Author Topic: Leaking head  (Read 1323 times)

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stump43

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Leaking head
« on: July 14, 2007, 04:46:29 PM »
Question, I believe that the stud that holds one of the cam cradles is leaking oil out of the head via the helicoil that was installed. My guess was that it was cast and should have been drilled and tapped for a blind hole. When this was compromised the resultant leak started.

 Has anyone had to tackle a problem like this in the past and how did you do it? I'm going to machine a plug out of steel and screw it in with some jb weld on the outside thread.

Thanks in advance for your thought.

regards, steve.
maple falls wa

stump43

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Re: Leaking head
« Reply #1 on: July 21, 2007, 03:29:03 PM »
After doing some thinking about the leak, I'm beginning to think that the problem is probably the rubber/butyle oring disks that cover the holes under the cam towers. Does anyone have a fix for this? As the gasket kit came with some orings that weren't near the right size I'm guessing the supersport head is different in that respect also compared to the original design.
Or maybe I've just been snookered by the aftermarket gasket company again (won't be the first time). Has anyone just used Orings instead of the disks and gotten away with it. It's no big deal to pull the head as I modified the frame IOT work on the head at the track. 

Again I remain grateful for any insight experience on this subject. My first time around the block on the SOHC engine and I'm enjoying the work.

Thanks, steve. 

Offline scondon

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Re: Leaking head
« Reply #2 on: July 21, 2007, 04:09:16 PM »
Honda part # for those rubber "puck" seals is   91318-300-013

   The Supersport uses the same size as the K models so I would guess that the kit you got was a bit off. I would stick with the "pucks" rather than putting an open o-ring in there.

   Those cam tower bolts can strip out real easy and it is hard to get any real torque on them without stripping the threads in the head. Oil can seep under the cam towers fairly easily. I slathered a liberal amount of Hylomar sealant on the underside of the pucks in order to keep that oil from making its way outside the engine. 1000 miles so far and no hint of oil weeping.
Give me..a frame to build a bike on, and my imagination will build upon that frame

stump43

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Re: Leaking head
« Reply #3 on: July 23, 2007, 07:26:12 PM »
Thanks for the info. I guess I'll order the parts in the AM,  hopefully arriving in time for the weekend.

Best regards,
steve.

Offline MRieck

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Re: Leaking head
« Reply #4 on: July 23, 2007, 07:33:42 PM »
 Your point about a helicoil leaking is a good one.....I never really thought about it but it certainly could happen. Thanks.
Owner of the "Million Dollar CB"

Offline ofreen

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Re: Leaking head
« Reply #5 on: July 23, 2007, 10:18:04 PM »
I slathered a liberal amount of Hylomar sealant on the underside of the pucks in order to keep that oil from making its way outside the engine. 1000 miles so far and no hint of oil weeping.

I used Yamabond 4 on those seals 5 years and 26,000 miles ago and so far, so good.
Greg
'75 CB750F

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Offline rhinoracer

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Re: Leaking head
« Reply #6 on: July 23, 2007, 10:24:05 PM »
I stripped mine but repaired by tapping with a 1/4-fine thread, no helicoils. Thirty bucks for a set was too much cash for me, the 1/4" bolts hold just fine, I'm even thinking of changing the ones that are not stripped yet.

You should seal those threads or they will leak, I thought of teflon tape or liquid teflon pipe thread sealant, it is better suited for oil exposure than silicone sealant. I haven't finished my buildup yet so I can't say if it works.
Baja native.

stump43

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Re: Leaking head
« Reply #7 on: July 28, 2007, 12:09:40 PM »
yes I certainly do agree about the 30 smackers for a heli coil kit....there are cheaper options one shot inserts that are about 4.00 and use a 8 or 10 mm tap for the insert. I should have thought about the 1/4 fine option as I've gone the metric option for national  threads that  have stripped in the past. Thanks for the reminder. Still haven't found a round to it to get back to work on the bike. My daughters accord is killing me for quality motorcycle time.

Thanks you all very much for the tips and comments. I will report shortly on the results soonest.

regards, steve.

stump43

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Re: Leaking head
« Reply #8 on: August 11, 2007, 01:54:25 PM »
Well the way I fixed the problem with the leaking head was coat the old rubber disks with gasgacinch seems to be holding up well. I also droolled some on the stud. Oil tight so far. Thanks for everyones replies.

regards, steve