Need 302 help Warner Robins GA

Discussion in 'Technical' started by mrmalina99, Jan 18, 2016.

  1. groberts101

    groberts101 Member

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    Yuck.. I hate those kinds of results! I'd be pulling the left valve cover to physically check valve motion and confirm installed lengths are still all good. Then while you're in there.. confirm the actual firing order requirement based off valve motion. Remote starter switches are perfect for these situations but a screwdriver still works nearly as well.

    Other than being valvetrain related.. I'd guess you either popped a gasket into coolant(obviously not leaking into adjacent cylinder and easy to check by pulling the rad's cap and watching for water in oil).. or you have a cracked compression ring.

    Not real familiar with the Ford EFI stuff.. is the injector driver built into the ECM or is it piggybacked(external)?
     
  2. 71gold

    71gold Frank Cooper Supporting Member

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    stuck valve...:huh:
     
  3. Krazy Comet

    Krazy Comet Tom

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    OK you've nailed it, no compression on #8 aside, the MAP needs at least 16-17" vac to give a decent idle...

    I'll guess it has a performance cam, so vac is low... Of course late timing will reduce vac produced as well...

    Assuming the compression problem is easily fixable, you'll probably need to convert to mass air so it won't be rich and have a decent idle...

    Ford ECM have individual injector drivers inside the unit(not consumer serviceable)... Two if it's a batch fire system or if sequential fire, one for each injector... All Ford 5.0 passenger cars(not trucks), have been SEFI since 1986... Mustang 5.0 got mass air in '89, and '88 in Calif only... HO 5.0 in LSC Lincolns were all speed densety...
     
  4. mrmalina99

    mrmalina99 Member

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    So I found two of these:
    [​IMG]

    I have new ones and now I am just trying to figure out how to properly set valve lash.
     
  5. mrmalina99

    mrmalina99 Member

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    Changed pushrods, set lash and did compression test. I was getting around 150 on all but #8. I got 90 on first test and 0 next 2 tests. Valve appears to be moving normal, could it not be closing all the way or should I be pulling the head?
     
  6. Krazy Comet

    Krazy Comet Tom

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    Oohhh ugly... I'd be looking down through the push rod openings to be sure the lifters are still correctly in place... Likely lifters are pumped up so valves aren't fully closing, let it set overnight and check again tomorrow... If that is case the lifter should bleed off allowing plunger to move into body...

    BTW you do have correct length push rods??? The ones for a roller engine are 6.27", std lifters use 6.80"...

    If engine has bolt down rockers that's exactly what you do, bolt them down... Of course this assumes it has no mechanical problems...
     
  7. mrmalina99

    mrmalina99 Member

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    The pushrods I bought were 6.250. I was trying to set lash and preload.
     
  8. Krazy Comet

    Krazy Comet Tom

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    Close enough...

    All you should have to do is bolt them in place, factory bolt downs are not supposed to need any adjustment(note this assumes the base circle on current and orig cam are same)... The exception is with aftermarket rockers, those usually include shims that can be placed under the fulcrum to decrease preload if necessary...
     
  9. yellow75

    yellow75 MCCI Oregon State Rep Supporting Member

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    I would want to know how the pushrods got bent, did the valves slap the pistons or did the rocker arms get loose enough that the allowed the pushrods to come out of the lifters and come down on the valley wall or did the lifter freeze up and not compress. Always scary when you get bent pushrods at least its just on one cylinder
     
  10. mrmalina99

    mrmalina99 Member

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    I have these:
    [​IMG]

    So I just need to torque the bolts? If so that makes life slightly easier.
     
  11. mrmalina99

    mrmalina99 Member

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    This car sat in previous owners garage untouched for 8 years and was running some really crappy gas. There were two bent pushrods, they were worse than that but I had to straighten it some to even get it out. One was definitely a stuck valve because I had to break it loose.
     
  12. 71gold

    71gold Frank Cooper Supporting Member

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    at the least its time for a valve job...:yup:
    I have a place here in Macon to do it. you have a place in Warner Robbins that I wouldn't let do it...:tsk:
     
  13. Krazy Comet

    Krazy Comet Tom

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    That's it, preload is handled by lifter...

    For the moment don't worry about a valve job, get it running the best you can(80-90lbs is OK to check things out)... You may decide to use a different cam if this one proves not to produce enough vacuum for a good idle...
     
  14. groberts101

    groberts101 Member

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    I find it highly doubtful that a mild'ish cam like yours would cause piston to valve clearance/bent valve issues even if the valve was stood fully open(full cam lift) for 720 degrees. In other words, the piston may not have even contacted the valve head/s so if the valves were stuck in the guide tight enough to pretzel out the pushrods like that?.. then you probably have some bigger issues with those head/s.

    Unless it's a junk motor and you don't mind tossing parts and time at it in hopes that results will suddenly take a turn for the better?(always a time/parts gamble).. I'd pull the heads, go through them and see what needs corrected so it can be done right the first time around. Good luck with it either way you go here and prudently plan for the proverbial snowball effect.. $$$.. that usually follows.
     
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  15. 71gold

    71gold Frank Cooper Supporting Member

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    if the engine was running fine earlier , you have no piston to valve clearance issues...:bouncy:
    PVC would show on all cyls.
    I would go with sticking/stuck open valve....(no compression on that cyl.)
     

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