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Update on my engine problem

Discussion in '1969-1972 K5 Blazer | Truck | Suburban' started by Yukon Jack, Jun 15, 2005.

  1. Yukon Jack

    Yukon Jack 1/2 ton status

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    My engine with a fresh cam, lifters, springs and rocker arms bent a pushrod and broke numerous teflon valve seals. When I went to try to pull the valve springs I could not get the cylinders to hold pressure so I was told I needed to pull the heads to see if I had bent valves. I got the passenger side head off last night and just got back from a machine shop with good news and information on what happened.

    To start off, I was told the valve springs needed to be shimmed up as presently they were at about 70 lbs when closed and the cam specs required 90 lbs. The machinist said he would actually like to see a little higher than 90 lbs.

    The whole problem surrounds the teflon valve seals. When the problem occurred a number of people pointed their fingers at them and they were 100% correct. I reviewed alot of information when buying all the components and I sure thought I read that those valve seals could be used without machining but I was obviously wrong on that I now learn.

    When the spring compressed the valve seal was not seated properly resulting in contact strong enough to bend 1 pushrod and destroy numerous valve seals.

    While the heads are off the machinist will do a valve job even though he said they were not too bad - the heads are off so now is the time to do that and start fresh.

    He will also machine the studs to accept the proper valve seals and then he will have the heads prepped for reinstall with new guideplates that I have that will be used in connection with 3/8" pushrods.

    The total price for the head work will be in the neighborhood of $240 which sounds awfully fair to me.

    Now I have to figure out how in the world I can put the heads back on without messing up the new head gaskets. It was a bear getting the head lifted off and I don't know how I will set the heads back on the installed engine without screwing up the head gaskets. Maybe I can install some all-thread rods to use as guides so the heads drop down cleanly.

    Then I need to figure out how I am going to get the torque wrench on a couple bolts at the back of the heads. Clearance is minimal and as it is now a torque wrench will not get back there. Probably gonna have to lift the cab up one side at a time to gain enough clearance - oh the joy :doah:

    Definitely a relief to know what caused the problem and that it's not going to be too expensive to fix. The extra time that will be involved sucks but oh well, what else do I have to do in the late evenings :doah: :surepal: :screwy:

    As a side note he said I should stay with the peanut port heads as I am after low end torque with this very heavy truck (about 6,000 lbs) - really didn't want to finance different heads so that is good.
     
  2. Burt4x4

    Burt4x4 3/4 ton status

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    Thanks for the update YJ.
    Sounds like your back on track...just a lil more time and money ;)
    Best of luck to ya and let us know how it goes :D
    Burt
     
  3. tarussell

    tarussell 1/2 ton status

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    Glad to hear that you found what was wrong !
    Tom
     
  4. Ryan B.

    Ryan B. 3/4 ton status GMOTM Winner

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    sweet. glad to hear its nothing too serious. and the price to fix it is not bad at all. Sounds like more work for you than anything..
    70 or 90 lbs eh? I'm putting a 260/260 @ .050" .587" lift Crower custom grind solid roller cam in my BBC, it takes 212 lbs of seat pressure. :crazy: :cool1:
     
  5. 3 on the tree

    3 on the tree 1/2 ton status

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    How much more would he charge to install screw in rocker studs??? Money well spent.
     
  6. Ryan B.

    Ryan B. 3/4 ton status GMOTM Winner

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    I thought big blocks are screw in rocker studs?
    small blocks have the press in ones on factory heads? :crazy: :confused:
     
  7. Yukon Jack

    Yukon Jack 1/2 ton status

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    These heads do have the screw in rocker studs. I'm letting him replace the stock guides for new Comp Cams guides for the new Comp Cams 3/8" pushrods. Amazing how much beefier they are than the stock 5/16" pushrods.

    Got the other head pulled last night. It was a bear to get one of the rear bolts out. Going to be very difficult to get a torque wrench back there. My 3/8" Craftsman ratchet fit with a little room and I had to use a section of my floor jack handle slipped over the ratchet to help break the bolt loose. Better not tell Sears I did that. Like I said above, unless I can find a very thin torque wrench, I am afraid I will have to raise the body to have enough clearance to torque that bolt and maybe one or two on the otherside.
     
  8. 3 on the tree

    3 on the tree 1/2 ton status

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    Seems to me like Snap On sells an adaptor just for that, wouldn't hurt to ask.
     
  9. 3 on the tree

    3 on the tree 1/2 ton status

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    I just read the part of your post about setting the heads back on w/o messing up the head gasket. How bout using some of the old pushrods, taping them crossways across the top of the block, and then seting the heads on them and kinda sliding the heads in place???
     
  10. zeroz400

    zeroz400 1/2 ton status

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    You might be able to jack up the rear of the trans, would be easier then moving the body.


    Later
     
  11. Yukon Jack

    Yukon Jack 1/2 ton status

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    Ryan B. - looks like a healthy cam you have. I looked at my cam spec card and it says Closed 90 Lbs @ 1.875 or 1 7/8, Open: Open 249 Lbs @ 1.395 but my cam is pretty mild - it is the Crane Energizer 266.

    A buddy measured his 3/8" torque wrench with the correct socket and it is just a little thicker than my regular ratchet so I might just get lucky and be able to torque those rear bolts. Gonna be close. Better have Burt do some more good karma dances when it is time to put the heads back on.

    As for taping some push rods to the block surface, that just might be a real good way to do it. It's all gonna work out just gonna have to be real careful and have a little luck on my side.

    Heads should be done sometime late next week. Then will have to find a buddy with some free time to come over and give me a hand.
     
  12. Burt4x4

    Burt4x4 3/4 ton status

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    Hahaha I got your back Bro!
    Later today when all my co-workers are in I'll bust out a Positive Karma Jig in cubical, it doesn't work as well if you don't have 10 people stairing at you thinking "what the hell is Burt doing"...I just tell them it's a flashback from the 80s hahahahaa
     

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