Getting the best performance out of 3400 Counter-vibe poulans....

[Dieselshawn]

Hello fellas, does anyone here have tried getting more pep out of 3400 counter-vibe poulan saws?

My buddy got a freebie one that was supposedly seized but it was just a loose nut that the saw choked on and was found in the crank case.

After just a $2 hose replacement, a little muffler mod, it runs good and getting better.

With a sharp chain, spraying chips, it cuts decent but have to let the saw cut, keep the rpms up, no lifting on the handle.

 

[cobey]

I have a 3700 that's ported, I would start with compression and advance.
That should be a good started point

 

[Dieselshawn]

Best way for compression increase?

I made a base gasket for it to replace the old one.

Remove it, sealer? Or needs a gasket of certain thickness?

 

[paragonbuilder]

Best way for compression increase?

I made a base gasket for it to replace the old one.

Remove it, sealer? Or needs a gasket of certain thickness?

If you have some .023 solder it works good to check. What you want is to have the piston as close to the cylinder top a TDC as possible. But you need to allow for heat expansion while running. Pull the plug and stick the solder in the hole to the edge of cylinder above the wrist pin. Pull the saw over. See if it crushed the solder at all. If not I fold the solder back in itself and twist it and do it again. It should now have been crushed. Measure the crushed point. Also measure a piece of the gasket material you used. You want to get it down to about .020".


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[paragonbuilder]

If you can remove the gasket completely and still have around .020" or better than just use hondabond or equivalent.


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[Mycamaro_68]

I have several saws of this series and planned on starting with gasket delete, muffler mod and timing advance. Definitely subscribing to see what others have to say!

 

[Hoggwood]

Even with a base gasket delete you will be way North of 0.020" squish. I have done away with the gasket on a few low hours 3400's. They are usually around 120-130 psi tops. Lower compression by nature. I have some mufflers modded with single and dual side ports and diffusers opened up. No real difference that I can tell over the stock mufflers. I haven't advanced the flywheel nor taken the cylinders down. The 3700 and 4000 have noticeably more torque.

Just solid, reliable, ergonomic saws. IMHO, the best mod is a 16" bar, a super sharp chain and a light hand.

 

[cobey]

Even with a base gasket delete you will be way North of 0.020" squish. I have done away with the gasket on a few low hours 3400's. They are usually around 120-130 psi tops. Lower compression by nature. I have some mufflers modded with single and dual side ports and diffusers opened up. No real difference that I can tell over the stock mufflers. I haven't advanced the flywheel nor taken the cylinders down. The 3700 and 4000 have noticeably more torque.

Just solid, reliable, ergonomic saws. IMHO, the best mod is a 16" bar, a super sharp chain and a light hand.

The 3700 I had ported if faster in race cants, haven't used it anywhere else.
A buddy had one with timing advanced
It seems to pull harder

 

[smokey7]

Got a few if these to build too.

 

[Magic_Man]

I've got a craftsman 3.7 which is a 3800. I haven't done much with it other than throw new rings in it and hand cut the base down to get .025 squish.

 

[jasper89]

I did just about the same things as the others:
Delete base gasket
Advance spark
Cleaned up the exhaust port
Smoothed out the intake
Exhaust mod (Gills cut in the sides of the muffler)
New rings

It is a reliable old saw with not much $ investment and I can take some satisfaction that I did it myself. A fun project.

Frank