Stuck a piston

[ZUL8TR]

oil

Stuck the same motor only on a different piston.. Another motor just shut off and we don't know why.. Maybe fuel pump and the other motor was either to lean or got over heated.. I am running 8:1 oil

What brand and type oil are you using?

[PROPDOC]

I would double check your piston to cylinder wall clearances. Sounds like you might be a bit too tight, if you are having the same issue but different cylinder.....

[DiGia54D]

Mike, sent you the info in your PM

[blueskyracer]

I am about to put std pistons in the 1st over holes!!! Thanks Wayne for the contact info

[Dave M]

Check it

You better get a bore indicator and check for straight, in addition to checking clearances. That stuff happens for a reason, something is not right.

Along the same line as Mike F. was saying, it could be water. Are you running any particular theroy on your water routes inside the engine ? Is the fitting big enough ? Is the hose leading from gearbox to the engine bent so it kinks somewhat ? Is your tie down rope kinking the water line when you turn ? Are you letting out to much water at the top of the block ?

Sounds like your fuel/oil ratio is okay, how about jetting on each carb ? Did you get a good plug read ?

Sorry you are having issues, I know it sucks. I have had my fair share this year.

[Rex Hall]

Cam grind

Usually when you stick only at the wrist pin side of the piston, you do not have enough cam grind, or clearance above the wrist pin. Your skirts and intake and exhaust side of the piston looks like it was not rubbing at all, and not enough ring clearance will not stick the piston, just break the ring. You need the right clearance on the skirt to get good crankcase compression, but you need extra clearance at the wrist pin and above to let the piston grow. They always expand more at the wrist pin than anywhere else.

[boatracer69r]

I am about to put std pistons in the 1st over holes!!! Thanks Wayne for the contact info

Hey mike, I've done that on accident...once

[blueskyracer]

Hey mike, I've done that on accident...once

I bet they did not stick.. I will be contacting folks that offered as soon as we find out what is up with our 12 year old Lab.. He is having serious problems

[Dave M]

Prayers

I bet they did not stick.. I will be contacting folks that offered as soon as we find out what is up with our 12 year old Lab.. He is having serious problems

Sent my prayers for him, poor puppy. Get him well again, I have to see him in Trout Creek next year !

[blueskyracer]

Sent my prayers for him, poor puppy. Get him well again, I have to see him in Trout Creek next year !

Sorry Dave but we had to put Mo down last night.. With the blown motors and now this it has been a terrible week so far..

[ZUL8TR]

Your friend

Sorry Dave but we had to put Mo down last night.. With the blown motors and now this it has been a terrible week so far..

Sorry to hear about your friend Mo, loosing a family friend is not easy. Prayers for your family and Mo.

[Dave M]

Sorry

Sorry Dave but we had to put Mo down last night.. With the blown motors and now this it has been a terrible week so far..

Mike/Teresa,

I am sorry. I know how much our pets are a member of the family. I will be thinking of you guys.

Dave

[blueskyracer]

well trying to get use to a empty house I went and worked on motors.. Got the stuck piston one apart and I was right it was number two this time.. I did some measuring of the bores and they all seem to be 2.579-2.580 and the pistons measure 2.575 at the skirt and 2.571 at the piston pin boss area.. My question is can I hone out a thousandth or two to give more clearance..

I did a compression check on the motor the daughter was running and suddenly shut down.. Cylinder one was 120, cylinder two was 50, cylinder 3 was 120, and cylinder four was 65.. I guess I will be tearing down another engine..

At least engine number three is all 125 for compression but it got very hot when I shut it down and was really surging so I am glad I shut it down and got to use the tow rope again.. That one I think I lost the water pump so that's another repair.

[PRO-MOTIONRACING]

This is an area I have given some thought to and I am going to try two things...
First I plan a slight to hone the pin area in the piston. Even though this is a roller bearing pin my thought would be perhaps a little looser fit between the pin and piston might help with heat dissipation. My local machine shop can not hone a hole this small so I will be using a piece of emery cloth in a cloth holder from a gun cleaning kit and a drill motor.
Second I plan to hand sand the sides of the piston in the pin area.

Also I drill very small holes in the water jackets on the fuel pump side of the motor. This makes certain that I have good circulation and makes a cool sprinkler effect at the beach.

50-R

[Larry M]

This is an area I have given some thought to and I am going to try two things...
First I plan a slight to hone the pin area in the piston. Even though this is a roller bearing pin my thought would be perhaps a little looser fit between the pin and piston might help with heat dissipation. My local machine shop can not hone a hole this small so I will be using a piece of emery cloth in a cloth holder from a gun cleaning kit and a drill motor.
Second I plan to hand sand the sides of the piston in the pin area.

Also I drill very small holes in the water jackets on the fuel pump side of the motor. This makes certain that I have good circulation and makes a cool sprinkler effect at the beach.

50-R

I would chuck up the wrist pin in a lathe and emery cloth it if I wanted a little more clearance in the wrist pin bearings. I think it would be a lot easier.
Larry Mac