wrist pin bearings ? 770

engr146 · 02-17-2010, 01:42 PM

I see wrist pin bearings for a TS770 But on piston replacement kits they only state piston ,rings and circlips.
I have to replace PTO piston ,Do I need to buy wrist pin bearing also.they don't mention them in the replacement kits.

engr146 · 02-18-2010, 06:40 PM

Quote:

Originally Posted by engr146

I see wrist pin bearings for a TS770 But on piston replacement kits they only state piston ,rings and circlips.
I have to replace PTO piston ,Do I need to buy wrist pin bearing also.they don't mention them in the replacement kits.

I don't know why SBT Lists them !!! If you don't need them, I just want to make sure ,I get everything needed in 1 order Shipping Fee's

QuinnO · 02-19-2010, 07:15 PM

Are you just replacing it for the hell of it or did it fail? If you are going to put a new slug in there with out boring it it will rattle the skirt in the bore & the intake window will brake off and blow up again very quick.

If it was blown up that way and the rear piston skirts broke off, there is a hole in the lower case half most of the time.

engr146 · 02-20-2010, 12:13 PM

Bad carb +bad carb gasket ,caused holed pto piston,cylinders are perfect, 150# in mag cylinder,I'am just replacing .50 piston to match exsisting .50 piston.
Holed piston has no damage other than hole from lean detonation.

QuinnO · 02-20-2010, 01:35 PM

OK thats cool then, I just didnt want to see you spend the money to do 50% top end, then have it still run bad.
90% of the time the PTO piston just gets worn and walks side to side in the bore. The skirt brakes off , the chunks get inbetween the crank and case and lock up or blow a hole in the lower case half. I have a Shark engine out right now for the same thing.

engr146 · 02-21-2010, 07:37 AM

You and I have conversed before about my TSL770 I also live in Mass. ,I have the cylinder studs soaking rite know,Haveing a hard time pulling head off lower end,without getting ruff with it.I'm going to try again this week.
Atleast know I can order Pison and topend gasket kit
,
Do you know what gasket sealer I should use if any. Base ,Head.exaust,carbs

dank · 02-21-2010, 09:59 AM

SBT will give you the wrist pin bearings with a top end kit if you ask. The are packages with the crank/rods normaly.

engr146 · 02-21-2010, 11:30 AM

Do I need to replace wristpin bearings ,when just replacing a single piston.
also need info on were and what kind of gasket sealer to use.on gaskets.

QuinnO · 02-21-2010, 01:49 PM

,
Do you know what gasket sealer I should use if any. Base ,Head.exaust,carbs[/QUOTE]

I use copper spry tack on the head, not the base that I just clean and use hi temp silicone. (just a little) to coat one side so the jug will have the base gasket stuck to the bottom of the jug or the engine. You should use so little you cant see it squeeze out when you tighten it down.

You will get a lot of opinions on this. I wrenched professionally for 15 years and it did well by me. I did not get "comebacks" so you decide how you want to do it.
You can use no sealer if you like, a touch of sealer is cheep insurance of no leaks.

engr146 · 02-21-2010, 02:40 PM

When I pulled exaust ,there was no gasket ,pre-owner just used Hi heat silicone form a gasket,I will use what you recommend.
I want to do new gaskets rite ,
THX