Engine replacement queries

[Batfink40]

Hi all.

Had my 2004 MR2 for around 7 months now and love it. Unfortunately I seem to have bought a bit of a duffer engine wise.

I hear it's a reasonably common issue but it's using oil like it's going out of fashion. I'm guessing due to ovaling.

As far as I can tell I'm not getting big plooms of smoke from the pipe and the precats has been removed way before I bought it.

I've no plans on getting rid so am looking to replace the engine. I'd like to avoid another MR2 engine if at all possible to avoid the potential for the precat problem on the donor engine.

In short 😂😂😂😂 if I buy a 2004 celica with the 140bhp engine as a donor, am I likely to be in the same situation down the line or is this solely an MR2 issue?

[Carolyn]

The Celica,along with the Avensis and the Rav4 all have the 1zz engine.  Which is the same engine as in your two.

Unless you want to spend thousands, you're best to either put in a replacement rebuilt 1ZZ or have yours rebuilt.

The ovaling thing is a myth, pretty much. The oil consumption is down to piston rings stuck in their grooves 90% of the time. As it's not a smoker, it probably has not ingested bits from the pre-cats..  New rings and a good honing will make a massive difference.  These engines with stuck oil control rings generally don't smoke.

You won't really know if your engine is a good candidate for a rebuild until it's opened up. But that's not a big deal, as it has to come out anyway.

[JB21]

If you can fit the engine yourself would a 2zz not be the better option?

[Carolyn]

If you can fit the engine yourself would a 2zz not be the better option?

A LOT more expensive for a decent result.

[Joesson]

If you can fit the engine yourself would a 2zz not be the better option?

A LOT more expensive for a decent result.

I can't see much sense in replacing a worn (1zz) engine with a ( worn) 2zz with likely no reliable history.

[james_ly]

How much oil? At the point where you have a oil 'milkman' delivering for you? Or just top up every time you fill the fuel tank?

[Batfink40]

Cheers for the comments guys. I was thinking the 2ZZ engine but that would involve a custom exhaust system as well right?

Basically the car goes from full on the dip to min on the dip within 2 weeks depending how sensibly I want to drive.

Unfortunately most of my driving is a daily 30 mile round trip on the motorway so granny driving isn't an option.

I'm concerned that putting another 1ZZ in is spunking money up the wall for potentially finding the same issue a couple of weeks down the line.

A rebuild could be an option but about as costly as buying a donor car.

[Beachbum957]

There was a time when finding a low mileage donor engine wasn't too hard, but the cars that used 1ZZ are all getting older, so most engines will be high mileage.  Ones that aren't may be engines that were in cars that were sitting for long periods (such as a wreck), and unless the engines were properly prepared for storage (unlikely) they may have storage related issues, such as corrosion, corroded/stuck rings, etc. 

If the engine you have isn't damaged (no failed bearings, etc), and the issues are stuck rings or normal wear, a rebuild may be a better option if done properly.

[Carolyn]

Cheers for the comments guys. I was thinking the 2ZZ engine but that would involve a custom exhaust system as well right?

Basically the car goes from full on the dip to min on the dip within 2 weeks depending how sensibly I want to drive.

Unfortunately most of my driving is a daily 30 mile round trip on the motorway so granny driving isn't an option.

I'm concerned that putting another 1ZZ in is spunking money up the wall for potentially finding the same issue a couple of weeks down the line.

A rebuild could be an option but about as costly as buying a donor car.

I've rebuilt a few of these.  Start with an engine that is not truly dark brown/black inside (it's been very badly neglected).

A Set of rings, rod bearings (if needed) a good honing, new valve seals, lightly lap the valves (don't grind the seats) clean the piston grooves, add a couple of extra oil-holes. New head gasket and bolts.

The crankshafts are tough, do plastigauge to check for wear, but it's rarely a problem.

While it's out, a new water pump and thermostat, 'cos you'd be mad not to.  Oh and might as well put in a new clutch

Parts cost around £300. If you have to pay someone else it's around £350 - £400 for engine in and out and about £250 -£300 for the labour on the engine.

The 2ZZ swap requires at least twice the expense for a decent result. All used 2ZZ engines have been thrashed so they will need a good going-through plus many who do these recommend gearbox work, Mind you, quite a few have done it and are very pleased with the result.