17.5 Briggs and Stratton Major issue

christophert

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A 17.5 Briggs and Stratton came into the shop I am employed at. The previous mechanic has done an extensive amount of work on the engine (over $600.00 for parts and labor) and yet it still has issues. It seems after the last mechanic put it back together, it started pumping oil up the line towards the fuel pump. He put a fuel filter in the line to slow it down, but nevertheless it would literally pump all the oil out as it ran. I did a compression check and found it was losing compression. Upon tearing the top end down, I found it had a blown head gasket. I replaced the head gasket, cleaned everything up, and put the engine back together. Now....it is pumping the oil at a much slower rate, but nevertheless it is still pumping oil up towards the fuel pump. What are some more options?
 

ILENGINE

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Make sure the breather system is actually allowing crankcase pressure to escape from the engine, Feel for pulses blowing out when the engine is running, Barring that i suspect that either the head, or the associated cylinder surface is warped preventing the head gasket from sealing.
 

christophert

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When I had the head off, I checked the block with a straight edge and it seemed to be flat (but my eyes aren't the best in the world). I'll check the crankcase breather (thanks, hadn't thought of that). The poor owner has paid out more in parts and labor than a new engine would've cost. Thank you for the input!
 

ILENGINE

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I was thinking the same thing. the guy could of dropped a new engine on that mower for what he has in repairs.
 

bertsmobile1

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I fit either Stens or copper head gaskets on Inteks as the B & S gasket is a touch on the poor side.
The important place is the bridge between the bore & the pushrod tunnel.
I stone them with a 10" water stone and when I do you immediatly see that the face is cut with a flycutter and quite rough.
many times there are milling troughs right through that area where the gaskets blow.
 
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