just blew my 2nd headgasket = /

[Alex91Mk3]

:3d_frown: well well, i changed my hg roughly...less than a year ago. with the nice metal gasket...i turned on my car 2 days ago and ofcourse the sweet smell of coolant accompanied by thick white smoke. This is the third 7m-ge that has a heart attack. :3d_frown: The original, on my way to Orlando from Miami. Oil pump gave out, rod went through the bottom of the block. :3d_frown: 2nd one the water pump broke and burned it. :3d_frown: The 3rd...this one...got bhg...changed it..with metal one...now got bhg again... very sad moment in my supra's life. anyways, should i throw in the towel or give it one last shot? 1jz maybe?:3d_frown:

 

[plaaya69]

When you put the head gasket on did you do any work to the cylinder head or the block?

 

[miekedmr]

you need a proper surface on the block and head. try again, do it right.

to be more specific:
resurface head
lap the block
use ARP stuff and torque to 80ft lb or so with moly on the threads (bottom if they're bolts, top if they're studs)
make sure you have good balanced injectors and are getting the right air/fuel to each cyl, and not detonating in any of them.
make sure the tune in general is good (ignition timing)

 

[Alex91Mk3]

When you put the head gasket on did you do any work to the cylinder head or the block?

yeah ofcourse, took the head to a shop to get it resurfaced. The block i didnt do much to, except clean it real good. torqued the head to required lbs. did everything right. pretty pissed:3d_frown:

 

[tissimo]

that sucks..

 

[jdub]

Depending on which MHG you used, the RA spec can be as low as 30. Both the block and head have to be decked to the RA spec.

What kind of MHG, was it new, and did you use a spray sealer on it?
Did you use ARP bolts or studs?

 

[plaaya69]

I pretty pissed about my supra also because I just bought a jdm motor but after I installed the engine I found out that the engine had a bhg so I took off the head and cleaned the block and put on a stocker and then it blew again but now i'm going to do the head work and the block work and throw a 2mm mhg on it but if I were you I would just try and fix the head gasket but if you prepare the block you should be good because some people who use a mhg and do the head work but dont do the block and it get away with it but you might have problems later down the road.

 

[Reign_Maker]

torqued the head to required lbs.

What do you consider "required lbs"???

I pretty pissed about my supra also because I just bought a jdm motor but after I installed the engine I found out that the engine had a bhg.

I've said it once, Ive said it a hundred times: ANYTIME you buy a "JDM" motor or ANY used motor, ALWAYS tear it apart and prep it... I've heard more stories of this than I can remember and it always amazes me that people just automatically assume that the motor is "low mileage" so therefore it MUST be good... Its a painful lesson to learn...

 

[Alex91Mk3]

Depending on which MHG you used, the RA spec can be as low as 30. Both the block and head have to be decked to the RA spec.

What kind of MHG, was it new, and did you use a spray sealer on it?
Did you use ARP bolts or studs?

Yup, of course it was a new MHG. think it was hks, spent some good cash on it.. spray sealer was used, followed everything by the book. and i used bolts. grr... this thread pissed me off lol damn:3d_frown:

 

[spinningheadboy]

My question is why would you put a metal HG on a 7M-GE? You should put a stock toyota gasket on it and torque it 72 ft lbs. Putting a metal HG on a NA with no turbo and no block prep is asking for a BHG (and is a waste of money).

I'm I missing something?

cwd

 

[Jeff Lange]

Yup, of course it was a new MHG. think it was hks, spent some good cash on it.. spray sealer was used, followed everything by the book. and i used bolts. grr... this thread pissed me off lol damn:3d_frown:

If you didn't machine or deck/lap the block, it's no wonder it blew. Both the head and the block need to be done, not just the head.

If you didn't do the block, you didn't do everything right.

I say grab a new OEM HG, throw it in with 72 ft-lbs, and you should be fine.

 

[spinningheadboy]

If you didn't machine or deck/lap the block, it's no wonder it blew. Both the head and the block need to be done, not just the head.

If you didn't do the block, you didn't do everything right.

I say grab a new OEM HG, throw it in with 72 ft-lbs, and you should be fine.

Sounds like a good advice to me.

cwd

 

[miekedmr]

I'm pretty sure you shouldn't have used the spray sealer either. They don't get along with the viton coating. There was a nice thread about it, with some debate, and then some actual facts.

 

[jdub]

That's why I asked about the spray sealer...the thread you mentioned is a sticky in the Turbo Tech section.

I don't think the use of a sealer is the cause in this case since it's an NA were talking about, I agree with Jeff...the block should have been decked for a MHG. The sealer could be a contributing factor though.

 

[becauseican]

After my 3rd 7m BHG I swapped in a 1jz................

 

[Nick M]

The block must be flat on any headgasket, metal or not.

 

[Facime]

I pretty pissed about my supra also because I just bought a jdm motor but after I installed the engine I found out that the engine had a bhg so I took off the head and cleaned the block and put on a stocker and then it blew again but now i'm going to do the head work and the block work and throw a 2mm mhg on it but if I were you I would just try and fix the head gasket but if you prepare the block you should be good because some people who use a mhg and do the head work but dont do the block and it get away with it but you might have problems later down the road.

Holy run on sentance Batman. The problem with people using MHG's is that they think the majority of blown gaskets come from erosion around the combustion chambers. Its really not the case. If you blow a head gasket at high pressure thats one thing. But starting your car in the morning only to discover you have a blown head gasket is more likely head warpage from high temps and/or improper installation or removal.

The original poster mentions right in his post that he didnt prep the block by doing anything more than "rubbing it clean". Im sorry but if you think thats "doing everything right" you need to let someone else repair your car this time. Or you need to stop ragging on it like its a rental car. Ive been driving cars for 25+ years and have yet to EVER blow up a motor. Ive trashed my share of clutches, trannies and rear ends, but never a motor. You need to stop treating the engine like its disposable and I bet you find they last a bit longer.

I hope my reply doesn come off as harsh, I dont mean it to be. Its just that I see sooooo many of these kinds of threads and 9 times out of 10 I can tell almost immediately why the motor fall down and go boom.

I hope that you give it another try. Im pretty sure you are learning something new everytime you tear into it. Given enough time and experience eventually you'll find your repairs lasting longer. My last bit of advise is that if your going to use a metal head gasket go through the trouble to properly prep the block and head. Personally I dont think using a mhg is the right choice for you. You may want to look at alternatives. There is nothing wrong with the stock gasket if installed properly and torqued right.

 

[Facime]

I say grab a new OEM HG, throw it in with 72 ft-lbs, and you should be fine.

:word8kn: