Rocker shims = NO rocker shaft oiling

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With the shims in, was it blowing oil out the sides of the rocker stand?
I'd think the holes in the shim are at least the diameter or larger than the shaft oil feed hole.

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After taking out the shims and slowly spinning the crank which I wasn't doing incrementally while spinning the pump it finally started spraying/ flowing coincedenly and I assumed it was the shims. I thought the hole was not big big enough to allow the oil to get thru and came up with the notching plan. One post mentioned in doing so would allow the oil to be miss directed away from the shaft in stead of towards it. I checked that theory this morning and found that with that one shim missing...he was correct. Later today when time allows, I'll put the shims back in and be more patient with the priming to see if it will work.
 
I didn't modify the shims and put it back together and the oil seems to be flowing good.
Thanks for the suggestions
 
Yea, I built my first 340 YEARS ago and was priming it with no oil to the rockers.
Started turning the crank and it sprayed oil to the ceiling!
Sometimes its the simple things that bit you in the rear!
 
Anti pump up lifters [ APUL ]. Properly designed APUL do NOT use a paper clip circlip, which is what stock lifters have. They use a much stronger circlip to stop the lifter pumping apart due to pump up.
The minimum pre-load idea came from hot rodders & there is a very good chance that the engine could come to grief. Russian Roulette with a 6 bullet revolver & 7 bullets....
As I said earlier in this thread:
- using strong enough valve springs prevents pump up.
- you have about 0.150" of lifter plunger travel. There is no need to set the pre-load so tight for the reasons stated above.
 
Bewy said:
Anti pump up lifters [ APUL ]. Properly designed APUL do NOT use a paper clip circlip, which is what stock lifters have. They use a much stronger circlip to stop the lifter pumping apart due to pump up.
The minimum pre-load idea came from hot rodders & there is a very good chance that the engine could come to grief. Russian Roulette with a 6 bullet revolver & 7 bullets....
As I said earlier in this thread:
- using strong enough valve springs prevents pump up.
- you have about 0.150" of lifter plunger travel. There is no need to set the pre-load so tight for the reasons stated above.
Click to expand...

Agree with mosta stuff, I've read a few times 0.090 is the max adjustment travel.
Never checked it, cuz I'm one of the guys running at the top of travel, I don't think I've ever gone more than 1.5 turns on a stud, I usually stop the noise, add 1/2 to one turn, that's it.
When Isky brought out the anti-pumpup, it had a second hole thru the side for bleed off, later it was an internal mod to have the bleed inside . iirc
The thing about cranking down adjustment to near bottom, - that's how far the cam lobe can wear before noise, - at the top, wear off a coupla thou, and there's noise to go looking for trouble before serious damage, jmo.
 
Last edited:
Inertia,
Yeah I remember the Isky Anti Pump ups. The reason for so much internal lifter travel is to allow for production tolerances....& maintenance. Heads being milled during an overhaul &/or valves being sunk with a valve job.
You certainly wouldn't want to bottom the lifters out completely, but on an all iron engine you could certainly go to within 0.010" of bottomed out & still have internal clearance. Even if the clearance went solid, it is not going to wipe the lifters/lobes because all that would happen is the valves are held slightly of their seats; probably cause some rough running because the valves are not seating.
 
Bewy said:
Anti pump up lifters [ APUL ]. Properly designed APUL do NOT use a paper clip circlip, which is what stock lifters have. They use a much stronger circlip to stop the lifter pumping apart due to pump up.
The minimum pre-load idea came from hot rodders & there is a very good chance that the engine could come to grief. Russian Roulette with a 6 bullet revolver & 7 bullets....
As I said earlier in this thread:
- using strong enough valve springs prevents pump up.
- you have about 0.150" of lifter plunger travel. There is no need to set the pre-load so tight for the reasons stated above.
Click to expand...
Every,..EVERY engine w/hydraulics I have ever assembled where I was setting preload, I set to .020-.025". I have NEVER had a single tappet or cam failure, ever. Only one cam, a 292°MP SB cam, lost a lobe after 15yrs. of street/strip use, a 6bbl mill that had seen routine shift points of 6,900-7200rpm in trying 4.10,4.30,4.56:1 gears out back.
No spring "prevents" pump up, it minimizes it, and the tendancy is directly a function of valve/retainer/spring mass, ramp rates, & oil feed/pressure.
 
Killer6,
If you set your pre-load to 020-025 & never popped a pushrod cup or circlip, it means........your springs were strong enough to contain 020-025 of pump up.
The rest I agree with.....
Cam manufacturers recommend springs that are strong enough to prevent lifter pump up for the upper rpm range of THAT cam for two reasons:
- pump up, even a small amount, causes a power loss because the valve is held open
- because pump up can knock out the p/rod cup, bend prods etc.
 
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