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TR2/3/3A TR3 Fuel Problem

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martx-5

martx-5

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Well, I have developed a problem with the TR3 engine. My procedure to start the car has been to pull open the fuel shut off valve, prime the carbs with the lever on the fuel pump, pull out the choke, turn on the ignition and push the starter button. A second or so later, the engine is running. However, I've developed a problem after running about 30 seconds or so. The engine drops the two back cylinders. I opened the float chambers and noticed the the back float was down...no gas. The front was OK. Stop the engine, re-prime the carb floats with the lever, and the same thing happens. Thirty seconds later, it starts missing, and the back float is dry. I did notice, that while priming with the lever, it took a lot more movement to feel the pressure of the gas going into the floats...way more then usual.

The fuel pump was rebuilt awhile back with a kit from TRF (there is only about an hour and a half on this engine). I've read about bad diaphragms for these pumps. Is there a possibility that I have a bad fuel pump diaphragm??? What do I look for when I take it apart??? and Who has good rebuild kits??? If, this is the problem.
 
Art_ I've had my fuel pump apart many times.
You would readily notice a rip or tear on the diaphram.

I'm not totally sure but I think a torn diaphram would
permit gasoline and engine oil to mix. Maybe your rear carb float valve is stuck?

But heck! I ain't no wrench.

d
 
Art,
I've had leaky diaphrams before and they still sent enough fuel thru to run properly, I usually found them by the oils contaminated smell/look. I'd look for a line blockage (crud) or an issue with the needle/seat assembly.
Try switching the float chamber covers and see what happens.
I'm still using a stock pump but check it regularly (and the oil) for any issues as a leaking unit can really bung up the oil and introduce a nice solvent everywhere in the motor.
 
Good idea on changing the float chamber covers. That's a whole lot easier that taking off the fuel pump.
 
martx-5 said:
Good idea on changing the float chamber covers. That's a whole lot easier that taking off the fuel pump.
Click to expand...

Well, I changed over the float chamber covers, and didn't expect what I got. I thought that if there was a problem with the float valve it would follow to the front carb. That didn't happen. The darn thing runs great! Had it going for about twenty minutes. Someone try to explain this to me. :wall:
 
Stuck needle. Are you using the roller model or the needle? My experience has been the rollers/ball type is way less prone to sticking, but it is suggested that they use more fuel. One thing I would like to suggest is to try and keep your fuel mixture a little lean, especially in the beginning. I have washed out the ring seating by running the mixture to rich before. So get the choke back as soon as you can, and I suppose the needle type bowls would be best at first.
 
Check the reed valves in the fuel pump. The garbage fuel [mehanhol Mixed]wrecked havoc on TR2.The reed valves swelled up and wouldnt pump when the engine got hot.I had to take all my old spare fuel pumps apart soak 16 reed valves in fuel and come up with 8 good unaffected ones.My TR4 has never had any problems[The pump it 30yrs old].The rebuild kit that I used was also from TRF that gave me trouble. I dont blame TRF.The US govt idiots are The Problem with their federal mandates. I now live in Northern NH. and you can buy methanol free hi test at the Lakes region gas stations.They supply it for the boaters who had all kinds of problems with bad gas. My cars run fantastic on the GOOD Stuff and no problems.
 
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