Think Oil Is Oil? Well Butter My Butt And Call Me Toast.
OK, confession time. For the past month I have been on pins and needles and depressed about oil. The new W was burning through a quart of oil every hour of running at around 2300 RPM. Now. I blamed myself. Was there something I did wrong while breaking it in, did fuel get into the oil and cause the cylinders to polish? Was there a broken ring. Hey, stuff happens. Now. I had not had any issues or even noticed the oil pressure before. It was all fine. Ran perfectly, But man oh man-o-shevitz, a Qt an hour and burning like a pig. The smell was horrible. SO.. What was it. I built up the courage to call Dave Van Ness and admit my failure to take care of his engine. I had changed the oil like a good boy, to 30 wt Non Detergent oil from Napa, the only stuff available here in non detergent. The owner manual says to do that. Everyone says to do that. Except the engine plate says 40 wt! mmmm Are “W”s says it, the “H” says 40 wt.
All Oils are not alike. When I said I used Napa to Dave, he said. “Oh.. Use Rotilla 30 or 40 wgt.” Rotilla is a Shell product designed for Diesel Engines BTW. But also is used on older engines. Yup, read around. The older car guys swear on it, not at it.
And so, we did just that we changed the oil. I couldn’t wait. My nerves were at the end, and how could a simple change of oil brand make such a difference. To be honest, even Dave was curious. Sure it might make a little difference. But 1 qt an hour is a dramatic amount.
Well Slap My Ass and Call Me Shirley. NO SMELL, NO BURN, I am Shocked. SHOCKED I tell ya. I don’t know why, or the chemistry behind it all. But its like the day we started it this spring. With the Rotilla that Dave put in it in the first place. Night and Day, Black and White, it could not be more dramatic.
So if you are having excessive blow back. ( A cooked oil smell in the cockpit ) maybe, just maybe its the brand of oil. Try this before you spend a fortune on more dramatic things. A Huge thanks to Dave, again, and again for sharing some of his wisdom on the matter.
Now back to sexy shots of oil cans. Cause no one wants to look at Napa plastic bottles.
I run Brad Penn!
Also a great oil for these boats. One key is to make sure you have ZDDP in whatever oil you are using.
I use Brad Penn 30W in my 1958 Century Resorter 16 as well. Easy to order online and allows the dodgey old Dearbomatic transmission (which uses engine oil) to shift with some reliability.
With a flat tappet cam, in addition to brand and weight, detergent or not, you also should make sure the ZDDP levels are sufficient or use an additive.
I recommend people talk oil with their engine builder because rebuilt engines are not the same as they were when new, and oils are very different than 20 years ago, let alone 60 or 80. What the factory recommended in 1948 is not likely to be the best choice today.
What is ZDDP?
I have tried to keep the collecting down but I couldn’t pass this item up. It even has the old oil!
I wasn’t that familiar with Rotella. You should go to https://en.wikipedia.org/wiki/Shell_Rotella_T for an explanation and competitor brand names.
ZDDP means that the oil contains zinc which is needed to lubricate the flat tappets in older engines. I use Vavoline VR1 20 50 racing oil which seems to be one of the best choices of those oils that contain zinc.
Does Rotella contain ZDDP?
All motor oil has some zinc, it matters how much. Ted Cartner built a MBL for me recently and said to shoot for 1000ppm of zinc. He recommended Valvoline motorcycle oil, designed for wet clutch applications. It’s inexpensive and available at most auto parts stores.
I was once told that racing oils are designed to free up horsepower, not make engines last long. Racing engines are usually torn down after every race or two. Not sure how true this is, just food for thought.
These are in my office, the good one is in the shop waiting for me to get the boat done.
Yup it’s good stuff!
I always use one quart of Lucas heavy duty oil stabilizer in my 1954 chevy… had the same problem with blowby when the engine had backpressure on downhill grades… the Lucas oil additive buttoned it up!
Here is a GREAT thread on The Buzz about oils, ZDDP, and such.
ZDDP = zinc dialkyldithiophosphate or something like that. It is a oil additive that greatly reduces wear in metal on metal contact points particularly when there is significant pressure involved. In older engines this is most pronounced with flat tappet cams.
Modern car engines have lover pressure on the lifters and use roller cams so there is less need for ZDDP. ZDDP kills catalytic converters and is not all that environmentally friendly, so there has been a push to greatly reduce the amounts in modern engine oils.
If using a standard modern oil that does not have enough ZDDP you can use an additive to bring the levels back up. There also some specialty oils that still have the proper amounts, and even some that have too much. You want to find out how much your oil has (WITH EACH BATCH YOU BUY) and dose any additives to get the correct amount as too much or too little can both cause wear issues. Be careful because formulations can and do change and won’t likely be spelled out on the front or even back label. A brand you buy today may not be the same as it was 2 years ago and may not be the same 2 years from now even though the packaging looks identical.
By the way, it is most critical in newly rebuilt engines.
Another vote for Brad Penn for President! Do I have to tell you Amazon has it?
Use genuine Wood Boat Oil.
Just for inboards.
The best oil out there to use is Brad Penn. Most of the Brad Penn formula’s are the old Kendall oils before the Kendall name was sold off in the early 90’s. Most everybody called it the green oil. Its still green today and made in the old Kendall refinery. Up until the name was sold and production stopped. It was the recommend oil for all the european manufacturers. Porsche, Audi, Alfa Romeo, Ferrari, etc. Also ask any SCCA racer from back in the day. All they used was Kendal GT-1.
Chris Craft went to 30 weight in 1955 for all engines. If your engine has been rebuilt and the trans cleaned out use a detergent oil in it. What you don’t want is a detergent oil in an engine that has a massive amount of sludge built up in it. Which is what you will get if you run non detergent oil.
Also running a multi weight oil in an engine with no thermostat is pointless. It will stay the lower of the 2 numbers. So if its 10w40 then it will stay a 10 weight oil.
We almost exclusively used Shell Rotella SAE 30 when I worked at the Antique Boat Center. I still use it today in my 30′ Lyman in the 270 Crusaders and have never had an issue. It is good stuff and easily available.