Eric D

The forum has had a lot of discussions on hydraulic lifters. Which LS series lifter is best to use seem to be a common theme. To this I thought having a look inside the two most common lifters might shed some light on this subject.

The fine print. Ok, before I venture any farther let me point out that any information here are my thoughts and in no way have anything to do with the companies mention here in.

First off, there are two main suppliers of hydraulic lifters for factory built LS series engines, Delphi and Eaton. If you were to order a crate engine or order a new Corvette, or any GM small block engine the lifters in it could be from ether company. Is one brand better then another? I'm sure you could get arguments ether way. In my opinion, both are very good produces and are the best in the world at what they do.

I'm going to start this thread off simple, with some pictures showing a Delphi and a Eaton lifter. If there is an interest in learning more on hydraulic lifters I can add more as we go. I invite your participation on this subject and if you have some interesting photos associated with lifters, cams, pushrods, rockers, valves, springs, retainers, and keeper that have something to do with the hydraulic lifter, please jump in.


In the above photo you can see the Delphi lifter on the left with the smooth looking undercut areas. On the right, the Eaton. Notice the undercut areas look rougher and also note the oil inlet holes are at different locations.



The above photo shows Delphi on the left and Eaton on the right. This is the roller that rides on the cam lobe.



One more view of the roller. Note the needle bearings can be seen on the Delphi roller in the above photo.



Top view where the pushrod ball is seated. Again, Delphi on the left, Eaton on the right. Note that the Delphi clip is gold in color. This is one way to tell one brand from the other.



What's inside? Well, this photo shows the part that make up the workings of the Delphi lifter.



This is the inside workings of the Eaton lifter.

I posted the chart below in a different posting but to keep things together and make it easier for someone else to find I'm adding it here. This chart shows the preload for the different part number lifters that can be found in LS engines.



LINK - What Causes a Noisy Lifter

LINK - Schematic How a Hyd Lifter Works

LINK - Proper Hydraulic Lifter Preload

Blown427conv

Any pics of the roller wheel and bearings dissassembled?

Eric D

Really not much to see. The axle shaft goes through the main body of the lifter and also is the inner race for the needle bearings. The roller ID is the outer race for the needles. I believe there are 16 needles.

ZeeOSix

Looks like there is alot of difference in the design of the guts of the two brands. Just from a finish viewpoint, it seems the Delphi is better ... but the difference in the guts design is interesting. Are those photos showing all the internal parts on both brands?

Eric D

The only other parts that are there, but hard to see, the high pressure chamber check ball and spring. They set under a steel top-hat piece that houses the ball and spring.



The above photo shows the top-hat that houses a small spring and check ball.

Blown427conv

I'd like a hybrid Delphi with the Eaton polished roller wheel. Since there are no pics of the axle or roller bearings, I'll just take the Delphi version of those on my hybrid please.

SteveDoten

where did you get the pics and info? cool stuff

chuckster

Nice Job Eric! I think I have a bad lifter from a mechanical overrev.. What scares me.. is that the ticking has gotten quieter.. Common sense tells me things dont repair themselves..

Eric D

Chuckster,

Lifters are quite durable and can withstand more then what most people would think. I have no real way of knowing if this would hold true in your case, but I have seen where the high pressure check ball and spring goes into resonates and will allow the oil in the high pressure chamber to leak out past the check ball. This will normally never happen with the exception of exceedingly high acceleration levels like in an over rev situation. If this is what happen in your case, it would cause the lifter to collapse and it would start ticking due to the excess lash. However, it would return to normal function after a short time of running. Common sense or not, they could have appeared to have repair themselves.

Thanks for your comments!

itzza427

Interesting,,thanks for doing this layout! Hope I never have to get that far into it,,but will keep this in mind if I ever have to!!

ajg1915

Nice post.

mazak

not that it matters but we just started doing work for eaton where i work

Eric D

Does the work have something to do with lifters? I would be interest and hear about it if it doesn't put you in an awkward position with your company.

dgrant3830

Very good post on them. I wore out one or two of them on my LS1 some years ago but it wasn't till 274K miles when I took down the top end. I don't remember which lifters it had in it and I no longer have them. The indications started with the usual tapping when cold at startup. It would last a few seconds and over time, the tapping took longer and longer. It took so long that engine temperature would have to start rising in the IPC on the analog guage. Finally, it suddenly got real bad with loud tapping. Replaced all of them of course, along with rods, rockers, springs, seals and etc... no more tapping.

chevylad

Do you know the weights of the lifters or are they real close?

Eric D

Delphi, the current replacement unit, part number 17122490 weighs 123g. I'm not sure on the Eaton unit but will see if I can find out.

mazak

no we do make a part that looks like that but it is a aerospace part

Bill Curlee

Very cool post!!

voda1

Eric, care to comment on this: http://www.ls1tech.com/forums/12067177-post31.html

Eric D

Not really. All that need be done is to have the part number for the LS7 and the LS1 pulled up and see what the difference is, they are one in the same. The numbers in the table above are right from the prints. If someone wishes to believe someone else, that is their choice. Why do you ask? Are you having a problem with your lifters? If that is the case I would be glad to help out.