#MR2sday engine update - Holy Piston!

"SidewaysOnDirt still misses Bowie" (sidewaysondirt) 04/19/2016 at 11:25 • Filed to: mr2sday, mr2, 4age, aw11, engine builds, project car hell

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It’s #MR2sday and I got a bit of work done and learned a bit more about my old 4A’s past. I’ve mostly been cleaning ancient disgusting parts, and no one wants to see a picture of a throttle body in a bucket of diesel fuel, so I’m skipping that (amateur-tip - Harbor Freight has an all-metal washing bin you can pick up for like $80 with a pump and will easily fit a 4A head and intake plenup with room to spare; amateur-tip 2 - gank the drain plug and attach a hose with a valve on the end instead so you can empty it without making a mess). For the previous teardown stories and pics, !!!error: Indecipherable SUB-paragraph formatting!!! and !!!error: Indecipherable SUB-paragraph formatting!!! .

The head’s off and soaking in diesel. It’s going to be taken apart this week probably, but in the mean time I’m getting started on the bottom end. So far it’s been easy, but I’m going to have to look into a couple of spots. The crank bridges took more torque than I was expecting to remove. Being a stretch bolt, they didn’t “break” like normal hardened steel ones would. As I started loosening them, it actually felt like I was stripping them as the resistance recused more gradually than I was expecting. I took the wrench off a couple of times just to make sure that I was in fact turning the bolt instead of stripping it.

None of the bridges themselves just fell out. They needed a bit of coaxing, but nothing major. Apart from the center one which has a pin, I was able to pull them by hand.

EDIT - !!!error: Indecipherable SUB-paragraph formatting!!! , number your bearing caps. I didn’t. Luckily, he found a handy !!!error: Indecipherable SUB-paragraph formatting!!! again if you fuck up like I did.

I’m going to consult the BGB on this before taking pliers to them juuuust in case.

As you can see, I forgot to take pictures while pulling the pistons. They’re easy. It’s a 12mm 12 pt socket. Takes a ton of torque to pull off, so use a breaker bar. Crank wear is practically nonexistent.

Some time during this I noticed that the head gasket was still on the block. It was so dirty that I didn’t even realize it was still there until I moved it accidentally. I now realize just how addicted to gasket sealer or radiator repair crap one of the previous owners was. There’s fucking mountains of the shit where there should be openings for coolant.

There were supposed to be holes to get it into the head that I couldn’t even see. The gasket is now hanging on my wall to use as a visual example for anyone who wants to use that stuff. It also brings me to my next point...

The pistons are out! But wait a minute... Enhance!

Enhance!

Shit. As far as internals go, this is the first sign of trouble I’ve seen. I knew it was losing compression when I bought the car because it was burning oil and I suspected it was blowby because of how dirty the oil got and how quickly it happened. I didn’t think there was an actual hole in the piston.

I don’t think that this is the cause of my failure. I’m putting that down to the blocked coolant passages. It could be just a hunch, but something about the way it’s worn makes me think that it’s old. Like really old. I’m pretty sure that that’s more of that gasket sealer/compression restoring gunk on the bottom ring. If so, it’s PO damage. Cylinder walls look great, so one shot OEM piston’s damn good so far (wouldn’t be surprised if someone has some spares laying around).

As has been the case so far, bearings are showing almost no signs of wear.

Jareth will now be judging my engine build. I prefer it this way.

crowmolly > SidewaysOnDirt still misses Bowie 04/19/2016 at 11:30

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Did you mark your main caps to keep them in the same order?

RamblinRover Luxury-Yacht > SidewaysOnDirt still misses Bowie 04/19/2016 at 11:34

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no one wants to see a picture of a throttle body in a bucket of diesel fuel

BUT THAT’S MY FETISH

SidewaysOnDirt still misses Bowie > crowmolly 04/19/2016 at 11:35

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Shit. Did not. How much does it matter if the bearings are getting replaced?

crowmolly > SidewaysOnDirt still misses Bowie 04/19/2016 at 11:39

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You may luck out if yours have casting numbers, markings, or are engineered to only go in one spot.

If not, check this out:

http://mgaguru.com/mgtech/engine/…

SidewaysOnDirt still misses Bowie > RamblinRover Luxury-Yacht 04/19/2016 at 11:40

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I always said I’d never kink shame anyone, but I think I might have to make an exception.

Niko's Work Account > SidewaysOnDirt still misses Bowie 04/19/2016 at 11:42

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is this an engine

SidewaysOnDirt still misses Bowie > crowmolly 04/19/2016 at 11:44

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Cool. Looks like I’m going to be learning more than I was expecting. The second method seems like what I’d end up doing.

SidewaysOnDirt still misses Bowie > Niko's Work Account 04/19/2016 at 11:45

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Nope. It’s a collection of parts.

crowmolly > SidewaysOnDirt still misses Bowie 04/19/2016 at 11:50

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Yeah, not the end of the world. I think worst case is a line bore (?)

FWIW I’d replace the main cap bolts and rod bolts with ARP stuff if it’s available. Cheap insurance.

SidewaysOnDirt still misses Bowie > crowmolly 04/19/2016 at 12:04

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Oh yeah. They’re all being replaced. This engine’s actually really well supported. It’s getting a serious track-focused rebuild if the block and head are still good. Probably going to get the head rebuilt and ported by one of the guys who specialize in 4AGE heads. Upgraded valvesprings, big cams, bigger valves, etc.

crowmolly > SidewaysOnDirt still misses Bowie 04/19/2016 at 12:13

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I wouldn’t sweat the pistons then. Toss ‘em.

SidewaysOnDirt still misses Bowie > crowmolly 04/19/2016 at 12:21

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I’m not. Because I have no idea what I’m doing, I was sort of thinking doing a semi-OEM rebuild (at least OEM insides since everything other than that one piston’s great) just to make sure that I don’t fuck up badly. It’s still going to have a standalone ECU, ITBs from a silvertop, etc, but I don’t want to destroy good parts if I fuck up.

uofime-2 > SidewaysOnDirt still misses Bowie 04/19/2016 at 12:29

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that piston looks melted

SidewaysOnDirt still misses Bowie > uofime-2 04/19/2016 at 12:33

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Indeed it does!

TTercel > SidewaysOnDirt still misses Bowie 04/19/2016 at 14:39

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1MZ swap pls.

SidewaysOnDirt still misses Bowie > TTercel 04/19/2016 at 14:46

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Already has a blacktop in there. The old 16V’s getting rebuilt with forced induction and a bunch of Formula Atlantic parts.

TTercel > SidewaysOnDirt still misses Bowie 04/19/2016 at 15:02

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Damn. i will definitely follow this. What do you think of the blacktop? Is it worth the money?

SidewaysOnDirt still misses Bowie > TTercel 04/19/2016 at 15:06

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I’ll find out soon. Just buttoning up a few things. What’s weird is that the BTs and 16Vs are almost the same price now. The STs are still cheap. I’m actually thinking about picking up a silvertop just for extra parts if I find one locally since they’re so cheap at the moment.

MR2_FTW - Group J's resident Stig > SidewaysOnDirt still misses Bowie 04/19/2016 at 15:55

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Save yourself a ton of time figuring out bearing sizes and read my rebuild thread . Bearing stuff starts on page 4. Once you get everything ready to go back together, get ONE mid-size factory bearing (there’s like 5 sizes) and plastigauge it on every journal to see if you need to go thicker/thinner THEN order the rest. Same for rod bearings. The markings on the block are out the window after 200k miles and a polish.

SidewaysOnDirt still misses Bowie > MR2_FTW - Group J's resident Stig 04/19/2016 at 16:10

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Neato! Thanks!

uofime-2 > SidewaysOnDirt still misses Bowie 04/19/2016 at 17:40

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Did all the water passages next to it in the block happen to be blocked?

I’d kind of expect there to be some wall damage too, definitely check the roundness of that cylinder.

Jayvincent > SidewaysOnDirt still misses Bowie 04/19/2016 at 20:03

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seriously nice reporting, you better be careful or Kinja is going to ask you to pay them... keep up the good work and remember to take lots of photos for us to enjoy from the relative safety of our virtual garages

SidewaysOnDirt still misses Bowie > uofime-2 04/19/2016 at 23:31

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I’m going to have it all checked out when I get the head and block trued. Every passage is blocked. The pics don’t really do it justice.

uofime-2 > SidewaysOnDirt still misses Bowie 04/20/2016 at 10:51

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Yikes!

SidewaysOnDirt still misses Bowie > uofime-2 04/20/2016 at 12:56

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There’s a hole on either side of this one to let water up closer to the camshafts. Didn’t even know until I started cleaning it out. The closest thing I have to a before and after for the block is below. You can see how quite a few holes are completely restricted , particularly the ones closest to in between the cylinder walls. Look at the shape with gasket seal crap on the gasket and the shape with the gasket gone. You can kind of see the buildup in the bigger passages, but it’s dark. I can probably get before and after soaking in diesel for the head tonight.

dogisbadob > TTercel 04/25/2016 at 14:58

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NOOOOOOOOOOOOOOOOOOOOOOOOOO

the 1MZ sux! One of my least favorite Toyota engines, and I love Toyota. Not even enough room for it in the Camry, let alone in the tiny-ass Mr2. What a bitch to work on if you ever need to get to the back of the engine.

uofime-2 > SidewaysOnDirt still misses Bowie 10/07/2016 at 14:07

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Got any progress updates on this thing?

SidewaysOnDirt still misses Bowie > uofime-2 10/07/2016 at 14:14

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Unfortunately not. The original engine’s completely disassembled and on shelves essentially. Charlie has the blacktop installed and it’s on the road, but not with me. My brother’s driving it around. I got a job offer in New York, so took it. I’m now paying over ten times as much for my apartment than I do for my storage unit. My brother pretty much took over the space. It now sports a broken but otherwise clean Fiat Spider, a Fiat Twin Cam, and a couple of extra transmissions in it as well now. Some time over the winter I’m going to fly down just to grind rust out of Charlie and seal the bottom. I’m just worried that a winter’s going to finish it off since it’s already rust prone and rusty. It’s being driven, but the old engine’s sitting on shelves in the space and probably will be for a while because I have no place to work on it up here.

uofime-2 > SidewaysOnDirt still misses Bowie 10/07/2016 at 14:37

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I’ve been away for similar reasons and didn’t realize you’d had such big changes! Good luck with the project

SidewaysOnDirt still misses Bowie > uofime-2 10/07/2016 at 14:49

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So far, I’d rather be in New York not working on a project than in Florida with one. I’m sure I’ll figure something out at some point once I get settled and technically I guess I can always fill up my spare bedroom with parts and work on the build there (yes, I have a spare bedroom in New York), but it’s off the menu until I get settled in more.

uofime-2 > SidewaysOnDirt still misses Bowie 10/07/2016 at 15:14

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Good to hear the changes were for the better. I know the creative storage game all to well, I’m still too cheap to pay for renting a garage.

SidewaysOnDirt still misses Bowie > TTercel 12/30/2016 at 09:15

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Worth the money. Similar p/w ratio to my BRZ, but it revs to 8600 and doesn’t seem to want to stop there.