Which RTV Sealant to use??
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What fluid are you sealing in there? Hylomar is good for coolant but doesn't resist oil very well
I have a 98 740iL that has oil that leaked thru the valve covers and was in the Coil On Plugs and outside the on engine block. This to my understanding is a problem because it forces mis- fire codes (it did in mine). The replacement gaskets is made of rubber and it will see plenty of oil in the range of 500 degrees or so.
Went to Permatex website but another guy had recommended that I use Advance Hylomar Sealeant instead.
Went to Permatex website but another guy had recommended that I use Advance Hylomar Sealeant instead.
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Is grey Permatex the grey substance that's surrounding my differential drain and fill plugs?
They make a high-temp RTV, the orange stuff. When you are buying the goop,check out the label on Permatex Aviation Forma-Gasket. I use it for sticking on oil pans, Timing covers, seals, etc. It is old school , but still very useful.
Originally Posted By: Sierra048
Is grey Permatex the grey substance that's surrounding my differential drain and fill plugs?
I doubt it since the grey Permatex is a gasket maker and the fill and drain plugs on a differential are pipe threaded and require a thread sealant.
Is grey Permatex the grey substance that's surrounding my differential drain and fill plugs?
I doubt it since the grey Permatex is a gasket maker and the fill and drain plugs on a differential are pipe threaded and require a thread sealant.
not following you but assuming that what you are talking about is the valve cover gasket, they are made of fuel/oil resistant man-made rubber called nitrile.
And unless there's specific call for RTV on uneven mating surface on the block, otherwise, never use RTV on nitrile valve cover gasket as a 1/2 arsh patch job.
If your leak to the spark plug tube hole is due to hardened V/C gasket over years of usage, then by all means, clean the holes, wipe down the V/C gasket mating surface and then install a set of fresh new V/C gasket set.
Anyone who recommends RTV on top of V/C gasket other than uneven block to cover mating surface (factory would have specified that), I'd stay away from that mech.
Q.
And unless there's specific call for RTV on uneven mating surface on the block, otherwise, never use RTV on nitrile valve cover gasket as a 1/2 arsh patch job.
If your leak to the spark plug tube hole is due to hardened V/C gasket over years of usage, then by all means, clean the holes, wipe down the V/C gasket mating surface and then install a set of fresh new V/C gasket set.
Anyone who recommends RTV on top of V/C gasket other than uneven block to cover mating surface (factory would have specified that), I'd stay away from that mech.
Q.
Some engines do call for a little RTV to fill in the gaps the gasket may not conform to - Honda and Toyota call for a little bit on the ends of the the half-moon plugs and on the corners where the gasket has a sharp bend.
Toyota black FIPG is better
Originally Posted By: Quest
not following you but assuming that what you are talking about is the valve cover gasket, they are made of fuel/oil resistant man-made rubber called nitrile.
And unless there's specific call for RTV on uneven mating surface on the block, otherwise, never use RTV on nitrile valve cover gasket as a 1/2 arsh patch job.
If your leak to the spark plug tube hole is due to hardened V/C gasket over years of usage, then by all means, clean the holes, wipe down the V/C gasket mating surface and then install a set of fresh new V/C gasket set.
Anyone who recommends RTV on top of V/C gasket other than uneven block to cover mating surface (factory would have specified that), I'd stay away from that mech.
Q.
Yes, the gasket rep I talked to said for valve cover gaskets, you can use adhesive to attach them to the valve cover (I was using a cork gasket at the time on a 1974 Chevy C-10 inline six) but to just clean the head where it contacts the gasket. Of course, there are applications where you're required to use RTV on the corners along with the gasket. Sealing the small block Chevy intake manifold comes to mind.
not following you but assuming that what you are talking about is the valve cover gasket, they are made of fuel/oil resistant man-made rubber called nitrile.
And unless there's specific call for RTV on uneven mating surface on the block, otherwise, never use RTV on nitrile valve cover gasket as a 1/2 arsh patch job.
If your leak to the spark plug tube hole is due to hardened V/C gasket over years of usage, then by all means, clean the holes, wipe down the V/C gasket mating surface and then install a set of fresh new V/C gasket set.
Anyone who recommends RTV on top of V/C gasket other than uneven block to cover mating surface (factory would have specified that), I'd stay away from that mech.
Q.
Yes, the gasket rep I talked to said for valve cover gaskets, you can use adhesive to attach them to the valve cover (I was using a cork gasket at the time on a 1974 Chevy C-10 inline six) but to just clean the head where it contacts the gasket. Of course, there are applications where you're required to use RTV on the corners along with the gasket. Sealing the small block Chevy intake manifold comes to mind.
For the typical valve cover gasket, no additional sealant is needed. The only time I would recommend additional sealant (RTV) when using a molded rubber gasket, is when it crosses a seam of some kind- like when a valve cover gasket has to seal to the cylinder head and timing cover. Where the timing cover and head meet, smear a small dab there (approx 1/4"-3/8" wide and .030" thick) Another place is where a valve cover gasket goes over a cam bearing cap. Right down in that little corner, put a pea sized blob.
Now before everyone attacks me and waves their gasket manufacturer instructions in my face (yes, I've read them and I know what they say), realize that OEMs do this very thing from the factory. I've also seen what happens when you don't. A guy I used to work with was doing cam phasers on a 5.4 Ford. It's a bugger just to get the valve cover off- he had to evac the A/C. Anyway, he put on new valve cover gaskets during the reassembly and finished up. Well the customer came back, complaining of an oil leak. Close inspection showed the drip originated at the top of the cylinder head to timing cover seam. He had used no RTV there and it leaked. This time around, he used a small dab right there and no leaks.
Now before everyone attacks me and waves their gasket manufacturer instructions in my face (yes, I've read them and I know what they say), realize that OEMs do this very thing from the factory. I've also seen what happens when you don't. A guy I used to work with was doing cam phasers on a 5.4 Ford. It's a bugger just to get the valve cover off- he had to evac the A/C. Anyway, he put on new valve cover gaskets during the reassembly and finished up. Well the customer came back, complaining of an oil leak. Close inspection showed the drip originated at the top of the cylinder head to timing cover seam. He had used no RTV there and it leaked. This time around, he used a small dab right there and no leaks.
Originally Posted By: Olas
What fluid are you sealing in there? Hylomar is good for coolant but doesn't resist oil very well
+1 Its great on plastic hose connectors that like to weep even when the hose clamp is tight. Not so great with oil,
What fluid are you sealing in there? Hylomar is good for coolant but doesn't resist oil very well
+1 Its great on plastic hose connectors that like to weep even when the hose clamp is tight. Not so great with oil,
I also use the Permatex Copper RTV. Overkill on diffs and valve covers but never a leak and never a problem. The basic black stuff never lasted more than a few years on my LT1 intake where I finally used the Copper and it's been leakfree for going on 8 years.
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