Author Topic: Seeking tips on oil leaks from valve cover.  (Read 181 times)

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Offline juntjoo

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Seeking tips on oil leaks from valve cover.
« on: January 08, 2019, 02:16:05 pm »
I've got leaks coming from a valve adjustment cover and around the main valve cover gasket. All the gaskets, 4 total, are recently new within the past year but I've taken the covers off a few times.

Does this happen naturally after you've removed the covers?

Also, I didn't use any RTV for the main cover. I tried tightening the bolts a bit beyond the "6-9lb/sf" spec which helped a bit but I doubt that's a good idea, especially after I've had to recently repair a couple threads in the cylinder head, not from over torqing the bolts myself that I recall. Does this just happen over numerous removing and re-torqing with aluminum?

Should I try again with some rtv for the main cover(not adjustment covers)? I do have a fresh set of gaskets but if I don't need to use them I'd rather save them. Thanks
« Last Edit: January 08, 2019, 02:18:16 pm by juntjoo »
-Ben

82 Nighthawk 650

I just wanted to own and ride a bike. instead I became a (amateur)mechanic.

Offline robvangulik

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Re: Seeking tips on oil leaks from valve cover.
« Reply #1 on: January 08, 2019, 04:11:08 pm »
Why do you want to save those fresh gaskets?
For when your bike might leak?
You're there already..... 8)

Offline mrbreeze

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Re: Seeking tips on oil leaks from valve cover.
« Reply #2 on: January 08, 2019, 06:19:47 pm »
You don't want to use rtv anywhere on your bike. That crap has a bad habit of making it's way to the oil nozzle that supplies oil to your top end.
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Offline juntjoo

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Re: Seeking tips on oil leaks from valve cover.
« Reply #3 on: January 08, 2019, 06:37:17 pm »
Why do you want to save those fresh gaskets?
For when your bike might leak?
You're there already..... 8)

Above I asked

"Does this happen naturally after you've removed the covers?"

I don't k ow the answer. If not, then it's something else that is causing the leaks and using the fresh ones would be a waste. After going in under the head cover a couple times is it normal for the gasket to lose it's effectiveness?

And what about for just the adjustment covers? How many times should you be able to open those up without having to replace the gaskets? Thanks
-Ben

82 Nighthawk 650

I just wanted to own and ride a bike. instead I became a (amateur)mechanic.

Offline juntjoo

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Re: Seeking tips on oil leaks from valve cover.
« Reply #4 on: January 08, 2019, 06:43:12 pm »
You don't want to use rtv anywhere on your bike. That crap has a bad habit of making it's way to the oil nozzle that supplies oil to your top end.

I know what you're talking about. A mechanic used it on my bike and made a mess. I DO have to use a bit at certain spots where I scratched the aluminum back when I didn't know better, before I had a manual and pryed on the cover. But I make sure to use just enough on the outside of the gasket.

BTW can you resurface the top of the head at all? Is there enough room for one go? I don't think I need it for the couple scratches I made but just curious
-Ben

82 Nighthawk 650

I just wanted to own and ride a bike. instead I became a (amateur)mechanic.

Offline bryanj

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Re: Seeking tips on oil leaks from valve cover.
« Reply #5 on: January 09, 2019, 03:56:59 am »
O ring between valve cover and head should only be used once, those on tappet caps change when they are "flat" to look at. RTV never
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline juntjoo

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Re: Seeking tips on oil leaks from valve cover.
« Reply #6 on: January 09, 2019, 04:03:00 am »
O ring between valve cover and head should only be used once, those on tappet caps change when they are "flat" to look at. RTV never

I guess we have different heads cuz I don't have o-rings there, I have these disk shaped ones though
-Ben

82 Nighthawk 650

I just wanted to own and ride a bike. instead I became a (amateur)mechanic.

Offline Scott S

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Re: Seeking tips on oil leaks from valve cover.
« Reply #7 on: January 09, 2019, 04:20:47 am »
 He's just referring to the shaped gaskets for the valve inspection caps. The 500/550 use O-rings, the 650 has shaped gaskets. Same function.

 Replace valve cover gasket every time. Valve inspection caps can be re-used several times.

 No RTV, anywhere, ever. It's just a band-aid for another problem. If you MUST use anything, get some Yamabond or 3-Bond and use SPARINGLY. Just a thin smear, not enough to squeeze into the head or oil galleys.

 Unfortunately, it looks like the shop that caused your issues before is still causing issues. Try using a straight edge on the valve cover and make sure it's not warped.
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Offline juntjoo

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Re: Seeking tips on oil leaks from valve cover.
« Reply #8 on: January 09, 2019, 04:45:13 am »
He's just referring to the shaped gaskets for the valve inspection caps. The 500/550 use O-rings, the 650 has shaped gaskets. Same function.

 Replace valve cover gasket every time. Valve inspection caps can be re-used several times.

 No RTV, anywhere, ever. It's just a band-aid for another problem. If you MUST use anything, get some Yamabond or 3-Bond and use SPARINGLY. Just a thin smear, not enough to squeeze into the head or oil galleys.

 Unfortunately, it looks like the shop that caused your issues before is still causing issues. Try using a straight edge on the valve cover and make sure it's not warped.

Thanks!
-Ben

82 Nighthawk 650

I just wanted to own and ride a bike. instead I became a (amateur)mechanic.

Offline DaveBarbier

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Re: Seeking tips on oil leaks from valve cover.
« Reply #9 on: January 09, 2019, 04:52:10 am »
If the valve inspection gaskets are leaking I’d suggest new ones that are soft and will conform better. Those you can use many times without issue. I got some from 4into1 and they were a little small. I had to stretch them to get into the cap and quickly screw them to the valve cover. They’ve been fine though. I remember looking for OEM ones and they were very hard to find...back when I  was looking. I think at that time only the right one was available.

The shaped round valve cover gasket (still called an o-ring because the O refers to the cross section shape not whether it’s in the shape of a circle) might be aftermarket and thinner than it should be. You could get an OEM which will be the proper thickness. Do NOT tighten the valve cover more to try and get more squeeze out of it.

Offline juntjoo

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Re: Seeking tips on oil leaks from valve cover.
« Reply #10 on: January 09, 2019, 04:58:21 am »
If the valve inspection gaskets are leaking I’d suggest new ones that are soft and will conform better. Those you can use many times without issue. I got some from 4into1 and they were a little small. I had to stretch them to get into the cap and quickly screw them to the valve cover. They’ve been fine though. I remember looking for OEM ones and they were very hard to find...back when I  was looking. I think at that time only the right one was available.

The shaped round valve cover gasket (still called an o-ring because the O refers to the cross section shape not whether it’s in the shape of a circle) might be aftermarket and thinner than it should be. You could get an OEM which will be the proper thickness. Do NOT tighten the valve cover more to try and get more squeeze out of it.

Thank you. God to know. Yeah, mine are after market. And I thought the adjustment cover ones would last longer. God to hear you shouldn't ever go over spec on torqing. I figured but tok a little chance anyway. Not too far but I won't do that again. OEM seems to be better on all rubbers I'm learning. This is the most I've ver dealt with rubber and aluminum, but glad I'm figuring it out finally. Don't like dealing with oil leaking on my shoes/boots.
-Ben

82 Nighthawk 650

I just wanted to own and ride a bike. instead I became a (amateur)mechanic.

Offline bryanj

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Re: Seeking tips on oil leaks from valve cover.
« Reply #11 on: January 09, 2019, 06:32:25 am »
Yes i meant O ring as in cross section not in shape of groove.
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline mrbreeze

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Re: Seeking tips on oil leaks from valve cover.
« Reply #12 on: January 09, 2019, 03:21:22 pm »
I just went back through this thread to see what bike you had. Yours is a 650? I don't know anything about 650's but I know on a 750 if your cam pucks are bad it can mimic a leaky valve cover. You may want to look into that. Someone here should chime in with some info for you. As already mentioned...stay clear of RTV and don't over torque anything. Aluminum threads are very unforgiving!!
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Offline juntjoo

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Re: Seeking tips on oil leaks from valve cover.
« Reply #13 on: January 09, 2019, 08:04:55 pm »
I just went back through this thread to see what bike you had. Yours is a 650? I don't know anything about 650's but I know on a 750 if your cam pucks are bad it can mimic a leaky valve cover. You may want to look into that. Someone here should chime in with some info for you. As already mentioned...stay clear of RTV and don't over torque anything. Aluminum threads are very unforgiving!!

Yes! I've learned. Had to repair two threads in my head. Wasn't easy and those heli coil kits with their proprietary tools aren't cheap. $30 a size for one brand, "OEM", $45 for the original brand with with the better (skinny/tighter fit) tool. I needed the $45 one.

Where do those Puck gaskets leak from? The fins? As far as I can tell the system is closed except for any leaks around the other regular gaskets. I have a set of those too. Maybe while I'm in there I should do those too. Not like I could just easily try without replacing them then go back in if need be later. Only one shot to get them all. I just hate the idea of wasting perfectly good ones
-Ben

82 Nighthawk 650

I just wanted to own and ride a bike. instead I became a (amateur)mechanic.

 

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