Hydraulic roller cam valvetrain woes

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sydcuda

sydcuda

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Hello All,

Been a member here for many years but it's been a long time since I posted. I have a stroked '89 360 roller cam engine which was rebuilt by an engine builder who is now interstate from me (I've moved). I've had nothing but problems with the engine so far - it's been installed and run just a few times. I had massive valve train clatter to begin with and worked out that there was inadequate push rod clearance with the Edelbrock heads. So I pulled the heads and clearanced the push rod holes. I also went back to stock 1.5 ratio rockers and that problem was solved. Heads back on and engine buttoned up, but STILL unacceptable valve train clatter. I played around with different pre-load adjustments and managed to quieten things down a bit, but still not enough. Some of the lifters were not pumping up. I read somewhere, in relation to Magnum roller cam engines at least, that the lifters have to be installed a certain way, ie. with the bleed holes FACING UP. So I've now pulled the intake and found that all of the lifters were installed with the bleed holes FACING DOWN. Yet most still pumped up. I took one of the 'bad' lifters out and took it apart. They are new lifters and everything seemed fine. No dirt or debris preventing the check-ball from closing etc. I tried to 'pump' the lifter up on the bench by immersing it in oil and pushing the plunger up and down many times, but no pump-up. I'm not sure it is even possible to bench pump a lifter in this way - perhaps they pump up properly only when in the engine and under oil pressure. Anyway, to cut what is becoming a long story short, my questions are:

1. Do the lifters in an LA roller cam block have to be installed with the oil bleed hole facing UP, the same as in Magnum roller engines? This seems counter-intuitive to me as the oil galleys in the lifter bores are on the lower side and would line up with the oil bleed hole in the lifter if it is installed DOWN.

2. If the answer to (1) is yes and the lifters were installed wrong, can I expect the 'bad' lifters to pump up with them installed correctly or are there other things I should be looking for as well?

Although I have no confidence in the engine builder (given his mistakes) I'm hoping this will solve my valve train noise and be the last of the problems encountered, so I can begin to drive and enjoy my '68 Barracuda FB after 14 long years.

Any help greatly appreciated! Cheers
 
The correct position for the oil holes is toward the center of the block. The reason is so they will not bleed down when the engine is cut off. If they are installed toward the outside of the engine, they are on the downhill side and the oil will follow gravity and leak out causing lifter noise on startup. They will fail over time from starting dry if they are not repositioned. The orientation of the holes in the lifters to the holes in the oil galleries is a moot point, since the lifter has an oil groove. It will get oil regardless.
 
Thanks, that makes sense in terms of bleed down. But I'm wondering why some of the lifters, even installed wrong/down, didn't pump up in the first place?
 
sydcuda said:
Thanks, that makes sense in terms of bleed down. But I'm wondering why some of the lifters, even installed wrong/down, didn't pump up in the first place?
Click to expand...

Because they are installed wrong and have bled completely down. Lifters are not supposed to bleed down. Sometimes they cannot recover.
 
I've tried multiple preloads from 1/2 turn (.020) to 2 turns (.080). The greater preload quietened down the lifters that were actually pumping up, but the lifters that wouldn't pump up of course remained noisy.

I think I'll just buy a new set of lifters, the ones I had were DNJ (Domestic and Japanese) probably crap.
 
I would run the oil pump with a drill and oil pump priming rod. With intake off run oil pump with drill while slowly rotating engine. Make sure no oil hemraging between lifter and lifer bores is ocurring.
 
I will ask, how is oil pressure? Make sure the oil gallery plug on drivers side near dist. is in and tight. It plugs the lifter gallery oil . seems like a no brainer but I forgot it and this is not my first rodeo.!! Thank god you can put it in without removing the engine. Will make lots of valve train noise.
 
Hughes engines sells roller lifters that keep the oil hole lower on the lifter due to Ma Mopar chamfering the lifter bores lower on some blocks. Look at Hughes engines website and the have a great illustration of what I'm talking about when you look at their lifters. Part # is HUG5321. They are working great in my 410 stroker.
 
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