rover V8 hydraulic lifters

stag

New Member
#1
I have obtained a partly reconditioned motor. The lifters are new. the valves good. With the motor assembled the motor on T.D.C. No1 , I find I cannot turn the valve pushrods. it would lead me to think that the valves could be partly loaded. In fact I cannot turn any pushrods by hand at this point.
The motor has been running,the manifold and rocker covers are off. Are the rockers meant to have a preload ?
Any assistance or comments would be welcome. I am located in the land of OZ in Sydney.
 

cobraboy

Well-Known Member
#2
Yes.
The rim of lifter cup that the pushrod sits in should be below the circlip in the top of the lifter by between 0.020" - 0.050" when the lifter is on the heel of the cam. This is the lifter pre load setting.
 

harveyp6

Well-Known Member
#4
With the motor assembled the motor on T.D.C. No1 , I find I cannot turn the valve pushrods.
Is it TDC on the firing stroke on number 1, if not the pushrods won't rotate because you are at TDC on the exhaust stroke, not the firing stroke.

The problem with "reconditioned" engines that you have no history with that you don't know what's been done. If the heads have been skimmed, or the block decked, or both, and fitted with tin gaskets, then you could have preload problems, if all that is standard then you won't.
 

stag

New Member
#5
They are preloaded as CB says, but can you not turn any of them?

Richard
With the motor o TDC No. 1 cylinder I cannot turn the inlet or exhaust valve push rod (by fingers) on that cylinder.
I feel that the same will apply to the other cylinders.
 

stag

New Member
#6
Yes.
The rim of lifter cup that the pushrod sits in should be below the circlip in the top of the lifter by between 0.020" - 0.050" when the lifter is on the heel of the cam. This is the lifter pre load setting.
I have measured the gap and it is .050" plus. If it was necessary, how would this gap be obtained?
 

cobraboy

Well-Known Member
#7
The gap can be set by either using shims under the rocker pedestals, or by using adjustable pushrods. It is not uber critical.
 

stag

New Member
#9
I have another problem with my Rover V8 .The motor has been reconditioned . When it has been running for some time, suddenly the right hand bank hydraulic lifters seem to loose pressure & rattle loudly. It would appear the lifters had lost oil pressure. This has happened on 3 occasions.
With the inlet manifold off , I have run the oil pump via priming tool and oil does flow from lifters and holes.
It is as if there was a sudden blockage in the oil pump supply. This happens on the right bank only.
Can any one offer any suggestions ?
 
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#10
The gap can be set by either using shims under the rocker pedestals, or by using adjustable pushrods. It is not uber critical.
I feel that not being able to turn the pushrods by fingers would signify that the valve would possibly be under opening pressure.
What would be the method of adjusting with shims and how much end float, if any, would be desired on the pushrods
 
#11
Yes.
The rim of lifter cup that the pushrod sits in should be below the circlip in the top of the lifter by between 0.020" - 0.050" when the lifter is on the heel of the cam. This is the lifter pre load setting.
I have that gap which is about 0.060" but still cannot turn pushrods by my fingures. Would this indicate the valve is under opening pressure?
If I were to shim the rocker pedestals to take away that opening pressure and be able to turn the pushrods or eliminate any endfloat would
that be a better way to go ?
 

jp928

Well-Known Member
#13
Lowering the gap between the circlip and the lifter piston will reduce the preload. There shouldnt be any preload issues with a std cam and lifters. I would not have thought you would see oil coming out of the lifters - where are you seeing it? Is your oil pressure OK?
 

cobraboy

Well-Known Member
#14
I have that gap which is about 0.060" but still cannot turn pushrods by my fingures. Would this indicate the valve is under opening pressure?
If I were to shim the rocker pedestals to take away that opening pressure and be able to turn the pushrods or eliminate any endfloat would
that be a better way to go ?
If you have @ 0.060" gap then your pre load is correct. You cannot shim to take away pre load, it is designed to be there when using hydraulic lifters. Solid lifters do not have pre load, they have a clearance lash. Standard Rover lifters are hydraulic.

The valve would not be held open, it takes a massive amount of pressure to open a valve, and the lifter would not have bottomed out if the gap is @ 0.060"

I wonder how you can tell that the RH bank is loosing pressure ? If this happens regularly look at the oil pressure gauge and see what is happening when the engine rattles.
It may be you have a general issue with oil pressure due to wear, sticking pressure relief valve, massive amount of sludge in the sump blocking pickup strainer, filter issues.
 

cobraboy

Well-Known Member
#15
I feel that not being able to turn the pushrods by fingers would signify that the valve would possibly be under opening pressure.
What would be the method of adjusting with shims and how much end float, if any, would be desired on the pushrods
NONE, you need pre load.
Do you have the lifter on the heel of the cam when checking ? It is going to be stiff to turn.
 

stag

New Member
#16
Lowering the gap between the circlip and the lifter piston will reduce the preload. There shouldnt be any preload issues with a std cam and lifters. I would not have thought you would see oil coming out of the lifters - where are you seeing it? Is your oil pressure OK?
I have mislead you regarding oil coming from the lifters. it is coming out beside the lifters. Oil pressure is 40 PSI at around 1,000 RPM.
 

stag

New Member
#17
If you have @ 0.060" gap then your pre load is correct. You cannot shim to take away pre load, it is designed to be there when using hydraulic lifters. Solid lifters do not have pre load, they have a clearance lash. Standard Rover lifters are hydraulic.

The valve would not be held open, it takes a massive amount of pressure to open a valve, and the lifter would not have bottomed out if the gap is @ 0.060"

I wonder how you can tell that the RH bank is loosing pressure ? If this happens regularly look at the oil pressure gauge and see what is happening when the engine rattles.
It may be you have a general issue with oil pressure due to wear, sticking pressure relief valve, massive amount of sludge in the sump blocking pickup strainer, filter issues.
After running the motor for around 20 minutes , the tappets rattle badly on all of the RH bank. this has happened on 3 occasions exactly the same.
I am using Penrite running in oil. oil pressure is about 40 PSI at 1000 RPM. It sounds like the lifters on the RH bank have lost pressure.
The LH bank is operating perfectly. The motor is a reconditioned motor all the lifters are new.
On some other sites It has suggested that at that amount of running the oil will be hot and thinner, and that I should put in a standard oil and an additive such as Penrite Lifter & Tappet Fix . Your comments are appreciated
 

cobraboy

Well-Known Member
#18
I missed the bit about the motor being a recon unit :rolleyes:
Well, it is baffling, what you can do is change the oil for a 20-50 high ZDDP product and fit a new filter.
If the engine was assembled with a lot of Graphogen that could have blocked the oil filter and may be causing an issue, but that would be engine wide.
When you say partially reconditioned and fitted with new lifters, did new lifters get fitted to an old camshaft ? if so that is not a good combination.
If cam and lifters were new did you follow the correct break in procedure ?

Check the lower part of the sump is not doped upward due to impact or jacking, this may put the sump too close to the pickup strainer.

#16 Oil coming out beside the lifters does not sound right, they should be a close tolerance fit into the bores in the block, I have not observed a lifter on a running engine, how would you ? obviously they are lubricated and some oil may get by, but how much is too much ?

Surely if the lifters on one bank are bleeding down the motor would misfire, does it ?

I cannot think of a situation where only one side of the engine would suffer from the situation you describe, apart from perhaps an amount of crud or swarf blocking an oil feed to the RH lifter gallery, due to which over time the lifters consume more oil that can be supplied to sustain pressure.

I'm out of ideas now.
 
#19
Penrite running in oil shouldn't be used for more than about 1000kms. Its designed to let the cylinder walls bed in. Is the rattling present at cold or only after warm up? Where are you in Sydney and who did the reco job?
 
#20
I?s there oil coming out of the rocker shafts etc on the right bank when it is rattling The shaft gallery is connected to the lifter gallery only on the right bank with the feed coming from the left lifter gallery. Also it can take ages for the last lifters to quieten up.
I wouldn't be too worried about not being able to turn the pushrods with the engine stopped the lifters are a piston inside a sleeve with a spring under the piston to provide some static pressure when there is no oil pressure. It some cases it can be high enough to make turning the rods difficult, particularly if there is any residual oil pressure (which there will be on lifters in motion). A finger over the spark plug hole compression test will tell you if the valves are seating (if it blows your finger out they're seating - note its finger OVER the whole NOT in it!)
 
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