Reuse a headgasket

[mattsaks]

Would you reuse a headgasket that has been torqued down and run for 20 mins on a hose, then taken off?<br />I am guessing they are a one crush only?

 

[Dhadley]

Re: Reuse a headgasket

Are you asking about motors/head gaskets in general or about a specific situation?

 

[mattsaks]

Re: Reuse a headgasket

A specific situation. It was run, then taken apart and had the head and block faces refaced then re used the gasket. Its sucking in water into all three. No probs with compression. Leaking past the gasket? Or what else should i look for?

 

[Dhadley]

Re: Reuse a headgasket

What motor? What brand gasket?<br /><br />If the gasket tore at all -- any -- when it came off then it needs replacing. We coat the head gaskets with OMC /BRP Gasket Sealing Compound. We only used OMC/BRP or Aqua Power (when they existed) head gaskets but not the F3000 AP gaskets. The F3000 gaskets will seal anything but are next to impossible to clean.<br /><br />If its getting water into all three (we assume its a 3 cylinder or one side of a V6) then we would hope that its a gasket. However since you ran it and then removed it we would almost assume that it was getting water the first time it went together.

 

[rodbolt]

Re: Reuse a headgasket

hello<br /> nope its a toss away item. the gasket has a fire ring that is a crush fit, the gasket itself has a designed crush thickness, once crushed its crushed. that being said yes I have reused them in a pinch once or twice to set a wing anchor or other temporary deal. but usually they start leaking. now is were a leak down test is mandatory. replace the gasket. and a leakage tester may help. if the cyl seals but still leaks water you have either corroded a hole through the cooling system or the exhaust divider plate.water in all thre is rare. how badly was the head warped? and was the water in the cyls the reason for the first head removal? a year and HP will help a lot.

 

[mattsaks]

Re: Reuse a headgasket

90 tohatsu. Mallory gasket set. The gasket came off fine but originally was sticky(sealant i guess). Yea it wasnt the reason for removal but when i took the head off I noticed that water had been getting into the bottom cylinder so got the head/block refaced. It was ok for a while but after it had a run i checked the plugs and they had a creamy residue on them. I have pulled the head again and it looks to have been pulling water past the gasket. Should i try it with a sealant or is it damaged/used up by being in there with a non flat head? The head was badly warped according to the machinist. I don't want to put a new gasket on there and have the same problem.

 

[mattsaks]

Re: Reuse a headgasket

I did a leakdown before i pulled the head and it was the same on all cylinders. A slight loss past the rings(i'm told this is normal) But i could hear something in the cooling system when i removed the thermostat. What sort of percentage loss is normal?

 

[TOHATSU GURU]

Re: Reuse a headgasket

Rodbolt is 100% correct. You are asking for trouble if you reuse a headgasket. A leakdown compression test is not usually all that useful. One question though...Mallory has a gasket set that fits the Tohatsu 90 ?

 

[mattsaks]

Re: Reuse a headgasket

And it looks like i've got trouble! Yea, With the price of tohatsu parts over here, we looked for an alternative and mallory did a full powerhead gasket set! I can try and look up the part number if you want. Ok, so i should double check the head for straightness and go with a new gasket?

 

[TOHATSU GURU]

Re: Reuse a headgasket

Yes. get a sheet of some fine sandpaper and lay it on a piece of flat glass. Run the head across it it in a figure 8 design until it does not have any high spots. Slap the gasket it on and torque it down. After 5 hours, re-torque the head again.

 

[mattsaks]

Re: Reuse a headgasket

New gasket bought, fitted and test driven this afternoon. Nice clean/oily plugs. Increased flow out telltale. Lesson learnt! Thanks all.