LegendsRacer - Legends & Bandolero Racing Forum
LEGENDS => Engine Care & Tuning => Topic started by: ZForceRacing01 on March 26, 2015, 08:11:26 am
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Anyone ever have trouble with their valve cover leaking? I had to replace several of the green seals but that is not the issue. I have a leak on the exhaust side valve cover on the both interior and exterior sides. Not sure of the cylinder sequences but it’s the two cylinders closest to the fire wall. The exterior seems to be worse than interior.
The valve cover bolts are at 100 inch pounds. I figure the gasket needs replacing with is my intended course of action tomorrow morning. I am supposed to run my first race tomorrow night so I am hoping this would fix the problem.
Funny thing is I don't see valve cover gasket on US Legends parts list.
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Yamaha calls it a "head cover gasket".
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You might want to check your cam journal bolts. I had a valve cover leaking because one of the cam journal bolts was sheared off (fresh from INEX rebuild). Since the valve cover bolts to the cam journals, it was never tightening it down enough to seal the gasket. I had an oil fire on track because the leaking oil puked onto the headers.
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Seems similar to my problem. Thanks.
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Can I pull those cam journal bolts one at a time to check them without messing up can timing?
What is the torque spec?
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This is where I have to bite my tongue. :P
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Can I pull those cam journal bolts one at a time to check them without messing up can timing?
What is the torque spec?
You can pull both bolts on a journal and inspect the journal. The other 3 journals will hold it in place.
As far as torque, I do not remember. I have it written down somewhere, but can't seem to find it. Off the top of my head, the numbers 12 ft/lbs or 144 in/lbs keep popping in there, but don't quote me. Ask around, someone will know. I think I had gotten my info from Curt Andrews when I was dealing with the issue.
Don't be surprised if you have to helicoil some of the threads in the journals, I replaced the sheared bolt and fixed 3 sets of threads in the journals.
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Torque spec's for the cam caps is 8.7 ft-lbs per the Haynes manual (Section 2, page 3)with the following caution noted (Section 2, page 11):
"Caution: Tighten the no. 2, then the no. 4, then the no. 1 bearing caps evenly to specifications in that order, then tighten the no. 3 caps to specifications. Otherwise the no.3 caps may be damaged. While tightening, DO NOT let the camshafts rotate!"
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Torque spec's for the cam caps is 8.7 ft-lbs per the Haynes manual (Section 2, page 3)with the following caution noted (Section 2, page 11):
"Caution: Tighten the no. 2, then the no. 4, then the no. 1 bearing caps evenly to specifications in that order, then tighten the no. 3 caps to specifications. Otherwise the no.3 caps may be damaged. While tightening, DO NOT let the camshafts rotate!"
+1 Jim.
I had faith someone would be on top of it...
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RPM has the genuine Yamaha valve cover and green bolt seals in stock.
Valve Cover Gasket (http://www.rpmracingca.com/proddetail.asp?prod=Head%3AV%2FCGasket)
XJR1300 Grommet (http://www.rpmracingca.com/proddetail.asp?prod=Head%3AXJGROM)
Also, if the head is cracked at the cam boss of the head it will continue to leak. Here is a picture of one that I am currently building that has already been repaired.
(http://i1215.photobucket.com/albums/cc517/racerrad8/008_zpsagzsgmxf.jpg) (http://s1215.photobucket.com/user/racerrad8/media/008_zpsagzsgmxf.jpg.html)
Randy - RPM
www.RPMracingCa.com
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So I do have an issue with a cam journal bolt. Exhaust side #2 cylinder, the cap with three bolts. The odd one close to the chain is the issue. The bolt is not sheared, but is just bottomed out and spins. There was some threads on it when I pulled out.
Is there a steal sleeve down there or are you scewing into aluminum? Wondering if I can tap it and put a little bigger bolt in there?
Btw Randy this head has been repaired before, big Custer of weld in the same spot, not quite as pretty as yours.
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You will need to drill out, tap and install helicoil to properly repair. I had to do this once myself on 2-3 of same fasteners on an engine.
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That seems to be the route we must go. Watched a youtube video, don't look too difficult.
Or maybe we could go with the next size up bolt. Tap that in.
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Trust me, use the helicoil to repair. Helicoil thread is actual stronger than virgin aluminum original threads. I've seen many threads repaired in aluminum engine blocks, heads, etc.
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I agree with Mark. Use the helicoil.
Steve
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Ok, thanks.
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Ok, where do I get a replacement Csm journal bolt? I have looked everywhere!
Calling US legends in the morning though. They better have it.
Really pissing me off I have to got to them for damn near everything.
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I have plenty, that I can send you for the price of shipping.
Shoot me an email and I can get them to you early next week.
Randy - RPM
randy@rpmracingca.com
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I spoke to Bryan in the engine shop. I got it covered, thanks Randy. I will remember your offer to help in the future.
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Just an update Helicoil installed. If it ever quits raining and the tracks quit weeping I may be able to race the damn thing and let you all know how it all turned out.
Been rained out all but two weeks this season, I had to work both of those weekends.
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So Valve cover leak endeavors continue. There is a visible leak on the exhaust side near the cam boss.
This head has been repaired, although I have been told work doesn't look all that great. I don't know It just seems they put a lot of weld on there. Though there does not seem to be a problem with the integrity of the weld.
Oil just seeps from under the gasket. A little seeps onto the header and will smoke, but not really notable until after the race. A little will get on the fender. Some of my competitors have expressed interest but have not complained, the track hasn't said anything so I keep racing.
it has got better since I put the helicoil in. My crew chief say lets crank down on the valve cover bolts some more. But cranking down on the valve cover bolts means upward pressure on the cam caps and pulling on those aluminum threads in the head. Already been that route once.
We tried some high temp RTV but it didn't stick. Someone told me of some type of Copper something or another RTV that works real well, but I forgot the whole name.
I think who ever fixed the head didn't do a good job resurfacing where the gasket meets and that good be the problem, even though it look fine looking at it.
Anyone have any ideas?
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put some heat on your head and most likely you find a small hairline crack. These heads are famous for doing this and it will make you think it is the gasket. That is why most of the motors have a plate welded on the cam chain area of the head.
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Oil just seeps from under the gasket. A little seeps onto the header and will smoke, but not really notable until after the race. A little will get on the fender. Some of my competitors have expressed interest but have not complained, the track hasn't said anything so I keep racing.
Please get it fixed. I though mine was just a little leak also.... until....