NoEmissions84TA

iTrader: (1)

Continued from here: https://www.thirdgen.org/forums/tech...ml#post6282053
This applies to hydraulic ROLLER lifters also.

NoEmissions84TA

iTrader: (1)

Here is my engine test stand setup. Notice the cutout valve cover and the white lines painted on the pushrods to make sure they rotate.
If the PRs rotate, then the lifter is rotating. Flat tappets MUST rotate - you absolutely do not want this to happen with a roller cam & lifters.
Oil would show at the rocker arms only above 2300 1400 rpm. Below that, nothing.





Okay, so let's open these lifters up and find out what is really going on.



Looks the same to me..............
Or does it?

Continued tomorrow.

GeneralDisorder

iTrader: (1)

Well - I know just what I'm doing with the set of those that I bought. Good thing I thought better of using them and put in some Comp lifters. $hit I hope those are alright.

Also - some of those pictures in the other thread (they showed up) are very interesting - so the timing chain gets a lot of oil from the parting lines on the front main. Are you saying that adding additional chain oiling holes may be somewhat superfluous due to this observation? I'm always leery of redesigning a system that currently works.... sure the chains stretch, and the stock sprockets wear but it wasn't *that* bad after 160k on my LB9 - even with a nylon sprocket. I don't see additional oil having that much of a positive effect being that they already last about 100k in stock form with poor quality 1980's oils. With today's synthetics I can't see this being a significant problem. I didn't modify my chain oiling in any way on my Vortec build. And seeing those images I am happy I didn't put any more holes in my lube system. That's just going to lower (minimally, but still...) the oil pressure at idle.

GD

OrangeBird

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It looks like the oil hole is smaller in the Delphi VS the real GM ?

NoEmissions84TA

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GD, what is coming up next will show you if those SKIP WHITE lifters are any good or not. They ARE made offshore, and the machining actually looks to be excellent. They can claim "Made in USA" if their headquarters is located in the US, even though the parts are made offshore.
But none of that matters if they were made wrong. What I will show should be checked on EVERY lifter, because after "The Great Lifter Shortage" when 2 of the 4 manufacturers went out of business and the 2 left couldn't supply the demand, these offshore lifters flooded our market. Unscrupulous people were buying good GM lifters and the knockoffs, then putting the knockoffs in the GM boxes and returning them for a refund. To this day there is no guarantee that the good box of lifters you purchase actually has the correct good lifters in it.

With what I have observed with the diesel fuel test, additional oiling is not needed for the timing chain/gears. You drew the correct conclusion. I, myself drill a tiny (like .030") hole in the face of the block into the center main oil gallery to supply a little oil so that the back of the cam gear cannot gall into the block. Look at the back of the gear and you will see 4 relief spots to let that oil drip out. Also a little oil drips out of the front cam bearing to lube the chain, as the posted GM diagram shows. And you are correct, today's oils are better.
If you install screw in plugs, on some blocks you have to be careful that the center plug does not go in too deeply, because you can cut off the oil flow to the front main bearing. I avoid this by half moon notching the plug that gets installed there.

NoEmissions84TA

iTrader: (1)

I never actually measured the inlet holes, but that was not the problem.
I'm typing up the solution now. Stay tuned...........

NoEmissions84TA

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Okay, let's not keep everyone in suspense.
It is the thickness of the pushrod cup/seat that is the problem. The .058" thicker cup in the JUNK Delphi renders the pumping mechanism inside the lifter inoperable. It would be exactly the same as adjusting your rockers down all the way until just before cracking the valve off it's seat (on base circle). You have removed all of the preload and and if you were able to run the engine this way, there would be no oil coming out of the pushrods to lubricate the rocker arms (and cool the valve spring).

Tootie Pang

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That was AWESOME. I need a cigarette. Well done NE84TA.

GeneralDisorder

iTrader: (1)

Now I have to measure my Comp lifters. And those Skip White lifters that are still in the bag. Couldn't bring myself to use them.... all mine are hydraulic roller units so it will be interesting to see if this is true of them also. I do have the original GM Vortec lifters sitting around also. I will measure and photograph and post up my findings.

GD

NoEmissions84TA

iTrader: (1)

Please do.
I feel bad for the Corvair guys. Replacement lifters for their engines are non-existent.
They must recondition used lifters (special grinding procedure for the bases) or use the closest match - which happens to be a Chevy lifter.
So a bunch of those guys had the same problem of no oil to the rockers at idle. Some tried to modify the lifter internally to get more oil flow, and others went so far as to fabricate external spray bar systems to spray oil on the rockers.
http://corvaircenter.com/phorum/read...,673214,page=1

GeneralDisorder

iTrader: (1)

So here's data from the Skip White hydraulic roller lifters:



And here is the stock Vortec hydraulic roller lifter - definitely original to my 97 Vortec block:



I haven't measured my Comp lifters yet. Try to do that soon.

GD

NoEmissions84TA

iTrader: (1)

Did you get those pictures backwards, because mine show the opposite?
But mine were flat tappets and yours are rollers - both hydraulic.
Maybe the PR seats between tappets and rollers are different thicknesses? Could the manufacturer have mixed them up?
Anyways, at least we now have something concrete to look for.

Let me add this info from Grumpy's:

BTW EVER WONDER WHY WHEN YOU PRELOAD THE LIFTER MORE THAN ABOUT A 1/4 TURN ON THE ROCKER ADJUSTMENT NUT THE VOLUME OF OIL SQUIRTING OUT OF THE PUSH RODS DROPS OFF RAPIDLY?

That's really simple, the seat in a hydraulic lifter rides on a cushion of pressurized oil, oil that's displaced up the push-rods as the cam lobe sweeps under the lifter base, as the lifter returns to the cam lobes base circle the lifters seat is pushed back up to full height by oil pressure (one reason lifters tend to click with low oil pressure).
The potential problem is that the total distance the seat supporting the pushrod moves is usually about .055", a full turn on a rocker nut is usually .040, so the more you preload the lifter the lower the volume of oil under the lifter seat.
BTW roller lifters are very similar just with a roller wheel added to the base.

GeneralDisorder

iTrader: (1)

No they aren't backwards. You can see in the pictures how the Skip White part is shiny and new. The old Vortec lifter is discolored and has some staining from the milkshake in that engine. Indeed it is odd the numbers are reversed. I will try to take the lifters farther apart and see what the dimensions of the rest of the components indicates.

GD

Tuned Performance

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GeneralDisorder

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Here's the comp pushrod seat:




I measured everything out, and it ends up working out that ALL the other components are the exact same dimensions between stock Vortec, Skip White, and Comp. What is different is the seat itself and the difference is the stock seat is .065" taller (above the lifter piston only). With a 24 TPI rocker arm stud you will need to put an additional 1.5 turns of pre-load on both the Comp and Skip white lifters to put them in the same position as zero load would be on the Vortec lifter. So it would likely be that you need 1.75 to 2 turns to get them in the correct position compared to a stock lifter with respect to pushrod length, and setting the piston in the same position for pumping oil. Either that or your reduce your pushrod length and go with less pre-load I guess? It's all a bit confusing really. I'm not quite sure which way (if either way) would result in more/less oil fed to the rockers.

Perhaps this was done to facilitate back yard mechanics that crank down the pre-load past 1/4 -1/2 turn thinking tighter is better? Definitely gives you more of an acceptable strike zone. I'm not sure what the idea behind this is but I would think along those lines....

And I guess that leads into.... how much pre-load did you put on the Skip White hydraulic flat-tappet lifters with the larger pushrod seat? Because it looks to me like they are one of the type that wants very little. Like 1/4 turn maybe.

Also - now I see why the conventional wisdom for cam break in is to run the engine at 2500 rpm. It's to pump lots of oil up there for proper lubrication as they are lapping in. Also seems exceptionally important to not only fill the engine with oil but also ensure that the heads and valley are pre-filled so the oil feed to the pushrods doesn't have to catch up with all that empty space.

GD

NoEmissions84TA

iTrader: (1)

GD
Regarding the PR seats, I think you are forgetting that the retaining clip is in the same location on both sets. Therefore the thicker seat is positioned deeper into the lifter body by that difference - (299 - 241 = .058"), which happens to be same as the depth of the space available for the pump inside the lifter body. So if an incorrect thicker seat got installed into a lifter made for the 241 seat, then the "pump" would be rendered inoperable.

BTW EVER WONDER WHY WHEN YOU PRELOAD THE LIFTER MORE THAN ABOUT A 1/4 TURN ON THE ROCKER ADJUSTMENT NUT THE VOLUME OF OIL SQUIRTING OUT OF THE PUSH RODS DROPS OFF RAPIDLY?

That's really simple, the seat in a hydraulic lifter rides on a cushion of pressurized oil, oil that's displaced up the push-rods as the cam lobe sweeps under the lifter base, as the lifter returns to the cam lobes base circle the lifters seat is pushed back up to full height by oil pressure (one reason lifters tend to click with low oil pressure).
The potential problem is that the total distance the seat supporting the pushrod moves is usually about .055", a full turn on a rocker nut is usually .040, so the more you preload the lifter the lower the volume of oil under the lifter seat.
BTW roller lifters are very similar just with a roller wheel added to the base.

I set my SKIP WHITE lifters originally at 1/4 turn after clearance removed. No oil below 1400 rpm and less than there should have been above that.

GeneralDisorder

iTrader: (1)

Something isn't adding up though - all the dimensions of the lifters, including the depth of the bore, are the same on both of my sample lifters, yet in my case the thicker PR seat is from the factory lifter which was clearly adequate - this Vortec lived 177k miles with virtually no wear on anything so the lifters were definitely pumping. When you say the lifter was "made for" the thinner seat the assumption is that somehow, in some other dimension, it is physically different - like the bore depth is shallower?

What is the bore depth on your SW lifters and was it different than the GM model?

GD

NoEmissions84TA

iTrader: (1)

I have a couple of pics, I can take more if needed.
My combination engine stand & test run stand was given to me. It was home built from 1/4" wall 2" pipe. 4 legs and very heavy.
Also given to me at the same time was a SBC engine that was supposed to be a 350.
It was actually a poorly rebuilt 267 (bad connecting rod reconditioning - cone shaped big ends) with all the freeze plugs rattling around inside the block and a few other things wrong, but the funninest thing was the 800 cfm thermoquad carb on it. I was working at an automotive machine shop at the time, so I took care of correcting the issues. Since a 267 and 350 both have the same stroke (3.480"), there was no way I could tell which crank was in there. Because the 267 pistons are so much smaller than a 350 (3.5" vs 4.0"), they are lighter and if the crank was wrong, then there would certainly be balance problems. I was not going to go through the time and expense of balancing a 267. So I wanted a way to run the engine before installing it in any vehicle. I planned on putting it in my 80 Monza - would have been a great daily driver, but it got rear ended.
So I modified my engine stand to run the engine on it. I added braces/legs to the motor mounts, put a piece of plywood on the bottom for a battery, added an electric fuel pump, garden hoses and the necessary adapters for water in & out, MSD ignition system, made a control panel with switches and gauges, and made a set of headers to work with the stand. The 267 was re-rebuilt with the equivalent of an Edelbrock Performer package. It runs great and is still sitting in the basement collecting dust 25 years later. It is really nice to have a test stand because you are able to do the break in, check for leaks and problems, and get the engine dialed in before putting it in a vehicle. Plus it's a lotta fun too. Or I can run it with open headers if there are any neighbors I want to **** off. Or, months of troubleshooting improperly made hydraulic lifters.

Water IN.


Water OUT.


You can see headers, battery, motor mount leg.


Pre lubing.


Control panel.

Tuned Performance

iTrader: (92)

3rdgenmaro

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Just goes back to the thread I started a year ago. Which lifters can you trust? I still haven't bought any, but the time is coming. Hard to spend $240 on a set of true Johnson Hylift, but durn Id hate to eat a motor for trying to save another $100.

NoEmissions84TA

iTrader: (1)

I can double check, but I am 99% sure they were the same in every way - except for the pushrod seat thickness.

NoEmissions84TA

iTrader: (1)

xxx

NoEmissions84TA

iTrader: (1)

After all of this and spending more money AGAIN to get this engine running again, I bought ISKY. No problems.

3rdgenmaro

iTrader: (9)

That's what I'm looking at right now. ISKY Anti-pump up 202-HY.

NoEmissions84TA

iTrader: (1)

That is what I bought!

ISKY Quiet Power 202HY Anti-Pump-Up
Hydraulic flat tappet Superlifters (2 oil holes)
Manufactured by Johnson/HyLift/Topline

3rdgenmaro

iTrader: (9)

Sounds like I'm on the right track! Thanks!