Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: JueV6 on 09 July 2008, 16:00:33

Title: Compression Test....
Post by: JueV6 on 09 July 2008, 16:00:33

Can anyone tell me please if there is an easy way to do a compression test on a V6. Cylinder 1, 3, 5 are easy to get to, Is there an easy way to do 2, 4, 6 :question

Title: Re: Compression Test....
Post by: JueV6 on 09 July 2008, 17:03:11

Take that as a no then.   ;D ;D ;D

Ok the results are

5: 200 psi                        6: 230 psi
3: 190 psi                        4: 230 psi
1: 210 psi                        2: 230 psi

no mayo in the header tank no mayo in the sump. all plugs are normal

any ideas, anyone :question

Title: Re: Compression Test....
Post by: CBH on 09 July 2008, 17:30:57

You should do a compression test twice.
do it once and record the reading
than put a teaspoon of oil down the plug hole and do it again,
if you get a much better reading on the 2nd check then you have a problem with the piston rings/ bore ware.
If it does not improve then the there's a problem with the valves/ heads
the 190 reading looks low to me.

Title: Re: Compression Test....
Post by: Dazzler on 09 July 2008, 17:52:15

You should also do the test with Wide Open Throttle WAT

Title: Re: Compression Test....
Post by: Kevin Wood on 10 July 2008, 00:04:08

Might be worth checking the cam timing as one bank is better than the other. Readings are in the right ball park though.

Kevin

Title: Re: Compression Test....
Post by: JueV6 on 10 July 2008, 02:52:36

was thinking about whipping the head off but i have the dubious job then of cam belts....NOT good

Title: Re: Compression Test....
Post by: Kevin Wood on 10 July 2008, 09:49:18

What are the symptoms you are seeing? Because those compression figures don't suggest anything catastrophic has happened...

Kevin

Title: Re: Compression Test....
Post by: JueV6 on 10 July 2008, 10:12:03

started with miss-fire on cold start, with a very slight uneven idle when warm even on LPG (so unlikely to be fuel), Tuesday the EML came on and when i did the paperclip test the result was 16 (knock sensor), Did the comp test yesterday with the above results  :-/

Title: Re: Compression Test....
Post by: Kevin Wood on 10 July 2008, 11:00:08

My first step would be to check the ignition system and the wiring to that knock sensor. Certainly a lot of things to rule out before taking the heads off.

Kevin

Title: Re: Compression Test....
Post by: JueV6 on 10 July 2008, 11:37:14

Just been to check wiring and connectors kevin, bank 1 knock sensor wire had chaffed and was earthing out near the front pulley's / air con pipe.

After checking all the compressions, it started this morning NO miss fire but still EML moved chaffed wire and EML went out, Just going to road test it now.

Will let you know how it goes.

thanks for the advice :y :y

Julain