Save small BHG with retorque?

[StefanLarsson]

Hi all!

I recently bought a MKIII T -91 (I used to own one five years ago (pre family/stationwagon:cry: ) but now I got me one to play with again:biglaugh: ).
It runs fine, no smoke, stable temp, oil looks fine, plugs OK but its loosing coolant and i cant figure out where.
I have to fill the bottle up every other day since it reches the low mark, and I don't drive that much either...

I made a compression test and all of the cylinders came out at 155-160 psi except no. 4 that came out at 130 psi.

OK, BHG... but before I tear the whole thing down why not retorque the head and see what happens to the compression?

What do you guys think? and how much torque should i use on stock gasket and bolts?

/Regards
Stefan Larsson
Sweden

 

[drjonez]

try retorquing them to 70 ft lbs.....i've seen it work.

 

[supramike7m]

i torgued the stock bolts to 80 ft lbs. with a factory head gasket, it held up fine.

 

[drjonez]

stock bolt should NOT be tq'd that high....neither should a stock gasket.

 

[StefanLarsson]

try retorquing them to 70 ft lbs.....i've seen it work.

What's the best way to retorque the head?
- Just tighten them from the center out (TSRM order).
- Cracking them back and then tightening them one by one from the center out.
- Cracking back all the bolts from the ends towards the center (TSRM order) and then tightening them from the center out.

Do I need to drain the coolant to avoid it getting it in the cylinders?

/Regards
Stefan Larsson
Sweden

 

[Boostedstr8six]

I'd (and did at one time) go with option two. However, if you are already losing coolant, a retorque may only slightly extend the life of your HG seal. Which would be helpful and allow you to get ready for a HG replacement while keeping your car on the road.

If you do one bolt at a time you shouldn't have to worry about coolant getting into the cylinders.

 

[malloynx]

a retorque is possible, but if the BHG is slight this is the best time to pull the head. you can pull the head, install a new OEM gasket and have piece of mind.

if you have all the supplies and the head is not warped, this can be done in 1 day.

if the head is looking rough a resurface is in order.

GL, and never reuse oem head bolts

 

[johnathan1]

Damn, a hg job in one day?? I wish I could do it that fast!

 

[swaq]

I agree with malloynx. If a BHG is in progress there is no reason to wait until it is really bad before you actually replace the head gasket. Best to do it before it gets too messy.

 

[Stretch]

BTW yes you can re-use stock hg bolts, they are made of very good metal believe it or not. Unless you overtorque them to 100+ you can safetly re-use them. Many people choose not to however, just so they don't have to worry about it. If you can afford to get ARP bolts or studs, but for a super budget just use the stockers. BTW if the threads are not good them don;'t use them either, look at the bolts and if they check out visually then use them.
eric

 

[trydrew]

BTW yes you can re-use stock hg bolts, they are made of very good metal believe it or not. Unless you overtorque them to 100+ you can safetly re-use them. Many people choose not to however, just so they don't have to worry about it. If you can afford to get ARP bolts or studs, but for a super budget just use the stockers. BTW if the threads are not good them don;'t use them either, look at the bolts and if they check out visually then use them.
eric

That would be a risky bet. I would not re-use the thing that caused the BHG in the first place. If you have a budget so tight that you cant aford new head bolts, you shouldnt own a Supra. Simple as that.

Pull the head while it's not bad, and youll thank yourself later. I did it otherwise and i'm slapping myself for it. Now I have to do much more work then if I would just not been lazy.

Buy ARP bolts at least, and replace the hg.

 

[Stretch]

Failure of the stock bolts does not cause most bhg, but rather the undertorquing of said bolts. The bolts are fine if torqued correctly.
eric

 

[StefanLarsson]

Well, I think I found out where my coolant is dissappering,
I recently added some new hosing (in car bleeder valve) and noticed that they had coolant spray spots on them a few days later.
Nice, I thought, the coolant is spraying out between the block and the top! but as I looked further I saw that the spray was coming from two hose couplings (see picture), I replaced the hoses an installed new clamps and we will se if the coolant stays put...

 

[boost fiend]

i dont trust clamps of that style to hold forever. i try changing mine as soon as i see it seeping a lil bit.