MickyG's MX-73 to 7M-GE Swap

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
No, not planning to anymore. My main concern now is whether it's going to be something that can be machined out or if the bore's no good at all.

I'll have to get it torn down enough to take it to a machinist to see what the damage is. Until then, I can still have fun doing the teardown!

Here's the marks I mentioned and yeah, you can see them in previous pics but I've hilighted them to make it easier to spot.
 

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mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Assuming it is the 1st and from what I can see so far, that's probably a safe assumption. The block surface looks very rough but I don't know if that's because I don't know what to compare it to. Might have been decked once before.
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Probably a stupid question and feel free to tell me to search but does a 1st oversize require an oversized piston or is that just if you're going way OS? I know the rings will need to be OS.
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
I like it - thanks for setting me straight! The pistons on this motor at least appear to be OK so I'd hate to have to shell out for new ones.
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
:nono: I know... It makes sense, I mean there is a definite tolerance between the piston and bores that must be maintained...
 
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mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Thanks Allan! I'll continue tearing this one down and see how bad the damage is after it's stripped and let you know.
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Aussies are some of the most friendly people in the world - I should know, I married one!

Ian, Allan, Miggles, not to worry, you're quite safe!

Today:
Finished tearing down the busted 5M from the old soarer. I've learned a lot from this excercise. This motor's a 5M-GEU and has EGR on it (My current 5M doesn't) but it's also older than mine, has a square tooth cambelt (as opposed to my round tooth one) and the older style square cross section fuel rail.

Yeah great, so what, it's busted! That's where things are pretty cool (for me at least). The guy who gave it to me said it was seized and that he suspected oil starvation. Thing is, every part I pulled off was massively lubed and easy to get off, no discolouration in any of the parts, that sort of thing. It stunk but it'd been sitting for who knows how long. Anyway, I pulled the crank off today and found the culprit - #6, big end, spun bearing. I've never seen one of these before and man, was it impressive! The bearing had turned into what looked like wax and was in 4 pieces just sorta smeared onto the crankshaft rod journal. Cool! Needless to say, the crankshaft's probably totally useless now (too bad the rest of it was perfect!).

The rest of the engine looks really good and I was especially impressed by the condition of the block. The cylinder bores were very clean but probably too much so, I really couldn't see any crosshatch left on them.

And if anyone's ever asked, yes the 7M block is different to a 5M - the ribs between the cylinders are fatter in places on the 5M and would have to be machined out to allow the extra width of the 6M/7M counterweights. Probably much more expensive than getting my 7M decked, bored and prepped for OS pistons/rings!

So that's pretty much it for today. I'll hopefully get the crank out of the 7M this week and see what we have to work with.

Love this stuff!
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Yikes! So few updates that I was in the middle of page two!

Not much to report here, I'm afraid. The last few weekends and available weeknights have been spent trying to diagnose and fix my noisy Cressida (top end noise). At this point it looks like it was just valve noise, as cleaning out the oil pressure regulator for the hydraulic valve lash adjusters got rid of it! No rod knock here! Do I have to use a connecting rod to knock on wood to make sure I don't jinx myself now?

I was having a quick chat to my bro over the weekend and discussing various options for restoring this motor. We ended up talking about the wiring harness that's on this motor and was concerned about integrating it with the cressida wiring, as well as the A43DE transmission I hope to keep using. I wasn't sure what connectors on the harness would connect where and he asked me to post some pics to see if he could help.

We suspect this is an A/T motor, which would be easy to adapt to my setup.

So here goes. If anyone else can identify some of the connectors I've labled, that'd be great!

Edit:

Removed pic, because it's in the next post of mine.
 
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miggles

i wasnt speeding officer
Jun 3, 2005
526
0
0
48
perth West Australia
ok, ive had a scratch on the head n worked out some of the plugs,lines,wires.

1 this is the line that runs into a metal hardline to the powersteering pump.(90% sure on this but it is something to do with the powersteering idle up perhaps?)

2 Look for the plug with a blue wire with a white stripe/line. Thats the one for the thermos fan so if u find it then you know thats the one. The others are for aircon and flux capacitor.

3 these are your grounds for the ecu. Ground them into the intake manifold bolt. (remove bolt and poke through eyes and then tighten)

4 Clip goes onto holder indicated :naughty:

5 Auto tranny,reverse lights,neutral start switch. Looks like they have been bypassed from factory.

6 This is the heater vsv. On supras they are located on the firewall where the loom enters the enginebay.

Hope that helps.
 

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mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Thanks heaps Mik! I actually had the vac hoses and ground straps sorted but the others were a huge help!

I had no idea the supras came with a flux capacitor!

As for the thermos fan, I have a glass lined thermos in the house but it's got no electrical connector on it so I'm stumped. :p The only other fan is the hydraulic one and I didn't know that had any electrical inputs on the supra (so still stumped).

"poke through eyes" eh? If you say so, but it sounds painful!
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
I should have done this before to avoid confusion but didn't have a proper jpeg editor at my disposal.

Here's a revised pic with numbers on the things I'm unclear about. Miggles' already provided an explanation on no8 but I'm still not totally sure about the rest. Actually, 5, 6, 7, and 8 have been identified collectively. If I can get an idea of what 5, 6, 7 are specifically, that'd help a lot. As mentioned on page 1 of this thread, I intend to mate this to my older A43DE and I'm sure some connector modification is going to be in order, so any specifics on the existing connectors is going to go a long way to making this job as painless as possible.

Then again, if I run into problems, it gives me an excuse to go manual. Doh, did I just say that?
 

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NashMan

WTF did he just wright ?
Aug 5, 2005
4,940
17
38
43
Victoria BC
dude your green arrow looks like a pennis

miggles said:
ok, ive had a scratch on the head n worked out some of the plugs,lines,wires.

1 this is the line that runs into a metal hardline to the powersteering pump.(90% sure on this but it is something to do with the powersteering idle up perhaps?)

2 Look for the plug with a blue wire with a white stripe/line. Thats the one for the thermos fan so if u find it then you know thats the one. The others are for aircon and flux capacitor.

3 these are your grounds for the ecu. Ground them into the intake manifold bolt. (remove bolt and poke through eyes and then tighten)

4 Clip goes onto holder indicated :naughty:

5 Auto tranny,reverse lights,neutral start switch. Looks like they have been bypassed from factory.

6 This is the heater vsv. On supras they are located on the firewall where the loom enters the enginebay.

Hope that helps.