Why are hydraulic roller lifters, different on different sides in the engines?

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Noxnabaker

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Hello folx, new Swedish guy here, & I'm quite confused & sure hope someone can give a seriously good answer...

I just started "stripping for cleaning" 2 -89 318 van engines & they both have different tappets on different sides in the engine!
They're different by the oil-hole on the side & inside there's a ball in one model & a plate in the other but the most confusing I think is that the "big" spring inside at the bottom of the lifters are of different hardness too!!!
& the ball / plate difference makes me wonder if one side gets the oil with higher pressure than the other?

If I wanna swap them for some tune-up brand racing stuff, is all this something worth considering; as in plate / ball + spring-hardness difference?

If they were new, could I put one sort in one engine & ignore the difference?
& what's best: hard-spring ones or softer?
I would imagen harder is better for high-revs but I've been wrong before...

Thanx before-hand & sure hoping for a seriously good & quick answer! ;)
/Nox.
 
& one more thing:
I do NOT need to read that I ought to get other lifters, it's NOT what this thread is about; I just wanna know what I already asked. :)
 
Can't help you on your question but I'd be interested in learning about it as well. BTW welcome to FABO!
 
It seems I can only download "URL" pictures & I've got "JPG" so I reckon there'll be no pics from me.
But there's a thread here called "89 roller-cam LA 360 w/Magnum heads" (or such) by cuda888 here, showing pictures of the lifters showing the difference in the oil-holes.

The most important knowledge thou is why they're different springed & what it would mean to put the same on both sides, pictures or not...

& if it matters what direction the oil-holes points when you or me gonna put it all together again.
 
I find it rather strange that nobody else has overhauled a hydraulic-roller-lifter-equipped small block here in this forum & discovered the same as me & found out the reasons?
But most I wonder why they have different hard springs?
Isn't there anywhere to find out?
I mean that maby there's someone somewhere who's into it at least a wee bit...?
Please... purdy pleeze...?
(I wanna burn some rubber!)
 
342 readers & not one single person knows this?
I reckon it must be the most difficult question in MoPar history!
If it was a cartoon it might've been fun...
 
Hello folx, new Swedish guy here, & I'm quite confused & sure hope someone can give a seriously good answer...

I just started "stripping for cleaning" 2 -89 318 van engines & they both have different tappets on different sides in the engine!
They're different by the oil-hole on the side & inside there's a ball in one model & a plate in the other but the most confusing I think is that the "big" spring inside at the bottom of the lifters are of different hardness too!!!
& the ball / plate difference makes me wonder if one side gets the oil with higher pressure than the other?
That is my first guess.... the pressure is typically higher on the passenger's side than on the driver's side.

Next guess is that Mopar shipped all their worst engines to Scandanavia LOL

How many guesses do I get ?
 
I'd say from the sounds of it that it has different lifters on one side than the other.
Mine were all exactly the same when I did my motor.
 
The part numbers are the same. There is no separate numbers for left and right. You can look them up on Rockauto's website.
 
pushrod oiling seems to dribble. If you got oil shooting as the go-pro showed, you got half of the lifters to replace. Its common for a parts guy to just buy the cheapest rollers especially if he had only 8 to replace, could have got the wrong rollers as cudak888 showed us.
 
Ahhh... here we go! :)
No, you don't have to take them apart.
When I first googled this I found this forum & a guy showing the same thing so I reckon it aint only Euro cars that had it.

SO WHAT ABOUT this then: would it be better to have harder or softer springs in the lifters???

(& post #8: cool pic you have, I always fancied the -62 Darts, had one too, also a Savoy & a Fury of the same year.)
 
I wouldn't think it would matter if the lifter got heavy or light springs, as long as the parts matched that particular lifter body. When the engine is running, the pushrod sits on a head of pressurized oil while the springs are null. The springs just keep a little preload on the pushrod, likely so when you have a cold startup they all don't clatter til you get oil pressure to the upper end and bash the cam lobes. I've seen a couple different roller lifters, but never a different type of lifter in the same engine. If they were all oem lifters in an untouched block, it would mean it was more of a supply issue, where one manufacturer took over the contract and made a slightly different lifter. You received an engine with both types of lifters during the transition. Kinda like my 91' 360, I have a roller cam, but LA style heads. Of course, this was a scheduled thing by mopar. They built the hydraulic cammed small blocks for decades, I'm sure they used lots of different manufacturers. You found a gem or someone else's goofy maintenance.
 
The spring is just there to hold the check ball assembly in place. It sounds like the OP has some lifters with 'check plate' instead of a check ball and the spring is different for that particular internal design. Neither spring should have anything to do with actual hydraulic lifter operation; the oil trapped by the check valve of either design does the work as noted.

I actually don't think the different pressures on one side or the other have anything to do with it... (but there are some strange things done out there). The idea that some lifters were replaced at some time with a different brand makes the most sense.
 
It's easy. Either somebody had a lifter go weak at some point and only replaced the failed units with a different brand/source/production run of lifter...

Or Chrysler had a vendor change and different styles of lifter got mixed in the bin.

There are NO variance in the part numbers in the catalog, and there's no significant difference in oil pressure to either bank, but if lot A comes from Jim Bob lifter company and lot B comes from Chrysler lifter manufacturer facility they're gonna be different. I guarantee that Chrysler does NOT care how they're made, as long as they spec correctly for fit and function.

And that doesn't even include revisionary changes.

This can easily be compounded with an export vehicle where replacement parts could be from a whole different country than anything available here on the US (brisk spark plugs come to mind).
 
And specifically to the op question: remember that it's possible that the motor goes down the production line with a worker on either side, and one person does passenger side and one does driver side. If the supply bin for one side gets filled before the other, you can easily have a half n half situation.
 
Just wondering, how can that be?

If one galley is larger than the other (meaning:heavily restricted), or if there's a significant difference in points of leakage between the two. Otherwise, it will be the same.
 
As I stated in #5, "cuda888" (who I doubt have export engine) had the exactly same thing, even pictures of it, if you just read previous posts...

The small spring that holds the ball or plate have the same strength, it's the bottom bigger spring that's different.

Both engines had the same tapping sound a few seconds when started cold so I reckon one side ( the harder or the softer one?) must be the one to have problems holding pressure...?

What d'ya know: sudenly I CAN show pics!!! :) :) :)
This one is from cuda888's post.

(& anyway, I'm REALLY happy the answers got rolling now!)

Drive-left, Pass-right.jpg
 
Interesting, They both do the same job. They are just different. We may never know why.
 
Just wondering, how can that be?
Look at where/how the oil flows to get to each side:
- Passenger side oil comes straight up the back from the oil filter in a large passage about 7/16" diameter IIRC.
- Driver's side oil has to flow from the far (front) end of the passenger side gallery, which is the lowest pressure point in that gallery, down the small passage (3/16" diameter IIRC) to the #1 main, then across the main bearing area (another possible restriction), and back up another small passage to the front end of the driver's side gallery. And at the #1 main, some oil splits off to the #1 cam bearing, so there is more flow exiting from that area to cause pressure loss. All the driver's side flow has to go a lot farther and through smaller passages; if the lifter flow (through and around) is more, it just gets worse. (Hence the need to pay attention to lifter bore wear and the clearance.)

You can't flow fluid across that path between the front of the passenger side to the driver's side via the small, longish feed passages without some pressure loss. The driver's side is simply further downstream in the system.

I think everyone's ideas exclusive of this difference, are the reasons the OP saw his different lifter designs.
 
So many posts & finally a seriously GOOD answer ! ! !
Took a while to get thou... ;)
 
...but now it makes me wonder what the difference might be when put'n in new tappets of the same model & if there would be a noticeable difference...?
 
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