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TR5/TR250 Stumped TR250 Running Rough--Follow Up


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So I posted a while back about my TR250 not wanting to rev and having a miss. Last post I noted if I pulled the plug wires on cylinders 1-3 it didn't seem to make a difference, but 4-6 it stumbled and missed as expected. So I was thinking front carb issue, but haven't had a chance to get back to do more work til now because of my schedule and some very cold weather.

So I went back today with some hand tools and a compression tester and a timing light. Compression was 145-155 psi across all six. I then took the front fuel needle and jet assembly off the carb partially disassembled it and sprayed some carb cleaner on it. Noticed a bit of crud.
Slapped it back in, started her up, immediately seemed good because I was getting a high strong idle on the choke. Let her warm up and took her for a test drive. Pulls strong again to redline.

Operating under the old premise that 90% of carb problems were electrical in nature I spent a lot of time chasing down the wrong Gremlins. But very happy to have her running right again.


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Thanks to all for the replies on the prior thread, you put me on the right track. Very sweet music to my ears too
Last edited:

Marvin Gruber

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This new gas goesn't play well with these old side draft carbs, my E type is the worst. If I don't run the car for a few weeks I have to clean needles or drain the tank and put in new gas. TRs not as bad but they split and sputter until engine gets hot and cleans itself.

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