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a few months back i had a compression test done, the weakest cylinder read 70psi, my question is, is this now a tired engine? Strictlty only good for stock boost? Car smokes when idling only after a few seconds now, not all the time but can be embarresing at traffic light, btw i replaced my pcv valves already...

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70psi is pretty low and will point to worn bores or valves - the test method does indicate which it's likely to be. However, in either case I would expect it to burn a little oil and a little oil does make a lot of smoke !

Yes - its a tired engine.

 

Probably not a good idea to run increased boost if you need it as regular transport. Best start making a plan of action bud..

well to give you some idea,

 

Nissan service manaul

 

186psi is normal (just came out of the factory) and is good

145psi is minimum (they advice checking the valve seats and piston rings)

 

with no more than 14psi diffference between cylinders.

 

id start planning for either an engine rebuild, or replacement.

Edited by vodkashots

  • Author

ok, thanks guys, car isnt my everyday, only my toy does about 4k miles a year, we talking rings and pistons or entire rebuild? Ball park figures guys?

well to give you some idea,

 

Nissan service manaul

 

185psi is normal (just came out of the factory) and is good

145psi is minimum (they advice checking the valve seats and piston rings)

100psi is shonky and could detonate at any minute

60psi... are you nuts, stop driving the damn thing!

with no more than 14psi diffference between cylinders.

 

id start planning for either an engine rebuild, or replacement.

 

More like it.. :biggrin:

jimmer does a full engine rebuild for around the 2k mark if you take just the engine, 3k if he has to remove it.

 

But you will get a full forged bottom end with cosmetic head gaskets as well, so well worth it, plus the knowledge that you basically have a fresh engine in your zed.

 

its also a lot better than just having part of the work done and running into more problems later.

I could do with doing a compression test on mine tbh, just to see how it does

More like it.. :biggrin:

 

thats the revised addition, nissan released the layman version not long after june 94

 

it contains many help full things for the less technially minded, like

 

The PTU is the thing stuck on to the plastic front part of the engine, its got 2 cables going to it to help you find it, its also wedged inbetween the two hot pipes (if the engine has been running) cold pipes if the engine hasnt, getting too it is going to be a bit of a bugger if you havent removed the pipes going to the big rib cage looking thing on top of the engine.

 

You will need arms like an octopus to get to everything you need, have fun changing it.

jimmer does a full engine rebuild for around the 2k mark if you take just the engine, 3k if he has to remove it.

 

But you will get a full forged bottom end with cosmetic head gaskets as well, so well worth it, plus the knowledge that you basically have a fresh engine in your zed.

 

its also a lot better than just having part of the work done and running into more problems later.

 

Eh?

 

Reckon on about 3.5k for engine-out rebuild or about 1.8k for a drive in - drive out engine swap.

 

Get a proper diagnosis first though, but from the sounds of it, it will need stripping down.

Eh?

 

Reckon on about 3.5k for engine-out rebuild or about 1.8k for a drive in - drive out engine swap.

 

Get a proper diagnosis first though, but from the sounds of it, it will need stripping down.

 

im sure jimmer will correct me, im not the one who charges after all, but last time i spoke to jimmer, he said he always puts eagle rods and wisco pistons in on a rebuild.

 

ok you will still have the Stock crank but thats not a bad thing in its self.

 

may be i should of said, around the 3k mark lol

jimmer does a full engine rebuild for around the 2k mark if you take just the engine, 3k if he has to remove it.

 

But you will get a full forged bottom end with cosmetic head gaskets as well, so well worth it, plus the knowledge that you basically have a fresh engine in your zed.

 

its also a lot better than just having part of the work done and running into more problems later.

 

Changed your cosmetic spelling mistake :gunsmilie:

Edited by vodkashots

im sure jimmer will correct me, im not the one who charges after all, but last time i spoke to jimmer, he said he always puts eagle rods and wisco pistons in on a rebuild.

 

ok you will still have the Stock crank but thats not a bad thing in its self.

 

may be i should of said, around the 3k mark lol

 

I thought the whole bottom end was forged as standard?

 

You can have Eagle rods if you wish, but probably aren't necessary and aren't included in the rebuild cost.

 

The Wiseco pistons and Cometic head gaskets are.

 

Cheers

:blink: eh?

 

lol it was a pun, because it was both a cosmetic mistake (i.e. spelling) and you spelt cometic head gasket - cosmetic head gasket, which I reckon if it existed would be pretty flimsy and not up to much :boat:

I thought the whole bottom end was forged as standard?

 

You can have Eagle rods if you wish, but probably aren't necessary and aren't included in the rebuild cost.

 

The Wiseco pistons and Cometic head gaskets are.

 

Cheers

 

This was my understanding as well from when I looked into it - as it seems more a question of when you will need a rebuild not if ;) Bottom end and rods I think? are forged as standard and you're best off going for Wiseco pistons, Cometic head gaskets and a Nissan full service and gasket kit which I believe is the least Jimmer recommends and budgets for each time.

dont forget to add that when you rebuild the engine the added cost of new turbos as it would be silly not to replace them at this stage??

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