Rebuilding G50b

[DialTone301]

Well I decided to pull the motor out of the SC and freshen it up.

The compression is only 105 and I suspect that I have a leak somewhere since the motor constantly has some oil around the crankcase on the clutch side. Might be the seal but I am also thinking one of the base gaskets is leaking a little.

Was going to check that everything was tight and found that one of the head bolts was stripped. I think now is the time to just pull the whole thing apart and check it out...hopefully the previous owner didn't strip out anything else.

[cj-ate]

G50B

Check the Articles section of the site. There is a G50B manual as well as a parts list. I printed a copy of the manual but it is very hard to read the adjustments section for some reason (all torque values ect). From what I can make out compression should be between 94-135lbs. I just tested my engine with a very cheap (not sure how accurate) Harbor Freight compression tester and it came out at about 95lbs. Seems low to me but the engine seams to run great. I did just replace the PTO side seal. Someone had put a Magneto side seal on the PTO side and the engine pushed it out. Seal sizes are Magneto side 30X50X8 and PTO side 30X62X10. From what I know Don is the man when it comes to the G50B or any two stroke for that matter.
Good Luck with the rebuild, Mike CJ-Ate

[DialTone301]

Thanks for the info CJ-ate. I am having a hard time reading that manual but I also didn't see the G50b listed.

It does appear that the head and base gaskets were leaking and I also suspect that the pto side seal is leaking. Cylinders look good..no scratches or any damage that I have seen. Everything is very gummy from whatever oil the previous owner was using.

I need to know what the cylinder to piston spec is and also the ring end gap. A list of all the torque values would be good too.

Where is a good place to get the proper clutch puller? None of the pullers I have were the proper one.

[DialTone301]

Can anyone confirm that the proper clutch puller is the same that is used for Arctic Cat hex shaft clutches? I find several places that say this is true but my cat puller does not work...it appears that the threads on the salsbury are further in from the outside....is there a bushing that comes out that would allow the puller to go deeper?

[DialTone301]

More info on my clutch. I took the large nut off and the nut is part of (for lack of a better explanation) a big bushing. I can see the end of the crank deep inside. I believe I can use a deep well socket as a spacer and then screw the nut/bushing back in to pull the clutch. Does this sound correct?

[DialTone301]

Got the clutch off...still have to find a flywheel puller.

Piston to cylinder clearance is about .006 but ring end gap is over .020.

[DialTone301]

Anyone have the torque specs for this motor??? I really would like to use the proper spec as I put it back together. Any help is greatly appreciated.

Jim

[George]

Anyone have the torque specs for this motor??? I really would like to use the proper spec as I put it back together. Any help is greatly appreciated.

Jim

Maybe this will help.

http://www.6x6world.com/forums/general-brochures-articles/5720-chaparral-engine-manual.html

[DialTone301]

Thanks George!

I saw this manual but since the G50b was not listed I was not sure if the specs were the same. Is it safe to assume then that this manual is okay for the G50b?

Thanks again
Jim

[DialTone301]

Thought I had a complete gasket and seal set...only had two seals and I need three. More parts to order.

I thought it was odd that I can not find a timing mark on the stator or the cases...I marked where the stator was and have to assume that it was correct. Does this sound right or am I missing something?

[George]

I've only had a G50B about a year now. I switched it over to CDI last summer. You might want to ask Don about timing on a points system.

[Don]

The specs for the G44B are the same as the 50, but I've never seen an engine without the timing marks on the flywheel and the fan cover. Sometimes they don't have the "F" marked, but there's always been a set of hash marks to line up. I don't think there'll be any markings on the stator plate with a point system.

[Don]

What's the third seal for?

[DialTone301]

In the removable cover on the clutch end there are two seals. An outer one that has a metal cover and an inner one that looks like the one on the mag side. Do I leave the metal one and just replace the other one?

I will look for the marks again. I have very limited experience with point systems everything I have ever owned had a CDI.

[Don]

Well, I've never seen one with a metal cover on it, so I can't say. The stock seals that I have for the engine are the same (except for size) on both ends of the crank. They've got a metal ring inside to fit the diameter of the outer bore with rubber molded around the whole assembly- looks like an oil seal on a four-stroke, more or less.