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Discussion Starter · #1 ·
Greetings!

My '91 GT runs beautifully, but when recently changing the 90 deg. pipe from the turbo to the intercooler, (it was cracked at the end and burbling oil near and onto the turbo...stunk like hell at red lights)...it occurred to me that oil shouldn't be in this part of the system at all!

I lose about a litre every 2 weeks, a tad more if I'm pounding it often...my cousin said it was the piston rings. The car has got 310,000 + on it, and appeared to be meticulously maintained when I bought it a year ago...but it keeps getting hungrier for the oil...

My question is: Is it feasable to replace the rings? Maybe do the valves and head gasket while we're there? Or would it make more sense to just grab one of those "complete" Japanese motors with around 40,000 kms from this place in Toronto that imports them and lets 'em go for $800.00 to $1000.00 and get my cousin to give me a hand dropping it in? (He's licensed, got a garage...maybe $300.00 to $500.00 to help me...)??

I love this car...stereo, body, brakes, steering, suspension, acceleration, exhileration!

All help appreciated,

Thanx,

warrlock2000
 

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Discussion Starter · #3 ·
Can't Post JPG's Of My 6!

Greetins!

I can't get my new pictures to be pasted to my replies or my profile...any suggestions? It seems to want an htp address...I don't have a web page!

What's the simple way to get my car's pix out here?

Thanx,

warrlock2000
 

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Yeah probably a bad case of blow by due to wear and tear on old rings.

I know rebel2k4 changed his head gasket and re-ringed his pistons for less than $300 or so, but with your kind of mileage you'd prolly wanna rebuild the whole block and prolly top end.

I think it would cost around $1000 ish to do it yourself.

Might look around for some low mileage engines (good luck though) first.

Unless you're ready to spendy some more serious money and you know what you'll be doing, I wouldn't mess with any JDM motors right now.
 
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Topline sells a complete kit (Pistons, Gaskets, Bearings) for the engine for $399 (or $299, I forget). Add the price to for a bore/hone and your set.

Thats the way rebel did his first rebuild, It cost him $600 or so (from what I read) on his first rebuild, but either he eats engines for lunch, or he made a mistake, because he blew it real quick.

I don't think its Toplines fault, as AdamTurbo has used it on two engines without any problem.

Now back onto the topic, I don't think it is a ring problem, but you can use a simple compression test to see, anything below ~110 psi would indicate leaky rings, or a failed headgasket, but seeing as you don't have those symptoms we can assume its rings.

Leaky rings allow pressure from piston compression to travel down into the crankcase, pushing oil up and through your PCV valve and PCV vent lines. You end up with oil going into the first intake boot hooked onto your VAF and your intake plenum.

Take that boot off, if its relatively clean (I say relatively as any high milage car will have some crankcase blowby) than your problem is not rings.

If the oil starts after the turbo on your intake piping than the problem lies with the center cartridge in your turbo. It is lubricated with a fluid bearing, and if the seals wear out, will start to leak oil into the compressor.

That, in my opinion, is what your problem is. A turbo rebuild is an easy DIY job (Except for balancing the shaft) and a rebuild kit costs ~$100.
 

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Discussion Starter · #6 ·
Awesome Tip!

Greetings!

Thanx for the advice, flyswat...I just put a used turbo in about 2 months back...other one leaked AND burned oil...been wondering if my inter-cooler might be full of the stuff...seems like a bit of a task to get at it...

I'll check the boot (you mean the one that always goes on these cars, the 90 deg. boot at the back, right?)...

As for rebuilding it, I may look in to one of those Japanese engines, complete with turbo, maybe tranny with 40,000kms...you heard much about them?

warrlock2000
 

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Well, it is a used turbo so it could still be that. You should always rebuild a turbo when swapping. Atleast I would never put a used one in. You just never know what might happen.

And as far as I know, either there are few or there are no JDM F2T's at all. Maybe a few but I doubt it. I though all JDM capella engines were FE-DOHC.
 

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FlySwat said:
but you can use a simple compression test to see, anything below ~110 psi would indicate leaky rings, or a failed headgasket, but seeing as you don't have those symptoms we can assume its rings.




If the oil starts after the turbo on your intake piping than the problem lies with the center cartridge in your turbo. It is lubricated with a fluid bearing, and if the seals wear out, will start to leak oil into the compressor.

now this is my question.. since i did a compression test on it and i pulled say.. 150 145 143 138 and lets say my turbo squels loud anything past 4k.. and theres oil in the ic pipes..

now from what i mentioned above..


on cold start it blows a nice cloud of blue smoke.. could it be that my turbo seals aren t blown but do leak oil?

fwiw- the turbo has oil coming out the first cold side pipe.. mounted to the turbo.. it builds up there so i guess thats a definit sign of oil leaking


soo since my car smoke on start up.. JUST REBUILT MY T BIRD UPGRADE AND IM ABOUT TO PUT IT ON MY SIX.. now since im taking the pos turbo off.

do you think it will stop smoking on cold start?

i have a spare head with 69k but it has a chipped valve.. ran perfect before hand.. and im doing the turbo swap this week..


i wanted to keep the stock head on and run the turbo


any advice would be great!

thanks:D
 

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oh and i forgot to mention..

speaking of oil coming out the pvc i have this issue 2.. on both rubber lines coming out of the valve cover..


could the bad turbo cause any of this?
 
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shannonlujan said:
Well, it is a used turbo so it could still be that. You should always rebuild a turbo when swapping. Atleast I would never put a used one in. You just never know what might happen.

And as far as I know, either there are few or there are no JDM F2T's at all. Maybe a few but I doubt it. I though all JDM capella engines were FE-DOHC.
The Cappela GT-R has the FE-DOHC motor, the Cappella GT-X has the F8 motor (1.8Litre FE-DOHC).

Theres a few other variants, ask Blind Freddie.

I'd reccomend buying a used US-spec F2t and dropping it in. The FE-DOHC doesn't come turboed stock, and requires a stand alone ecu to do the swap properly.

You can get a low milage F2t for as little as 200-300 bucks.

Originally Posted by TURBOsix
now this is my question.. since i did a compression test on it and i pulled say.. 150 145 143 138 and lets say my turbo squels loud anything past 4k.. and theres oil in the ic pipes..
Turbo sound is usually caused by worn bearings allowing the shaft to have enough play in it to let the turbines scrape the housing. If they are doing that, theres a good chance that the seals are shot as well. You'll probably notice the majority of your oil problem go away with the T-bird.

on cold start it blows a nice cloud of blue smoke.. could it be that my turbo seals aren t blown but do leak oil?


That sounds more like leaky valve stem seals to me.
 

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Discussion Starter · #11 ·
Bit of an update...

Greetings!

Well, I don't smell oil so much anymore thanx to replacing that rubber pipe to the inter-cooler. And I believe that it is the turbo leaking, not the rings (I had the 90 deg. boot off about 2 weeks ago when replacing the oil line to the turbo-didn't appear to be loaded with oil the way the I/C pipe was) so I'm pretty sure the seals in the turbo are the culprits here...even though I made sure the turbo came out of a running GT!). As a last ditch effort, I put in some Slick 50, and am pampering the engine to keep it in there rather than burn it off with hard driving...short-shifting at 3000 RPM's....haven't lost a drop in a week...boring as hell driving it though...

A new question-what is that doo-dad that branches off the I/C pipe just before it goes into the top of the inter-cooler...there is a smaller diameter pipe running up to it (about 5" long) and it appears to be a sensor of some kind...this smaller rubber hose thingy is now coated with oil, from one spring-clamp to the other...wondering if I fried (drowned?) this thing...what does it do? It has a small rubber hose (outside diameter maybe 3/8") that runs to the rear of the motor...

BTW...a rebuilt turbo runs around $600.00 to $800.00 around here...that's why I have been wondering about a used Japanese engine for around $1000.00...what's with all this talk about FE3 and other weird letter/number combo's describing the various engines these cars will accept...do you have to change the "chip" or anything? I like my vehicles fast, but not too complicated...and the gotta be RELIABLE!

Thanx all,

warrlock2000
 

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Re: Bit of an update...

warrlock2000 said:
Greetings!



A new question-what is that doo-dad that branches off the I/C pipe just before it goes into the top of the inter-cooler...there is a smaller diameter pipe running up to it (about 5" long) and it appears to be a sensor of some kind...this smaller rubber hose thingy is now coated with oil, from one spring-clamp to the other...wondering if I fried (drowned?) this thing...what does it do? It has a small rubber hose (outside diameter maybe 3/8") that runs to the rear of the motor...
Uh, the bypass valve maybe? Thats what it sounds like your describing. It releases boostpressure from the intercooler pipes (when you close the throttle under boost) to protect the turbocharger from backspinning or surging, don't tamper with this thing too much unless you know what you're doing, check the projects for more info).

BTW...a rebuilt turbo runs around $600.00 to $800.00 around here...that's why I have been wondering about a used Japanese engine for around $1000.00...what's with all this talk about FE3 and other weird letter/number combo's describing the various engines these cars will accept...do you have to change the "chip" or anything? I like my vehicles fast, but not too complicated...and the gotta be RELIABLE!
There is not Japanese F2T. The Japanese engine for the Japanese MX-6 (actually called capella or 626 (correct me???) in Europe, Japan, other countries is the FE-DOHC. They two completley different engiens but a direct swap.

In other words, if you're looking for a direct replacement F2T engine, you're not gonna find it in Japan.
 

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I was told by an engine imorter that the F2T were available in Japan:confused:
 
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I think the only person who could give a definitive answer would be Blind Freddie.

The F2T came in aussie-spec and a-spec cars, NEVER came in e-spec cars, not sure about j-spec,
 

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FlySwat said:
Topline sells a complete kit (Pistons, Gaskets, Bearings) for the engine for $399 (or $299, I forget). Add the price to for a bore/hone and your set.

Thats the way rebel did his first rebuild, It cost him $600 or so (from what I read) on his first rebuild, but either he eats engines for lunch, or he made a mistake, because he blew it real quick.

I don't think its Toplines fault, as AdamTurbo has used it on two engines without any problem.
the only things I did wrong my first rebuild was:
A) Used a cheap head gasket. adamturbo blew a topline as well. want me to find the thread? because I will.
B) went too easy on the break in. When I pulled the rings they had absolutely no wear. They were still black metal, not even shiny.

The most recent time I cracked a piston again. I still dont know why. I guess running lean, even with 2 supplemental injectors, a chip mapped for 16 psi, EGT, and 190 lph pump(?) I have a few things in store for the motor when I tear it open again this winter to fix that. Then I'm tuning it on a dyno.
This thread is way off topic but I think he's got more info than he needs. Good luck.
 
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) Used a cheap head gasket. adamturbo blew a topline as well. want me to find the thread? because I will.


Your right, I forgot about that, I've blown two fel-pro's. The next one that goes in will be the mazda OEM one that lasted 13 years :)


The most recent time I cracked a piston again. I still dont know why. I guess running lean, even with 2 supplemental injectors, a chip mapped for 16 psi, EGT, and 190 lph pump(?) I have a few things in store for the motor when I tear it open again this winter to fix that. Then I'm tuning it on a dyno.


One of 992mmx-3t's friends has a motorswapped 323 that was running nearly 25 lbs of boost, he had it tuned nicely and everything and then one day it detonated. Turned out to be a faulty aftermarket (walbro 255) fuel pump.

Check your fuel pump?
 
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