Metal gasket for 5.0L timing cover?

[1998Exp]

Just like happened to many others, my 5.0L started leaking coolant from the top corners of the timing cover at around 140K. About 10K after the repair the leak returned. This week I finally decided that enough is enough and tore everything down for a second time. Found that the narrow section of the paper gasket next to the coolant passage on the passenger side was broken. My theory is that the bolts lost some torque and this allowed the hot pressurized coolant to seep under the gasket and damage it.
A few days ago I discovered that one of the engine builders (Street Strip Racing) sells a steel gasket, which I purchased. I now see that it's not a real gasket, but simply a 20-mil thick piece of sheet metal, stamped just like the paper one. They advise to apply a thin layer of RTV to both sides and 'promise' that it will never fail. For sure, that steel won't fail, but will it seal? Unlike a real gasket there is nothing to compress, except for the applied RTV. And what prevents that RTV from being squeezed out when torquing the bolts? In fact, I can't see any difference between using this 'gasket' and simply applying RTV between the block and the timing cover and nothing else. I am now scratching my head, trying to decide whether to use this thing or gamble on the paper gasket again. Any opinion will be appreciated.

 

[Runnin'OnEmpty]

I had the same thoughts when installing a stainless
steel valve cover gasket recently. It had a minimal
rubber seal but was mostly metal. I installed using
Permatex Aviation Gasket Sealer, and it hasn't leaked
a drop since.

I would use the metal gasket, since it would conform
to minor defects on both sealing surfaces, using your
favorite gasket sealer. I think this system is much better
than paper gaskets.

 

[Turdle]

The timing cover might be warped. Lay it on a good level ( granite countertop) surface to check. Any amount of warp means it needs replacing.

 

[masospaghetti]

Normally metal gaskets are made from a soft, pliable metal that will conform to minor defects in the mating surface. Head gaskets in particular are normally metal.

The RTV is meant to seal scratches, pits, etc that the metal cannot fill. Is a metal gasket better than just using RTV alone? Probably.

And what prevents that RTV from being squeezed out when torquing the bolts?

If you had two perfectly machined surfaces then yeah, the RTV would squeeze out. But the point of the gasket is that the surfaces aren't perfect. The RTV is there to fill imperfections. It's no different with a metal gasket.

 

[1998Exp]

Thank you Turdle - and thanks to all who provided advice.
Put the timing cover on the flattest surface I could find around here. Found that the thickest feeler gauge that I can stick anywhere is 5 mils - and that's in one bottom corner only. The rest is 2-3 mils. Does this qualify for warped?

The timing cover might be warped. Lay it on a good level ( granite countertop) surface to check. Any amount of warp means it needs replacing.

 

[Turdle]

I think a gasket and RTV would seal that. Does the 5 mil gap line up with the split gasket?

 

[1998Exp]

No, the split is at the top corner coolant passage, but the 5 mil gap is at the bottom corner just above the oil pan.

I think a gasket and RTV would seal that. Does the 5 mil gap line up with the split gasket?

 

[97MarkVIII]

What brand gasket did you use?. I never had issues with Fel-Pro gaskets except cork valve cover gaskets but those are junk anyways.

Coat the gasket with something like Permatex High Tack.Plus it will hold it in place and it also comes in a spray can.Also if you can replace the timing cover bolts.

 

[1998Exp]

Thanks for your advice, 97MarkVIII. The paper gasket that did not last long was Fel-Pro, but I don't necessarily blame them. As mentioned, I found out that the bolts lost much of their initial torque, perhaps because they had some oil on them; and this might have opened a gap for the hot pressurized coolant to damage the paper. I will make sure to clean the threads and use some Locktite this time.
When doing this job the first time, I did replace those that were rusted, and now they all still look good. Incidentally, replacing these bolts is a hassle, because none of them is standard length.

What brand gasket did you use?. I never had issues with Fel-Pro gaskets except cork valve cover gaskets but those are junk anyways.

Coat the gasket with something like Permatex High Tack.Plus it will hold it in place and it also comes in a spray can.Also if you can replace the timing cover bolts.

 

[azstang]

Bringing this thread forward as I’m about to perform the timing cover gasket replacement for the third time on my 00 Ex with 176K. I also had to perform the same repair on a 5.0 F150 years ago. Figured I can’t be the only only one with his same issue and it looks like I’m not.

1998Exp, wondering how the steel gasket is working and how many miles you have on the repair? Do you have a link to the gasket as well?

Thanks,
Shawn

 

[1998Exp]

Bringing this thread forward as I’m about to perform the timing cover gasket replacement for the third time on my 00 Ex with 176K. I also had to perform the same repair on a 5.0 F150 years ago. Figured I can’t be the only only one with his same issue and it looks like I’m not.

1998Exp, wondering how the steel gasket is working and how many miles you have on the repair? Do you have a link to the gasket as well?

Thanks,
Shawn

It's holding very well; no leak at all in 2-1/2 years. Don't know if you can take that to the bank because I only drove the Ex 12,000 miles since the repair. And sorry, no link to the source. Tried looking for "Street Strip Racing," the business from which I bought it back then, but nothing like that comes up.

 

[azstang]

Thanks. You’re right though in that 12,000 miles isn’t really a glowing endorsement of success yet!

 

[azstang]

Found a better gasket from Cometic. It has a steel core with a rubber surround.

https://www.summitracing.com/parts/CGT-C5660-020

I called Cometic and they recommend installing it dry without any RTV. Not sure if that’s the best way with this stubborn leak though.

 

[CDW6212R]

That's interesting that there are metal timing cover gaskets. Any kind can work and not leak, what really matters is how clean the surfaces are, if the bolts ever loosen, and if any sealant is used.

I've never had one I installed leak, and that's been about ten, all on SBF's. The normal gaskets are all I've ever used, but I have always used either High Tack spray sealant, or Ultra black/grey RTV. The spray on High Tack works very well, it's the easiest by far to use. You simply spray both sides of the gasket, let it set up for a minute or so, and assemble the parts. RTV is the most common people use, and the Ultra RTV is very strong in all applications.

Timing covers don't usually leak from what I've seen, old age and loose bolts can create leaks for sure. Use anti-seize on the bolts, and go very slowly sealing the bottom edge, especially the oil pan surface and seams(where the pan is often dropped to get the cover off). That oil pan area is very common to leak, watch that way more than the timing cover.

 

[roscoe 0202]

if that picture is the gasket you're buying you better have a chev.
roscoe

 

[CDW6212R]

That was a "stock picture", a vague representation, yes a Chevy too.

 

[azstang]

I have always used either High Tack spray sealant, or Ultra black/grey RT.

The first time I replaced this gasket the new one went on with High Tack. The gasket that’s on there now has Ultra Black RTV.

I’m pretty sure that the bolts are either loosening or stretching as they are very long. I’ve installed them with antisieze compound both times to aid in easy removal. I’ll try the Loctite this time.

if that picture is the gasket you're buying you better have a chev.
roscoe

Yeah, I hope that picture is wrong!

 

[CDW6212R]

The bolts can be made pretty tight when they are good and strong, older bolts that show corrosion(not just dirty) you have to be careful tightening those. I've reused a few ugly looking OEM bolts, but you don't want to. I do wish they were easier to buy from Ford, most of them are obsolete when you want them.

 

[azstang]

The Cometic gasket arrived and it looks like it will fit. Leaning towards installing it dry like the manufacturer recommended and using Loctite on the bolts.

The blue gasket is a paper FelPro.

 

[CDW6212R]

I do like the color of that, I might have to try one just to do away with the look of the regular gasket sticking out.