Low pressure in cooling system (7mgte)

**kemicalx** · 27-10-2006, 11:19 AM

So this is what i am going to do to start with please point out anything i'm doing wrong,

Set the torque wrench to 54ft/lbs
With a cold engine, and in the TRSM star pattern try and tighten them up some more. (not backing them off first)

Presuming the torque wrench will click off everytime before tightening, i'll then raise it to 60ft/lbs and follow the star pattern again.

Then 65ft/lbs

Then 75ft/lbs

Should i drain the coolant from the system first? as i won't be backing off the bolts at any stage i don't see why it would be nessacary.. Plus i just replaced all the coolant a week ago and don't want to fork out for more

Once this is done, should i warm up the engine again, then let it cool, back off the bolts and re-torque them to 75ft/lbs?

I'm only using the headbolts that are in it at the moment.. as i figure the head gasket leak isn't going to get any worse from tightening them up. If it doesn't fix the problem i'll pickup some ARP's.. then look into taking the head off and how exactly to re-lay o-rings and correctly seal a copper gasket.

**PHOBIA** · 27-10-2006, 11:23 AM

Yep, that sounds like a good start and you don't need to drain the coolant. Good luck.

**kemicalx** · 27-10-2006, 12:51 PM

well that wasn't as simple as i'd liked... my final torque setting was 84ft/lbs and even then there was a couple of bolts that clicked off straight away... really seems like they need to be untorqued just a smidge before re-torquing

**PHOBIA** · 27-10-2006, 01:00 PM

If they where not originally assembled with a friction free thread lube, sometimes you will need to back the bolt of slightly to get it moving.

**EldarO** · 27-10-2006, 04:09 PM

drain your coolant and ditch it.

exhaust gases eat at the glycol and actually make it worse for your engine. so ditch it, and spend $7 on a new bottle.

as for the HG leaking, i cant imagine just retorquing them would fix it... at least not permanantly...

it just seems too easy...

although, give it a whirl, if it works, then all good, if not, ya gotta do it anyway.

i had BHG symptoms up the whazoo, but not all of them.

i had water constantly bubbling out of the overflow, no pressure in the cooling system, and it would heat up quickly (i never let it overheat though).

but...

my car idled PERFECTLY, the coolant was clean and fresh, and so was the oil.

i pulled the head off last week, and it was leaking in 7 or 8 spots, if my sister didnt nick the camera, id take pics and whack em up.

Eldar.O.

**allencr** · 27-10-2006, 10:39 PM

bolts that clicked off straight away... really seems like they need to be untorqued just a smidge before re-torquing

Then it hasn't been 're-torqued' at all!
Back off at least 3/4 turn so you'll get a feel for the threads turning resistance, OK or not, AND to get some lube under the bolt head.
The ones that did seem to torque with you method are either past their prime & stretched, or there was trouble with in the threads or burrs on the washer & bolt head.

**kemicalx** · 28-10-2006, 02:14 AM

thanks for that, thats what i ened up doing for them, they ended up at 85ft/lbs (i'm a little suspect on the accuracy of the torque wrench though). it hasn't appeared to have fixed anything.. i'm thinking i'll have to lift the head and re-lay the o-rings/gasket and clamp it down with some arp studs.