QuestionQUESTION: I tried to make contact with you as I had in the past but all I was allowed to do was rate or thank you at the end of your last answer to me.
My friend pulled the piston out to look for possible cracks that would allow the crankcase to be pressurized and forcing the oil into the carb. He found nothing. He said he was stumped.
He doesn't have a cylinder leak down tester or a manometer.
The oil scraper ring was not abnormally worn.
The oil fill has a metal screw-on cap with a dip rod attached.
At the rate that the oil spits into the carb., it wouldn't take long to empty the crankcase and create a fog I could get lost in!
The new rings are what was available, don't know if they are chrome.
Hope this gets through to you,
Ray {:^)
ANSWER: Did you clean the crankcase breather and are the valve guides within spec? I've never seen valve guides wore enough to cause that much oil to get past them but it is possible. You can make a simple manometer out of vinyl tubing and a board.
Are you sure the scraper ring was not wore?
What is the engine model, type and code number?
Eric
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QUESTION: Hi Eric,
When the problem started, I cleaned the breather and it did not help. I put on a new breather and nothing changed. When I had my mechanic friend pick up the tractor, he put in a new breather, new rings and said the valve guides were good.
He said the oil rings were tight in the groove when he removed the piston but don't know if he was able to tell if they were worn beyond normal.
The Briggs engine model 320421, Type 0134-01, Code '71
My friend knows about the manometer but he said he knows there is no vacuum in the crankcase to measure, not the way the oil is coming out of the breather tube.
Ray {:^)
ANSWER: If there is no vacuum then there might be a gasket leaking. Were the piston rings staggered when they were installed?
To not have any crankcase vacuum is very rare. Are the crankshaft seals sealing? If there is no vacuum oil will typically come out the crankshaft seals and I have seen a couple of engine actually blow the seals out of the engine.
Have the crankcase seals been replaced?
It must be a rare engine as I can't find a parts list.
Eric
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QUESTION: Hi Eric,
We've been having trouble with our e-mail so I don't know if everything i sent got through to you.
(today is 1-27-12)
I just got off the phone with my mechanic friend and he said that he has talked with over twenty of his mechanic friends and they have never heard of having such a problem that couldn't be fixed by what has already been done.
My friend said he made a metal plate to cover the hole where the breather goes. He then pressurized the crankcase with 30 PSI and found no leakage anywhere.
I'm seriously thinking of replacing the engine before I put more money into parts and labor.
The engine is not rare but is old. Last made in 1971. If you go to the web site ereplacementparts.com and punch in the model and type numbers, there are exploded drawings and parts lists.
Sure hope you can help figure out this problem.
Ray {:^)
AnswerI have to agree with the other mechs. The engine should have crankcase vacuum based on what you have done.
While a new engine is a large initial investment I have found over the years it is often better, and cheaper, in the long run to just replace the whole eninge...I have many stories of projects that nickel and dimed me to death not to mention the frustration of trying to get them to run when I needed to use them.
I used to rebuild my own engines on my personal mowers but I've just replaced the whole engine on one of my Snappers a couple of years ago. The other mower is still running but the engine is old, early 80's, and is low on power. I'll use it for this mower season and just replace the engine next witer.
Eric
