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220 Gpu

B

BigMac

Member
I have a 220 that is pouring oil out of the blow by. The engine runs good and is strong . It smokes a little when you let it idle out the right side but not very much. Any ideas whats going on ?
 
YOU WONT GET A ANSWER! THIS WEEK END ! BUT THE GURU S WILL BE BACK IN TOUCH AFTER THE WEEK END ! HAVE A GOOD WEEK END ! :D AND WELCOME TO THE CLUB ! GLAD TO HAVE YOU ! :D ON BOTH OF YOUR THREADS !
 
when the last time you claened your oil screen might be cloged do you change yor oil reguler go get a leak down done cost aboat 35dallors this will tell whats up
 
This boat belongs to a friend I am sure he has never cleaned the screen out . I going to suggest that he give it a try . thanks alot
 
Did you just top it off with oil?

You may just want to have 10 quarts in it.
Many have told me they will spit all the extra oil out if you fill it more than that.

Also,
Does your crankcase breather come from the top rear of the crankcase, or the front?

Perhaps both.

Some say that you don't need to run the rearmost breather outlet.
They just block them off, cause they sling oil out bigtime from there.

Just some thought on it, I'm not the guru on anything.
Just trying to help.
 
It did have both but I blocked off the rear. I just spoke with him regarding the oil screen and as I suspected it has not been cleaned in about 8 years. Its really strange what happens when you dont take care of your equipment. thanks for the ideas
 
On a gpu you only want about 10qts. of oil in it. When filled up to the 12qt. full mark they tend to blow the 2qts. of oil right out of the breather in no time. Even if you have good leakdown numbers it could have worn out valve guides. Which is a common problem on gpu's, especially since they don't use valve guide seals. If the cylinders are fine it's not a big job to replace the guides and while your in there install some guide seals as well.

Larry
 
The best thing to do is a leak down test this is the best way to tell the condition of a motor. Jegs sells a good leak down tester cheap. I always put in 100Lbs of air and read your leaving pressure so if it's 90Lbs you have 10% leak down. I built a few 220GPU's and did a few tricks on the ring packages the rings sealed so much better then normal that when the piston went down in the bore it created so much vacuum it sucked all the oil thru the guides. So I installed a set of perfect circle valve seals on the motor and it quit sucking oil past the guides. 220 GPU's run so much stronger when you improve their ring seal issues!
 
Stock Continental GPU's have a steel bore cylinder. From sitting all the years until it was put on an airboat the cylinder walls get severly rusted. When the motor finally is run the rust is swept away and pitting remains. The pitting eats the rings up and causes blow by. Also with the carb on top I see a lot of motors sitting uncovered and it rains right down the carb into the motor. Causing rust. That being the reason there are so many .015 over Continentals. That back breather will work properly but you have to baffle the breather tube so the crank will not sling oil straight up the hole. If you have the back one blocked and you are pouring oil out the front then you have excessive blow by. You need to have a differential leak down test done. That will tell if you have a ring problem or a valve leaking. The only way to tell if you have bad guides is to pull a cylinder revove the valves and measure the guides.
 
I wanna thank Mike Thurman for his posts on these ole engines.

Its like going to school but also reiterates and confirms my long held feelings on how simple these things really are when compared to nearly any other recip engine.

Scotty
 
OK Listen to this I pulled all comp and leak down any where from 121 to 128 and 3% to 4.8 % leak down. Is that normal ? could there be a blockage on the return side for the oil ? Where can I buy a good rebuilt 220? Maybe I will take this one apart and try to fiqure it later
 
Sounds to me like those numbers are from a compression check and not a leak down test. There is a big difference. 80 psi source pressure is all that is needed to do and accurate leak down (differential pressure test). If you're not sure what the difference is, go to this link.http://www.wcengineering.com/articles/leakdown.html If those numbers are from a leak down, I'll shutup!!
 
Thats a really good web site to explain the difference. The thing is it seems my motor has good compression readings as well as leakdown numbers . I just dont understand whats going on . thanks for your help I will not GIVE UP!!!!
 
Hey Whitebear... Thanks for the Thanks. My dad had Airboat Headquarters for 30 years and I have been around Airboats since day one. I have seen a whole lot of motors move through the doors. From brand new boats to some that you could not even believe somebody would take to the woods. We have pretty much seen it all. I do not post here much but read a lot. But when I do post, I speak from experience. Anything I could ever do to help anybody, just ask. Thanks,
Mike
 
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