Hey All,

I found two lifters that would not pump up. Disassembly verified check valve in lifter is culprit.

I order 2 of the "new light weight VW Lifter" assuming it is a suitable single replacement. They are a lot stiffer.
I don't have to replace all of them do I?

Thanks

 

Call Roger. He stocks them.

 

Most customers change them all. The difference in weight may have an effect.

 

Anyone else ever just change out a few lifters with the new type?

 

There's no reason why two new won't work with 30 old. The question really is, will 30 old keep up with 2 new? In my experience, all the lifters in the same engine experience pretty much the same conditions and duty. When you see two fail, is it a fluke or is it the tip of an iceberg?

Were it mine, they would all be replaced.

 

Thanks Doc

 

That seems like good logic, although lifter failure at 100,000 miles is really rare (I'd be trying to figure out why the two lifters are bad....is it a problem I created by "messing" with them, or are the legitimately just bad?)

One other thing to think about is that a good set of 928 camshafts are getting harder and harder to find....and thus more and more expensive.
Not sure what Porsche has in inventory for S4's but they don't have a complete set of either GT cams or GTS cams. And the cams they do have are ~$1500 ea.
I'm using DLC lifters (not just nitrated, but actual DLC) in most of the engines I do, which still have good camshafts. (So, not the VW nitrated lifters, which need to be modified to work.)
The "extra" investment ($50 each) makes sense to me, especially if the vehicle is something that the client plans on keeping.

 

There's a back story to the VW (designed for use in VW, but sold to wholesale accounts, from INA) lifters. When I used to take them apart and send them off to be DLC treated, about 10% would be rejected, before the DLC process got beyond the polishing phase (True DLC coating requires the surface to be very, very smooth....almost polished.) The lifters, which got rejected, had "hot spots" created when the lifters were made, by the grinding process. ("Hot spots" are actually "heat treated" spots, which are "harder" than the surrounding material. This is HELL on camshafts.) INA then put a coating on the face of the lifters, which "hid" the hot spots. The DLC people considered the lifters with the "hot spots" to be junk and not appropriate to run through the DLC process (I agree.) The problem was, they would never call and tell me the problem....they would just send me back 25-30 completed lifters. I finally got smart and started sending them 40 lifters to make sure I got back at least 32.

In the end, "cheap" and "good" are not words that automatically go together in the same sentence. While "cheap" and "good" sometimes can be used together, it is pretty darn rare, and requires some "self defensive" thinking and checking. In this case, INA was "cranking out" the lifters to keep the costs down (something probably forced on them to do) and was too aggressive on the grinding of the lifters (machine time is actual money to any parts manufacturer.) This resulted in the "hot spots.

Certainly not always, but sometimes, you get what you pay for.....really true with these lifters.

 

Thanks All,

Love it when I learn new stuff that I can use.

During my last refresh, I learned a little about the lifters and how to clean them up a bit.

This time I went a step further and totally disassembled them, to include the tiny check valve (spring and steel ball). soaked in brake cleaner, and ultra sonic cleaning 3 times each.I ruined one of them when I cracked the ball seat during re assembly. So thinking I was good to go with replacing with a single VW lifter. I oiled them all up and stashed away until I was ready to install. Last week during installation I got a syringe and re-oiled them, and double checked the check valve function after being placed in the head with the weep hole facing up. That's when I discovered the additional old one that was not pumping up as well. After dissection I noticed a small variance on the check valve seat. I am assuming this was the cause of the slight pressure differentiation.

I have my old TBF engine that I will pull lifters out and go through the process of Disassembly and cleaning. All the while understanding that there will be some metal contamination that has migrated from the block/thrust face. into the old lifter. in general. the cleaning solution was clean after the second ultrasonic run. I expect that I will double the process to try and get some piece of mind.
I may try to just use the valve seat and the original body.
Not the ideal process, but it is what it is.

 

Great plan. Just install the internal pieces from your TBF donors into your clean lifters....that way the same lifter will be riding on the same cam lobe (I assume/hope you kept all of them individually separated....)
Getting the "debris" off of the internal "ledge" in one of these lifters is an incredibly difficult process...ultrasonics will not generally get this done! The "debris" on the internal ledge of the lifter turns into a thick grey "sludge", much like what is found in the "sludge traps" (oil drillings) in the crankshaft.

 

Great plan. Just install the internal pieces from your TBF donors into your clean lifters....that way the same lifter will be riding on the same cam lobe (I assume/hope you kept all of them individually separated....)
Getting the "debris" off of the internal "ledge" in one of these lifters is an incredibly difficult process...ultrasonics will not generally get this done! The "debris" on the internal ledge of the lifter turns into a thick grey "sludge", much like what is found in the "sludge traps" (oil drillings) in the crankshaft.