Another engine rebuild...

[jonbill]

Hi -
I joined back in December ( l viewtopic.php?f=75&t=57117 l ) and the car's been under a cover mostly since then.
I've run it a few times over the last couple of months and it was pretty smokey, so when I took it for an MOT this morning, I wasn't surprised to fail on emissions.
I'm assuming it's stuck oil rings, so it's going to be engine out and a rebuild. (probably start in a month or so when I get my Datsun back together and out of the garage).
I've been searching around a bit for manuals & how tos...
I've found a couple that are helpful:

 l viewtopic.php?f=9&t=45332&hilit=engine+removal&start=120 l
 m http://midshiprunabout.org/mk3/2zz-engi ... -a-spyder/ m

Are there any more definitive ones out there?
Are there really no affordable books covering engine removal and rebuild?
I saw this -  m http://www.ebay.co.uk/itm/Toyota-MR2-Mk ... Swf-VWZ2Cz m  anyone know if it's worth the money?
Only other thing I can find is this from the US:  m http://www.ebay.co.uk/itm/2000-Toyota-M ... SwzgRWu5fL m  nearly £200!


Thanks for any pointers!

[Carolyn]

Please excuse the dumb  question...  what colour is the smoke?  Stuck oil rings usually don't show up on the MOT...

[jonbill]

Thanks for the reply - smoke us white with a yellowy tinge, and smells of oil.
What else could it be? Perhaps I'm jumping to conclusions.....

[Carolyn]

Thanks for the reply - smoke us white with a yellowy tinge, and smells of oil.
What else could it be? Perhaps I'm jumping to conclusions.....

Head gasket.  Oil smoke is blue.  Fuel smoke is black. Water is white,,,,

Can be done in car!

I'd run a compression check before starting work.

Just checked - you're in Northants. So am I.  Perhaps I can assist?

[1979scotte]

That would be unlucky its rare on the 1zz as far as i am aware.
Not known it in the 2 years ivde been a member.

[cabbydave]

If you do decide to rebuild your engine I will pm the fluid's name for cleaning the carbon out of the piston grooves. Don't forget you will have to hone the bores

[jonbill]

Ah HG would be preferable to piston rings! It just made sense to me that oil coming past the rings would be an emissions failure.
How does hg failure lead to emissions probs?
Anyway, I'll check the compression and report back - all help gratefully received.
Just driving it to and from the MOT with the roof down was quite addictive.

[Carolyn]

Ah HG would be preferable to piston rings! It just made sense to me that oil coming past the rings would be an emissions failure.
How does hg failure lead to emissions probs?
Anyway, I'll check the compression and report back - all help gratefully received.
Just driving it to and from the MOT with the roof down was quite addictive.

Lot's of oil burners make it through the MOT. Mine did.   Head gasket failure - water in the cylinder (pus possibly oil from the oil way), lousy combustion, low compression, Emissions fail.
Has it been overheated?
I'm only guessing in an educated way.. The compression check should show a leak between two cylinders if it's a head gasket.

[jonbill]

Makes sense. Don't know if it's been overheated. Guy I got it from reported intermittent misfire but said otherwise good. (It's not misfired for me though and temp sits solidly at 12 o clock).
I'll be back....

[Carolyn]

Ah HG would be preferable to piston rings! It just made sense to me that oil coming past the rings would be an emissions failure.
How does hg failure lead to emissions probs?
Anyway, I'll check the compression and report back - all help gratefully received.
Just driving it to and from the MOT with the roof down was quite addictive.

By the time you've got the head off, you're only 45 mins from getting the pistons out.  Engine still in the car.

[loadswine]

Be interesting to hear what the issue is, but, as Scott has said, HG failure is reported very rarely on the 1zz in the Roadster. I can only remember 1 suspected instance of it being reported on here in 12 years, and that car had an issue with many things, the HG was not conclusively proven on that one if I remember correctly.

[beavisrules]

Thought I posted  this one earlier , but there's a 1zz video on a corolla which is pretty much the same , but back to front.
 m https://www.youtube.com/watch?v=A595LR4SQpI m
not sure the mr2 will be fun without ramps and personally would remove the engine to do anything more than a belt or gasket on it.

[jonbill]

Thanks everyone. I'll report back in a few weeks when I get some room in the garage.

[Mr X]

I have 2 threads on here, one I rebuilt my engine with a deglaze +new rings (not hone as mine wasn't burning oil and cylinders were ok):
http://mr2roc.org/phpBB3/viewtopic.php?f=11&t=49521&p=571639&sid=b255aa6693a391915a9ee9e9e9343e50&sid=b255aa6693a391915a9ee9e9e9343e50#p571117

and this one on replacing the head gasket:
http://mr2roc.org/phpBB3/viewtopic.php?f=11&t=50245&p=636048&hilit=replace+head&sid=b255aa6693a391915a9ee9e9e9343e50&sid=b255aa6693a391915a9ee9e9e9343e50#p578203

I live in Raunds, northamptonshire if you need a compression tester I have one if you want to do a quick check sometime and need a hand.

[jonbill]

Thanks - I hadn't found them, so I'll have a good read.

[Carolyn]

Looks like my educated guessing was probably incorrect. I'm working on a pre-facelift that's putting out whitish yellow clouds (copious ones).  It is, in fact, loads of unburned fuel.  It's at its worst when the engine is partially up to temperature. I haven't yet got to diagnosing the root cause.  I'll post on this thread when I get there.

[jonbill]

Thanks- that does indeed sound similar to mine. Fingers crossed it's something simple

[Carolyn]

so far ruled out:

Head gasket, MAF, Fuel over-pressure from pump, O2 sensors.  Got a spare fuel rail and injectors, which I know are good, so I'll swap that lot next.

[Carolyn]

I have gone through the lot.  Found nothing out of spec but it's still being very messy exhaust-wise What was the specific emissions failure?  Was it an item on the emissions test or was it rejected because it was making so much smoke/steam?
At the moment I'm leaning towards a sodden water-logged muffler that needs a damn good long run to dry it out.  This car had stood for quite a while before I got it and had not had a proper run for months.  My Honda civic 1.6i would look like it had a blown head-gasket for a few days after it had been allowed to stand for a couple of months. Especially in winter.

[jonbill]

I can get the actual values from the emissions test when I get back to Northampton on Thurs. It failed on more or less all the emissions tests - high CO, high HC and lambda.
My car certainly has been standing for months. Most of the time under a cover. But it has been very damp hasn't it!
perhaps I could try taking the silencer off and take indoors for a few days to dry out.

[ChrisGB]

Temperature sensor?

[Carolyn]

I can get the actual values from the emissions test when I get back to Northampton on Thurs. It failed on more or less all the emissions tests - high CO, high HC and lambda.
My car certainly has been standing for months. Most of the time under a cover. But it has been very damp hasn't it!
perhaps I could try taking the silencer off and take indoors for a few days to dry out.

No need to get the actual values.  We may or may not have the same problem.... I'm going to drill a small hole in the bottom of the muffler and give it a chance to drain.  I'm in Rushden.  I could pop over, take a peek and we can compare.  Perhaps we'll both learn something.  Have you run a compression test?

[Carolyn]

Temperature sensor?

Not in my case... but good thought.

[jonbill]

No need to get the actual values.  We may or may not have the same problem.... I'm going to drill a small hole in the bottom of the muffler and give it a chance to drain.  I'm in Rushden.  I could pop over, take a peek and we can compare.  Perhaps we'll both learn something.  Have you run a compression test?

Sounds good. I  haven't done a compression test yet - I hope to do that on Friday. You'd be very welcome to come over and have a look. I'll be around most of Friday, Sat, Sun.
(edit: more than welcome, I'd actually be very grateful!)

[jonbill]

Update on this:-
Carolyn came round on Friday with a compression tester & more.
Compression was good - 185 to 190 PSI so no HG problems. Carolyn said that's above OEM figure, so indicates some oil getting past the oil rings.
I went for a long drive to dry the exhaust packing. It was still smoking at the end of that, although when I rev it now there's a distinct blue tinge to the smoke.
It smokes strongly after overrun - which I think indicates valve guides/stem seals. Carolyn suggested PCV valve could also cause this, esp. since it doesn't smoke at cold start.
So.. I'm currently awaiting a new PCV valve and we'll see where that gets us.