TR2/3/3A Mini Pulses at Idle

Hey Friends, hope you all have had a good summer of cruising and wrenching! I have had a small irritating issue for the last few weeks and I cannot seem to get to the bottom of it.

My engine pulses at idle. Like mini surges. Imagine at the same stroke of the engine. I’m leaning towards the fuel pump, but not sure why that would cause it if the floats are full. Could be that the carbs aren’t synced, but I’ve done everything you’re supposed to do to sync them (I have the vacuum tool and I’m turning my fuel mixtures the same...)

Anyone else had this issue? Or better yet found some relief from it? I’m ready to dive a little deeper in to this to get my idle back...

Mine does the same thing. Have had my TR3 for three months now so I am new to what they should sound and run like but I have wondered if this pulse as you have described is normal or something that can be illuminated with a tuneing procedure. I am currently experiencing a rattling in the engine which I think is coming from the timing chain. It is getting louder as I put more miles on it so I was thinking if it is a loose timing chain could that cause a pulse in the idle??

What RPM are you idling at?

Mine lopes or surges if I drop the RPM down below 800.

David

I don't think TR3 motors like to idle under 800 rpm. Mine seems happy at around 1200 rpmeaceful:

I have mine set to idle at 850. Seems to do fine. Any slower and it starts to do the loping bit.

David

Can you better define "pulses"?

Try putting some heavy oil or grease on your throttle shafts where they go through the carb bodies and see if that stops it. If so that would mean the shafts and bushings are worn. The oil wont fix it but it can seal them temporarily and let you know if that's the problem. Sometimes you can feel the play too if they are loose. Just a thought.
Tom