from day one, I could never get my valves to stop clattering. adjusted cold, ever rocker ticks. adjusted hot and running, I adjust 3/4 turns past and by the time I finish the last one, the first few are clattering again! I just replaced all the lifters and again, adjusted cold is far from correct. it would barely run! as I adjusted hot, it smoothed out. ran 20 minutes and rechecked, they all needed readjusted! I have screw in studs and locking adjusters that have remained tight, getting oil threw pushrods. finally got it right, drove a mile and it started knocking. despite having new lifters, it acts as if their not pumping up. I can depress them easily. I have adjusted valves on hundreds of motors over the years and never had this issue before, what am I missing?
when hot, 10 lbs at idle and 35 @2500 rpm's. I did not use I high pressure pump as I was told it would cause issues on the inline 6's. I was concerned that might be too low but engine builder insisted it was plenty. oil dribbles out the rockers but does not squirt like other engines have. engine rebuilt 3 years ago and doubt it has 20k on it. oil pressure same as when installed, I believe/hope the knock is from valves out of adjustment but haven't ruled anything out!
Why did you change lifters with only 20K on the engine? What did the old lifter faces look like?
I couldn't adjust them as they seemed to bleed down too easily. been chasing a slight miss since new. at about 1 1/2 or 2 turns past zero lash, it smoothed out and vacuum held steady. while it ran very well, I was concerned they would pump up at higher rpm's. several easily compressed with just my thumb pushing on rocker. new ones are the same! I reset all at 3/4 turn and removed side covers to verify 0 lash. every rocker ticks and has the same slight miss, adding a full turn, it idles perfect and no ticks. the oil barely trickles out top of rockers and 10 lbs at idle, I would swap the pump if it might help but really tired of blindly throwing time and money at it.
Most people don't tear down and blueprint them, they just take them out of the box and stick them on. Never assume they are good to go or correctly spec'd without verifying. All of them we used needed to be tweaked from the gears being too deep in the pump body to the surface where the cover plate bolts on being a source of a pressure leak.
Might not be a bad idea to cut your oil filter open and check it out too as a precaution.
the originals cam with the Clifford cam, the replacements are sealed power. is there a better lifter I should use? would more oil pressure help? I can get the pump out be removing cross member and pan but not sure what I would check once it is out.
That's not enough oil pressure to suit me personally. The valve spring pressure is easily overwhelming the lifters ability to allow satisfactory adjustment at only 10 psi. Blueprinting the oil pump could help, but in the end, your bearing clearances have a lot to do with how much pressure the oil pump can sustain.
"the gears being too deep in the pump body to the surface where the cover plate bolts on being a source of a pressure leak"
Yes, examine this, should have no more than .0025" end play between the top of the gears (pump upside-down) and the inner face of the cover, with a used gasket of known quality (not a piece of paper).
If it's significantly more than this (over .003") you need to remove depth from the body casting. If you have a steady hand you can lap the end on an old mirror with valve grind compound (I make "figure 8"s). Surgically clean after!
Do not tighten the cover screws to more than 9 ft./lbs.
If, as said, it's loose bearings increasing the idle speed even 100 RPM may bring the pressure up. Otherwise I would try increasing the oil viscosity slightly. Not straight 40!
That was also our procedure for prepping the pumps. Make sure you debur the gears on the face where they mesh into each other as well as the top and bottom side where they meet the pump body and the pump cover plate. Once you disassemble yours, you will see evidence of scarring on the gear plate where the teeth were not deburred originally from the factory, and over time this can become a problem. You can also sand the cover plate in a figure 8 pattern to remove any scratches that may be in it. I've seen the end play on many pumps regardless of brand name be .008" to .010", so don't be shocked if yours is in that range.
I suffer from a disorder in which I am compelled to radius & blend any drilled, cast or bored opening into the port or passage on either side. The first rule of hydraulic engineering is "reduce pumping loss on the LP (low pressure, suction) side", which is where the pipe leading from the pick-up head transfers incoming oil to the gears.
Trust me: you will intuitively understand what I mean when you examine the parts. A 1/8" carbide bit in a Dremel will do this in a few minutes, finished with a fine abrasive bit or even a fine file and hand sanding.
You'll feel better!
Clifford says springs have 115 lbs. seat pressure. seriously doubt I am loosing pressure at the bearings, it was low from the day it was rebuilt and hasn't dropped any more. should I start with a new pump? what brand? I do remember the builder commenting on the brand pump I had. I can handle removing material to spec. and deburring but would rather start with a better product, if this a difference in brands.
You will have to disassemble and blueprint any pump you buy, so check out the one you are running so you can eliminate or confirm it as a possible cause of the problem. At only 10 psi your valve spring pressure is collapsing the lifters. You should have enough oil pressure at idle that it sprays the underside of the hood, not just barely trickle out of the pushrods. You absolutely will loose oil pressure through the bearings if the bearing clearance is too much. You will loose pressure even if you have too much clearance on a cam journal or if the lifters have too much clearance in the lifter bores.
Lots of good advice. I'll add it's well known there's a lot of junk pumps on the market last few years. I always blueprint the original or build my own. If you've got a non orig pump the bypass provision may be poor.I've seen oil pickup screens too close to sump bottom. May not be your problem but something to consider. Been professional 65 yrs and remember the 50-53 235 low pressure hydraulic lifter engs idled at 3 lbs.hot oil perfectly OK. Let it idle for a while and she'd start ticking. Lifter bores couldn't have much more than '001" or it'd be a common trait. Many hydr lifter engs I do like '30s V12 Packards and V16 Caddys, etc run 5lbs idle. That's factory spec. Pumps are linear also usually too big in the first place. A lot of people use the rule of thumb on full pressure engs of 10 lbs per 1000 RPM. Not a bad place to start for most engs here. JME David
More rambling from on old geezer: Seems bizarre that you can collapse the lifters just pushing down on pushrods.I've seen oil pickups get a little air sucked into pump. Usually if bad enough the pump won't prime immediately when starting. But still shows good pressure as you noted. Had a couple guys install new pump and later discover the pump cover screws were loose and getting looser. Just cause something's new doesn't mean a thing. I'll presume you're reading OP along lifter galley. Make a small clear plastic line connected to that point . Let it drain into rocker cover area. See if air bubbles continue. Wondered if your cam & lifter combo places the lifter oil groove in the block's galley fully enough for sufficient feed volume, Those pushrods usually squirt quite a bit requiring the little clip on "umbrella" tools saving a big mess while adjusting running. Don't know your usage of the engine, but 115 seat seems high. What's open pressure? Verified during installation? David
haven't tore it apart yet, but will check the pump. lifters gave me concern and easy enough to swap but fixed nothing, still seams odd they are so soft. had small blocks idle at 5 lbs. and lifters never clattered but had stock springs. don't have the tools to test the spring pressure, they came with the cam (206/526). hoping to get to it this week.
had a few hors today so I isolated the knock to the torque converter hitting front of transmission. flywheel bolts worked loose so had to pull the tranny to tighten them! needed a shim between crank and flywheel anyways so fixed the excessive play at trans. and starter doesnt grind anymore! while I haven't even touched the oil pump or valves yet, at least I know its not a rod! enough for today.