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TR2/3/3A Hard starting when hot

TR3sharon

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I've been sorting out a fuel issue with my TR. After swapping in a new tank, I'm frequently change fuel filters because I foolishly didn't change the lines while I had it torn down. Now that I think most of the gunk has run out, the car is refusing to refire when it's hot unless I push start. Starts great when cold. Related to the fuel or new issue like say, timing?
 
You say it will start when you push it? Sounds like an ignition problem, related to the battery voltage drooping while cranking.

Or what a lot of people (myself included) have experienced is the fuel boiling in the float bowls and jets, pushing fuel out into the intake manifold and causing a very rich condition. This typically shows up after driving fairly hard (like uphill or freeway speeds) followed by immediately shutting the engine off for 5 to 20 minutes or so. On a club run a few miles back, after we stopped for a "biology break" in the mountains, there were quite a few of us that almost couldn't get them started again. I can't explain why, but it seems to have gotten much worse with ethanol in the fuel.

In my case, adding a heat shield under the carbs made a big improvement, although it still runs a little rough at first under those conditions.

Another thing that seems to help is to follow the book suggestion and hold the throttle partway down while cranking when hot. I think it helps move more air through the carbs & manifold, to clear out the excess fuel.

Here's a shot of the heat shield as I was installing it.
 
Have you considered a coil? If you have a spare swap it out just for a try.
Bob
 
Updated: Battery was the winner! Thanks for the help



The coil is only a few years old, limited mileage. Now the battery, a whole other story. I imagine fresh plugs wouldn't hurt either.

That is one slick looking heat shield.
 
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The coil is only a few years old, limited mileage.

Moot point now, but I had a new Lucas coil fail within about 10 months of installation. You just can't trust "new" parts to always be good!

Just got done changing the water pump on my TR3. Apparently, the "high tech" pump I put on last year must've been leaking just a little bit from the very start. Since it had no weep hole, the bearings filled with water and eventually seized; whereupon the shaft started turning inside the bearing races! Just incredible that I never noticed any bad noises, or belt slipping, etc. The shaft is now a good 1/8" undersize, from wearing against the inner bearing races, and of course incredibly sloppy once the fan belt was removed.
 
Moot point now, but I had a new Lucas coil fail within about 10 months of installation. You just can't trust "new" parts to always be good!

Just got done changing the water pump on my TR3. Apparently, the "high tech" pump I put on last year must've been leaking just a little bit from the very start. Since it had no weep hole, the bearings filled with water and eventually seized; whereupon the shaft started turning inside the bearing races! Just incredible that I never noticed any bad noises, or belt slipping, etc. The shaft is now a good 1/8" undersize, from wearing against the inner bearing races, and of course incredibly sloppy once the fan belt was removed.

It wasn't one of those 6 blade pumps from Moss? Mine's making a racket since I swapped to it.
 
It wasn't one of those 6 blade pumps from Moss? Mine's making a racket since I swapped to it.
May be the same pump, but I got mine from BFE a long time ago; before Moss started offering them.
 
It wasn't one of those 6 blade pumps from Moss? Mine's making a racket since I swapped to it.
Check the pump for signs of rubbing from the pulley. Mine needed a little grinding on the housing to quiet down.
 
Check the pump for signs of rubbing from the pulley. Mine needed a little grinding on the housing to quiet down.

I clearanced it prior to fitting. I'll double check just for peace of mind however
 
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