64/73/79 Dolmar Buildoff Saw Thread MMWS 2019

After some discussion and research, I think I'll be going with a Poleman version of the unlimited 272 coil.

It seems the most easy and effective mod to achieve an unlimited coil on these saws.

Link to the thread by Poleman...https://www.arboristsite.com/community/threads/cheap-dolmar-7900-coil-swap.278777/

 

Some updates. Trying out some pistons for fitment and design..

Not going to reveal my piston choice until later. Gotta keep the racer's edge. Lol.

Size difference of original smaller piston versus the new.



A problem when choosing alternative pistons is the skirt impacting the case and/or crank.




Different view...

 

Proposed piston and amount to be trimmed marked with scribe.

 

Found a machinist today and dropped off my cylinder and piston for some adjustments.

Working on solving my intake problem. The standard elbow flows well, but I'd prefer to improve on it. The HD filter from Dolmar includes a new elbow, but it is known to cause a drop in RPMs and power output.

The two elbows and some sketches I've done.


More pics...

 

Here's a look at the difference of stock 64/73/79 exhaust outlet, versus the modified muffler. The later models are a bit different with the addition of the SLR.

 

Modifying the HD air filter cover. I'm choosing to use Frogzskin snowmobile style mesh pre-filters. This should increase the amount of airflow to the filter.

I abraded the surface and cleaned with acetone before applying the stick on filter. It should have plenty of surface area for the adhesive to grab onto.