Jonsered 920/288XP piston compatability

[bama]

I got a 288xp piston from a member here to compare to the 920. It mounts with the same hardware and has the same stroke and bore. It is the same hight and the openings on the side of the piston are the same hight for each piston.

The 920 piston has a full skirt around the bottom of it while the 288xp piston does not. What else should I look for before I try this out?

Sorry if my terminology is incorrect. If I get time this morning, I will post a picture.

 

[bama]

Here is the picture. 920 piston is on the left.

One thing I just noticed is that the 288 piston is tighter against the crank counterweights. There is not as muchroom for tilting compared to the 920. Do I need to remove some of the skirt of the 288 piston or is this ok?

 

[gatkeper1]

Pardon me, but why not just get the correct piston for your 920.

 

[bama]

Pardon me, but why not just get the correct piston for your 920.

Parts are not made for this saw anymore, to my knowledge. I have only been able to find used parts when I have needed them. Maybe there is some NOS stuff around, but the piston/jug is what seems to disappear first.

It would also be neat to see if this worked.

 

[NWCS]

why not get an aftermarket piston on ebay? like this one right here:
http://cgi.ebay.com/Jonsered-920-93...ryZ85915QQssPageNameZWD1VQQrdZ1QQcmdZViewItem

 

[bama]

why not get an aftermarket piston on ebay? like this one right here:
http://cgi.ebay.com/Jonsered-920-93...ryZ85915QQssPageNameZWD1VQQrdZ1QQcmdZViewItem

Holy Crap! I was so sure that parts weren't made that I never even thought to check aftermarket for the 920. I was looking at a Golf for the 288XP to fit. No need to re-invent the wheel. I guess I better keep an "open" mind about parts availability! Thanks.

Just went on e-bay and bought one!

 

[NWCS]

there are more aftermarket parts coming out for older saws all the time, i hear Golf even has husky 2100 pistons. i just wish i could find one of them..

 

[rickyrooster]

jonsered 920 piston

http://cgi.ebay.com/Jonsered-920-93...itemZ7762693428QQcategoryZ85915QQcmdZViewItem this is a current ebay auction for a 920-930 jonsered piston. no need to rework something else. good luck rick!!!!!!!

 

[bama]

That is the one that Ben showed me. Bought it a few hours ago. Thanks. I never even thought to check if they were being made by anyone else.

 

[romad10]

DO NOT DO IT.. Just did it by accident... really bad stuff happened.. found out the hard way (by accident).. thought it was the correct piston only to find out it was not. it was in a box of unmarked pistons so my buddy grabbed a caliper and it was a 54mm. there was not a piston in the saw to compare it to so it has to work, right?

ended up ruining the crank/connecting rod bearing, Destroyed a good cylinder as well... crazy...

The height of the 288 piston is taller.
The distance from the top of the 288 to the center of the wrist pin is different than the 920
The 920 has a dual ring on it.

REALLY BAD STUFF will happen to your 288 or your JRED.. so DO NOT DO IT!

 

[romad10]

 

[nmurph]

This is an 8 year old thread. ..but thanks for the warning.

 

[LegDeLimber]

Ring locating pin(s) appear to be in different locations.
Can You give one of those photos in which the pistons are both slipped onto the the ends of a single wrist pin?
They both need to be oriented in the same direction, i.e exhaust or intake sides facing same way.
I Can't speak for others, but it helps my mushy little brain with comparing that height offsets.

also, bummer about your saw!

 

[towingace]

This is an 8 year old thread. ..but thanks for the warning.

LMAO...I didn't even notice, it was still a good read though. I think it's pretty cool when old threads are revived. Now I know why I couldn't see the OP's pics.

 

[pioneerguy600]

A good mechanic will check for skirt clearance from the crank and squish measurements before starting a saw with a swapped in piston. I have many saws out there running swapped in pistons with no issues because I altered the donor piston for crank clearance and adjusted the cylinder gasket for squish clearance. A piston with two rings will work equally well as a piston with one ring, that doesn`t matter as long as the ring ends are kept out of the exhaust port and the upper transfers. Many saws are out there running a two ring piston with just one ring installed, sometimes done to keep one of the ring ends out of a port, sometimes just because one ring causes less friction.

 

[towingace]

That 2-ring piston looks like it weighs a buttload more than the other one. I guess it probably wouldn't matter on a slow turner.

 

[romad10]

Huge weight difference for sure.

What does it matter how old a thread is? I think it is retarded when people make comments about it being old.

Is this site not about spreading information? Or is it only OK to open old threads if the queen of England says so.

The saw was not mine so I was not as upset had I had to pay for the parts and such. Now I get to split the case to replace the crank.

Ground hog day.

Sry for offending all of the "old thread" enforcers. I should probably be stoned for my offence. Much better than spreading information.

 

[Jacob J.]

How did the 920 piston ruin your crankshaft? Was the piston skirt contacting the crank somewhere? I'm thinking the big end rod bearing was already gone or on its' way out prior to installing the 920 piston.

 

[pioneerguy600]

The original piston is cut out to clear the crank counterweights whereas the full skirt piston was not, it would certainly contact the crank counterweights at BDC., the debris that caused would cause the scoring when it made its way up between the piston and cylinder wall.

 

[SawTroll]

....

What does it matter how old a thread is? I think it is retarded when people make comments about it being old.

.... .

It matters if it is a "what saw should I buy" thread - but not at all in a thread like this!