850 Thru Bolts

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splatt

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Has anybody had oilleak up the thru bolts and out between the cyl & head, is the washer under the bolt ment to be an alloy washer? and act as a seal.
I recall when I had the barrells off they where alloy but all munted so I made some up out of steel thinking that would stop the crushing problem.It's been wet around the area under the ex pipe for about 2 1/2 years , fairly sure I loctited the 2 front studs back in to eliminate that leak....
 
If you're talking about the long Allen bolts on an 850, the thick 3/8" washers are steel. And no, I've never had oil leak from there. However, the 2 studs in the front of the head (9 & 10 in the sequence) often break into the pushrod tunnels and will leak out around the head gasket up front. Lots of threads here about that...
 
splatt said:
Has anybody had oilleak up the thru bolts and out between the cyl & head, is the washer under the bolt ment to be an alloy washer? and act as a seal.
Click to expand...

The four long Allen bolts screw into blind holes in the crankcase if I remember correctly, so theoretically the oil should not be able to travel up them to the head joint-unless perhaps it was getting to the bolt drillings at the crankcase joint?
 
Sorry ...what is munted, this sounds like a leaky head gasket,especially if some steel spigot thing was made there. Pull the head,inspect gasket for leakage point/s all over the place . Probably not the long bolts at all. Try a copper head gasket with copper RTV light smear to ulta clean surfaces (brake cleanered and wiped ).
 
Gracias amigo ,having a taste of my new vino nuevo batch, next step stupido ! 850 thru- bolt washers easily crushed - chewed up when reused , yes they are steel.
 
Always put a dab of silicon on the front two nuts to stop oil leaks from studs and after you've re torqued the head after a few heat cycles don't torque them again or seal will be broken!
 
Had to have a chuckle at description 19,when it first started I suspected a head gasket leak, but that was over 15000km ago so sort of eliminated that, I thought the oil could be going between the barrell and crankcase, finding it's way up the stud, and weeping out, either way head has to come off to fix.

No ugly spiggot made just steel washers, and the other 2 studs are dry.
 
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