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  • July 27, 2011 11:07 a.m. psychic_mechanic Dork

    I just replaced the head gasket on my 1996 Volvo 960 a couple months ago and everything was going well for several oil changes until a coolant hose blew while I was out of town and the car was run hot. Now it has problems cranking because it's pressuring the coolant overflow bottle, but only during cranking while the engine is mostly warm.

    These are torque to yield fasteners, do you think it would be worth my time to try to give them all another 90 degrees to see if it seals back up? Or I could spend the money on another head gasket or find a motor in a junkyard with less than a quarter of a million miles to swap in. I am a full time engineering student and in between semesters for another couple weeks, so I have tons of time right now.

    I know I definitely shouldn't swap in a T6 hybird turbo engine right now or take the head off just so I can port it, but it's still tempting.

  • AngryCorvair

    July 27, 2011 12:23 p.m. AngryCorvair SuperDork

    i would retorque them and observe in operation. then perhaps dump in a bottle of "Liquid Head Gasket" or whatever the latest super-duper miracle sauce is.

  • mad_machine

    July 27, 2011 1:07 p.m. mad_machine SuperDork

    for the price of a new head.. get your's shaved flat?

  • Travis_K

    July 27, 2011 1:53 p.m. Travis_K SuperDork

    mad_machine wrote:

    for the price of a new head.. get your's shaved flat?

    +1 Just have the head shaved and get a new gasket.

  • Graefin10

    July 27, 2011 2:00 p.m. Graefin10 Reader

    AngryCorvair wrote:

    i would retorque them and observe in operation. then perhaps dump in a bottle of "Liquid Head Gasket" or whatever the latest super-duper miracle sauce is.

    I have done this more than once with success. IIRC the product @ the time was "Bars Leak", but talk to the guys @ the parts store or googel the question and see what comes up. Follow the directions closely. I did it with no antifreeze and then thoroughly drained the block and rad. and left it open for 24 hrs. to harden. Retorque head first of course. Good luck!

  • July 27, 2011 3:18 p.m. Chas_H New Reader

    I think turning the torque to yield bolt further than they have already been turned is a mistake. You risk breaking a bolt, or reducing the clamping force presently applied, or damaging the block.

  • July 27, 2011 3:38 p.m. egnorant Dork

    Sometimes its worth a try! Chevy Cavalier that was an 18 year olds ride to work that was worth maybe $250 running or not.

    One day I saw it ovoiusly overheating and blowing steam out the tailpipe. His plan was to have a friend follow him as he did donuts in a pasture until it blew up and then run away.

    I suggested he tighten the headbolts.. 128 pounds of teenager torque later and it seemed fine. He got another 2 years out of it before he realized he should have changed the oil occasionally.

    Bruce

  • July 27, 2011 10:03 p.m. psychic_mechanic Dork

    Chas_H wrote:

    I think turning the torque to yield bolt further than they have already been turned is a mistake. You risk breaking a bolt, or reducing the clamping force presently applied, or damaging the block.

    Yeah, but I am toying with the idea of swapping in another motor anyway, so I'm only out time if this doesn't work. It may be a good excuse to buy a leak-down tester as well.

  • BoostedBrandon

    July 27, 2011 11:05 p.m. BoostedBrandon Reader

    Get a product called Blue Devil, expensive, but I've had customers say it works great.

  • July 30, 2011 9:23 p.m. psychic_mechanic Dork

    I picked up a HF leakdown tester on sale for $35. On a barely above room temp engine the readings were consistently 60% across all cylinders, or well into the yellow zone of the gauge. After a round of "that feels good" torquing of my TTY headbolts I'm getting 20-25% on all cylinders, which is well in the happy green area on the gauge. I alsp np longer get a pressurized cooling reservoir either. Of course it may still run like crap and mix coolant into the oil, but the results look promising so far.

    Now I'm contemplating redoing the valve seals I should have done when I had the head off, is there a good improvised tool to get the valve retainers off of a Volvo white block, it's pretty tight around the valves? I'm going to drop a length of small rope into the cylinders and rotate the engine around to hold the valves in place, but the retainers look like a pain.

  • Aug. 1, 2011 11:05 a.m. psychic_mechanic Dork

    Half of the valve seals are done. I'll snap a picture of my improvised tool to share with you guys before I button it back up. I'm using a Wal'mart paint can opener to pull the old seals and it works great, has a nice 90 degree bend on the end.

  • nedc

    Aug. 1, 2011 2:16 p.m. nedc New Reader

    As one who has redone a couple of Volvo 960 top ends, I was wondering if you are going to use the pink goo that Volvo sells to seal up the cam cover, or something else? I'm happy and surprised that you didn't snap a head bolt when you retorqued. I've snapped 'em off when removing a head and when torquing down after a head R & R. Don't you love all the groaning and pinging noises those bolts make! LOL I only use new headbolts now when redoing one.

  • Aug. 1, 2011 2:41 p.m. psychic_mechanic Dork

    nedc wrote:

    As one who has redone a couple of Volvo 960 top ends, I was wondering if you are going to use the pink goo that Volvo sells to seal up the cam cover, or something else? I'm happy and surprised that you didn't snap a head bolt when you retorqued. I've snapped 'em off when removing a head and when torquing down after a head R & R. Don't you love all the groaning and pinging noises those bolts make! LOL I only use new headbolts now when redoing one.

    The bolts are new from the head gasket I did a couple months ago, so age may have something to do with it. I got the generic equivalent goo from autozone, used it the first time with good results because IPD was out of the pink stuff when I ordered my parts. It may still leak when running, but it looks promising so far. I want to do a T6 hybrid swap this winter, so I don't want to put a lot of money into this engine right now, if I can keep it running until then I'll be happy.

  • Aug. 3, 2011 3:47 p.m. psychic_mechanic Dork

    The whiteblock is still running well, in fact better than a had for a while. The valve seals fixed my crop dusting problem and the newish lifters make it idle silently.

    Is anyone actually interested in seeing my lever and PVC valve tool? I can post pics if so.

  • nedc

    Aug. 3, 2011 5:57 p.m. nedc New Reader

    Sure, I'd like to see it. No oil leaks either? Good job- gotta love it when a plan acutally works.

 
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