Topic: Can a head gasket leak so bad it drips?

[Patrick]

I kind of at my wit's end and resigned to another teardown. It's my K0 750. It leaks oil. So badly now that after only a few miles when I put it on the kickstand the oil runs off the fins and puddles on the ground. It also collects on the crankcase below the carbs. I can't tell if it is leaking front and back or only on the front with the oil riding around on the fins. The bike was seemingly leak free when I first finished the resurrection last fall, but the problem is accelerating.

I have replaced the valve cover gasket with a Honda gasket (which is surprisingly easy with the motor in the frame), replaced the O-rings on valve inspection covers, retorqued the head bolts and replaced the sealing rubbers under the cam towers with new Honda seals. Still it leaks.

I am beginning to suspect a warped head, or perhaps a warped valve cover. But I have good, even compression and the damn bike starts easily, runs very well (kicks ass, actually) and idles like a new bike - smooth at 1,000 rpm.

The bike is bored to 810 cc and has a hot cam, if that matters.

Is there anything short of pulling the head that I have overlooked? I hate to buy a new head gasket unless I know it will solve the problem. Ever re-use a head gasket? This one has less than 400 miles on it.

Patrick

[tramp]

i would never reuse a head gasket
my guess is the headgasket is bad
you may not have torqued it to the right sequence
or it might need retorquing

[hymodyne]

Folks here have discussed coating gently used gaskets with a thin copper paint or coating; I've used a super thin coating  of hi-tech gasket in a tube with good sealing qualities, no more leaks, but upon inspection, the cam journals were shot on both my head and cam cover. I torqued to specs and used fresh oil every 500 or so miles, so I expect little pieces of my gasket fix getting clogged in oil passages contributed to their demise. If its warped, its probably just as well to get a new (to you) one here or  elsewhere.

hym

[Jerry Rxman Griffin aka MuthaF'er]

Not likely your head gasket in my opinion. How would that much oil get into the cylinder to leak without looking like you're fogging for mosquitos? In that case most would burn off rather than pour/leak out. More likely it's the rubber pucks under the cam towers, etc. My 810 is doing the same thing after maybe 10K hard miles. Do what I didn't know to do the last time - heavy duty studs. You might be able to reuse the head gasket - all depends. Especially if you don't damage it and go with new studs which will allow you to torque down more and squeeze that gasket more. The studs will only cost you a little more than a head gasket. If you replace the head gasket get an 836 gasket from Cometic. When you take the top off double check your torque before going farther to see if that might be an issue. 

[Patrick]

I forgot to mention in my original post, I have heavy duty studs and they are torqued to 20 pounds. I just doubled checked that two weekends ago when I pulled in the engine to put in the Honda sealing rubbers under the cam towers. I just can't figure out what else could be causing a leak without a bad head or valve cover.

Patrick

[dakeddie]

Hi Patrick,

Read this thread... http://forums.sohc4.net/index.php?topic=29992.msg309390#msg309390.  It explains my problem I had with my Wiseco 836.  I don't know about the 810 kit, but it might be the same thing.  Basically, I noticed my headgasket had oil return holes smaller than the stock gasket and that the dowel pins were bitting into the gasket.  I haven't had a trace of oil leaking yet, but I haven't put too many miles on since I put my engine back in either.  Time will tell, and I intend on posting my results at the end of the summer.

[Gamma]

Good Dakeddie,
I also cut the holes in the cometic gasket bigger the same as the original, and am eagerly awaiting you putting lots of miles on your bike

[MRieck]

 I just worked on an early head that required .012 off the top to be flat. The bottom had previously been milled but still required another .005 off it. They can "bow". When they are off that much you see some cam bind

[754]

Unless head and barrel are known to be flat, it may never seal..

[Patrick]

Sounds like my diagnosis is getting confirmed. The really sad part is there is only one local shop that machines old bikes. I know the guy who runs it and he has done really fine work for me on other bikes. He told me today he would mill the head and block for $50. The cost of a head gasket.

When I bought the bike it was in six plastic boxes and a bare frame. The head looked good. The cylinders had a fresh rebore and the pistons and rings were new. I somehow figured the PO would have taken care of the rest of the top end too.

There's an idiot in this saga somewhere. Now he gets to do it all over again.

Patrick