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Old 11-19-2017, 05:24 PM
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Default Found my oil leak - cylinder gasket

Finally found where my oil leak is coming from - see photo. Right at corner where cylinder gasket is. Pressure builds, air leaks out with oil, then pressure builds again. I want to check the torque on the bolts but can’t find them on this side where clutch cover is. Parts diagram show 2 bolts on other side.

Any idea where to look for the bolts? 1999 Magnum 500
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Old 11-19-2017, 06:17 PM
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2 of the 4 head bolts are on this side. Have to remove the rocker cover to access them.Not normally an area that would leak if torque sequence was followed correctly,but anythings possible. Trying to stop a leak now may be tough,but first thing is make sure the crank case in line filter and the hose isn't blocked and you can feel crank case pressure from the hose in the air box. Going back through the head bolt torque sequence many or may not help at this point,may take a new base gasket to solve it,but here goes from scratch:

Tighten the four larger bolts in a
crossing pattern evenly in the following steps. Mark
a line on the large bolts for a degree reference:
a. Tighten to 30 Nm (22 ft.-lb.).
b. Tighten to 70 Nm (51 ft .-lb.).
c. Loosen each of the four bolts exactly 180'
( 1/2 tum).
d. Loosen each of the four bolts again exactly
180' ( 1/2 tum) .
e. Tighten to 15 Nm ( 11 ft.-lb.).
f. Tighten each of the four bolts exactly 90' (1/4
turn).
g. Finally, tighten each of the four bolts exactly
90' (1/4 turn) more.
9. Tighten the two small 6 mm bolts *
to 8 Nm(71 in. lb.).

*There are two 6mm bolts visible(after you remove the cam sprocket cover) that tie the head to the cylinder and two 6mm bolts from the cylinder to the engine case.
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  #3  
Old 11-19-2017, 06:45 PM
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Got it - thank you as always. Will save for a weekend project.
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Old 11-19-2017, 08:26 PM
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My 1998 sp 500 leaks some in the same area- great idea to check the crankcase vent, that will be on my list. I tried JB weld on the seam but must have missed the leaking area. I checked the valve lash earlier this year, but didn't check all those bolts then. I took the front rack, plastics, handlebar and gas tank off, which was a fair amount to get to the valve cover.
Is that the best way to check those bolts or is there a better way?
Thanks!
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  #5  
Old 11-19-2017, 08:47 PM
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You don't have to go to all that trouble of removing all the plastic and tank. Just lift the rear of the tank enough to where you can get to the valve cover bolts. Once the valve cover is off the head bolts are easy to get to.
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  #6  
Old 11-19-2017, 09:50 PM
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Huge relief! Thanks for the experienced help again! I hope either possibility of vent or bolts is the fix for the leak!

Appreciate it!
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  #7  
Old 11-26-2017, 04:46 PM
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I followed all the steps, but still have the leak. It's very minor - should I just ignore it for now?

Can I replace the base gasket without pulling out the entire engine?
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Old 11-26-2017, 04:56 PM
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ENGINE
EH42PL/EH50PL Engine
Removal
The following components can be serviced or removed with the engine installed in the frame:
• PVT System
• Flywheel
• Alternator/Stator
• Starter Motor/Starter Drive
• Camshaft
Rocker Arms
Cam Chain and Sprockets
Cam Chain Tensioner and Guides
• Cylinder Head
• Cylinder
Piston/Rings

If it's just a small leak I'd just check oil level until you have a good time to work on it.. Plus by then you might want to check the piston/rings,valves for leakage,ect while you have it torn down.
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Old 11-26-2017, 05:46 PM
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Thanks again
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Old 11-27-2017, 12:27 AM
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Sorry if this is a dumb question - but can't I just pull the bottom cover off to get at the base gasket? Or do you have to tear down the entire engine from the top?
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