1987 Turbo engine out servicing quesitons?

[professorbob]

I have a 1987 7MGTE with 116,000 on the odometer. I have pulled the engine and A430E transmission as a unit to do some service work. Questions: Transmission questions to come... Engine.... I pulled the turbo and exhaust header. Will be installing new exhaust studs because some threads pulled loose during removal. Plan on using Helicoils. Any suggestions here are appreciated. Will be replacing the timing belt and idler and the water pump. Again, suggestion here are appreciated. There is some oil in the blower intake. I found a tech on installing new seals. Is it imperative that I locate someone to re-balance the turbines after I install the seal kit? If so where would I find someone that can do the work near Northeast Georgia at I-85 and the SC border? There appears to be no oil leaking from the front crank seal. I am going to pull the crank pulley when I install the new timing belt. Is it imperative that the crank seal be replaced. Is there anything that I need to look for during the belt replacement. On the Head... When I run a compression check and there is good compression on all cylinder should I re-torque the head nuts to 75lbs. If so what is the bolt pattern sequence and pull up amount to keep a good seal. I want to clean around the spark plugs and get the oil out the seeped from the valve cover gaskets. There are four large caps with allen sockets about 12 inch. Will these come out to allow removal for the black plate over the plug spaces between the valve covers without causing any problem with the head? Overall this car is in excellent shape. I am the second owner as i purchased if form a friend. and my goal is to keep it stock and make it our daily driver. Thanks for any suggestions you can provide. Buoyantly Prof

[bgrieger]

First, Welcome. I'll answer where I can:

helicoils: they tend to work alright for some, but many also find the 10mm helicoils don't have enough "bite" and strip themselves quite easily too. One solution is the driftmotion stud replacements, where you end up using a dual ended 7/16 stud: coarse thread for the head and fine for the manifold to allow accurate torque setting.

timing belt, idler and water pump: visit your toyota dealer for parts.

turbo balance: yes, they need to be balanced. Oil in the intake may be turbo, or blowby gasses, or both. Dump out the intercooler as well as it will slowly fill up if you see it in the intake pipes. No idea on shops local to you.

crank seal. If it leaks replace it. If no, I wouldn't. You can if you want though.

during belt replacement, look for leaks, seeps and anything else unusual.

75ftlbs should be fine. There is a risk that you will instead of curing the issues, possibly damage the seal and bring the failure on quicker, but nobody can ever really say if the failure was immenent or or due to the retorque.

Search on google for "supra tsrm" to find a copy of the TSRM manual. Copies or links here are strictly forbidden under an agreement with Toyota's legal deaprtment and the owners of TN...

The 14mm hex caps can be removed and will allow you to replace the centre valley gasket. Reinstall the caps even if you toss the gasket!

Hope this gets you started!

Bob

[professorbob]

Thank for the suggestions. I have removed the crank pulley. Almost able to pull it by hand. Just purchased two two bolts to install a pulley remover only needed to turn the center bolt by hand and the pulley slid right off. The lower belt cover cam off and there was just a little belt residue. The belt looked exceptionally good with not cracks or ware noted.
The oil pump seal is damp and I would like to install a new seal. Anything I need to be aware of in removing the sprocket and the seal. What is the best way to reinstall the seal without damage.
Best tool for holding the sprocket for removing the center shaft nut. Also is there a way to check the pump condition. MM measurements etc?

Hoses. There are several 5 inch 90 degree water hoses. Were these pre-formed or just strait hose that was cut to fit and installed. I know there are several form fit hoses and with the exception of the accordion intake hose and a couple in high heat location are in really good shape. I really think they will go back with no problems. Really could use that OEM parts money to purchase other parts.

I have seen several complete gasket kits on Ebay. Any thoughts about which brand may be better. I have basically stripped the exhaust side of the engine and plan on replacing all the gaskets.

Turbo. The blower turbine has a bent leading edge blade. Have no clue how it got that way as this is the first time it has been apart to my knowledge.
Will this cause a failure of the turbine? I saw on on ebay for about 20 dollars, but there again do not know where I could get the thing rebalanced.
There is just a slight side to side end plan in the blower shaft and no back and forth play that I can tell.
I expect that I will need to install a seal kit and that may be quite a challenge.

I will be posting photos soon as I have some in progress shots of the internals around the cam shafts. Very clean.
Cam shaft. What is the best way to determine if the cams need shims.
The car was very quiet when it last ran. Is there a cold dry feeler gauge gap that I can check?

All suggestions welcomed.
Buoyantly
Prof.

[bgrieger]

Originally Posted by professorbob

Thank for the suggestions. I have removed the crank pulley. Almost able to pull it by hand. Just purchased two two bolts to install a pulley remover only needed to turn the center bolt by hand and the pulley slid right off. The lower belt cover cam off and there was just a little belt residue. The belt looked exceptionally good with not cracks or ware noted.
The oil pump seal is damp and I would like to install a new seal. Anything I need to be aware of in removing the sprocket and the seal. What is the best way to reinstall the seal without damage.
Best tool for holding the sprocket for removing the center shaft nut. Also is there a way to check the pump condition. MM measurements etc?

I hate to admit, but I've never replaced one myself. The pulleys I find are easily removed with a strap wrench around the pulley, and an impact on the nut/bolt. Quick and simple.

For the oil pump, it can only be inspected off the car. You would have to pull the pan, remove the pump assembly and check it with feelers. Body clearance to gears is a max .2mm, gear backlash is .9mm, and side clearance (the gear ends to a flat bar laid across the pump opening) of .15mm. The relief valve should also be able to slide under it's own weight.

I've sent you a pm regarding the rest of it with detailed instructions.

Originally Posted by professorbob

Hoses. There are several 5 inch 90 degree water hoses. Were these pre-formed or just strait hose that was cut to fit and installed. I know there are several form fit hoses and with the exception of the accordion intake hose and a couple in high heat location are in really good shape. I really think they will go back with no problems. Really could use that OEM parts money to purchase other parts.

All are pre formed at their angles. Not all are actually 90 degrees, some are as much as 110 (didn't measure myself, but read something the other day on it.) If you'rez good with your parts guy at napa or others, you might just be able to find cheaper alternatives or similar hoses from other cars. No guarantee though.

Originally Posted by professorbob

I have seen several complete gasket kits on Ebay. Any thoughts about which brand may be better. I have basically stripped the exhaust side of the engine and plan on replacing all the gaskets.

Toyota has a full engine gasket set. You'll have kittens when you hear the price, but I haven't heard anyone that had good to say about the ebay kits. The Toyota kit is very specific on what it contains. The gaskets from turbo to elbow is not included, nor is the throttlebody and idle speed controller...so I found out the other day...If you are only tearing some of the parts down, you might be cheaper ordering the gaskets a la carte.

Originally Posted by professorbob

Turbo. The blower turbine has a bent leading edge blade. Have no clue how it got that way as this is the first time it has been apart to my knowledge.
Will this cause a failure of the turbine? I saw on on ebay for about 20 dollars, but there again do not know where I could get the thing rebalanced.
There is just a slight side to side end plan in the blower shaft and no back and forth play that I can tell.
I expect that I will need to install a seal kit and that may be quite a challenge.

Many suck little pieces of sand, dust, rubber or other over time and the fins get damaged. I would just keep running it if you didn't notice any problems. If you need to replace it down the road, you could get a used one cheap enough, or send it out for rebuild then. rebuild requires rebalancing as well, and you are likely just as cheap to get it all done at a shop as you are to peice things together at the end of the day, and you have something of a warranty in most cases.

Originally Posted by professorbob

I will be posting photos soon as I have some in progress shots of the internals around the cam shafts. Very clean.
Cam shaft. What is the best way to determine if the cams need shims.
The car was very quiet when it last ran. Is there a cold dry feeler gauge gap that I can check?

If you are in this far, will you be removing the head? If so, you should be sending this engine out to prepare for a metal head gasket. Even if you don't want to upgrade on power, the metal gasket properly done is a virtual guarantee that it will keep humming as long as you want it too!

[professorbob]

I do not intend to remove the head as there is not indication of a blow gasket. However, I would like to do a compression check. I read the process and it calls for warming up the engine. I am wondering if I can get an accurate reading cold as it would be so much easier to check it while on the engine stand. I would think that a low cylinder would show up even without the engine being warm. I have no reason to suspect that there is any problem, but would like to discover it here, rather than after reinstall in the car. I thought I would re-torque the head and then run the test. Any suggestions on how much at each turn I should try to pull down on the head to get to the 74 lbs recommended. I printed the tightening sequence off the web. Any idea about what a good accordion hose would run for a replacement? Thanks again for all your input. Prof.

[bgrieger]

There is no generally accepted way to increase torque. Some recommend backing off each bolt and pulling it through in one pass, others suggest not backing them off and coming up 5 ft/lbs at a time. There may be a "true" method, but I haven't seen it. Just the process of changing the torque in theory could cause the gasket to shift and, the seal to break too...there are just a ton of variables and methods out there.

Compression test off the car is tough...what would you crank it with? It needs starter type speeds to get an accurate read.

Accordion hose is quite reasonable new from Toyota as I remember...of course, reasonable is relative...I just finished putting in a $220 order for 2 new rad hoses and a few gaskets...