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Technical SBC one valve won't stay adjusted

Discussion in 'The Hokey Ass Message Board' started by Robert Hutchinson, Aug 26, 2019.

  1. I know there has been posts on this before and I've scoured the web for answers but I can't find anyone with this exact type of issue. I'm not any kind of expert, I'm just looking for some help.
    Here's the whole story. I had a sbc 350 4 bolt main motor that had number two cylinder leaking oil onto the plug. Decided to get a rebuilt set of heads (487, new valves, springs, retainers and locks). Thought since I'm doing this, upgraded to an Edelbrock Performance Manifold and 4 barrel carb. Bought new lifters and pushrods. Once I had it all put together I noticed that one of the valves kept ticking after the car had warmed up. Readjusted it and went through this cycle and figured I had a bad lifter. Took it all apart and found I had a cam worn down smooth. So I got new cam, lifters and also put in a new timing chain, sprocket, and new harmonic balancer. Got everything put back together and and the same valve won't hold its adjustment. I made sure I did the proper breakin with assembly lube everywhere and the zinc oil additive for break in with the new cam and lifters. So then I read about nuts backing off and all that so I went and bought a set of 1.5 roller rocker arms with locks. Got them on and adjusted and have the same issue. I can hold the RPM's to about 2000 and the ticking will start, increase RPM's a little and the lifter adjusts and it goes away only to have it come back about ten seconds later. It will do this every time I increase RPM's. Then at idle it knocks when warm.
    The same warn lobe from the old cam, that same valve won't adjust. I've got too much blood sweat and tears into this. I'm at the end. Please, someone point me in the right direction. Thanks
     
  2. The only thing you haven't changed is the lifter bore in the block. Is it excessively worn? That's about all I can think of? For a test. I would just put a new solid lifter on that lobe and adjust to about 18 thousands clearance. see if it changes. It it don't change Heck I would change all the lifters to solid lifters.
     
  3. mike in tucson
    Joined: Aug 11, 2005
    Posts: 485

    mike in tucson
    Member
    from Tucson

    Rocker stud pulling out?
     
  4. GMC BUBBA
    Joined: Jun 15, 2006
    Posts: 3,350

    GMC BUBBA
    Member

    Vote two for the rocker stud pulling out....remove and thread /replace that stud ...
     
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  5. Thanks. I didn't notice anything with lifter bore. Either way it looks like I'm tearing it apart again.
    I'll try the solid lifter suggestion. Stupid question, if it works, can I leave it or do I have to replace all of them?
    Also, wondering about the valve spring. Any thoughts on that being a possibility?
     
  6. No, rocker studs are screw in and didn't appear to be pulling out. I thought that could be it too.
    I can double check the torque spec though.
    Thanks
     
  7. Yes you could continue to drive with just one solid lifter. The only possible cause I can think of is the lifter bore is worn letting oil pressure excape? A weak valve spring would create a miss or a backfire thru the carb.
     
    Boneyard51 likes this.
  8. scrappybunch
    Joined: Nov 16, 2011
    Posts: 285

    scrappybunch
    Member
    from nj

    Fuel pump return spring is ok? Sounds just like a lifter, and in this case its just below #2.
     
    scrap metal 48 likes this.
  9. Thanks. I hope to God it isn't lifter bore.
    The original problem that prompted me to change the heads was on num 2. I'm having issue with #5 now.
    If I changed it to a solid lifter would that fix the bore issue if that is it?

    Didn't have any knocking or issues with the lifters before I changed the heads. More and more I'm going back to stud.
    I'll try the stud first and see if that solves it before I have to take it all apart again.
    Thanks again guys!
     
  10. 2OLD2FAST
    Joined: Feb 3, 2010
    Posts: 1,862

    2OLD2FAST
    Member
    from illinois

    To the best of my knowledge , a solid lifter on a hydraulic cam is destined for early failure. I guessing your tearing up another cam . Intake gaskets are cheap best to look inside ...did you disassemble and wash out the engine after the earlier failures , if not ,you put new parts in an engine contaminated by iron particles , your new parts ,as well as old ones would be very lucky to survive .....
     
  11. Had this happen about 40 years ago on a BBC, it was indeed the lifter bore. Had to have it bushed.
     
  12. There’s just a few reasons a lifter keeps needing adjustment.
    1 rocker stud pulling out
    2 cam lobe change of dimension
    3 lifter length change of dimension
    4. Rocker ball change of dimension

    A noisy lifter that quiets down with increased oil flow (rpm) is different. Perhaps the lifter is defective (happens everyday) or the oil flow to that lifter is inadequate. The bore sloppy or worn or passage plugged.


    We just had a SBC here that had a very persistent valve cover leak over #8. After resealing it 3 times without any relief we ran it without the valves covers on. #8 exhaust valve push rod and only that one had a most impressive geyser shooting a full 1/8” wide stream clear across the fender. I’ve never seen that much oil shoot out that far before. Quite impressive. It’s waiting tear down.

    But we did have a cam go flat on the same engine during break in a few months ago. That lobe was by far the worst one with # 5 being the second worst.
     
    David Gersic likes this.
  13. OK. Just so I understand. The bore was bad so the oil was shooting out through the pushrod over the fender? Did I understand that correctly?
    If so, when I was adjusting the valves, that one did shoot a lot of oil out of it.
     
  14. jersey greaser
    Joined: Feb 21, 2009
    Posts: 145

    jersey greaser
    Member

    are they the cheap mr gasket straight thread style screw ins? '7/16 course bottom and 3/8 fine top" i've worked on a 57 vette 971 heads with the same issue, wound up changing them over to better ones with hex bottoms .
    IMM the ones i took out maybe made in china and softer than the better ones.
     
  15. I haven’t torn it apart yet.
    So I don’t know the exact cause of the problem.
    When cams go flat lifters quit spinning and that lifter bore may be way off or it could be something else. It’s not right what ever the hell it is.
     
  16. I have a lifter (ex #6) in my 301 Chev that has the same issue, i have had the pan off to replace the oil pump and checked the lobe... all good, have checked adjustment...ok. Ran a feeler blade under the rocker...noise went away. My solution for now is live with it.
    As for your motor, i say lifter! JW
     
  17. I didn't rebuild the heads so I don't know what type he used. I don't think he uses cheap stuff. Most of the work he does is for stock car drivers.
     
  18. You can use a solid lifter on a hyd cam. Just use a new one and plenty of cam lube and break it in.
     
  19. Thanks everyone for the advice. Either way intake is coming off and I need to examine the lifter bore and lifter itself. Make sure there isn't any premature wear. Here are some questions I'd like to get your thoughts on before I do this Saturday.

    Anything I can look for specifically in regards to the bore hole? What am I looking for that tells me its a bad lifter bore?
    I'm going to try the solid lifters on that cylinder. I'd have to have 2 solids on the one cylinder right?
    I can't remember if I mentioned that I have roller rockers. Will that make a difference with the solid lifters?
    Will running the solids wear out that lobe quicker?
    Am I losing/gaining any HP if I change all the lifters to solid? (still with hydraulic cam)
    Thanks again
     
  20. Nope solids will not wear out the cam any faster. You could run one solid lifer. The lifter should fit real snug in the bore and noticeable wiggle and its too loose. roller rockers will not care if the lifters are hyd or solids. not enough HP difference to notice.
     
  21. Boneyard51
    Joined: Dec 10, 2017
    Posts: 3,399

    Boneyard51
    Member

    One thing you could try before you tear down the engine, is to change your oil to a higher viscosity and see if it changes the lifter noise. Doesn’t have to eliminate it... just change it.
    That would indicate an oil pressure problem.





    Bones
     
    Old wolf likes this.
  22. Would the pushrods possibly be just a skosh longer or shorter than stock length? Maybe just one pushrod out of spec on the cylinder in question? How does the wear pattern look on the tip of the valves? Has the engine had any serious deck or cylinder head resurfacing?

    My understanding was that you had a better chance of running a hydraulic lifter on a solid cam than the other way around. Solid lifter cams tended to have a slower initial rate of lift in an attempt to make them a little less noisy at cooler operating temperatures, like during a cold start-up. The cam would take up the lash clearance more gently rather than just quickly "slamming" all the lash out of the valvetrain. And with a hydraulic lifter, properly adjusted, there was no valve lash to deal with.

    With a solid lifter things have to be adjusted with some minimal amount of valve lash. A hydraulic cam will tend to have a faster, more aggressive initial rate of lift which makes for more of a shock on a solid lifter when the "lash clearance" is removed before the valve even begins to move. The hydraulic lifter on a hydraulic cam has no need to deal with lash clearances regardless of engine temperature.

    But for your testing purposes I can't imagine there being any harm in temporarily running the engine with one or two solid lifters while you're trying to diagnose things.
     
  23. My guess would be that the solid lifter makes the same kind and same amount of racket on a hydraulic cam as the problematic hydraulic lifter does.

    Let me know if I’m right
     
  24. Quite possibly you are correct. However his problem is the hyd lifter changes its setting. It varies with engine RPM. and no doubt will if continues to run wipe out the cam lobe again. I think he has a lifter bore problem.
     
  25. Atwater Mike
    Joined: May 31, 2002
    Posts: 9,855

    Atwater Mike
    ALLIANCE MEMBER

    "Solid lifters won't wear a hydraulic cam"
    Experience? I doubt it. In '63, had a bud (a serious street racer) named Schwartz.
    Schwartz had discovered a 'speed secret', using a hyd. cam with new solid lifters.
    Racers' discount at Courtesy Chevrolet (San Jose, CA) was a 'perk', but Schwartz's friendship with parts mgr. Maurice got him a 'score'. 20 hyd. cams for under $100.
    Lifters, same deal.
    Schwartz was 'untouchable', for a couple of years. I helped with a couple of 'exchanges', he had a home made quick change timing cover, and some more tricks.
    We changed a cam and lifters in just over an hour...he said he'd done it quicker, and I believed him. Complete flush of crankcase, w/solvent, oil and filter change, etc.
    Life expectancy for the cam before going flat was 20-30 races, or 1 week.
    Seen him do the change on a Thursday, after installing on Sunday.
    I saw the collection, 35+ of them, they stood in the inside wall of his stucco garage.
    Most flattened at rear, I asked him: "Why not get ahold of Isky for a 'safe' solid grind?"
    Schwartz, in his most serious deadpan: "Then everybody'd have it..."
    Solid lifters have a different degree of convex finish, plus the 'shock'. Parkerizing on the hyd. to a solid lobe looked identical, so it was a 'guess' to why they didn't last.
    I was there...many times.
    When Schwartz retired the '55 Chev 210, he bought a '62 Dodge 413.
    He was back in the $$$ street winning.
     
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  26. Very well might be something wrong with the scary alien technology parts within the lifter made by the lowest bidder and assembled by an 8 year old Chinese kid working hard so they don’t harvest his kidneys
     
  27. My middle son Chris when he was 12 built a 289 for his 64 fairlane. Just a ring overhaul bearings & valve job. the cam in his 64 289 was worn . So he pulled the cam from a 75 ford 351 winsor and installed it with a set of brand new solid lifters. When the engine first started we ran it at 3000 RPM for 30 minutes and imediately changed the oil and filter. Used 20w50 Valvoline racing oil. And that little engine will turn 8500 RPM. and we still have it. cam still good after 30 years.
     
    26 T Ford RPU likes this.
  28. My guess is that since he wasn't "class" racing where he might have had to contend with the occasional tech tear-down, Schwartz was using these hydraulic cams with solid lifters as a poor man's "cheater" rate-of-lift camshaft and treating them as a maintenance item. Kind of a Bic Disposable Cam & Lifters. Though it seems like a lot of extra trouble for unsanctioned street racing. :rolleyes:
     
    Atwater Mike likes this.
  29. Tried pushrods from another cylinder that was working fine and did the same thing.
     
    Old wolf likes this.
  30. What would you recommend?
    Should there be an oil pressure change once the engine is warm?
     
    Boneyard51 likes this.

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