7M-GE repairs

[Stupid_fast]

I'm going to do some repairs on my Toyota Cressida with l-6 3.0L 7M-GE and A340E automatic. It has a few issues, and I had a few questions.

 

I'm replacing the cylinder head gasket and changing the engine/trans filters/oil and coolant. I am about to order an OEM cylander head gasket set, is there any difference in life/performance of the gasket material? The kit comes with a graphite one.

For the transmission it says I need dextron-III only, would any brand that claims to meet this spec work? For the engine I think its 10w30 in the manual, that is whats in there now, should be fine?

 

The problems I've been having are oil leaking into one of the spark plug cavities(the one for cyl 5&6) on the head, A burnt oil smell if I push past 4000RPM(Trans oil overheating?), and general performance is erratic, some days will perform great, other days and its sluggish. The transmission oil is burnt/discolored. The engine oil leaks, Have to fill ever 1-2 weeks, becomes dark/discolored over a short time.

 

The car has 121,000 miles, was suppose to get an oil change at 118k's or 2 months ago(oops...). 7M-GE engine is also in the non-turbo MKIII supra's, they are known to blow head gaskets at about 100,000 miles because they where not torqued enough from the factory.

 

 

Any help/tips/suggestions are appreciated. I've never changed the oil myself before.

 

 

^Oics included...

[lil89ram50]

you've never changed the oil your self... and your going to replace the head gasket on this motor... hmmm get your self a manual, and follow every step very carefully

[Stupid_fast]

you've never changed the oil your self... and your going to replace the head gasket on this motor... hmmm get your self a manual, and follow every step very carefully

 

I have the repair manual for the car. And yes, I'm a noob, only one way to learn.

[lil89ram50]

im not saying dont do it, and i do encourage it, just take your time, and be organized. make sure to follow the torque sequences too. 10/30 should be good in there. change the tranny fluid too. when you tear it apart, look for the problems. look for leaks, and replace the bad gaskets while its already apart. oh and give us pics of it gettin done :)

[metalmonkey47]

Well you REALLY need a manual then! Just be slow, don't force things, and if you have any trouble with anything or you think something isn't going right, let us know ASAP so we can make sure nothing is going wrong.

 

I've always said that the best way to learn is through hands on experience, so more power to ya!

[Stupid_fast]

Cool thanks, I'm usually pretty good at doing things right the first time.

 

Also should give me some good experience for when I have to get my 510 running.

 

EDIT, Is there any sort of gasket sealer or anything I need to get besides the gaskets? Or just slap them on and call it good?

 

Also I've head people get their cylinder heads ported, is this expensive? Do I take it to a machine shop for this?

 

Thanks for any info...

[bananahamuck]

I run dex/merc trans fluid in my wifes 88 7m-gte (owned about 12 years) with no probs.I think that the toyota head gasket kit is really spendy but it did have EVERYTHING in it when i did her old 87 7m-ge.....which then developed a rod knock 6 months later...

[Stupid_fast]

I run dex/merc trans fluid in my wifes 88 7m-gte (owned about 12 years) with no probs.I think that the toyota head gasket kit is really spendy but it did have EVERYTHING in it when i did her old 87 7m-ge.....which then developed a rod knock 6 months later...

 

Thats an A340E I'm guessing. :P

 

Good info, thanks. I do prefer N/A engines for some reason. I'de go ITB's if I had the cash.

 

 

EDIT, for the picture nazi's.

[shancerlelby]

cool, i also own a cressida! Toyota has revised the headgasket since the bad oem original headgasket fiasco. Felpro ones are the updated style also i hear. On the valve cover i seem to remember some funny "o" ring type seals that keep valve cover oil from weeping into the plug galley. Which i believe are an oem only part. Best sugggestion is to find a manual for that is 7mge related. I have found tons of good inline 6 info over on http://forums.toyotacressida.net/forums/index.php and as a bonus their fake forum for those who arent registered is amazing! I encourage anyone to check some of the posts out! lmao!

[Skib]

and start changing your own damn oil :P

[Stupid_fast]

cool, i also own a cressida! Toyota has revised the headgasket since the bad oem original headgasket fiasco. Felpro ones are the updated style also i hear. On the valve cover i seem to remember some funny "o" ring type seals that keep valve cover oil from weeping into the plug galley. Which i believe are an oem only part. Best sugggestion is to find a manual for that is 7mge related. I have found tons of good inline 6 info over on http://forums.toyota...orums/index.php and as a bonus their fake forum for those who arent registered is amazing! I encourage anyone to check some of the posts out! lmao!

 

Hmm well I just bought some kit off ebay it should be fine. Your 81 still has the stock 5M-GE(?) in it?

I was not sure what was causing the oil leak.that kit probably comes with those O-rings you described, Hopefully replacing those stops it.

 

If anything I'm just hoping for a little performance gain in the low end after the repair job, and to feel comfortable pushing the car to 5800RPM shifts without issues. (changing the throttle cutoff cable tightness actually effects the shift points!)

If I get some better suspension, it does nicely for autocross.

 

And yes, I know not to push it too much for a freshly rebuilt head until I re-torque the bolts at 1000-or-so miles...

and start changing your own damn oil :P

 

There is always a time of beginning...

[MikeRL411]

My daughter had a Toyota 4WD pickup with the problem of oil leak into the sparkplug wells that you describe. You really need the "O-ring" seals! It also helps to degrease the mating surfaces on the head and valve cover, coat both sides of the "O-ring" seal and position on the block and valve cover with Aviation Form-a-gasket number 1, non hardening. Leave the parts held together by gravity for a few hours to insure that the sealant flows across the sealing surfaces and then incrementally increase torque on the retaining bolts to full specified torque. This cleared my daughter's oil leak and is probably what you need.

[Stupid_fast]

My daughter had a Toyota 4WD pickup with the problem of oil leak into the sparkplug wells that you describe. You really need the "O-ring" seals! It also helps to degrease the mating surfaces on the head and valve cover, coat both sides of the "O-ring" seal and position on the block and valve cover with Aviation Form-a-gasket number 1, non hardening. Leave the parts held together by gravity for a few hours to insure that the sealant flows across the sealing surfaces and then incrementally increase torque on the retaining bolts to full specified torque. This cleared my daughter's oil leak and is probably what you need.

 

Cool, good to know. Is that stuff is different from gasket maker?

[Shonuff]

dont know the M series myself, but i gotz teh link

 

http://www.toysport.com/technical%20information/7m_tech_notes.htm

 

 

theres a ton of info here http://www.celicasupra.com

[bananahamuck]

My daughter had a Toyota 4WD pickup with the problem of oil leak into the sparkplug wells that you describe. You really need the "O-ring" seals! It also helps to degrease the mating surfaces on the head and valve cover, coat both sides of the "O-ring" seal and position on the block and valve cover with Aviation Form-a-gasket number 1, non hardening. Leave the parts held together by gravity for a few hours to insure that the sealant flows across the sealing surfaces and then incrementally increase torque on the retaining bolts to full specified torque. This cleared my daughter's oil leak and is probably what you need.

YES! always use a thin coat of aviation gasket sealer --good call

[shancerlelby]

naw my 81 had a 5me sohc inline six. booo. but i had an 85 supra for parts. If i could have found a 7m i would have swapped it, in a heartbeat! Hopefully those o rings are. they do get heated up on most of the 7m's to where they are rocks and don't seal anymore. Buddy had a 7mgte and it had about a litre in the plug valley, no wonder it had a miss.

[Stupid_fast]

Thanks for all the info. Picking up the rest of the stuff I need tonight then I'm going to start on it tomorrow.

 

I just found my favorite look for a cressida...

http://www.boostcrui...post&id=1097313

not mine...ofcourse

 

Wonder how long it takes to break in the new head gasket? I have heard I should run little or no anti-freeze for the first 1000 KM's(620 miles? I should run distilled water, and not tap am I correct?), then flush the cooling system and put original amounts in there. Also torque down the head bolts again at that time.

 

And how to avoid not blowing anything up during this time? I've heard I should not push it at all until after the re-torque, and everything is good.

 

Offtopic: I wonder how much it would cost to have a 2.5" exhaust system installed?

[Stupid_fast]

I started on things today, I drained the coolant(which had a brown tint) The engine oil(which was completely black), and the transmission oil(which was dark brown)...

Also replaced the transmission filter, the trans oil pan is back on with gasket sealer and everything.

 

I tried to get to the oil filter for the engine, but the exhaust manifold is in the way which I need to take off to remove the head anyways. Sadly its the only part that is rusted on the car, which means that the bolts are also rusted on. I got two of them off tapping the wench with a hammer, but the third one is in between the engine and manifold, so its ridiculously rusted and stuck and I cannot get enough space to hit it hard with the hammer. Any recommendations for this?

 

pics after someone gives me an answer.

 

Going to just keep hitting the wench with the hammer tomorrow until it comes off.

[nismo dr]

I'm not familiar with this engine, but on most Nissan's you can unhook the exhaust from the manifold and pull the head with the manifold attached. Then you can get to the bolts much easier with the head on the bench. Rusted exh mani studs have a habit of breaking

[Stupid_fast]

I'm not familiar with this engine, but on most Nissan's you can unhook the exhaust from the manifold and pull the head with the manifold attached. Then you can get to the bolts much easier with the head on the bench. Rusted exh mani studs have a habit of breaking

 

Sorry I worded it wrong, the ones attached to the head are removed fine. It bolts up to the exhaust system only about 15 inches from the head, so the manifold is easily(unless rusted) removed. I'll get a pic tomorrow. I just sprayed a shit-ton of WD-40 on it... Maybe that will help.

[flatcat19]

Follow instructions. Buy a nice torque wrench. Maybe, get a cam pulley holding tool. Use quality parts. Use labeled Zip-Loc bags to store your parts as you take them off. And while you have the head off, get it machined. 7M's, as you've heard, had BAD head gasket problems. A warped head is not unheard of. Take a straight edge to the block while you have it off too. You asked about head gasket material-Multi-Layer Steel. Cometec* makes the head gasket in all sorts of thickness. Not only does it give you a quality gasket-but you can tune your compression ratio a little. And the best piece of advice you're going to get-ARP or Toyota head studs/bolts. Do not trust anything else. GL. Remember-take your time to do it correctly. It takes less time to do it right the first time, than it does to do it twice.

[Gary]

ive got an X8 too :D love that thing! first thing i did to it was a headgasket swap, bit fiddly on the intake side but otherwise not so bad

 

the reason they all failed was incorrect torque settings from factory. gaskets and how the rest of the engine was built were fine :) they got them all in for a retorque after a while but the damage was already done, aside from a few freaks, most of them failed

 

i did mine a few years ago, then removed it and replaced it with a 1JZ, and gave the 7M to a mate who had a not so healthy cressida himself. still going strong in his :D most people i heard from at the time said without decking the block the headgasket repair i did would only last 12months or so

 

quick process of how i did it;

removed the head

sent it to a machine shop to get it checked and faced

bought a genuine headgasket and genuine head bolts, not cos im a brand whore or anything, just wanted it done as good and proper as i could without decking the block

coated the headgasket in hylomar which is a jointing compound, someone told me it already had some of that on the gasket but i thought perhaps it could do with about 3x more :D

the head was nice and clean, but the block needed work, so with lots of solvents and removers and stuff i got most of the old gasket and other stuff off the block surface, then got into it with razor blades to get it as clean as possible

i didnt deck the block, obviously, but if you were to get the 7M back to what it should have been, and back to toyota reliability you'd need to do that, which practically means a full rebuild while you're there

slapped it all together, torqued it up properly this time (i cant remember, 72ftlbs rings a bell but MAKE SURE YOU GET THE RIGHT SETTING) and was away

 

my run in was 1000k's (most of the time taking it verrryy easy), first 100k's i checked the head bolts, at 500k's (i think) i backed them off, then retorqued them to spec. DONT run coolant for the run in period, its not good for the stuff on the headgasket that makes it bond. i just used water from the tap, im not sure about demineralised water myself, might want to look into it more. after you've run it in, use coolant :)

 

if you dont deck the block, its not really a spot on repair, so even after its run in i wouldnt be giving it too much. mine was fine with the odd boot-full and learning about oversteer here and there but if you're thinking about racing it i'd look into either a better repair (either full rebuild, or try ARP headbolts) or a better engine :D 1JZ's are nice and easy to convert, 1UZ's are the shit though!

 

if you need any help just say

[shancerlelby]

http://www.serialnine.com/blog/new-pics-and-vids

 

epic cressida. not a bad way to spend ten grand.

[Stupid_fast]

^Thanks for all the info/comments!

ive got an X8 too :D love that thing! first thing i did to it was a headgasket swap, bit fiddly on the intake side but otherwise not so bad

 

the reason they all failed was incorrect torque settings from factory. gaskets and how the rest of the engine was built were fine :) they got them all in for a retorque after a while but the damage was already done, aside from a few freaks, most of them failed

 

i did mine a few years ago, then removed it and replaced it with a 1JZ, and gave the 7M to a mate who had a not so healthy cressida himself. still going strong in his :D most people i heard from at the time said without decking the block the headgasket repair i did would only last 12months or so

 

quick process of how i did it;

removed the head

sent it to a machine shop to get it checked and faced

bought a genuine headgasket and genuine head bolts, not cos im a brand whore or anything, just wanted it done as good and proper as i could without decking the block

coated the headgasket in hylomar which is a jointing compound, someone told me it already had some of that on the gasket but i thought perhaps it could do with about 3x more :D

the head was nice and clean, but the block needed work, so with lots of solvents and removers and stuff i got most of the old gasket and other stuff off the block surface, then got into it with razor blades to get it as clean as possible

i didnt deck the block, obviously, but if you were to get the 7M back to what it should have been, and back to toyota reliability you'd need to do that, which practically means a full rebuild while you're there

slapped it all together, torqued it up properly this time (i cant remember, 72ftlbs rings a bell but MAKE SURE YOU GET THE RIGHT SETTING) and was away

 

my run in was 1000k's (most of the time taking it verrryy easy), first 100k's i checked the head bolts, at 500k's (i think) i backed them off, then retorqued them to spec. DONT run coolant for the run in period, its not good for the stuff on the headgasket that makes it bond. i just used water from the tap, im not sure about demineralised water myself, might want to look into it more. after you've run it in, use coolant :)

 

if you dont deck the block, its not really a spot on repair, so even after its run in i wouldnt be giving it too much. mine was fine with the odd boot-full and learning about oversteer here and there but if you're thinking about racing it i'd look into either a better repair (either full rebuild, or try ARP headbolts) or a better engine :D 1JZ's are nice and easy to convert, 1UZ's are the shit though!

 

if you need any help just say

 

Cool thanks for the info, but honestly I just want this car to run for another year while I get my datsun running, then I can do a full rebuild and mods. Also I only have the garage for a week, I don't want to push that.

 

I don't even thing the head gasket in this one ever blew up, Its got 121k miles on it, and I re-torqued the bolts at 115k miles. Most of the time I drive the car "fast" I never push it past 4,000RPM's. Its only been through 1 autocross, hit rev limiter ONCE(Yes, it went past the electronic limiter... no idea how) , and only redlined twice before that. Only have one previous owner(They bought it new in 92'!), so I think its in pretty good shape.

 

 

These are the gaskets I got.

 

The only rusty part on the car...

This is where the bolt is... You cant really see it.

 

random,

The old trans oil... I thought it was suppose to be red or something? No wonder its such a fucking slushbox.

 

Oh and fuck, I broke this. What is this part called? I can epoxy it back together, but I'de rather replace it. It goes on the water outlet of the engine where the t-stat is.

 

 

http://www.serialnin...w-pics-and-vids

 

epic cressida. not a bad way to spend ten grand.

Ha, screw serial nine. I can get some cheapo bolt-on coilovers and Koni shocks for $800 from 935 motorsports. :D

[nismo dr]

this is the business when it comes to seized exhaust fasteners