Re: Flat tappet lifter failure
 

My guess is the change in oil chemistry...

But there is supposed to be remedies for that... (additives)...

So... that begs the question, what is the REAL REASON for the failures?
Self inflicted... (spring pressure)...?
Crappy material/ QC...?
Or some yet unknown quantity...

Inquiring minds would like to know...

Re: Flat tappet lifter failure
 

Well, I am certainly not privy to what the OEs were thinking in the mid 80s, but my guess would be for a fractional improvement in CAFE gas mileage, along with thin piston rings, EFI, low drag, thin engine oils, overdrive transmissions, attention to aerodynamics, serpentine belt arrangements lightweight items , like aluminum blocks and heads, plastic valve covers, intake plenums, aluminum master cylinder and calipers, plastic and aluminum body panels, aluminum radiators and heater cores, smaller displacement engines, cylinder deactivation systems, electric cooling fans, roller rocker arms, aluminum driveshafts, etc.
Hmmm, almost makes you want to built a later model car to enjoy all those benefits, isn`t it!

Re: Flat tappet lifter failure
 

Cummings went to roller lifters in the last few years, and they have had a lot of problems with lifter failure, and i heard its because of the oil, to get away from the high zinc oil.

Re: Flat tappet lifter failure
 

Anybody ever tried using the old GM solid lifter part #5231585?
They are obsolete now, but they have a side orfice with a hardened puck on the face.
Just wondering what kind of spring pressure they would take.

Jim Cimarolli

Re: Flat tappet lifter failure
 

Just FYI, I saw a lifter exactly like the one in the OP, during an online seminar. The diagnosis was EXCESSIVE amounts of ZDDP in the oil. Apparently, people are playing "chemist" with oils, without knowing what they're doing. And, of course, there's always those who think, "if a little is good, more is better, and too much is just right". Doesn't really work with additive packages in motor oil. Once you exceed a certain concentrations, additives such as ZDDP and moly disulfide are no long additives, but rather pollutants and contaminants. They cause damage, fall out of suspension (ever seen a 1/4" plus of gray mud in the bottom of your oil pan?) and clog oil filters.



It should be noted that, over the years, there have been multiple incidences of oil additive packages being incompatible with certain components, a prime example is that several years back, the Joe Gibbs oils were causing a specific DLC coating to fail in the NASCAR Cup series engines. The DLC flaked off in just a few laps.


Never been a huge fan of DLC to begin with, it is a very "picky" thing. It doesn't like certain materials (it cannot be used against cast iron), it doesn't like certain processes, the various versions are NOT all the same, and it doesn't like certain oils or additive packages.


I have not tried it personally, but many are saying "Oil Extreme" is a good additive, used correctly. However, as with anything else, it is NOT going to be compatible with every oil.

Re: Flat tappet lifter failure
 

I’ve also read about issues relating to ring seal if one adds too much zinc to their oil.

Re: Flat tappet lifter failure
 

So...
Does someone make an oil with the proper additives package?
Looking for that "Goldilocks" zone...
Not too much...
Not too little...
But JUuuST RIGHT!

Re: Flat tappet lifter failure
 

I'm sure there are quite a few good choices on the market. Personally, I've had good luck with Driven oil in my engine so far. I used their break-in oil, br-30, and their semisynthetic racing oil, gp-1. Not super pricy, and seems to do a good job.

Re: Flat tappet lifter failure
 

One person you might talk to is Lake Speed Jr. He works at Total Seal, he's a tribologist.


I have had good success with Royal Purple. Others speak highly of Amsoil, which is an oil that David Vizard says works well with Oil Extreme. As Doug said, some have had good luck with the Driven products. I have also used both Lucas and Brad Penn successfully.

Re: Flat tappet lifter failure
 

I have used Renegade race oil 5/20 and 10/30 it only comes in semi-synthetic, I have used it for over 10 years with great results.

Darcy Clarke
6254
A/SA SS/EA