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-   -   Valve cover spreader bar (https://67-72chevytrucks.com/vboard/showthread.php?t=652541)

domano 68 12-10-2014 08:19 PM

Valve cover spreader bar
 
Changing out my valve cover gaskets to Fel-pro rubber gaskets with metal core due to a leak. The covers are aftermarket Chevrolet stamped chrome. The spreader bars under the bolt were quite short. The ones that came with the gaskets are a bit longer. I also have a set of longer ones.

Wondering which ones to use? Good, bad, suggestions please.

http://i148.photobucket.com/albums/s...ps9cf64bfa.jpg

hugger6933 12-10-2014 08:50 PM

Re: Valve cover spreader bar
 
Use the longer ones just don't tighten them down too tight, also check the valve covers I 've seen many many times leaks at the bolt hole from the hole it self being distorted because of bolt tighting being too great. If that is your case time to do a little hammer work on them ever so lightly to smooth out the hole so that it is like it should be. Jim

hotrodder 12-10-2014 09:14 PM

Re: Valve cover spreader bar
 
put a little RTV on the threads, works great.

Lattimer 12-11-2014 12:16 AM

Re: Valve cover spreader bar
 
In my experience the longer ones seal better. More surface area and they have a bend to them so they act like a spring and keep tension on the cover.

domano 68 12-11-2014 12:17 AM

Re: Valve cover spreader bar
 
Using the longer ones, I assume the humps at the ends are installed touching the valve covers? TIA!

BLT gmc 12-11-2014 10:23 AM

Re: Valve cover spreader bar
 
I must recommend the long ones and yes the bump goes toward the cover. Bruce

MARKDTN 12-11-2014 12:00 PM

Re: Valve cover spreader bar
 
Quote:

Originally Posted by Lattimer (Post 6953044)
In my experience the longer ones seal better. More surface area and they have a bend to them so they act like a spring and keep tension on the cover.

I agree

cdowns 12-11-2014 12:16 PM

Re: Valve cover spreader bar
 
if the valve covers are bent it is going to leak

Lou Boffa 12-11-2014 03:31 PM

Re: Valve cover spreader bar
 
1 Attachment(s)
I used the longer ones. Always had problems with the short stock ones.

OregonNed 12-11-2014 03:57 PM

Re: Valve cover spreader bar
 
I used the longer ones, and it is amazing how a light torque will cure oil leak issues...

mechanicalman 12-11-2014 08:56 PM

Re: Valve cover spreader bar
 
Subscribing, want to see how the rubber/metal gaskets seal against the rough surface of the stock style small block head.

domano 68 12-11-2014 10:15 PM

Re: Valve cover spreader bar
 
One of the longer spreader bars prevented one of the bolts from threading well so I used the medium ones. I believe I got the leak fixed. I did use the Felpro rubber gasket with steel core and no RTV. My valve covers are chrome aftermarket from Chevrolet Performance Parts.

BLT gmc 12-12-2014 10:45 AM

Re: Valve cover spreader bar
 
mechanicalman, I have used a flap wheel on a side arm grinder and LIGHTLY polished that entire rough surface. I must say it has worked beautifully. domano, you could try rotating the one bar that was causing you a problem to a different site to see if another bar would work there. If none of them work at that particular spot you could use a rotary grinder to open the hole on the bar to help the bolt tread properly. And I am a big fan of the Fel-pro steel core re-useable gaskets.
Bruce

leftybass209 12-12-2014 02:25 PM

Re: Valve cover spreader bar
 
Aluminum Edelbrock valve covers also come with that rubber/metal gasket. Sealed fine on my crate 350. I was impressed by the gaskets. I do advocate the longer spreader as well, but a properly torqued stamped steel valve cover that doesn't have bends in it will seal just fine with cork and small spreaders. Problems come when leaks develop and instead of resealing, some torque the bolts tighter distorting the mating surface.

mechanicalman 12-12-2014 03:39 PM

Re: Valve cover spreader bar
 
Quote:

Originally Posted by BLT gmc (Post 6954571)
mechanicalman, I have used a flap wheel on a side arm grinder and LIGHTLY polished that entire rough surface. I must say it has worked beautifully. domano, you could try rotating the one bar that was causing you a problem to a different site to see if another bar would work there. If none of them work at that particular spot you could use a rotary grinder to open the hole on the bar to help the bolt tread properly. And I am a big fan of the Fel-pro steel core re-useable gaskets.
Bruce

Thanks for the info, trying to avoid gluing them down. :metal:

Stocker 12-12-2014 04:00 PM

Re: Valve cover spreader bar
 
Quote:

Originally Posted by domano 68 (Post 6954156)
One of the longer spreader bars prevented one of the bolts from threading well so I used the medium ones. I believe I got the leak fixed.

As long as the leak is fixed, you're good to go. But why would the longer bar keep the bolt from threading -- because the bar is thicker? If so, just use a slightly longer bolt.

BLT gmc 12-12-2014 05:58 PM

Re: Valve cover spreader bar
 
Stocker,
I have run into a similar problem. The outside radius of the hole sometimes is large enough in diameter that it will bump against the valve cover. When this happens the hole in the bar will not quite line up with the threas in the head. So you either widen the hole in the bar, or grind a bit of the outer radius of the bar where it touches the cover.

mechanicalman 12-12-2014 07:00 PM

Re: Valve cover spreader bar
 
Quote:

Originally Posted by domano 68 (Post 6954156)
One of the longer spreader bars prevented one of the bolts from threading well so I used the medium ones. I believe I got the leak fixed. I did use the Felpro rubber gasket with steel core and no RTV. My valve covers are chrome aftermarket from Chevrolet Performance Parts.

domino I prefer using studs so there is no chance of cross threading because of a little side loading, and makes gasket alignment easier.

I always use these GM ones, a little pricey though. 2 kits required, make sure they combine shipping if you buy them. Contact first they will do it but you have to ask.

#14085816

http://www.ebay.com/itm/NOS-GM-14085...6fdf22&vxp=mtr

domano 68 12-13-2014 12:29 AM

Re: Valve cover spreader bar
 
Quote:

Originally Posted by Stocker (Post 6954892)
As long as the leak is fixed, you're good to go. But why would the longer bar keep the bolt from threading -- because the bar is thicker? If so, just use a slightly longer bolt.

Yeah, I think due to the thickness of the bar and something about that back hole location.

Lattimer 12-13-2014 12:44 AM

Re: Valve cover spreader bar
 
Quote:

Originally Posted by Stocker (Post 6954892)
As long as the leak is fixed, you're good to go. But why would the longer bar keep the bolt from threading -- because the bar is thicker? If so, just use a slightly longer bolt.


Usually its a matter of manufacturing tolerances. One set of valve covers I had (cheapo Edelbrock) were a mother to get the bottom bolts in without cross threading. Between the stamping and the spreader it was off just enough so you couldn't thread it straight. I had to grind the spreader a little where it fits into the recess in the valve cover.

domano 68 12-22-2014 10:32 PM

Re: Valve cover spreader bar
 
Quote:

Originally Posted by domano 68 (Post 6954156)
One of the longer spreader bars prevented one of the bolts from threading well so I used the medium ones. I believe I got the leak fixed. I did use the Felpro rubber gasket with steel core and no RTV. My valve covers are chrome aftermarket from Chevrolet Performance Parts.

Looks like I did not get the leak 100% stopped. Its certainly better but still seeping from the back outside corners. I've gotten the bolts hand tight then put about one additional full turn to each bolt. They seem to be quite snug but nothing overly tight. Once I get the bolts in hand tight, how many turns of the wrench would equate for enough torque?

tcrist 12-22-2014 10:46 PM

Re: Valve cover spreader bar
 
Quote:

Originally Posted by domano 68 (Post 6954156)
One of the longer spreader bars prevented one of the bolts from threading well so I used the medium ones. I believe I got the leak fixed. I did use the Felpro rubber gasket with steel core and no RTV. My valve covers are chrome aftermarket from Chevrolet Performance Parts.

The chrome valve covers may be too smooth on the gasket surface area. I would rough it up a touch with a wire brush, clean both surfaces with brake cleaner on a rag and try it again.

I personally use a light touch of gasket sealer on both surfaces. The blue RTV seems to work well for me.

I normally seal the gasket onto the valve cover and let it set-up for a half hour or so before installing.

I only use cork gaskets though. That might make a difference?

domano 68 12-31-2014 12:43 AM

Re: Valve cover spreader bar
 
Found the original valve covers in a parts box that came with the truck. They are not bad but wanted to get some opinions on swapping back to these instead of the GMPP ones on their now that seem to want to leak. :)

http://i148.photobucket.com/albums/s...ps6d16bcb6.jpg

http://i148.photobucket.com/albums/s...ps8fe48b1b.jpg

http://i148.photobucket.com/albums/s...ps27d24c90.jpg

http://i148.photobucket.com/albums/s...ps4c849ab6.jpg

http://i148.photobucket.com/albums/s...ps17712bac.jpg

http://i148.photobucket.com/albums/s...ps058d747c.jpg

http://i148.photobucket.com/albums/s...psb0460393.jpg

http://i148.photobucket.com/albums/s...psd951af02.jpg

http://i148.photobucket.com/albums/s...ps96a3613a.jpg

Anyone know what this is called? Came on an end of a hose that was cut that appears to connect to the base of the air filter. It also fits in the grommet on the valve cover that has the oil cap. Its not a PCV valve. Would like to get a knew one.
http://i148.photobucket.com/albums/s...psc58e4408.jpg

http://i148.photobucket.com/albums/s...ps39e3c202.jpg

Thanks.

RichardJ 12-31-2014 01:48 AM

Re: Valve cover spreader bar
 
Not Bad? They need to be straightened out before you should ever waste your time trying to use them. A flat faced hammer and a dolly or a chunk of steel for backing is needed.

That item pictured is a spark arrester. It's there just in case of carb backfire.

Those long spreaders should be tightened until the center makes snug contact under the bolt. That will put pretty much even pressure on all three contact points.

Some of you will know, but for the others, those spreader bars are from Corvairs. The Corvair is a horizontal engine with some oil in the rocker boxes at all times, right above the gasket. Hot rodders taught Chevy to use the Corvair spreaders on SBC.

Tx Firefighter 12-31-2014 04:30 PM

Re: Valve cover spreader bar
 
If you're using the FelPro composite gaskets that are rubber with steel cores, absolutely do not put any sealer on them anywhere. They are meant to be installed dry and they work perfectly that way. Tighten them down. You'll feel it when the rubber flattens against the core.

Trust me here. I run those gaskets on every single engine in all my stuff. This set here is now on its third engine. The last engine I had them in I put ten years of near daily drivng on. When I rebuilt it, I just dropped the gaskets right back in place for another usage. Not a drop of sealant ever. Not a leak or seep or drip ever.

http://i276.photobucket.com/albums/k...psd482c7b2.jpg


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