Cylinder Compression of my engine v jap import engine

Engines, Transmissions & Final Drive questions and answers

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marty085
Racing Driver
Posts: 706
Joined: Wed Jun 22, 2011 10:08 pm
Vehicle: NA8
Location: Blakehurst NSW

Cylinder Compression of my engine v jap import engine

Postby marty085 » Tue Nov 08, 2011 1:05 pm

Heya,

1st question: My current engine has compression test results between 189-195 for all 4 cylinders. Cylinder 3 however was slow to reach this, first couple of strokes were half the corresponding results for the other cylinders. I've read that this can be a sign of worn piston rings... However my engine stops smoking after a while.. so that doesnt really add up.. thoughts?

2nd question: i was looking at an import engine and the place reckon they tested it and found it 210psi for all 4 cylinders.. that seems very high.. could that be sign of an older engine? carbon buildup and what not?

Maybe I should stick with mine and get it looked at for maybe new rings and a head overhaul to fix possible leaking stem seals.

-Marty

93_Clubman
Speed Racer
Posts: 11856
Joined: Mon Aug 08, 2005 11:35 pm
Vehicle: Clubman
Location: Melbourne

Re: Cylinder Compression of my engine v jap import engine

Postby 93_Clubman » Tue Nov 08, 2011 2:48 pm

189-195 is ok, but number 3 being slow is a problem. Good explanation of why smoking reduces by kosby in this: viewtopic.php?f=29&t=48652

According to xmx106 some report getting 215PSI in this:
viewtopic.php?f=29&t=46853

Need to weigh up the cost of getting yours fixed versus getting the import engine - how much do they want for the imported engine?

marty085
Racing Driver
Posts: 706
Joined: Wed Jun 22, 2011 10:08 pm
Vehicle: NA8
Location: Blakehurst NSW

Re: Cylinder Compression of my engine v jap import engine

Postby marty085 » Tue Nov 08, 2011 5:15 pm

Thanks mate.

$1250... plus $100 or so shipping.

the idea was that this place has been doing it for 15+yrs and therefore they know a good engine when they see it (plus 6mth warranty).. but the 210 psi threw me a little tbh, when supposedly mazda reckons its 185 max.

93_Clubman
Speed Racer
Posts: 11856
Joined: Mon Aug 08, 2005 11:35 pm
Vehicle: Clubman
Location: Melbourne

Re: Cylinder Compression of my engine v jap import engine

Postby 93_Clubman » Wed Nov 09, 2011 1:55 pm

So $1250 + shipping + removal of old eng & fitting of replacement (unless you DIY) = $2k+ versus what ever your old eng requirements are. If rebuild, then replacement eng is cheaper, but if yours doesn't need much work, & you can get a written quote for it & DIY what you can, then may be fix yours up. GL!


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