If you reuse MLS head gaskets...

[BradH]

... do you need to disassemble them and clean each layer separately?

In this case, they would be the Mr. Gasket MLS run on my engine for just the dyno session. However, they did have some coolant leakage, which is why I'd coat them w/ the Mopar-brand sealant used when ChryCo was doing all the warranty conversions from blown composition gaskets to MLS during the late '90s.

I don't think they would have collected enough "grunge" between the layers in that short amount of run time to require disassembly. My a$$umption is they'd be OK to wipe clean on the head & block surfaces before applying the sealant lightly on both sides. However, if someone wants to provide advice or guidance different from what I'm proposing, please let me know.

I remember from a previous thread somewhere there were (are) people unhappy w/ Mr. Gasket MLS gaskets after they shifted from repackaging Cometics to whatever their (probably offshore) source is now. If, even re-coated, the Mr. G MLS stuff is suspect, I'll switch to Cometics and still use the same sealant out of concern for fluid leaks. I suspect the source of the fluid leaks could be that my block decks aren't "textbook smooth" enough for MLS installed dry as I did before. The heads, however, are fine.

Thanks - Brad

[CGT]

I haven't had any issue not taking them apart. I just use brake cleaner to clean them all up and recoat the outer layers with the red Mopar spray sealant. I've seen people take them apart and spray each layer, and also just pull apart and try to mist in between the layers. Each way always seems to work out fine.

[peejay]

I've only ever used any "new" sealant like Copperkote if the old sealant stuck to the deck when removing the gasket. If it came off clean, it can go right back on again.

Because of this, there should be no reason to have to clean and reseal each individual layer. As long as it stayed riveted together, it's going to be fine. The internal layers' sealant doesn't seem to come off and stick on the smooth metal vs. the way it does on a relatively rough machined surface.

[swampbuggy]

Is reusing MLS head gaskets common practice that has "NO" chance of regret or is their a percentage of, i should have just bought new ones ? Mark H.

[peejay]

Is reusing MLS head gaskets common practice that has "NO" chance of regret or is their a percentage of, i should have just bought new ones ? Mark H.

If you have to pull the heads off before the engine even fires because you find out the dipsh* who cut the valves used the wrong collet and the valve seats are octagonal, you're going to want to reuse the gaskets and they will probably not even need to be cleaned/recoated.

If the engine shortened a rod on the dyno and you need to pull one of the heads to replace it, you might need to recoat it because it had been heat cycled and some of the sealing coat will stick to the decks.

I've never regretted reusing an MLS gasket, I've only regretted using them at all in certain applications (Buick V6 with 8 head bolt holes, they always leak oil through the gasket)