decompresion bolt

7 replies to this topic
  • mat

Posted July 23, 2002 - 07:03 PM


has any one had trouble after taking out the decompresion systme bolt, the one that goes into the side of the engine by the #4 exhaust vavle, if u tighten mine just so that the washer seats, the decompresion lever wont bugde, but if u keep thew bolt loose, it works fine but oil gets out, should i just try new hardware?

  • gal

Posted July 23, 2002 - 08:38 PM


hi mat
i had the same prob. when i did m valves
just get a helicoil set, sorry but dont remember the size, i think its 6mm*1mm.
do a search on DECOMPRESOIN and u will find it...
good luck

  • freestyle111

Posted July 23, 2002 - 10:25 PM


use a thicker washer so end of bolt doesnt hit decompression shaft.if your threads arent stripped you dont need to helicoil.

  • skthom2320

Posted July 24, 2002 - 04:02 AM


Are your sure you had the decompression shaft fully inserted? There is a groove in the shaft that the end of your bolt needs to fit into. When I replaced my decomp shaft the first time I didn't get it fully inserted and experienced the same thing you are.

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  • mat

Posted July 24, 2002 - 04:34 AM


thanks for the replys guys, skthom2320, when u say groove, do u mean the one towards the end of the shaft, which would be a female end on the shaft and the male conector on the bolt, or the groove that is raised on the decompresion shaft, i see 2 possible grooves, sorry if that confused u

  • freestyle111

Posted July 24, 2002 - 05:45 AM


there is a v-groove in the center of shaft that has to be lined up with bolt hole.thats why bolt is tapered it fits in groove and keeps shaft from sliding out.if decompression lever is still hard to pull after you have bolt aligned with grooved and tightened up,its probably because copper washer has been compressed or been worn down and its letting bolt thread in to far.your supposed to use new copper washers whenever you remove either get new washer [you can also add another very thin washer behind it]or file about 1\16 end of bolt.

  • skthom2320

Posted July 24, 2002 - 12:12 PM


freestyle answered the question nicely...

Let us know how it works out.

  • meangreen75

Posted July 26, 2002 - 05:22 PM


I'm having the exact same problem right now. I over tightened that bolt and had to helicoil it. Now it's leaking oil big time too. I'm going to get the new washer and I've been instructed to use red loc tight as well. Hopefully that'll heal the blue beast.

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