Pioneer/Partner p42hp build

[jacob j.]

Hi all,
Next question on a P42 rebuild. I pulled the top end off last night and it seems something made it's way into the cylinder and is now mashed into the upper chamber (See image 1) Also corresponding damage to the top of the piston (See image 3). Cylinder bore still seems ok, some scoring on the exhaust side. Circlips are both in and accounted for...anybody have any ideas from where a part might break off and find it's way in?

Bits of a rod bearing cage?

Yep, rod bearing cage or main bearing cage material. Those saws had metal cages in the main bearings from the factory. One may have broken loose just from years of wear and tear.

They're definitely worth rebuilding - they're tough machines.

 

[jbsaws75]

Bits of a rod bearing cage?

Yeah, could be. Case coming apart soon so I've have a good look at them. Thanks for the suggestion

 

[jbsaws75]

Hi all,

Sorry, next question. Seems like the oil pump drive gear is a press fit. What is the best way to remove it? Is there a special tool or can an adaptor be made for it?

 

[jacob j.]

I think I use a bearing separator on those, similar to this one:

https://www.ebay.com/itm/312320455591

 

[jbsaws75]

Thanks JJ. Ended up using a 1/2" brass gas fitting and a bearing puller (See on a utube video) Worked quite well.

 

[jbsaws75]

Hi All,

Quick question, are the ID tags on the case push studs or threaded? I wanted to remove them before painting the case.

Thanks.

 

[Junk Meister]

Not a whole lot really. The p40 and p41 have different ignition systems. There was early p40 and late with some minor differences. Good strong running 4 cube saw. They are a bottom fed quad transfer cylinder. Some of the p42 saws had the 6 transfer set up.

Did the minor differences on the early vs later P40 ignitions interchange without having to change flywheels? I assume the P41 saws used the same as the later P40 saws but the P42 saws were a (?2piece?)coil and required a different flywheel.
Refer to post #155 March 2020