carb immediatily decreased. I backed off the jet a flat, and then another and then it tested like the first. I then went for a short drive /bcforum/images/%%GRAEMLIN_URL%%/driving.gif. Did well. Missed a couple of times but nothing like before. Of course, it stillidles high, which goes all the way back to the original problem I was trying to address. At this point if I can get everything else ironed out, I'll just live with the high idle.

So, how do I tackle the vacuume advance?
 
Re: 3 now WILLstart

How to check if the vacuum advance is working ? Make sure your TR is not running. You remove the connection at the front end of the distributor where the tube goes to the bottom side of the aluminium body casting for carb #1. Then put your lips on the end of the fitting on the front of the distributor and "SUCK". If you see the points rotate on the base in the distributor, it's working !

Let us all know what you find out.
 
Re: 3 now WILLstart

I had a vacuum advance that filled with gas after a flooding problem like yours. I think the diaphram is actually metal.

The diaphram assembly goes all the way through the distributor on comes out on the right side of the advance know. On the right side of the advance knob there is a small wire "U" that fits in a recess groove on the outside end of the advance (on the right.) You'll need to remove the U - note there is also a small flat piece of spring steel that keeps the advance knob from turning. Many distributors are missing this piece because it's easy to lose them. So have a magnet near to catch it.

If you are up to it, I recommend pulling the distributor to remove the vacuum advance. Make sure that you scribe a mark on the distributor base and the clamping bracket for when you put it back in. Also note the position of the rotor when you pull it.

Once you remove the "U" ( which is really just a bent piece of steel wire), the vacuum will be loose, but it also has a connection to the points plate with a loop end of a spring attached to the vacuum unit that goes over a brass pin on the points plate. You'll see it when you get to this point.

Two screws hold the points plate in the distributor case. Remove the points and these two screws - hey, you're this far so let's go. Now pull up on the points plate and remove it, detaching the sping loop from the vacuum advance unit. The plate is actually two plates that pivot when the vacuum pulls on the spring that goes over the pin on the plate. OK take pictures before you take it all apart but trust me, it's pretty basic, you can easily do it.

Now look at the points plate. The two halfs should be lightly greated so they pivot. Old grease binds them up. So hit them with some brake cleaner and put some electric grease on them for reassembly. Good time to add a couple of DROPS of 30W oil to the distributor shaft now too.

OK back to the vacuum. Shake out the gas - it's full isn't it. Then hit it with some brake cleaner because brake cleaner will help evaporate the remaining gas. Let it dry out in the sun for a few hours. Shake it some more. If you want to test it and you don't have a vacuum tester or vacuum brake bleeder, suck on the end and you should be able to feel a little movement but not much.

Now put it all back together but this time set the advance wheel at the mid-most hatch mark, and align your distributor base with the mark on the clamp that you made.

Your jet works sounds perfect! Keep backing or turning in a flat ot two or three and testing. I find if it misses when warm, it's a little too lean so out 1-2 flats and retest. It must be warmed up to do this. It can also miss if not warmed up. Make sure you know where your choke position is (just in case you weren't paying attention!)
 
Re: 3 now WILLstart

Well good deal Ed, it runs. Yes it sounds like the whole problem could be the vacuum advance because if it is shot the timing will keep pull up and so will the idle. I am not sure if you can buy the vacuum advance separate from one of the big three or not, but I have seen them NOS on eBay. They are not hard to put on, the distributor is very basic. In fact, not long ago, I went to my neighborhood auto parts store and bought a rebuilt distributor for a tr4. I think Sunbeam, MGA, some Austin’s all used the same distributor. I paid like 70 or 80 bucks and was shocked that they could get one. Give it a try you never know.
Sp53
 
Re: 3 now WILLstart

Ed, did you tighten that loose connection to the vacuum advance at the distributor?
 
Re: 3 now WILLstart

Ok, just spent my lunch hour sucking on my distributor. Not a pretty sight. Actually I used a piece of tubing, so wasn't quite as bad as it sounds.
Anyway, the points plate moved without any problem. I do think I got a bit of gas. Glad I was using the tubing. I then diconnected the feed from the carb and blew some compressed air through. More moisture. I squirted a tad of carb cleaner in the vac advance unit. Sucked again and let things dry, then reinstalled the feed tube.
Started the car (I really like saying that) and it purred like a kitten.
Ran out of time so I didn't check with the timing light on it to see if the advance was moving the marks. I'll confirm that as soon as I can.

This all make sense?
 
Re: 3 now WILLstart

So does anybody see any reason not to put the Pertronix ignition back in? Obviously taking it out did not resolve the problem. Seems a shame in a way to take out the points after spending so much time getting them set and timed, however....

No one asked what I thought finally remedied the problem. In case you are curious, thinking back through events, I don't think the rough running and eventual failure to start had anything to do with either carboration or ignition/timing. When I think about the things I did between not running and running (that is, just before it start running) the thing that stands out most is the addition of a bottle of gas drier to the tank. I really think that was it all along. On the postitive side, I sure learned a lot about the car. All's well that ends well.

Now whaddaya think? Put the Pertronix back in? And of course I need to change the oil again due to the gas contamination.
 
Re: 3 now WILLstart

Ed, I am a proponent of the "If it ain't broke, don't fix it" School of Thought.

Will you drive him to Harry's Grill tomorrow?
 
Re: 3 now WILLstart

Hey John...not sure if I'll be making it to Harry's tomorrow or not. Weather doesn't look so good, and it's a 3 hour round trip for me.
 
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