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Old 04-16-2010, 05:02 PM   #1
cvbikeguy
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so it finally happened. after trial and error countless times i believe my head gasket finally blew. as some of you may now i did a rebuild of my 7mge. now at 270 miles i was on the freeway and smoke was dumping out of the car. engine and interior was fludded with smoke. 30 seconds after it stopped. i was pretty much home so i drove it the rest of the way. parked it and double checked my temp and pressure. both were fine.

after a couple hours watching tv and debating i realized that my oil pressure was inconsistent in the past couple days. i go back out there and turn on the car and the "birdcage" signal pops up. yea and of course it all clicks. i look in my radiator and see poop in there. BHG

so now im just trying to figure out what to do and what caused this. i have arp bolts in and never pushed the engine too much. so do i rebuild it again and start from scratch? or do i sell and move on. it doesnt help that i dont have anyone in the area to help with the build. any advice is welcome.

thanks
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Old 04-16-2010, 07:58 PM   #2
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sorry to gear that man...but 300 miles is Way too soon for youto have not done something significantly wrong..... only three possibilities come to mind: improper torque,cracked head or block; or the lower timing belt cover was not cut with the block.
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Old 04-16-2010, 08:10 PM   #3
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Sorry to hear that man, ive got a new headgasket if you need it
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Old 04-16-2010, 08:29 PM   #4
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did you chase the head bolt threads with a tap? torque in multiple passes and in the right order me?

as long as the head and block aren't warped I'd redo the HG.
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Old 04-16-2010, 08:38 PM   #5
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even though i followed the tsrm i just wonder if i just f'ed something up of whatever. also i didnt get the new head machined but i did buy a rebuilt one on ebnay for $400 and it says it was already shaved and ready to be slapped on. you think i might have messed up on the head bolts?
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Old 04-16-2010, 08:59 PM   #6
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Quote:
Originally Posted by kamikazemkiii View Post
Sorry to hear that man, ive got a new headgasket if you need it
how much? thanks

Quote:
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did you chase the head bolt threads with a tap? torque in multiple passes and in the right order me?

as long as the head and block aren't warped I'd redo the HG.
whats chase and tap? couldnt find it in the tsrm
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Old 04-16-2010, 09:04 PM   #7
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Did a shop rebuild the engine for you? I know a person who got there motor rebuilt, and the shop torqued the head bolts at the wrong torque, because it was listed wrong in the manual. He even told them to change the torque because it is a problem, but I guess they did not believe him. In the end the tech had to rebuild the motor at no charge, but they bought a replacement instead I guess cheaper. It took some time to get it back, but if some one did this to you, you can get it at least get it fixed at little to no charge.
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Old 04-16-2010, 09:11 PM   #8
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Quote:
Originally Posted by suprabahamut View Post
Did a shop rebuild the engine for you? I know a person who got there motor rebuilt, and the shop torqued the head bolts at the wrong torque, because it was listed wrong in the manual. He even told them to change the torque because it is a problem, but I guess they did not believe him. In the end the tech had to rebuild the motor at no charge, but they bought a replacement instead I guess cheaper. It took some time to get it back, but if some one did this to you, you can get it at least get it fixed at little to no charge.
no i actually did it myself and torqued them down to 80lbs. but i think cre might be right about the chase and tap. too bad i dont know what the hell it is.

hey cre would i still be able to use my arp bolts?
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Old 04-17-2010, 02:20 AM   #9
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Chasing threads is a pretty standard practice. You get a tap (thing used to thread holes for bolts) of the same size and pitch of our headbolts and you thread it into the holes (and keep adding oil to lubricate and clear out debris). As you thread it in AND as you thread it out it cuts the metal of the threads back to the right shape and size for the bolts/studs. Not doing this may cause the bolt to reach a given torque level but not provide the actual axial clamping force you want (ie: the shit don't turn so easy so you think it's done too soon).

I really wish they made hollow studs for our cars.... that's the only way to get really close to a given clamping force. Hollow's are great.

Yes, the headbolts are reusable.

80lbs is high... don't go over manufacturer specs just becaust you think it'll be better... you'll break something.

Also, rebuilt of not, you don't know what shape the head was in... could have warped from inappropriate storage. Measure it with a machinist's straight edge (not just a metal ruler! ).
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Old 04-17-2010, 04:13 PM   #10
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Quote:
Originally Posted by cre View Post
Chasing threads is a pretty standard practice. You get a tap (thing used to thread holes for bolts) of the same size and pitch of our headbolts and you thread it into the holes (and keep adding oil to lubricate and clear out debris). As you thread it in AND as you thread it out it cuts the metal of the threads back to the right shape and size for the bolts/studs. Not doing this may cause the bolt to reach a given torque level but not provide the actual axial clamping force you want (ie: the shit don't turn so easy so you think it's done too soon).

I really wish they made hollow studs for our cars.... that's the only way to get really close to a given clamping force. Hollow's are great.

Yes, the headbolts are reusable.

80lbs is high... don't go over manufacturer specs just becaust you think it'll be better... you'll break something.

Also, rebuilt of not, you don't know what shape the head was in... could have warped from inappropriate storage. Measure it with a machinist's straight edge (not just a metal ruler! ).
dang. how hard is it to chase threads yourself? and i want to make sure im doing this correctly. also i know the tsrm says 56lb for torque on the head and everyone says its too low. ive seen some do 70lb and then some do 90lb for arp. what do you recommend.

also i think im going to pull the engine out and put it on a stand. so i have a couple questions. how hard is it to drop in a fully assembled engine? would the wire harness be a problem. also i heard that cork oil pan gaskets are no good. whats the best way to seal this? im also going to be double checking all my seals and i think that my rear main seal might be leaking but should be fine.

im hoping that if all goes well i can swap out the tranny during this process.

thanks again guys, let me know if there is anything i should check that could be damaged from the engine.
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