hanko

Run Lawn Boy 150:1. No Dont

Bill Rademacher

My Feedback: (77)

I finally got a chance to run the motor. We have been swamped with rain here in KY.

It fired right up and runs like a scalded dog. Unbelievable!

thanks Ralph!

Billrad

spaceworm

How do you account for the fact that it ran before you replaced the backplate, then didn't. But, now runs ok with just a ring replacement?
As the thread title says: this is still a mystery. Can you help all of us that tried to help you out with some more clues? Thanks.

Sincerely, Richard

captinjohn

I think he said the engine mount holes was drilled out....not sure.

captinjohn

first page...quote
<hr />It ran beautifully until I put it on a different airframe...in doing so I decided to replace the rear crankcase, since I bought it used and the three threaded mounting lugs were drilled out.

w8ye

My Feedback: (16)

This engine most likely had compression in the previous airplane.

But when the owner disassembled the engine to change the crankcase, he must have desturbed the ring postion in the cylinder because when Ralph got the engine, it didn't have enough compression to start. An old ring will sometimes do that if it gets mismatched in the cylinder.

Bill Rademacher

My Feedback: (77)

Yep, that seems to be what happened.

All I know is it wouldn't start after I replaced the rear crankcase half, keeping the same bearings.

I was careful not to break the ring (been there, done that) but I guess misalignment is the story.

That's all I really know. I learned something new! I would have never figured on the ring.


I unwrapped it, bolted it up and bolted the muffler on, primed it and away she went.


billrad

Lnewqban

The engine may be running strong, but the previous problem will remain a mystery.
This puzzle has missing parts.

Bill Rademacher

My Feedback: (77)

well, I'm sorry I don't know what missing puzzle parts are. I'm just glad it is fixed.

billrad

Antique

My Feedback: (4)

No missing parts. I just replaced the ring....Saw this on a few G38 in the past....