288xp lite.. to squish or not to squish??

[sweidish445]

I decided to field test the Permatex on this 288. This saw has cost me so little, I've come to appreciate it even more. I didn't expect huge compression numbers so 160psi before break-in = not to shabby.

Runs excellent after some tuning. Only hick-up there is I can't seem to tune idle low enough. T screw fully out, tuned kinda rich I'm running 3000-3100rpm Hot. Chain tends to spin at startup. The air vent on top cover is closed!

Its not the end of the world, the saw runs awesome. It'd be nice for it to be safer incase a buddy uses it. I'd also like the low idle pop .. Any suggestions??

 

[HuskStihl]

When mine did that it was leaking from the stupid phenolic block intake

 

[HuskStihl]

Some dummy forgot to shave the area the block sets in. [emoji12]

Another dummy, who looks remarkably similar to the other dummy, figured out how to trim that stupid black plastic "carb compartment separator" thingie, and file the bottom of the blocks a bit. To the OP, that will only apply if the base is machined.

 

[sweidish445]

Mityvac 8500 is in the mail. I'll pressure test for leaks asap. I did not machine the jug, but didn't consider removing the gasket could throw it that far out of whack.. I will follow up when I figure it out. Thanks!

 

[HuskStihl]

Just removing the base gasket won't cause an issue, but I would replace the gaskets in the intake system, and make super sure to clean out all the old gasket stuff, and make sure you don't block the impulse pathway. I can't remember the whole thread, but have the crank seals been replaced?

 

[DrewUth]

Richen the L side a bit, that will bring the idle down.

 

[sweidish445]

Just removing the base gasket won't cause an issue, but I would replace the gaskets in the intake system, and make super sure to clean out all the old gasket stuff, and make sure you don't block the impulse pathway. I can't remember the whole thread, but have the crank seals been replaced?

 

[sweidish445]

This dummy has been dragging his feet on this project.. 288 is still on the bench. Trigger job for my browning sporting clays 12 gauge took priority. Ive also been making rubber gaskets and plates, de-comp valve adapter, and junk for pressure testing.

I installed all new gaskets and everything was spotless for reassembley. I didnt go down to the bearings, they seemed ok..

Drew- i forget exactly, but i peeled out the limiter caps on the tilston 283 and had L needle pretty rich. Somewhere around 2 turns out if im not mistaken.

I have yet to successfully vac test the saw, but when i get to it, ill pull flywheel, and clutch and finally pressure test, shave separator, and see where im at..

Im going to wave my rookie flag with this question, but is there an external impulse that needs to be plugged?

 

[HuskStihl]

The impulse comes out thru the intake area and lines up with the block area

 

[sweidish445]

The impulse comes out thru the intake area and lines up with the block area

Found my leak! The outter seal behind the oil pump seems to be the culprit. Ordering new, but im wondering.. Is it stupid of me to not replace the bearings and ALL crank seals at this point? If i had a case splitter i would be much more willing to start from square one. Again, the bearings seem fine, and i will pressure test again to check all seals before reassembly.
I'm also considering pulling the jug for assesment. Id say the saw ran for 20 minutes total with the leak and made about 4 cuts. Its hard to tell with my flashlight if it caused any damage to my top end.
I guess another rookie question would be, if i have the jug off, should i mess with these jug skirts?

 

[tpope]

There's several o-rings that you should replace on the oil pump when you replace the crank seal.

 

[redfin]

Found my leak! The outter seal behind the oil pump seems to be the culprit. Ordering new, but im wondering.. Is it stupid of me to not replace the bearings and ALL crank seals at this point? If i had a case splitter i would be much more willing to start from square one. Again, the bearings seem fine, and i will pressure test again to check all seals before reassembly.
I'm also considering pulling the jug for assesment. Id say the saw ran for 20 minutes total with the leak and made about 4 cuts. Its hard to tell with my flashlight if it caused any damage to my top end.
I guess another rookie question would be, if i have the jug off, should i mess with these jug skirts?
View attachment 473363

Just clean up the bottom edge if there is a lip there.

 

[sweidish445]

There's several o-rings that you should replace on the oil pump when you replace the crank seal.

I think thanks all of them..

 

[sweidish445]

Too many forums come to a hault without the happy ending..
Its been a while, but my 288xp lite is back from the dead. Finally reassembled a few weeks ago. Last weekend i got out to do some clean up after a small twister came through the area. The 288 is quite a beast! Maybe not ideal for hauling around doing clean up, but it makes quick work of anything in its path!

To review, i did slight port work on transfers, intake, and exhaust. Omit base gasket, for a squish of .024in. Shaved compartment seperateor to compensate for squish. Opened stock muffler port. Replaced oil pump seals and o-rings. Removed decomp valve and replaced with proper plug.
*Verified no air leaks!
Tested 160 psi after rebuild. Not all bad considering the condition i found it in and the little money i have into it! Ill likely use this for my milling saw as i beileve its better suited than my 372.

Long story short, im a pretty happy camper with this one... thanks for everyones help too!

 

[Full Chisel]

Looks good!