ZDDP and flathead engines

[Jeff Hansen, #4225]

All,

CLC Past President and Chief Judge Carl Steig has authored an article on a club members recent experience with modern oil in his flathead engine.

The results are worth reading about. The article can be found at this link: http://www.cadillaclasalleclub.org/OldCarsNewOil.pdf TARGET=_blank>http://www.cadillaclasalleclub.org/OldCarsNewOil.pdf

Jeff

[Charles Phelps]

Im going through a similar issue right now in my 1953 Cadillac 331. I had a Hydraulic lifter tapping on start-up, so we replaced. It got quiet, then it started all over again... I dont even have 60 miles on the motor yet. All the lifters were new, as was the cam. The cam is custom though (Isky 262h supercam, mild grind).

This is irritating...and freakin expensive!

Oh, and to add...the engine was rebuilt (everything that could be replaced, was), by a professional engine shop. They even balanced the engine.

Charles

[Randall A. McGrew CLC # 17693]

This is a very interesting, and disturbing, issue.  I have done some extensive research on oils and what should be safe in our older cars.  I now see that I missed the ZDDP reduction which explains the tap I have developed in two of my cars.  My current 56 was rebuilt with the hardened valve seats which I thought was enough.  The only thing I was changing was to go to a basic 30 weight oil.  30W only... now I realize I will have to pay close attention to the ZDDP levels and add that expensive additive to protect the engine.  

Now this covered the Flatheads, not the later OVH engines like the one in the 56.
But if your 53 is experiencing these symptoms, it is a serious consideration.  :-(

[Charles Phelps]

Here is an article that I have been reading. Ive beeen concerned with this prior to the CLC announcement posted above. Unforunately, not early enough.

http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech/index.html TARGET=_blank>http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech/index.html

Charles

[Jeff Hansen, #4225]

Charles,

We have been discussing ZDDP issues since last September.  Do a forum search (link in top right of this window) on ZDDP for more information.

HTH,
Jeff

[Bob Simmons]

As Charles has mentioned, this is not just a problem with the flathead engine, but any engine not using roller lifters.  The Hot Rod article does a good job of spelling it all out.  They have an interesting graphic in there regarding the quantity of ZDDP found in various oil specifications and specific brands.

[Thomas Dodd]

The only thing I was changing was to go to a basic 30 weight oil.  30W only... now I realize I will have to pay close attention to the ZDDP levels and add that expensive additive to protect the engine.  

Id look at the multigrade oils for Diesel engines, like Dello, Rotella, and Delvac. Personally I use Dello 15W40, but Delvac has a 10W30 and some single weight oils too. I am a bit weary of the newest CJ-4 spec, and prefer the CI-4 spec oils.

[baxter culver #17184]

The CJ-4 Delo is also being formulated with a reduction on ZDDP to meet new (2007) standards.  Stick with the API CI-4 for now.  The Hot Rod article linked to this string does have an interesting chart showing a number of different motor oils and their ZDDP additive.

I e-mailed RedLine and was told their product (street synthetics) contain both zinc and phosphorus in sufficient amounts to use in old engines.  The response also said our flathead engines were originally run with oils that didnt have the ZDDP additive in them--it came along later.  That needs to be checked out.  If ZDDP came along after the flathead engine, what was in the 40s oil that prevented wear then??

For now I am sticking with API-SL, SH, SJ oil.  Also use the additives available.  I will switch to Delo or Rotelo once I know what is in the 2007 formula.  I guess the day of buying a quart of 10-30 while on tour is gone.

[Mike Josephic #3877]

According to some info I have, ZDDP did not come into
commercial usage until after WW II -- around 1947.

What was used before that, as an antiwear additive,
I dont know but will do some more research on.  Mike

[Bryson Talamini 21505]

Carl Steig's article panicked me so I phoned Penrite technical, whose oils I have used in my old cars for 25 years, including my 37 LaSalle restored 3 years ago. No they haven't reduced the ZDDP in their range for classics, antiques etc. and their spec range for zinc is 1000-1200 ppm, which they say is plenty. They are available in USA so check out their website address which is Penriteoil. I use the Shelsey Light in the LaSalle because the lifters are quieter than the Medium was, especially at start up. Penrite is what most of the enthusiasts in Australia use, very popular and I have had complete satisfaction fo 25 years
Bryson in Oz.

[Big Fins]

I went to the local Cadillac dealership today to get a set of injector o-rings and the intake manifold grommets for my '77. While I was there I asked if they had any EOS or Cam and Lifter pre-lube. The parts man looked at me and asked why all of a sudden , in the past year they had a run on these two items?   

One of the mechanics was standing next to me at the counter and explained the reason. Then asked me what kind of car I had. I told him and he just sighed and said "Ah, the dream machine."    Well, I did leave them 4 bottles of EOS on the shelf, but wiped out the Pre-Lube. I use a 4oz bottle of the Pre-Lube with a Mobil-1 oil change and cruise.

Fins