V2 Head Leaking

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The Nutty Professor

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Ok I've banged my head against the wall long enough trying to figure this out and I know I'm missing something dead simple. That being said I'm sitting there looking the motor over, up one side and down the other and I'm scratching my head still.

Here's the deal. The motor seems to be buttoned up tight. I used 1211 gasket on any place I suspected and some I didn't. What I'm getting is a high pressure leak. When the motor is running oil gushes from somewhere just under the V2 head near the exhaust outlet and gets up onto the spark plug? I'll be damn if I can find it. I would take photo's but I want someone to ask for them of a specific area first.
 
sounds like head gasket.... maybe you missed one of the locater dowls installing the head or something.... best thing to do it just pull the head off and check the gasket and seals between the head and barrel

high pressure oil would be coming from one of the headstuds
 
Locator dowel! Now that would make sense! That didn't even occur to me. I bet it's missing one I wasn't paying attention. I didn't take them off but I bet one fell out.
 
yep sounds about right..
there easily missed out which causes the head no to go on square.

also they known for squashing if they arent installed properly.. when this happens it actually stops the head from seating all the way..

remove the head and show us some pics mate..

it could also be a fractured oil line (the one going from the clutch cover to the head) or it could even be that you left out some of the alloy seating washers..

did you install the brass head bolt washer in the correct location?
check here for a pic of the location.. http://www.miniriders.com.au/motor-tutorials/28151-yx150-160-155z-top-end-build-up-magneto-mod.html
 
Washer is in the right place. It doesn't seem to be leaking from the head gasket that's dry or as dry as it can be after oil spraying everywhere.

The real Nutty Professor? Splain? From the movie of course not. From PM and MBN yes.
 
i had a very similar sounding problem on a 125 lifan copy the other week the oil leaked from bottom left looking at the head face on
the engine had to be removed to get the head gasket off so i cheated and just slid head and gasket back i noticed major deterioration of gasket around this point i tried to use some permaseal no3 and no 4 it slowed but didn't fix it

after removing engine from quad then removing head and gasket i got a proper look and found the seal that goes around the bottom left stud had deteriorated along with the head gasket after replacing seal and gasket bolted it back together and all fixed

I'm no mechanic but it sounds like the problem i had
 
Washer is in the right place. It doesn't seem to be leaking from the head gasket that's dry or as dry as it can be after oil spraying everywhere.

The real Nutty Professor? Splain? From the movie of course not. From PM and MBN yes.

As in Nutty Professor off DBW and FMX Aus? Maddo's mechanic.
 
On some V2 heads, the holes for the exhaust studs are drilled to deep and break through to the inside of the head. Oil escapes past the threads. Unscrew the studs and loctite them back in. Should fix it :)
 
Hi i have had exactlty the same problem with a stock head after I ported it. Definatly not blown head gasket. I figure the head is cracked somewhere letting oil escape from the gallery up into the spark plug area, then it runs down to the exuast pipe.
Otherwise it revs like a rocket. only loses about ten mils of oil for 10minutes riding.
Ride on. DD
 
Return feed banjo bolt not tight enough? Stud dowel slack/non existent? Damage Head, Lock tight/PTFE Tape the exhaust studs, Spark plug crush washer knackered?
 
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