ZZW30 Head removal query/ oil consumption

[Rosscar]

My year 2000 MRS is using about a litre of oil per 600 km . I purchased it in January this year and after reading the forums removed the precats (which showed no sign of disintergration).The car has now done just over 100.000km. Can anyone tell me if it is possible to get the head off without removing the engine? Also I have read that Toyota modified the pistons in 2002.It has been suggested that the problem may be due to glazed bores.Purportedly my car was brought in from Japan in 2002 with only 4500km on it. Is it possible to fit the later pistons or modify the standard ones ? I would be grateful if anyone has experience with this issue .The car is so excellent otherwise it would be worth fixing the oil consumption problem.

[JasonFriday13]

Can anyone tell me if it is possible to get the head off without removing the engine?

Yes. Mechanics do this all the time to replace head gaskets.

Also I have read that Toyota modified the pistons in 2002.It has been suggested that the problem may be due to glazed bores.Purportedly my car was brought in from Japan in 2002 with only 4500km on it. Is it possible to fit the later pistons or modify the standard ones ?

You don't know what you are dealing with until you take the head off and have a look. Dealing with replacing pistons generally means refreshing the whole bottom end, which can cost between $1000 - $2500. And that's if the head has no damage.

That oil consumption is pretty bad, my hatchback has done just over 200,000km's and it uses 1 litre every 10,000km's. Chances are it's had detonation and has taken chunks out of the piston, and this has in turn scratched the bore. So usually when you accelerate, some oil gets pushed out the oil breather and back into the air intake and burned. And when you aren't accelerating, there is a (relative) state of vacuum in the piston chamber and some oil gets sucked in and burned.

I would suggest getting a compression test and/or leak down test done, this will tell you which cylinders are good and which are bad.

That's bad luck having engine troubles like this. Usually it's a sign that it's been thrashed previously.

[Rosscar]

Thanks for the info that it is possible to get the head off in situ but looks a bit difficult to get at the inlet manifold bolts perhaps best to remove the head with the the manifod attached,As you say you dont know what you are going to find but I dont think this car has been thrashed--It has had two women owners in Christchurch and the engine runs very sweetly with plenty of power and makes no smoke just chews the oil.My other question was to find out what modification Toyota made to the pistons --maybe just enlarged the drain holes behind the oil rings? The suggestion has been made that cars that have done low milage in Japan were never run in properly and hence have glazed bores but it does seem to have been a problem with early 1ZZs.Does your hatchback have a 1ZZ?

[JasonFriday13]

Does your hatchback have a 1ZZ?

No, it's a 4E-FE.

Before you get into pulling the head off, I would suggest getting a compression test and/or leak down test done, this will tell you which cylinders are good and which are bad. Then you can decide if it's worth rebuilding, or buy another used engine and swap it in (there's a couple on trademe for under a $1000).

What I mean by thrashed is that it was done in Japan before it was imported. My sister was a victim of this with her freshly imported car. She had to do rear bushings and ball joints, axles had already been replaced once, and the clutch started slipping not long after she sold it to my Mum. I did the clutch replacement in the garage. That's also when I found out about the worn synchromesh rings, especially in third gear. Redline MT90 fixed most of that.

[Rosscar]

It sounds as if youve had some experience with a w30 then. Im a home mechanic but approaching 70 and notso flexible to get into tight places anymore! I will dig out my compression tester before I do anything.But im fairly sure the engine is in reasonable shape.It would seem from utube videos the oil rings get gummed up and a compression test will only test the compression rings which cant be bad -I get 42mpg on a trip.I was mainly interested in finding out about the piston modification Toyota intoduced in 2002-3 on the 1ZZ,Toyota cant tell me the difference only that the part no. has been superceded.I thought it might have been enlargement of the drain holes behind the oil rings and so could drill out the ones I have if that is the case. However the car does have one other problem in that the sequential gearbox has a slight graunch on changedown 5th to 4th.(i suspect it must be a worn synchro ) It was reccomended to me to replace the oil with ATF by several mechanics which I did -it didnt make any difference however in the 20 000Ks I have done since has got no worse! Do you think the redline would help? Im not in a rush to fix the ring problem but would like to find out as much as I can before I tackle it. Cheers Ross

[JasonFriday13]

However the car does have one other problem in that the sequential gearbox has a slight graunch on changedown 5th to 4th.(i suspect it must be a worn synchro ) It was reccomended to me to replace the oil with ATF by several mechanics which I did -it didnt make any difference however in the 20 000Ks I have done since has got no worse! Do you think the redline would help?

Forth gear crunching isn't really that bad. I would be more concerned about second or third crunching. Yes, Redline MT90 will help, especially on worn synchros. It's expensive but it's GOOD stuff.

I did some google searching on this oil consumption problem, and found this page (about two-thirds down): http://toyota-club.net/files/faq/04-01- ... fe_eng.htm.

[Rosscar]

Thanks for that link it tells me a lot of what i needed to know and while it doesnt sound too hopeful and ill just have to pour the oil through it, do you know for sure that the head comes off with the engine in place! Toyota PN say they take the engine out to work on it and it looks too tight to be able to get the inlet manifold off.It actually looks bad even to get at the alternator if one had to! Perhaps one would have to resort to cutting a hole in the bulkhead if one was desperate !!!

[GDII]

It's far easier for a mechanic to drop the whole engine. Even Jason and I would drop the engine to do this sort of work as to replace the pistons and rings it's pretty much a full tare down. Not that I can do this sort of work yet.

Having the engine out and bolted up to an engine stand means you can remove all the bits you need to, flip the engine over to do work on removing the pistons and doing any work to the bores if required then put it all back together and put the engine back in. Sure, you could do the work in the car but the amount of time and effort to leave it in is not worth it.

[JasonFriday13]

Yeah, doing major work like pistons and bearings, it's better to drop the engine out and use an engine stand. But then again I would probably get an engine shop to install the new pistons and rings into the short block (that's outside my skill range).

[Rosscar]

point taken ! is it nesercary to drop the subframe to get the engine out?

[GDII]

I'm not sure with the ZZW30 but I wouldn't be surprised if you did have to remove it. Engine only comes out the bottom.

[EssDub]

*takes a deep, long breath*

OK.

1) Getting the head off the 1ZZ in the car is a pain in the ass. you have to drop the assembly down, tilt it forward, then pull it out. Its easier to drop the donk onto a pallet jack and wheel it out from underneath as a unit.

2) Its a 1ZZ - its always gonna use oil

3) For the cost of rebuilding a 1ZZ, you can have 8500rpm of fury and almost 70% extra power.

4) The Nov 2002-onwards motors had redesigned oil control rings and the rings were located further down from the crowns, to lower oil consumption. It is NOT a cure.

5) Spyders with supposed 'undisturbed' precats almost always get babied around towns and CBDs. This is bad. You are bad for doing that.

6) C5x/C6x are notorious for munching 3rd/4th syncromesh gears. Its just the way they are. I'm yet to see one over 150000kms old that hasn't got a chewed tooth or three...or eight...

7) MT90 is shit if you already have a problem. You can get Penrite semi-syn oil and some oil stabilizer to do the same (if not better) job for half the cost.

ATF in a C5x? Shoot the mechanic.

9) Engine and box drops right out - don't touch the subframe or experience a world of pain realigning everything.

10) I like shorts. They're comfy and easy to wear.

[GDII]

Spoken like a true ZZW master!

[Rosscar]

Thanks essdub for that info--if new rings aint gonna cure it Im best to just keep pouring it thru then? The mechanic that suggested ATF had done a gearbox overhaul on a w30 he said the bearings were shot in it ,had got the actual box overhaul at a PN gearbox company who reccomended ATF and a friend of mine who is a retired Ford mech said they used to use ATF in falcon gearboxes to stop them shitting bearings.So I rang the gearbox outfit and they agreed would be ok otherwise i woudnt have changed it.Youtube vids of guys fitting new rings say they cured the oil consumption (but for how long?) It would seem from your post that fitting the later pistons is not worthwhile then.

[JasonFriday13]

Basically it boils down to two options:
1) Keep putting oil in it for however long you keep the car for (basically wasting money).
2) Put the later pistons and rings in it (high initial cost, but should pay itself back in a couple of years).

As for gearbox oil, yes ATF is used from the factory, but Toyota started seeing worn synchros so they changed it to a full synthetic API GL4 fluid, usually 75w-90.