Poulan PR4218 need to vac/pressure test the block

[Okie]

I've vac pressure tested other chainsaws but not a Poulan Strato like this one.
Appears maybe i need to completely remove the block from the case mainly to block off the 4 screw intake manifold port area.
I put 3 different donor carbs on this saw and each one has exact same symptoms, a high idle, the idle screw is completely off the adjuster, throttle butterfly is closed and only way to slow down the low idle is too set the idle adjust jet about 1/2 turn from it's normal setting and then the H will bog. Saw starts good and only runs good at the high idle area and cannot slow down enough to stop the chain clutch. (clutch is good)
Appears to be a air leak and maybe at the carb rubber manifold boot area or ????

Block will have to be removed from the case to get to the FOUR intake rubber intake manifold assembly screws.
I suspect the clutch side seal area because the plastic is melted in this are due to the saw being operated with the chain brake en-gauged.

Anyone have any pointers or comments about pressure testing one of these type Poulan strato blocks.

 

[Lightning Performance]

Put seals in it

 

[Okie]

Put seals in it

After I posted I went looking at seals and those crankshaft seals look kinda wimpy made in the pictures. The clutch side crank seal area got hot enough to melt plastic and ruined the clutch spring so the crank seal on that side is of failure interest. The saw came to me non-running and melted on that side. The plastic Oil pump got hot also but still works but does not look very healthy.
If I cannot vac/pressure so as to actually see a leak I'll just use it as a donor parts saws for carb, bar chain, etc.
It has very good compression and has the ES effortless start) recoil assembly. Appears to be low hours but a Poulan with low hours may be at the upper end of it life.

 

[Lightning Performance]

After I posted I went looking at seals and those crankshaft seals look kinda wimpy made in the pictures. The clutch side crank seal area got hot enough to melt plastic and ruined the clutch spring so the crank seal on that side is of failure interest. The saw came to me non-running and melted on that side.
If I cannot vac/pressure so as to actually see a leak I'll just use it as a donor parts saws for carb, bar chain, etc.
It has very good compression and has the ES effortless start) recoil assembly. Appears to be low hours but a Poulan with low hours may be at the upper end of it life.

Pressurized air and some flat rubber to use as caps, if you will, is all you need to seal it up. Air pressure and soap or a dunk in a water tank will show the bubbles.

 

[Okie]

The PR4218 is in the woodpile starting easy cold and hot, oiling and idling and cutting good with a 3/8 LP 18 inch roller tip donor bar.
The clutch side seal was leaking. Probably due to the saw being operated with the blade brake on and severely overheating that area.

I had to completely remove the clamshell block from the case, made the block off plates and rubber gaskets seals for the pressure test,
Then drift punch out the steel clam spacers from the plastic case so as to use the block clam clamp bolts, blocked the muffler port, carb intake port, and just held thumb over the strato port hole and injected 5 psi into the spark plug hole using a compression tester as an injector with the schrader valve removed. I had other salvaged Poulan/Crapsman clam shell spacers and bolts but the PR4218 was different.

Less than $20 in the saw but lots of labor time.
It's now a BIL loaner type. (maybe little too good for that)