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Rebuilt engine no compression

Discussion in 'Intermediate CJ-5/6/7/8' started by rsbad454, Aug 1, 2013.

  1. Jan 24, 2014
    rsbad454

    rsbad454 Member

    NorCal
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    These time pretty much the same as a chevy. This isn't a distributor being 180 out issue, this is an actual valve timing event issue. I just need to get back to basics and verify alignment of timing sprockets, damper and TDC.
     
  2. Feb 19, 2015
    rsbad454

    rsbad454 Member

    NorCal
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    Well, I'm just going to pull engine back out and pull timing cover. I have been breaking rocker pedestals and now bent a couple of pushrod. I used the pushrod checker and adjusted it pretty close to zero lash. From what I can see, it isn't too far off.


    [​IMG]
    [​IMG]
     
  3. Feb 21, 2015
    Rick Whitson

    Rick Whitson Detroit Area 2024 Sponsor 2022 Sponsor

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    If it were me I would bring number one to top dead center on the compression stroke, loosen the lifters and pressurize the cylinder see what happens. That would tell you if it were a valve problem or a ring problem. I am no expert, but I think you have to take things out of the problem to figure out what is working and what is not working. Good luck.
     
  4. Feb 21, 2015
    Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    Bending your push-rods or breaking towers is due to the cam trying to open a valve against the top of the piston.
     
  5. Feb 28, 2015
    w3srl

    w3srl All-around swell dude Staff Member

    Port Orange, FL
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    X whatever on the cam timing. If your marks aren't aligned properly on the timing gears you will have all of the above symptoms. First thing I would look at is pulling the timing cover to check that out.
     
  6. Mar 14, 2015
    Chilly

    Chilly Active Member

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    I'm concerned for your valves. You may have flexed the valve head, and eventually it'll fracture and drop the head of the valve.
     
  7. Jun 14, 2015
    rsbad454

    rsbad454 Member

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    Well, pulled engine and found that I screwed up as suspected and installed bottom sprocket on wrong key way, thus not having upper sprocket aligned correctly with the mark I thought I was on. Oops. Combination of working too much OT and rushing to get it running.


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  8. Jul 6, 2015
    rsbad454

    rsbad454 Member

    NorCal
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    Well, I should have the timing correct now...I also had to take each lifter out and drain the oil out. I couldn't preload the lifters because they were hard as rock. If no valves were bent I should hopefully be able to start engine soon.

    [​IMG]


    [​IMG]
     
  9. Jul 6, 2015
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    Ooh, fancy race-car tech ... painted valley. In the past, they'd use Glyptal for that -

    [​IMG]

    more like an insulating varnish; meant for coils, transformers, etc. Said to make the oil drain back to the pan faster.
     
  10. Jul 6, 2015
    rsbad454

    rsbad454 Member

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    I always paint the lifter valleys and typically the rocker area of the heads. Basically fills in the pores and voids in the casting to lessen the amount of oil that stays around.
     
    Last edited: Jul 6, 2015
  11. Jul 7, 2015
    timo2

    timo2 Member

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    Old thread resurrected? How long is this build lol? I do not believe the OHV 304 is zero interference engine. Valves would not contact pistons unless your cam lift and piston dome decided to elope. Crushing valve springs, however-this is likely cause of bent push rods. I admit I did not read all pages re deck height, cam lift, compression. A stock 304 should never have piston strike valve. Ever. Unless the valve keeper failed and it dropped into cylinder at high speed. Even in event of high rev chain failure, I do not believe its possible.

    Of course, I could be wrong. I was once before, when I mistakenly thought I was wrong. ;-)
     
  12. Jul 9, 2015
    rsbad454

    rsbad454 Member

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    [QUOTEresurrection15009]Old thread resurrected? How long is this build lol? I do not believe the OHV 304 is zero interference engine. Valves would not contact pistons unless your cam lift and piston dome decided to elope. Crushing valve springs, however-this is likely cause of bent push rods. I admit I did not read all pages re deck height, cam lift, compression. A stock 304 should never have piston strike valve. Ever. Unless the valve keeper failed and it dropped into cylinder at high speed. Even in event of high rev chain failure, I do not believe its possible.

    Of course, I could be wrong. I was once before, when I mistakenly thought I was wrong. ;-)[/QUOTE]

    Not a resurrected thread, just on going. I wasn't able to get the engine started so Jeep sat for over a year until I had time recently to look at it. This is a stock rebuild with a small 252 comp cam. I made a rookie mistake and lined up the wrong key way with the actual key way lower sprocket was on. I'll find out if valves got tweaked I suppose on start up this time around.
     
  13. Jul 24, 2015
    rsbad454

    rsbad454 Member

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    Got it fired up, wasn't getting oil pressure after a minute or two so. I think I either need to pack pump with vasaline again or pull distributor and run pump with a drill motor.
     
  14. Jul 25, 2015
    Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    I would say either or both is a good idea. Good to hear it fired up tho.
     
  15. Jul 25, 2015
    rsbad454

    rsbad454 Member

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    Yeah, I'll try the lazy way first....and use drill motor. I figured it would have primed from the oil that was still in filter, but I guess not.
     
  16. Jul 27, 2015
    commanlerwrangdo

    commanlerwrangdo Member

    Cleveland, Ohio
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    Yeah, I'd refill the oil filter again and drill-run the oil pump.
     
  17. Jul 27, 2015
    timo2

    timo2 Member

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    Also reduces emissivity, keeping intake cooler. theoretically, and subjective anecdotes...probably has some, perhaps measurable, significance
     
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