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Model specific boards => Golf mk2 => Topic started by: wilson on 16 May 2009, 18:02

Title: compression results
Post by: wilson on 16 May 2009, 18:02

results on my 1990 16v were

1=12 bar
2=11.5
3=11.2
4=11.9

anybody with experience think that is low at all ?

Just trying to eliminate that the rings are causing smoking before i put it in the garage !

Oh I also noticed that 2 of the sparkplugs were very loose !!!  oops !

Thanks
Wilson

Title: Re: compression results
Post by: neils on 16 May 2009, 18:09

not sure on what the presure should be but there pritty even which ia a good sign.

dose your car smoke all the time or just when cold?
if it's just cold then i would say it's more likely to be your valve seals

Title: Re: compression results
Post by: wilson on 16 May 2009, 18:11

Well its mainly on start up warm or cold, but i do notice there is sometime a bit of a cloud when I really floor it...   and can smoke a little on tickover...   Engine is very smooth and pulls very very well for standard !

Thanks

Title: Re: compression results
Post by: danny_p on 16 May 2009, 18:17

CR is well withing limutes and looking heathy

Title: Re: compression results
Post by: wilson on 16 May 2009, 19:22

Quote from: danny_p on 16 May 2009, 18:17

CR is well withing limutes and looking heathy

Thanks danny,   although not 100% would that help me assume its more than likely the valve seals ?

Title: Re: compression results
Post by: Ben Lessani on 16 May 2009, 19:27

Checking the valve seals should be easy? Just park the car, then try and start it the next day - if its smokey as hell, then its the stem seals.

Plus, the steam seals won't really affect compression - that's down to the valve head and guides themself.

Put about a teaspoon of oil into each cyl, then repeat the compression test - it should let you know if its the rings.

Title: Re: compression results
Post by: wilson on 16 May 2009, 19:34

Yeah, it is mainly on start up, it puffs out quite a bit.

what sort of difference should i expect from the results with oil in the cylinder ?

Thanks for comments

Title: Re: compression results
Post by: Ben Lessani on 16 May 2009, 19:37

Depends on the wear on the rings doesn't it?

If there's no noticeable difference, then either you haven't dropped enough oil in or the rings are fine.

0.5 - 1.5 psi difference is likely on worn rings.

Title: Re: compression results
Post by: danny_p on 16 May 2009, 20:53

tho  the cr will allways go up  a bit on a wet test.   

kr bottom end is over engineered they are seriously tough.   valve stem seals go hard with age espectaly if its been parked up very common  problem the other thing worth checking is that the valve guides are good sometimes the guides wear causeing the seals to fail this can also lead to valve not seating as well as it chould and slight loss of compression