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TR2/3/3A Where did all my TR3 bottom end power go?

jsneddon

Jedi Knight
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I have been staring at this problem too hard and now I can't see the forest for the trees. Hopefully some of you can point out something that will make me slap my head and say DOH!

I have a TR3 that sat for 10 years. Prior to parking it I had rebuilt the head. After the rebuild I had about 130psi per cyl. and it ran like a scared rabbit for 6 months until I put it in storage.

I got it running again about 2 months ago. But it has no bottom end power. Above 3000 it feels pretty "right" but getting to 3000 feels gutless when I put my foot in it - not even under load. Under load I could barely get it up the hill around the block at full throttle in first gear. On flat spots it will get up to speed but it doesn't feel right.

Depending on where I set the advance I get a good deal of sputtering and coughing back out of the carbs until it gets up to 3000. I can "ease it" up to 3K but if I put my foot in it it sputters and coughs.

Here's the facts:

* Rebuilt Carbs
* Dashpots rise equally, don't seem to be binding, airflow is balanced.
* Mixture seems to be OK from the "lift the pin" method. If I crank the jets up or down I get the appropriate "speed increases" / "speed decreases" response. Currently the jets are set so that I get no change when lifting the pin
* Floats are filling up appropriately
* no vacuum leaks found with a liberal hosing of carb cleaner while running
* New Points, Condenser, Coil (I just threw all my spares at it in a fit)
* Static timing has been adjusted 6 ways to sunday - 4 degrees, 8 degrees, timing mark at the mark and dialed in, timing mark 3/8 inch and no dial in, etc etc etc.
* distributor wieghts and springs are free and clean and move
* vacuum advance pipe is clear and connections are good
* new spark plugs - plugs that had sat in the car were black
* everything from the tank to the carbs has been flushed - after 10 years it was completely clogged.
* brakes have been completely rebuilt and nothing is dragging.
* oil changed

Here's what I'm going to try next:

* I'm going to floor it and shut off the car - see if i'm missing fuel in the floats- I could see where I'm still getting gunk in the lines but that doesn't make too much sense to me since it runs better at high revs - I'd think fuel starvation would be worse at higher revs.

* Dashpot oil is currently ATF (it was what I had on hand at the moment I needed some) - I'm going to replace it with some 30w I guess.

* pull spark wires one by one and see if I get the same change on each.

* I haven't checked the valve clearances lately - I reset them about 4 years ago when I was trying to get it to run but life got in my way again.

* Get a timing light with an advance and try the suggestions on the previous TR3 Ignition Timing Help thread.

* replace my missing compression tester and see where I'm at today.

Any other suggestions/tests/ideas would be appreciated.

Thanks!
 
I certainy concur with pulling plug wires one by one, checking valve clearances & a compression check.

What you describe sounds like you might be running on 2 cylinders -- this could happen if you have a stuck needle (or grose jet) in the fuel bowl but it sounds like you checked that already.

At the risk of suggesting the insultingly obvious... have you confirmed the firing order is 1-3-4-2? The 3 & 4 wires can get switched if they are long enough.
 
Geo... I'm never insulted by someone pointing out the obvious. This was exactly the second brain looking at the problem that I needed.

My firing order was set to 1-2-4-3... I had the two middle wires switched !!!!!!!!

Attaboy Geo!

swapped them and now it runs like a scared rabbit again!

I owe you a beverage of your choice /ubbthreads/images/graemlins/smile.gif

THANKS !!!!!!!!!!!
 
How does Geo do it? I think I owe him a 6 pack by now with all he has diagnosed on my TR4. Makes me believe he could lay his hands on a TR and it would fire right up!! /ubbthreads/images/graemlins/cheers.gif
 
Maybe we can get Basil to sponsor a "BCF Member of the Year." I definitely think Geo is top contender!
 
[ QUOTE ]
My firing order was set to 1-2-4-3... I had the two middle wires switched...

[/ QUOTE ]

The ignition wires on a TR3/4 can be trimmed such that they can only be connected to the correct cylinders (e.g. you could still connect 3 to 2 but 2 would not reach 1, 3 or 4 and you would know it was wrong).
 
Hey, maybe we could make Geo "the Fonz" of the LBC set-- 'Cept he can lay hands on thru cyberspace.
 
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