Norminal Compression pressure of a 86mm bore 3TC?

[CHB]

i'm thinkiing of performing a compression pressure test on my 3TC cause at this moment i still fail to get it started..
what is the normal compression pressure of a 86mm X 78mm 3TC?

[sillycar chick]

Ive seen a few different figures in different manuals, but you should expect to see somewhere around 185psi. Anything below 165psi I would think to be getting a bit too low, although I think the manual states about 145psi is the absolute limit. And if its anywhere higher than 195psi then you either have serious problems or someone has been playing with the engine previously. Why dont you do a test and post up what you get?

PS: keep in mind you dont want any variation between cylinder readings either. Anything over 15psi difference may be worth checking out.

[CHB]

i don have any compression test tools but i'm trying to make myself one. looking for brass nipple but can't find any threat size of 1.5 was what we have on the spark plug.
i'm planning to drill a thru hole on a spark plug, then connect a pressure guage on.
will it work?

[jezza323]

for the $25 that it costs to buy a comp tester from super cheap, buy one

[CHB]

it cost RM180, which is equivalent of AUS$70 here in Malaysia