The Rebuild! (90T)

[Cyrus]

Hello all,

So I've finally decided to get my Supra back up and running. It's been sitting in the driveway for going on 5 years now (taken for quick spins around the block every month or 2), but I finally want to fix its known problems and get it back on the road as my alternate "fun" vehicle (daily driver is a 4-cyl ford ranger, so I haven't gone above 65mph in years... :nono.

The valve stem seals leak like a bad faucet, and I'm pretty sure I have a minor blown head gasket, as my coolant is a little oily looking. As a weekend warrior, I have never undertaken an automotive overhaul of this scale. I've done simple bolt-ons and replaced belt-driven non-pressurized accessories (alternator, waterpump). Frankly, I am a little frightened of getting started and then being overwhelmed or hitting a brick wall that I can't overcome, but fuck it... I want to get this thing back on the road! I've got my TSRM and a modest tool set...

... so here goes!


Before pics:

 

[Cyrus]

Got through the tear down today. I was planning to take more pictures, but I got into a groove as I was taking shit apart and forgot to keep the camera handy :: hommer ::

here's what it looks like so far...

sans intake piping, upper intake manifold, coil packs and wires, and probably some other stuff...


and here it is after pulling off the head


speaking of the head...


and here is that little thing that goes between the head and the block


this was the most damaged part of it I could see... does this qualify as a BHG?




next up:
remove turbo and exh. manifold from head.
remove lower intake runners
remove EGR and any other bits and pieces from the head.

then the head is off to a machine shop to get cleaned and "rebuilt".

Everything went better than expected! No snapped studs, no stripped bolts, no fluid eruptions... Took about 4-6 hours, but I was drinking beer and taking my time, so I am unashamed.

 

[Turbo_ryde]

looking good! And good luck, lol. Let me know how the valve stem seals go as mine needs to be done on my 7m!

 

[supraguy@aol]

Great job.
A few things i would recommend; use arp studs for the rebuild. They are much stronger and are reuseable.

Use either a felpro or oem head gasket- better design than most replacement gaskets.

Helicoil the exhaust manifold threads. This will allow you to keep factory tension on the bolts, wont strip out, and are very easy to install.

These fixes will allow you to increase boost by a moderate amount if you decide to later, and regardless, will make your motor much more reliable in general.

 

[Cyrus]

thanks for the comments!

ive decided to go with arp bolts instead of studs. someday, when funds are available, my plan is to purchase a motor and build it up properly. take it all apart, clean-up/modify the bottom end as necessary, deck the block properly so i can have a MHG, get a FFIM, etc. when i do that motor, i will likely use ARP studs. for this one, i think the bolts will be adequate.

planning on using a felpro i reckon. i'm a little worried about my compression ratio. im gonna measure the block soon... hopefully it hasnt been decked in the past. and hopefully my head isnt in bad shape. if they have to take very much off, im worried about how using an OEM size gasket will increase my CR. read the head gasket thickness thread here on the boards but i'm still not quite sure how to address that worry. i'll deal with it after i hear how much milling the head requires and after i figure out whether or not the block has already been reduced.

in regards to the helicoil, i was hoping to not have to do this? if i am able to remove the exhaust mani without difficult, and i chase the threads with a tap, will it really be necessary to helicoil?

regarding boost increases, my goal for this motor is 12psi. really though, id be happy with 6 psi as long as my baby is back on the road!

 

[supraguy@aol]

As far as the compression worries- if you dont plan on decking the block during this build, i dont see an issue. I guess you might mean that you're worried about it rising if they cut the head, though?

ARP bolts should be fine for your plans, though i myself wouldn't spend ~$90 on bolts when i could get studs for $25 more, AND i was already expecting to go to studs in the future.

Who knows if you'll be fine without helicoiling? You might be. But if just one stud begins to pull out as you approach 29 ft-lbs, Your exhaust will have a leak. Why not do it now? Its pretty cheap~ $40 for a kit.

 

[Backlash2032]

I wouldn't be too worried about compression rising. I'm gonna be running a block decked 13 thou and a head decked 8 with a 1.4mm gasket. Only bumped compression to 8.9:1

Sent from my HTC Rezound using Tapatalk 2

 

[Cyrus]

right, im worried about how the CR will go up if they take a bunch off the head to smooth/flatten it. and i havent seen any variety in the thickness of composite gaskets. only MHG seem to come in various sizes.

good argument about the studs. perhaps ill rethink that one.

and we'll see on the heli coils too. ill see what kinda shape the studs appear to be in after i get the manifold off.

thanks again for your input, it is much appreciated!

 

[Cyrus]

work continues! got the head all taken apart today...

this is what i found when i took the turbo off... is this bad?




and this is the head after removing all the bits and pieces..



i took off the cam position sensor. not sure if the machine shop will need that or not... hopefully it is ok to remove it. took off as much stuff as i could, really. seemed like the right way to go.

here is my pile of parts to date





feeling pretty happy with my progress thus far. it has been mostly smooth sailing. had my first minor hurdle today; one of the nuts on the exhaust manifold heat shield rounded off on me. was able to use a file to cut 2 clean faces into it and then popped it off with a crescent wrench.

supraguy: as i was removing the exhaust manifold, 2 of the studs came off with the bolts. if i were to just purchase 2 new studs, is it still a good idea to helicoil the stud holes in the head?

also, can anyone tell me how to properly install studs? i have the 2 on the exhaust side of the head, and also 2 of the studs came out of the turbo where the elbow attaches to it.


next step: waiting for the machine shop to call me back. was hoping to talk to someone today to get an estimate and make an appointment to drop off the head, but they didnt answer and havent returned my call yet. what other parts can i ask them to clean for me? i am hoping they have a chemical bath safe for aluminum, and that they will clean the upper and lower intake manifold for me. also gonna ask if they can clean the cast exhaust manifold in a hot tank.

as always, thanks for reading and please, if you have any comments or suggestions, share them. for the most part, this is me:

 

[Cyrus]

so im getting ready to purchase some stuff for putting the car back together... what do you guys think of this list

1) felpro head gasket kit ($290). i heard Toyota has a similar kit but havent been successful finding a price for it online. anyone know anything about this?
2) arp head bolts ($100)
3) timing belt ($35)
4) water pump ($55)
5) silicone hose kit ($280)

what is the best way to procure various nuts and bolts? i would like to replace most of the fasteners on the hot side of the engine, as they are pretty rusty/crappy looking. is it worth it to pull out the studs that remained in the head/turbo and replace them?

thanks!

 

[supraguy@aol]

Great work so far.
As for your studs- it's not uncommon for them to unscrew from the head. Just remove the nuts from them.
Check the threads of the studs- is there any aluminum in them? If not, you might be ok. Make sure the threads are clean and well oiled.
Or, you can get new studs from the dealer, along with new manifold nuts(I recommend this- they aren't too expensive.) You can do a test install of the new studs with the manifold, to see if the threads will hold:
Install the new (or cleaned)studs with some thread locker into the head. Then place regular nuts onto the stud, and tighten them against one another. This will allow you to use a wrench to tighten the stud the rest of the way into the head. Then remove the nuts. Install the gasket, manifold and exhaust nuts on the head, and see if you can get to 29ft-lbs. If so, great. If not, buy a helicoil kit.

 

[supraguy@aol]

PS- It's literally only $10 more for head studs. Just sayin.

http://thmotorsports.com/i-61534.as...MENT&utm_campaign=GoogleShoppingSeanNOFITMENT

 

[Cyrus]

awesome, thanks for the info about the exhaust studs. one additional question... you mentioned i can put the nuts against each other and then screw the stud into the head. is there a torque figure i should aim for at this stage? or maybe do i just keep turning til all the threads are inside the head?

and regarding my reticence to deal with head studs... i have read that one must remove the cams to be able to get a socket around the nuts on the studs towards the rear of the head. i am hesitant to take the cams out after everything is all put together. i havent really looked into it, but it seems like a bit of a process, especially with reassembly. my goals for this motor are well within the limits of the arp head bolts, and thus they seem like the easier option while being more than adequate in terms of reliability. if i'm wrong and the studs are just as easy to install as the bolts, then i'd probably go for that option.

 

[supraguy@aol]

I've never had a problem tightening or loosening the rear(or any) nuts while it's in the car.
I can tell you that it takes a narrow socket to loosen or tighten in general, but the only thing cam-wise, is you haveto rotate the cams a bit in order to torque/ loosen all the nuts.
I think one thing people don't like, is that you have to put the head on, and THEN install the studs, when you're dealing with the motor while it's in the car. But yes, you're right.
There's no need for studs at the moment, with the goals you have in mind.

As for torque figure on installing the exhaust studs- no. You just want them in as far as they'll go and somewhat tight, but don't go crazy. The use of studs is so that the clamping force is on the nut, not in the head's threads.

 

[CyFi6]

Another drawback of the studs is you MUST use a thread chaser to clean out all the bolt holes in the block and blow them clean before using studs otherwise they will not thread down far enough.

 

[Cyrus]

so i talked to the machine shop today... $450 for a valve job, which seems reasonable. pressure test, hardness test, crack inspection, resurface, 3 angle valve grind, replace seals, calibrate valve height and spring pressure.

unfortunately, a valve adjustment runs an extra $340. is this something i should try to tackle on my own, or is it better to have the professionals do it (this is at a machine shop i completely trust)?

 

[Cyrus]

got a couple of other quotes for the valve job/adjustment. seems the DOHC w/ shims and buckets setup is a bit of a bitch to adjust. lots of labor hours required. $700 was the average, so I guess the first quote I got of $800 was reasonable after all. the $800 guy has experience with 7m's and building race motors, whereas the cheaper quotes came from machine shops that do more of the everyday average engine work. the cheaper ones said they dont ever check aluminum heads for hardness and also used some rudimentary/non-scientific method for testing the head straightness (something about removing the valvetrain and then putting the cams back in and spinning them. if they spin freely, the head is straight, if not it is warped. :weak

i'm just gonna bite the bullet and let the pro w/ 7m experience tackle the refresh and adjustment for me. waiting for my new valve stem seals and cam seals in the mail, and then the head is off to the shop.

took my manifolds (upper/lower intake, exhaust) in to get jet washed, and they offered to bead blast the exh mani for free, so that's cool. looking forward to getting them back so fresh and so clean.

 

[Cyrus]

got my eristic gasket set in the mail today... gotta be honest, i am a little disheartened and am feeling very nervous about using any of these gaskets on my car. the paper gaskets look so cheap and flimsy and shitty. makes me wonder about the quality of the rubber gaskets as well.

i am starting to think that maybe this was $40 burnt, and that i'll just bite the bullet and get the gaskets i need straight from the toyota dealership. these gaskets dont look to be anywhere near the quality/properties of the gaskets i pulled off the car when i was taking it apart. am i being paranoid?

i am already getting the EGR cooler gasket, the head gasket, and an exhaust manifold gasket from toyota... what else should i get from them and avoid from the eristic kit?

 

[Cyrus]

got my manifolds back from the machine shop after having them jet washed and bead blasted.

here are before photos:




and after:


went ahead and coated the exhaust manifold and elbow with some ultra high-temp paint.



also spent about 4 hours today with toothbrush and rags degreasing little bits and pieces. got my valve covers cleaned up, cleaned the fuel rail and injectors, cleaned the afm and air filter, the 3000 pipe, and various other goodies. still got a shitload of cleaning to do, however.

finally figured out the schedule for the head work. taking it to the shop on monday, hope to have it back friday, just in time to do some assembly over the weekend. hoping that the better quality gaskets, new hoses, and ARP head bolts get here by then.

 

[Cyrus]

so i thought i was gonna get this rebuild done for under $600-700.

boy, was i kidding myself.

i'm at $1700 so far.

head work - $800
ARP bolts - $100
Hose Kit - $280
Cleaning Service/Products and Tools - $200
Gasket Kit - $50
Replacing important parts with toyota OEM (timing belt, water pump, tensioner, injector o-rings, cam pos sensor cover, head gasket, egr cooler gasket) - $300

shit adds up awfully fast...