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TR4/4A Fuel Flow problem? question

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thechileman

thechileman

Jedi Hopeful
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Took my TR4 out for a Sunday drive last week. She ran fine for a while, and then it seemed like I was losing 2 cylinders. Pulled over, let her sit, fiddled with stuff, burnt my hand on the oil filter, (lol...) Started her up and she ran fine for a while, and then the same symptoms occurred. Let her sit again, and she ran fine getting her home. The car had no fuel filter, so I thought I may have gotten a piece of dirt in one of the float bowls, and it finally flushed through. So this morning I decided to install a fuel filter. One of those clear ones with the removable filter element you get at Pep Boys. It installed fine, car seems to runs good.

So here is my question. The fuel filter never fills up with fuel. Having never used a clear one before, this surprised me. Is this normal? The car ran fine with the filter, carbs getting fuel, even under full throttle. I am running a mechanical fuel pump, purchased new from Moss about 2 years ago.
 
Is the filter before or after the pump? It should be full of fuel.
 
Unless you've mounted the filter vertically, with the outlet on top, then there will be an air bubble trapped inside the filter. It doesn't mean anything.

In other words, the fuel level inside the filter will rise only until the outlet is covered (so no more air goes into the outlet) and then no farther. Slowly, over time and driving, the level may rise more as the fuel sloshes around (and pushes up against the filter element during higher flow) and lets some air out. But that can take years and still not get all the air out. The air can only go into the outlet, there is nowhere else for it to go.
 
Filter is after the pump MTL. Randall, that is what I thought I was seeing. Thanks. The outlet of the filter is lower than the inlet, so the air will probably always be there.
 
Most aftermarket fuel filters do not fill up. Can't explain why but have seen this condition on American V8s, farm tractors and other gas engines as well as our LBC's. TR4's, 250 & 6 gas lines gum up when they sit alot. The car will run fine for a few minutes then die after it sucks all the gas out of the pump and line. Let it sit for a minute and it will run fine again only to die a little later. Change out the entire gas line, its not that bad of a job.

Marv
 
Marvin Gruber said:
Change out the entire gas line, its not that bad of a job.
Click to expand...
Or what worked for me, when the line plugged up on my TR3, was to blow compressed air backwards through it. Probably should have stuffed a rag into the fuel neck, as it splashed fuel out onto the rear deck; but at least it solved the problem. But in my case, I think it was dust and dirt (and paint) that fell into the tank while it was sitting in the body shop with no gas cap (rather than gum from old fuel).
 
That will clear it and I have done that several times but I'm finding that the line walls have build up and are closing in from the gas varnish.

Marv
 
I had a similar problem a few years ago with my 1958 TR3A. I was on a 400 mile trip and after 100 miles from home, it started to baulk and lose power. I stopped about 5 times to try everything. But after a few minutes, it would always re-start and run for another 5 to 10 miles till it happened the next time. One time I only coasted in neutral onto the wide shoulder to let the whole crowd behind me get by. I never stopped and after the crowd was by, I pulled out onto the road with full power for the next 10 miles. Then it happened again. So I would put it in neutral anytime I was rolling at speed downhill. I got to the next town and filled up with gas and added my usual upper cylinder lubricant (4oz of Marvel Mystery Oil or Lucas "Gas Saver"). They only had 89 Octane gas. I ran the rest of the trip in record time with no more problems. The day after I was cruising at 90 MPH on the multi-lane highway to British Car Day in Bronte Creek, Ontario.

I blame all the trouble on a tankful of "BAD GAS". I have never had this happen again in over 7000 miles.
 
Don Elliott said:
I blame all the trouble on a tankful of "BAD GAS". I have never had this happen again in over 7000 miles.
Click to expand...
Just curious, Don, have you added a paper element fuel filter? Your experience sounds very similar to some I've had with other cars, where the "bad" part of the gas was that it had some water mixed with it. The water causes the paper element to swell and close up, until it won't pass enough fuel to keep running at speed for very long. Often there is some slower speed where it will keep running. I once limped some 20 miles at about 10 mph before I found a parts store with a replacement filter.

But in many cases, I've just jammed a screwdriver through the center of the paper element filter and gone on. This was before they started adding ethanol or MTBE to fuel, though. The ethanol in effect ensures that you have either no water, or a whole lot of water/ethanol mix. I'm guessing you can still get the "good stuff" where you are.
 
Randall - I can't say for sure but the gas station where I bought that suspect "bad gas" was a new station. It was "Petro-Can" where I have had trouble with their gas before. This time, I had no upper cylinder lubricant with me so I filled up with the highest octane (98) which here means it has no ethanol. I remember it cost me $1.55 CDN a litre ($5.90 per US gallons in US Dollars). Since it was a new station and when you consider the price, I did not expect the gas to be "bad". But I have no other explanation.

I have a paper filter but it has never caused me any problem - except for that one time -and I can't say it was the filter. As for good stuff, I'm running with ESSO, or Shell 89 octane plus the upper cylinder lubricant. They have less ethanol, or my selection has eliminated all my fuel problems.

Last Saturday I drove to Ottawa British car Day (130 miles in 2 hours and 20 minutes) each way running with 10W30 Castrol and even a 12 year-old Chinese girl was able to use my hand crank to start the engine. It was idling at 400 RPM and needed no zap on the throttle. It runs as smooth as silk.
 
All the symptoms you described including the minimal fuel in the clear filter I had in my TR250. Made all the fuel filters changes too along with a fuel pump. Would work for 2 of 3 miles then die. Shined a flash light into the tank and noticed that the lining was coming off and plugging the hole. Replaced the tank and blow out the fuel line backwards with 150 lbs of air and brake cleaner. This must have been happening over time because the performance of the car came back and my fuel filter is almost full.
 
Thanks Got. I took it for a drive this weekend, and it seemed to work OK. Just as a precaution, once I burn off most of this tank of gas, I am going to take a look in the tank. Its one thing I didn't mess with while restoring the car. I may need to pull it out, and give it a good clean.
 
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