Was just wondering if the synthetics also had a Zinc additive like petrolium based oils? If I switched to a synthetic would I still need an additive to protect the cam and flat lifters? ??? This zinc thing has me worried. My car should be ready to go in about a month and I don't want to mess up the engine.
Quote from: Geoff Newcombe #4719 on May 12, 2007, 03:50:41 PM
Try this for a good read ------ http://www.lnengineering.com/oil.html
Further on down it lists what oils have what but that may change. Safest to put in about 1/2 or so bottle of GM EOS --- unless you are sure the oil you are using has the proper amount of ZDDP. Basically if it is an SM rated oil or CJ4 it is suspect.
Another good read ------ http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech/index.html
I read the above information and found it to be very interesting. Here is a copy of today's email to Redline. Hopefully they will come up with some good advice.
To Redline Customer Service,
I own a low-mileage 1939 Cadillac LaSalle Convertible and the engine has never been run with detergent oil. Many owners of similar cars say that if detergent oil is added, it will dislodge so much gunk that the engine will probably start to smoke and burn oil. This car has the original Cadillac flat head V8 engine with hydraulic lifters. I removed the top valve cover plates and there was a lot of gunk, which I metimeticulouslyoved by hand (not with kerosene or solvent). We then removed the oil pan and cleaned out about 3/4" of thick black mucky oil, so everything visible in the engine is relatively clean now. However, am concerned that if I add detergent oil that the rings will loosen up and create problems that I do not now have - engine runs well, does not smoke or burn oil and is quiet in spite of the gunk that was discovered. I have not yet reinstalled the oil pan, but plan to do so this coming week, when I will want to add the required 7 quarts of the best oil that I can get. You advertise that your oil contains little detergent, so may be just what I need. ???????
Cadillac recommends straight weight non-detergent oil for this motor in grade 20 or 30 for the summer. Also it is necessary that the oil contains zinc and phosphorus to prevent premature wear on the valves, etc. I have been adding a small bottle of EOS with an oil change, but do not feel that my present oil (30 weight non-detergent) from NAPA is the best choice.
My car is quite rare and valuable, so want to use the best possible product. My car did not come with an oil filter and I do not want to add an oil filter, to keep the car original. One of my friends said to use 30 wt. aviation oil and the supplier of this oil said that this was a mineral oil, but did not know of the quantity of zinc or phosphorus.
Any suggestions that you can give me will be greatly appreciated. We are very close to Summit Racing, so I will order the oil from them once I get some technical advice. Thank you very much,
Fred Zwicker
Amsoil has several different viscosity oils that are recommended for our older flat tappet motors. I've been using the TSO 0w-30 and EaO22 filter in my 63 CDV for 5 years with excellent results. I've logged 44 thousand miles on the rebuilt motor, the last 32 thousand with the 0w-30 synthetic. I used Pennzoil 10-30 for the break in period.
Amsoil recommends using proper assembly lube and oil additives during the break in phase of any new or rebuilt motor. After the break in they do not recommend using any additive with their recommended synthetic oil. Not all synthetic oils are equal, be sure the oil manufacturer recommends their oil for our older motors.
Amsoil has a vintage vehicle recommendation chart on their web site that lists cars back into the 50's. You can submit a question to their technical department about your specific car if it isn't listed or if you want more information.
David
An Independent Amsoil Dealer