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? a posé la question dans Cars & TransportationMaintenance & Repairs · il y a 3 ans

Is it necessary to apply Assembly lube after this? Nissan altima QR25DE 150k miles?

My engine has been sitting with the cylinder heads off for 6 months, all the oil was drained so it was sitting without oil.

Im going to put back the heads...camshafts etc. Should I use regular 10w30 oil to lubricate while Assembling it back together? A mechanic told me "no problem, just smear oil with you fingerboard on moving partes,, you dont need assembly lube"....Yet Im suspicious.

That same mechanic told me to apply grease (red one for ball bearings) on the head gasket (new factory gasket) on both sides, just smear it with my fingers.

He told me that a guy (teacher of His) who worked with japanese Toyota factory japanese guys taught him that technique. He said it allows the gasket to be removed and reused f they want to pull the heads off due to some "failure".

Is that ok?

6 réponses

Pertinence
  • il y a 3 ans

    Lube parts with motor oil as you put them together. Assembly lube is for assembling all new parts together that have never been lubricated. If you put the head gasket on right the first time, you don't need to prepare it for repeated removals.

  • Anonyme
    il y a 3 ans

    When you get the head(s) back on the engine, hand crank it with no spark plugs until you see oil on the head valve train to pre lube the engine. I'm cheap and you are not completely assembling a dry engine, I put a dab of 90W gear box lube on the OHC cam bearings during cam installation, only enough to keep it spinning free until you can crank the engine and get oil pressure. Then final torque the cam journals and install the head cover(s) and spark plugs. The layered head gaskets go on dry, use acetone to clean the mating surfaces and use NOTHING on the cleaned head gasket surfaces! Always use new TTY bolts and new head gasket(s). This process is something you DON'T want to mess up and have to do over again! I find the best prices on new head gasket sets with TTY bolts at carparts (dot com).

    BTW, Orileys sells a 1/2" drive TTY bolt angle gauge for $12 bucks, you'll need one to properly do 2 or 3 round angle to yield bolts.

  • JetDoc
    Lv 7
    il y a 3 ans

    NEVER re-use a head gasket after it has been torqued down. The gasket won't fully recover to new specs, and it may fail if it is re-used. If you're going to apply grease to ANY gasket, just use it as a THIN film of lubrication and NOT in big globs.

  • Anonyme
    il y a 3 ans

    Diesel fuel is ideal to lubricate dry components. Squirt it all over pistons bearings etc. Rotate the engine by hand with the spark plugs disconnected to distribute the diesel oil. Use fully synthetic 5w-40 when you fill up with oil. Walmart sell it at sensible prices.

  • Kenny
    Lv 7
    il y a 3 ans

    You would put assembly lube if the parts(bearing, camshaft, etc..) are new. It does not hurt to do it however.

    Never heard of the grease to the head gasket. I would not do that. I never reuse a head gasket because you have already torqued it down.

    Edit: also the grease will also make the torque reading incorrect.

  • Anonyme
    il y a 3 ans

    why not ?? it would be cheap insurance ..........................

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