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Discussion Starter #1
And you're going to immediately remedy the head gasket and low oil pressure...(installing new head gasket/arp bolts)

Are there any upgrades/mods you'd do in the process of remedying these two initial problems? (Looking for anything that might be a PITA later, while I'm in there)

Input appreciated in advance
 

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And you're going to immediately remedy the head gasket and low oil pressure...(installing new head gasket/arp bolts)

Are there any upgrades/mods you'd do in the process of remedying these two initial problems? (Looking for anything that might be a PITA later, while I'm in there)

Input appreciated in advance
welcome noobstotheboost

are you taking the engine out ?

that is the first decision. I have done the hg both ways and without a doubt I'm a "pull it out" vote.

x10 if its an original car, aka turbo/manifold has not been off since clinton or bush was in office. shit is going to be all kinds of fun to loosen up...


low oil pressure... can you expand on that. related to HG, almost certainly not causing this. maybe you need a rebuild (large bearing clearances), or maybe pump is shot / needs shimmed. maybe a piston oil squirter popped off, maybe the oil filter/cooling sandwich block is hosed. lots of things that can cause low oil pressure.

how many miles on motor / car

feed us the info lets see what you got (pics)
 

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Discussion Starter #3
So, as of right now no real issues with anything, just basing this off of the stuff I've read claiming once you start ratcheting up the HP the known weaknesses will be oil pressure and head gasket failure.

So my logic is to remedy those first for reliability's sake.

170k on the car, 100% stock/factory

I don't intend on pulling the engine unless I have to.
 

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its just so much easier to pull engine with trans imho. getting the oem 30 year old exhaust off while the engine is in the car is a pain because odds are things are going to be stuck - and you get much better clearance/angles on downpipe/turbo bolts when the engine is out. motor can come out with exhaust split pre-cat (downpipe still on)

if your going to keep the car, you may want to have it out anyway to shim the oil pump / put new rear main seal in / seal entire engine. it may not leak now but when you double the boost and start getting her real hot on some pulls...these 7ms love to puke oil out everywhere if they have 20+ year old seals
 

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Discussion Starter #5
its just so much easier to pull engine with trans imho. getting the oem 30 year old exhaust off while the engine is in the car is a pain because odds are things are going to be stuck - and you get much better clearance/angles on downpipe/turbo bolts when the engine is out. motor can come out with exhaust split pre-cat (downpipe still on)

if your going to keep the car, you may want to have it out anyway to shim the oil pump / put new rear main seal in / seal entire engine. it may not leak now but when you double the boost and start getting her real hot on some pulls...these 7ms love to puke oil out everywhere if they have 20+ year old seals

Very good Information to consider here
 

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I recommend heilcoiling all 7 exhaust bolt holes on the cylinder head as they do like to strip out.

How is the water pipe union bolt on the back of the cylinder head? I recommend replacing it if it looks bad and rusty but do be careful as some have had it break off during removal so some heat and PB blaster might help in the removal process.

There is other mods such as the zulu coolant passage mod and Quake ARP insert mod in which seems to be controversial but you can research those and choose to do them if you prefer. I have done both of these mods to my 7m cylinder head this year and would do both of these mods again if I build another 7m motor.
 

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Who the hell is this 'zulu' guy who just started having his name associated with drilling the missing coolant hole?
This has been going on for decades...

You want good oil pressure back, do a full rebuild, with new bearings.
And why the heck not freshen up the pistons and bores at the same time, grind the valves & seats, check the head for flatness, etc., etc. ?
With that kind of mileage, anything short of a full rebuild is just putting off a soon to show up next failure.
 

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Sounds like he must be from Hawaii but I don't understand where that name came from either. I never really heard of people doing that mod 10+ years ago nor have I really heard of any long term results either from anyone that might have done this mod but I will share how mine goes later on...
 

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I did my first 7M head back in the mid '90s, and saw it somewhere on SupraMainia.
Back then it was just called drilling the missing hole.
'Zulu' is more associated with Africa....
 

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Discussion Starter #11
I'll be honest, I've never been inside an automobile engine. The thought is intimidating (pulling the entire engine)

At any rate, I'm going to YouTube the pull and see how it looks

After I got done going through all the maintenance records, it has a "new" head gasket and bolts less than 15k miles ago. But it was done in 2005...

It also appears a lot of seals have been replaced as well, but I don't know which. It just says "seals" on the paperwork

It does appear to have an existing leak at the back of the valve cover currently.

I'll post some pics of it this afternoon sometime if I get to it.

I bought this as a toy, it's all original - overall needs a lot of shine put into it.

My original goal was to get as much cheap power I could out of it with doing minimal "extra" work, but you guys are making a lot of valid points in regards to reliability.

I'd be pissed if I got it running good and putting out decent numbers, just to go to shit on me shortly thereafter.
 

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Discussion Starter #12
I saw this exposed...what is it? The more I look into this, and absorb the information being provided, I may end up just redoing the engine. I keep finding stuff I dont like. You'll see oil accumulation in several places here
242610
 

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I've already ordered a rear quarter panel section to replace that later. It was cheap, so I went ahead and got it to have. Again - priority #1 is to get it running how I want. Quality of interior/exterior is my absolute last priority
 

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Hybridau, actually is BBB ZooLoo, and he posted this in 2005.
It was actually being done way before that.

Newtoboost, There is no such thing as cheap power, and with 170k, you will be pissed off if you don't tear that thing down, and completely go through it.
 

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Discussion Starter #17

So you guys wouldn't even bother going down this list at all without pulling the engine and complete overhaul?

What happens if you got up to around 340 HP and didn't. Is worst case you start leaking a lot of oil, and then pull the engine? Or are you risking catastrophic consequences?
 

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who knows, if its had a HG and it was done right you may be able to run it for a while. if the car runs and is not puking oil and coolant out, I would enjoy it and start chipping away at things. like cooling system hoses, any rubber hoses, drop the tank/pump and filter. flush all fluids etc. the basics and build from there.

it is a 30 year old car so keep in mind the totality of that. rebuild the motor all bad ass and then realize your entire brake/suspension is junk or your subframe cracks on first hit. fix that and play whack a mole with corroded connectors / ancient switches and contacts. it never ends. thats why you get a lot of "do it once and do it right" around here. cool thing about these cars is they hold their value / are worth more if you improve them (the right way).
 

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Discussion Starter #19
who knows, if its had a HG and it was done right you may be able to run it for a while. if the car runs and is not puking oil and coolant out, I would enjoy it and start chipping away at things. like cooling system hoses, any rubber hoses, drop the tank/pump and filter. flush all fluids etc. the basics and build from there.

it is a 30 year old car so keep in mind the totality of that. rebuild the motor all bad ass and then realize your entire brake/suspension is junk or your subframe cracks on first hit. fix that and play whack a mole with corroded connectors / ancient switches and contacts. it never ends. thats why you get a lot of "do it once and do it right" around here. cool thing about these cars is they hold their value / are worth more if you improve them (the right way).

This is heavily where I'm leaning in my mind, I see it has less than 15k on the head gasket done at Toyota dealership (though I know that doesn't mean anything, my best mechanic is NOT at a dealership)

And "seals" were replaced around the same time. They have the years on them (14 years) but not many miles, or indication of which seals.

I kinda feel like chipping away, making improvements - having fun with it, then if the seals start failing, go ahead and pull it and doing it CLEAN.

I just hate to go right at it and ignore the documentation I have stating some of the weak points have been addressed

If leaking fluids is all I have to worry about from increasing HP/boost through Bolton's, my mind says start chipping away, until weak points start failing.

Then going bulletproof. If I'm pulling the engine, that bitch will be like new when I put it back in. No point in not going all out if you're already doing that much work
 
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