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Compression testing
matt.c - 10/1/10 at 08:24 PM

Im thinking of buying a compression tester to check my engine. How do you use one?

How do i find out how much compression i should have?


pewe - 10/1/10 at 08:30 PM

IIRC testing on a two-stroke is different to that on a four stroke so might be worth checking that aspect before buying/hiring the kit. Normally the kit will come with full instructions.
Cheers, Pewe


Stuart_B - 10/1/10 at 08:31 PM

hi matt, to do a compression test is simply, just get your compression tester, take all the plugs out, and put the tester in one of the plug holes and hold the throttle wide open, and crank a few spins, and read the reading on the gauge.

check all cylinders, to see if they are the same.

if this is your 2 stroke kart engine i would reckon 130psi. do not qoute me on that figure through.

hth

stuart


franky - 10/1/10 at 08:45 PM

have you checked for a holed piston yet?


matt.c - 10/1/10 at 08:46 PM

quote:
Originally posted by franky
have you checked for a holed piston yet?


I think it looks ok. But i know sh*te.


franky - 10/1/10 at 08:47 PM

have you asked on www.karting.co.uk


matt.c - 10/1/10 at 08:58 PM

quote:
Originally posted by franky
have you asked on www.karting.co.uk


Yep. Got a friend coming to have a look on wednesday but i think it could be bad.


ReMan - 10/1/10 at 09:44 PM

I presume this is a single cylinder engine?
In which case the comression tester may be a waste of time as the more useful measure is for compariason across cylinders rather than an outright score.
It may be rough and ready but you should be able to tell if there is enough compression to start it by sticking your finger on the plughole!or just the feel of turnig it over to start it.
As mentioned by another, if its been stood they can be a pig to get them going, but hotting up the plugs and easystart should help


will121 - 11/1/10 at 12:43 PM

ive got a compression tester if you wis to borrow on from either Norwich/Dereham, is it problem with kart engine? if its holed piston as said would think you would be able to feel little or no compression or might be able to see with torch through plug hole as hole is generally direct below spark plug. is it problem with just not starting?