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Using old head gaskets..

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by Traviss, Jun 26, 2008.

  1. Yes I know its not recommended ...This is why Im asking because Ive never done it before ...
    Question ..On a two stroke motor (rgv250m) if the Gasket where removed carefully and sanded smooth (on glass to keep flat.) and you coat it with a product like Permetex copper gasketing spray then fit it wait 24 hrs and tension the head ..Do you think it will work and not cause any warping or coolant tracks ..I only want it to last long enough to run it in and check for any other problems as I brought it not running...(exhaust valve hit piston have replaced both)
    Has anyone tried this method it was recommended by an vintage bike enthusiast.

  2. Valves on a two stroke?
  3. The Suzuki RGV250 has powervalves in the exhaust port to help control the powerband delivery all modern 2 strokes have them as either a reed valve or rotary valve ...So yes 2 strokes have valves sort of..
  4. Do not reuse the any of the gaskets. It might work short term, but it is bound to fail very quickly.

    I got a spare head gasket lying around for a vj22. U can have it for a tenner.

    Pv failure is no good. i presume u had the single rolled pins?, What fell into the cylinder. the middle bit?
  5. ^^
    what he said.
    pretty much dont do it.
    if it was an air cooled 2smoke, i would say."awwww, if it's your only option..." but with the RGV (i owned one) i definitely say no.
    the head gasket itself isnt exactly a bank buster anyway, from memory.
  6. It is unlikely to cause any other, permanent problems that are not repairable.

    If you are careful and run it in using the motoman method:


    then you won't need to keep it on for more than a day...

    Make sure you read the last article in the series (no 5) which explodes some myths about plain bearings. Hmmm...not many plain bearings in a 2 stroke, but it helps show how accurate the old motoman really is. ;-)


    Trevor G
  7. I got the bike off ebay ..I new it had a powervalve failure but what I found was something new ..The top and bottom valve retaining screws had come out causing the worst elongation Ive ever seen in the top cylinder the bottom had fallen free and remained undamaged but the top middle and Pin(pin never found ) had fallen in and hit the piston ..The amazing thing is there is no cylinder damage except in the PV port where the pin had rubbed But the Valves well NFG is a understatement.
  8. Thanks for the link that just made me feel a lot better about my new CBR1000 as I rode it simlar to that strait away..
  9. Would you re-use toilet paper? :roll:
    Don't be a tight ass ... chuck a newie on mate :wink:
  10. Depends on what the gasket's made of.

    If it's solid copper or aluminium, you might be able to reuse it by annealing it by heating it up with a blowtorch (to red if it's copper, as far as you dare if it's ally) and dunking it in cold water. Standard practice for many old Brit four strokes :grin: . It should soften enough to remake the seal. However, it will be thinner than a new one which might cause problems with compression ratio or squish clearance.

    If it's any other material, a new one is the only way to go.

    But yeah, in general, what the others said for a motor as highly stressed as the RGV, particularly with water cooling.
  11. Its not about being Tight mate...Its about making sure it runs before I spend to much money on it ..If its got electrical problems then I might wreak it..If its got gear box problems etc I just want to get it running for long enough to make sure every thing else is fine ,,It only takes a few minutes to strip it down and put new gaskets in but if I have to strip it down I just wasted the new Gaskets if I put them in now ....MAKE SENCE
  12. Makes perfect sense :wink:
    I guess I should have read your post more carefully :oops:
    sorry Trav
  13. Further to my previous comment on annealing ally gaskets, I've just remembered that the textbook method of ensuring you don't destroy them is to smear them with soap. Heat until the soap goes black, then quench.
  14. I've heard of powervalves on 2 smokes, but didn't even think about it when I read "exhaust valve"
  15. get the corn flake packet out weeties etc cut out three layers and paint em with varnish

    will last an hour or so before they burn out

    done it before and to get em to last use the alloy ring left over from the original gasket and adjust the height to crush em up good and tight
  16. :shock: :shock:
    be sure to get the holes for the water channels right, you dont want a hot-spot failure :?
  17. Someone must.

    The aisles in both Safeway and Coles supermarkets sport plenty of well-wrapped rolls of recycled toilet paper...

    All the best

    Trevor G
  18. Has anyone used the permetex copper gasket spray ..If I give the old gaskets a spray with this they might last long enough (1 hour or so.)any idea what its like...If the gear box and electrics are all ok Im going to put the new gasket on ,Unless anyone has an idea on how to bench test the electronics without hours and hours of work (Have done basic electronics)
    The reason Im not putting the new gaskets on is Im getting the all metel ones from tuning works in the UK and Im waiting for the new stock to fill my order.
  19. why dont u do all the other checks.
    Check the crank isnt rooted (play in the conrods).
    Check the cylinders for scoring.
    Kick the engine over for spark.
    Clean out the carbs.
    Check the oil pump.(remove clutch cover , spin the oil pump gear)
    Check the gearbox/ clutch. (2nd gear Dogs especially)

    I think u will be alright with putting the old head gaskets on. If only to get it running for under a few minutes. Just torque the head nuts to spec.
  20. I haven't but I have worked on engines after someone else has used it.

    It seems to be effective because it takes a lot of work to clean off properly!

    All the best


    PS All it will do, if it doesn't work, is leak compression out. It won't "burn" or damage anything unless you are trying to cross the Nullarbor...