• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

TR2/3/3A Ignition Run-On

Share this page

S

smdichter

Member
Country flag
Offline
Carter low pressure electric fuel pump, Pertronix electronic ignition, carbs seem to be properly set, idle at 800. When I turn the ignition off, the engine keeps running a little, bumpity-bumpity-bumpity - brrrr-thud. If I disconnect the battery, same thing. If I turn the ignition back on while this is happening, it fires back up completely.

I think this is called "run-on." How do I stop it?

Also a general question about Forum searches. If I type in run on, it gives me "run, on" and rejects the search request because it will return too many items. Is there a way to string words together? Do you use quotes? Some other method?

Thanks.
 
Put you foot on the brake, leave it in gear and dump the clutch as you turn off the ignition.

Mine will do it sometimes as I really can't get it to idle much below about 900 rpm with the cam and all else that I did to the engine. Therefore, I just got into the habit of dumping the clutch. If timed right, you can't even tell it was done.

Also, I pretty sure the search engine will accept quotes and + signs between the words.
 
If you can get the idle down to the specified 500 rpm, the runon will likely disappear. I can't, though, so I do the same as Art. With a little practice, it becomes habit and you can do it so smoothly you won't know if the engine wanted to runon or not. But be sure to keep your other foot on the brake, just in case it tries to go another turn.
 
What do the plugs look like? If they have carbon or oil deposits the motor will diesel on also. Sometimes when the distributor does not operate correctly deposits will build up also causing the same problem. When I shut my tr3 off, it stops right away.
 
I had the same problem for a while. Try running a tank or two of high octane fuel. This should run hot enough to burn out the carbon deposits that are causing your run on. If the problem comes back on regular, make the switch to premium. Worked for me.
 
My 1960 TR3a has been running on since I bought it 6 months ago I have tried cooler plugs, lower idle,moving distributor?? both ways,high test gas, even driving at
4000 rpm for 30 minutes (to remove carbon) no change.The car runs extremely well plenty of power next move remove head and check for hot spots ? meanwhile
stalling out works for me
Dave.
 
Back
Top