MR2 engine woes

"MR2_FTW - Group J's resident Stig" (MR2_FTW)
04/19/2014 at 23:58 • Filed to: None

The last few weeks it's been having a hard time at cold starts, a little extra cranking to get it going, low initial idle, etc. Didn't think much of it. But today on the way out to the Blue Ridge for a club cruise, it started spitting coolant again like it used to when it had a BHG 3 years ago.

I bled the system and topped it off after the highway drive, and it was totally fine for the spirited drive through the mountains. However on the highway trip home it did it again. This is consistent with the symptoms before: totally fine unless at a sustained constant high RPM for a long time (highway driving).

I'm thinking when I last did the head gasket 3 years ago, I only resurfaced the head. Maybe the block has some slight imperfections that need to be ...

*sunglasses*

....IRONED out....

YEAAAAHHHHHHHHHHH!!!!!!

ANYWAY to do that means engine removal and disassembly which means full rebuild time. New rings, bearings, checked cylinder bores, resurfaced block, balanced crank & rotating assembly, probably ARP main studs and rod bolts, gaskets, timing belt/idler, oil pump, and, if in the budget, maybe an aluminum flywheel while it's out.

All cool stuff but lots of money, and even more pressing to me right now....time and work. I guess it's good I got the wagon back on the road.

DISCUSSION (21)

Bytemite > MR2_FTW - Group J's resident Stig
04/20/2014 at 00:00

I love your car!!!

MR2_FTW - Group J's resident Stig > Bytemite
04/20/2014 at 00:13

Thanks, me too. I'm just mad that I've gotta do this all again after only 3 years.

Bytemite > MR2_FTW - Group J's resident Stig
04/20/2014 at 00:16

Hopefully your example is an exception..The AW11 is my dream car and I am planning on buying one in a year and a half.

BiTurbo228 - Dr Frankenstein of Spitfires > MR2_FTW - Group J's resident Stig
04/20/2014 at 02:41

Sucks that you've got a dead head gasket, but kickass on the rebuild :)

I'd caution against an aluminium flywheel for street use. It's fine in a racecar with a high parts turnover, but with long use on a road car they can walk on their bolts and end up unbalanced. Basically the softer alloy gives way underneath the steel bolts and gives it some wiggle-room.

That's part of the reason I went with a lightened steel one for my Spitfire. It's still 6kg lighter than the old one though :)

Do you think you could stretch to some specialist head porting? I don't know how good the stock ports are, some engines don't need it, but they are very very pretty :)

Reigntastic > MR2_FTW - Group J's resident Stig
04/20/2014 at 11:24

Sorry about that buddy. Have you done an oil change to see if you have any contaminant? Could just be a bad hose or filler neck leaking shit everywhere, I had that happen to my SW20 a few months ago.

Please, please please please: if you do the full teardown yourself take pictures, I might get an MK1 so I can learn how to build engines for the first time.

MR2_FTW - Group J's resident Stig > Reigntastic
04/20/2014 at 12:29

I changed the oil last week and it was fine. I checked the dipstick and filler cap and it looks fine, so I don't think the oil and water are mixing. They didn't last time either, it was just combustion gas getting into the water jacket. If there were a leak, it wouldn't look like bubbles, it would just look like the level going down (when looking at the filler with the cap off)

MR2_FTW - Group J's resident Stig > BiTurbo228 - Dr Frankenstein of Spitfires
04/20/2014 at 12:30

I've thought about it. It really depends on how much everything else costs.

BiTurbo228 - Dr Frankenstein of Spitfires > MR2_FTW - Group J's resident Stig
04/20/2014 at 12:45

Yeah, the more expensive it is the longer the car's off the road. Head porting will be anything from $300-$600 for a 4-cyl. Add that onto the rest of the upgrades and it'll start stacking up quickly.

MR2_FTW - Group J's resident Stig > BiTurbo228 - Dr Frankenstein of Spitfires
04/20/2014 at 13:15

I'll probably leave it then. I had the head gone over last time (valve job, readjusted valve clearances, new stem seals, etc, so I may just set it aside and leave it be. I think I need to not worry so much about performance bits like the flywheel, and spend money on good machining/rings/bearings/bottom end balancing/ARP fasteners instead of relatively frivolous stuff I don't need like flywheel/porting. I think when I take the block in I'll have the machine shop tell me what size parts I need since I can get OEM parts cheaper as an employee than they can wholesale.

BiTurbo228 - Dr Frankenstein of Spitfires > MR2_FTW - Group J's resident Stig
04/20/2014 at 15:17

Yeah, it's a good idea to get the important bits sorted and then use anything spare you've got for fancier stuff. Plus, porting won't do much if you haven't got opened up exhaust and intake as well as a modified fuel curve (or a MAF sensor that will automatically adjust).

MR2_FTW - Group J's resident Stig > BiTurbo228 - Dr Frankenstein of Spitfires
04/20/2014 at 18:02

I have an aftermarket intake, a 20valve tubular exhaust manifold and upgraded downpipe with high flow cat. I'm also running 2 extra psi of boost (10 vs stock 8), and a little magic box of electronics that activates the cold start injector under boost under 3500rpm to make up for deficiencies in the stock ECU. Porting would probably be a good thing, but I'm not about to drop cash on it. If I could do it myself that would be nifty.

BiTurbo228 - Dr Frankenstein of Spitfires > MR2_FTW - Group J's resident Stig
04/20/2014 at 18:31

Sweet, so it's actually a little bit of a hot rod :) I'd definitely check out whether it needs porting at all before trying to get something sorted. I certainly wouldn't attempt it myself, but I have heard of people doing it. Especially simple things like port-matching the intake and exhaust manifolds (taking off any lip disruption flow).

It's something you could do yourself, but without a flowbench or lots of experience it's difficult to tell whether what you've done is beneficial. Bit of a black art.

What sort of power do you think you're making?

unpredictable_swerve > MR2_FTW - Group J's resident Stig
04/20/2014 at 22:09

Are you in the free candy car club? That mk1 looks very familiar

MR2_FTW - Group J's resident Stig > BiTurbo228 - Dr Frankenstein of Spitfires
04/20/2014 at 22:59

I've dyno'd at 151 wheel horsepower. Not bad when it made 145 crank from the factory 25 years ago

MR2_FTW - Group J's resident Stig > unpredictable_swerve
04/20/2014 at 22:59

Yessir.

BiTurbo228 - Dr Frankenstein of Spitfires > MR2_FTW - Group J's resident Stig
04/21/2014 at 07:59

Cool :) so something like 160-175 at the crank. That thing must be a little rocketship, when it's not blowing head-gaskets :S

unpredictable_swerve > MR2_FTW - Group J's resident Stig
04/21/2014 at 14:12

I've seen your car around all the time, I was at fredricksburg all-toyota a few weeks back, anyays back to the subject, try blackstone oil analysis, it's well worth the $25 and they tell you if anything internally is wrong.

MR2_FTW - Group J's resident Stig > unpredictable_swerve
04/21/2014 at 14:22

The oil is fine. No residue whatsoever, same as last time. I think it just blew a tiny little bit into a coolant passage and is blowing compression out just like before.

unpredictable_swerve > MR2_FTW - Group J's resident Stig
04/21/2014 at 14:27

go gen4? If you have the cash for it, it is hands down the best upgrade you can do.

MR2_FTW - Group J's resident Stig > unpredictable_swerve
04/21/2014 at 23:05

Yeah if you have a very large budget. I don't.

unpredictable_swerve > MR2_FTW - Group J's resident Stig
04/22/2014 at 16:06

Hah, I never thought I could afford it either, good luck though man.