bhg, after bhg?

[bobpogoman]

ok guyes sorry for my bad language, im french but ill do my best to explain.

i bought a supra with a 15000km engine rebuilted with arp studs and cometic hg. the car had a bhd on it so i took off the block//head from the car and got it machined to a shop that knows the 7m well.i also bought a 2.0 hks mhg stopper and used the used arp studs with the rest of moly lube.

took everything together then my friend torqued my head studs for me @ 85 lbs. the car was o.k. at idle, but when i was rolling a little it smoke a lot white and some white smoke come out of the hg outside the engine. took back the car in the garage then, un-torqued all studs and noticed that one was at around 50 lbs of torque.re-torqued everything in 4 passes (40 70 90 95) lbs of torque and re-assembled everything.

result: the car is doing the same thing, what could it be :S?

 

[IJ.]

You shouldn't relax the studs for a retorque.....

The idea is to do one stud at a time in sequence, undo it until it just "cracks" releasing the 80 ft/lbs torque then pull it straight back to 80 and move onto the next.

 

[suprahero]

Is it blowing white smoke out of the exhaust?

 

[bobpogoman]

yeah white smoke from exhaust AND from the block/head


and IJ, you mean just removing like 10 lbs from the studs (just a very little but of un-torquing) and then going to 80?

but why it would change something if i simply un-torque everything and re-torque everything? im not doing a re-torque like after the 5 heat cycle, im just re-doing everything myself to be sure its well done.

 

[suprahero]

All you do is break it loose and then retorque it..........one at a time.

You bought a new cometic headgasket or reused the old one?

 

[IJ.]

It's been running so yes.

When you undid all the studs I'm guessing coolant/oil has found it's way onto the mating surfaces and contaminated the Viton sealer.

If one of the studs was only at 50 ft/lbs I'm also willing to suggest that the head is now warped after being run so there's little chance of it ever sealing.

With the 7M you pretty well get 1 (one) chance to get it right at a time.

 

[bobpogoman]

i bought a hkg 2.0 stopper mhg,

and IJ, ull find this idiot but my friend torqued it firstly with a 3/8 drive torque wrench wich is in in-lbs instead of ft-lbs and when he completed it i added coolant, and it was leaking out of engine, so yes the viton thing is contamined with prestone, i didnt thought it could hurt the gasket :S

so what do you suggest me? remove the head, clean it (with what?) and for the hg? dont you want me to remove the viton thing and use a sealer?

 

[IJ.]

Damn that sort of sucks!

If you pull the head now you'll have to totally strip the Viton using paint thinner.

Check the head for straightness/flatness using a machinists straight edge and feeler gauges.

Wash the head and Deck surfaces with thinner.

Seperate the main layers and spray with light coats of VHT Copper Spray, then carefully using the Head studs as guides lower 1 layer onto the deck lining it up on the dowel pins.

Repeat for the next 2 layers one at a time (you only get 1 go at this so take care)

Once they're all down slide the head on and run the sequence to 30 ft/lbs

repeat at 50 then again at 80 (taking time in between to hit your bud with the torque wrench)

Draw out the headbolt sequence from the TRSM and tick each stud off as you tighten it it's that critical.

 

[bobpogoman]

viton got a color? and there is some on each layer? or on the layer going to block and the one to the head?

for the vht copper spray, what the can looks like got a picture?

and what you mean by putting layers on the dock surface one by one? theres rivets holding the layers together..?

 

[IJ.]

Viton is Grey

You have to remove all the rivets and strip ALL the Viton

 

[bobpogoman]

ouch god damnit :S how can i remove the rivets without hurting the gasker,? i dont remember how the rivets where made on the hg.

 

[HommerSimpson]

Rivet hitting ? new hks i got i had to get rid of one of the rivets up front i think it was...left front of engine...

 

[IJ.]

I use a small pair of wire cutters and squash the end of the rivet then pull it out the other side.

It works perfectly and doesn't mark the gasket at all.

It all needs to be clean enough to eat off before you start spraying.

DON'T let the layers touch before they're on the studs as they WILL stick instantly to each other and if they're not aligned pulling them apart means back to step 1.

 

[bobpogoman]

ok thanks guyes, so i just lost my supra for another 2 weeks :S my friend better dont come to my house for these 2 weeks, or he will have a 3/8 torque wrench mark in his face

lets see if its hard to remove this head with the engine in car :S

 

[IJ.]

Be very careful lifting it out as it's really easy to hurt your back.
(unscrewing the studs will make it 1000x easier)

 

[bobpogoman]

ya thats what i was going to do, since its not easy but we will be 2 so there wont be any problem. thanks IJ

 

[IJ.]

Not the same helper with the toy torque wrench I hope

 

[bobpogoman]

ok guyes just an update like that, i just tried the car agin, when its 100% cold, it dont smoke, but after like 20 sec of driving (getting a little hot) its start smoking BLUE when i accelerate. i didnt saw any white smoke from exhaust, only blue.

weird?

and theres also whitish smoke coming from under the manifold,but, a lot of oil has been here (at least 3 liters on the engine, then on ground :S) the 4liters of oil accidently slipped off my hands, maybe thats causing the white smoke? and i may not have head gasket problem?

and just a notice like that, the machine shop machined the block and head,changed the rings,main and rod bearings and homed the cylinders.
they also checked if the head//block was cracked but they were o.k.

and here are the mods i installed since the engine has been to machine shop:
wideband o2 sensor+gauge
Oil catch can
dual stage boost controller
safc neo
hks fcd
hks 2.0 mhg stopper

 

[IJ.]

Do all of the usual tests to confirm the head has sealed ie Leakdown, Comp test, Napa Combustion Coolant test.

 

[bobpogoman]

im actually removing turbo and manifold, to see if theres really coolant getting off the engine, if its not the oil i put on the engine.

after ill do a compression test, but if the machine shop job havnt been made well? the compression will be shown bad for bhg or nething else wrongly did.

napa combustion thing is around 50$ its my last option, dont think ill do it since it may be maching shop fault, or my fault, both way ill have to remove the engine or head.

what is the leakdown test?

and ehm with a BHG did the car can smoke blue?