Do you guys really think that the engineers and chemists at the oil companies that are trained and hired because of their expertise in things like this are not keenly aware of all of this? The trend to trivialize proven science and technology seems to be running rampant these days.
I like science. My independent testing of a 302 we built in high school (around 87 or 88)proves it. Still on the road today. Tons of miles. Has ran every kind of oil around. Diesel stuff, walmart brand, the odd ball oil from the gas station, lawnmower oil, some stuff out of a drum we had growing up, recycled oil, just about everything from straight 30 to 20/50 and in between (This testing was mainly due to youthful ignorance and shallow pockets) still going Oil is good. We should use it (My OT stuff gets whatever is recommended though)
Shhhhhh!! Don't use rational thinking on a forum that is dedicated to irrational thinking [eg old jalopies in a modern world]
The reason that diesel oil isn't good for gasoline engines is because of the different additive packages. Essentially, the soot dispersants required in diesel oil react negatively with some of the additives required by gas engines and render them ineffective. Here's a video I found on a Corvette site that explains why in detail. If anyone can watch it and fully comprehend it, they will switch back from diesel oil tomorrow.
Explain to me the animation at 1:45.... Also, the summary at the end of the video is specifically calling out differences in injectors between MODERN gas and diesel engines. I didn't catch or hear them mention any significant study of lubricating performance of diesel oil in an engine built 70yrs ago, or built today using 70yr old parts....
First, the animation at 1:45 is simply a demonstration of how a diesel engine combusts the fuel mixture. I would think that would be pretty basic; I'm surprised you had to ask. As to your second point, 70 year old gas engines have a LOT more in common with modern injected gas engines than they would ever have with any diesel. Also, different "API Ratings" of automotive engine oil (the "SP/SQ" emblem he pointed out) are currently available; this is the "Old Car" oil mentioned earlier in this thread. Hell, you can still buy non-detergent oil if you really want to mess your engine up. Third, this is about the differences between additive packages and the associated degradation, not basic lubrication.
Another video from the same content provider that created the first video. Why do only his engines blow up from using diesel oil in gas engines?
Of course, it's not common. They are just showing what can happen when all of the wrong factors add up. That being said, I will freely admit that running diesel oil will make no perceptible difference in almost all cases. However, after all is said and done, it is worse to use diesel oil in a spark ignition engine, not an upgrade, so why do it? Refer to my post #3 for the real reason.
Damn! Hope the debris didn’t bugger up other things. Interesting. Never heard this before. Getting close to starting my flathead build. Debating whether to install the remote filter I have. Got the Lucas Classic Hot Rod 10W30 oil. Says high zinc content, but nothing about detergent. Going back through my build thread, I found a post where my machinist mentioned not to install the remote filter c/w the restrictor so I could see how much oil pressure the engine built up in its own, which makes sense for a new build.
That's still risky. Different additives affect each other, I think it's already been mentioned that the extra detergent in diesel oil reduces the effect of the zinc additive, so way more of it has to be added. Worst case non compatible additives can even have negative effects. Any time you add something to the oil without asking the guys who designed the additive package in the oil you are risking the function of those additives, and of the extra ones you add. If you need to add something to the oil to make it suitable for your engine you didn't buy the correct oil.
True. It should be noted that a few diesel oils carry the gasoline ratings ontop of the diesel ratings. But I never subscribed to the diesel oil in a gas engine theory. when I used the yellow bottle stuff I bought Walmart super tech and added the stuff to that. Figured that the cheapest oil possible would meet the minimum spec. At the time I had an MGB and some of those guys are where I got that recommendation. Otherwise it was to run VR1 racing oil
The diesel oil in old engines started because it was a cheap way to get an easily available high zinc oil. when the manufacturers reduced the zinc in regular gas engine oil people got scared they were going to loose cams. At that time, racing oils and hotrod oils were not as readily available and were quite expensive compared to diesel oils. For example, I remember VR1 being $20/L while Rotella was $20/5L, and VR1 had to be special ordered when Rotella was on the shelf. today we have more options for hotrod oils that are high zinc, more affordable and more readily available. Some people still think diesel oil is superior while others are fussed about putting diesel oil in a gas engine. At the end of the day fresh oil and a quality filter is better than no oil.
I can't. They probably "borrowed" that animation and it's not entirely correct. Who knows? It's really not that important in the total scheme of things. The whole point of this is the incompatibility of additive packages. To concentrate on 4 seconds of inconsequential video is beside the point. Go ahead; you have my permission to use oil that is not best suited for your engine. As I said earlier, in the vast majority of cases, it won't do irreparable harm. I knew a guy who never changed his oil or filter; just added a quart when it was low. He was still driving it the last time I saw him. A well built engine can be extremely tolerant of abuse.
That’s what happens when you use gasoline in a diesel engine Heck, I used regular oil in OT diesel engines back in the 80’s and early 90’s. I never had any issues. I just made sure the API rating on the oil met the spec that was in the owners manual.
There's a site (UPIA I think) that you can pull up the additive packages of nearly any oil. The ones with acceptable and maybe even superior packages might shock some of us. Walmart SuperTech is actually really good oil for old shit, so is Traveller from Tractor Supply. Diesel oil has zinc for flat tappet stuff, but I agree it has to be filtered. I've put 15w40 in vintage engines worth more than our whole cars and ZERO issues. And as far as "trapping too much soot", I don't know what the thinking is there. How much soot can an old gas burner make? Not even close to a diesel new or old. Even if it's not a money thing, is a quart of zinc oil really worth $9.00 + hazardous shipping charges? Fear porn. Be smart and research this shit a little. I'm surprised blues hasn't shown up here yet but maybe he's heard this song too many times. Diesel oil didn't shoot the sheriff, or the deputy...
Since Vice Grip Garage calls the stuff in diesel oil vitamins and minerals I only have this to say. My general practitioner put me on a high dose of vitamin D3 and my body reacted negatively to it. But that another story all together. Maybe liver oil will…
To answer a couple questions, the engine is a ‘37 221 Ford flathead, thus has no oil filter. The oil pump pickup screen had some plugging not so much to restrict flow. My theory is the high detergent diesel oil may have caused existing contaminates in the pan to be disbursed and led to a bearing failure. Everything else in the motor looked fine. That bearing is last in line to receive oil in the system. There was considerable gunk in the bottom of the pan and I think the 50wt oil and having been seldom driven the last few years may have caused that before I bought it. I am not surprised to hear the stories of having run diesel oil or Walmart oil or drain oil and it worked out great for you.
https://www.google.com/search?q=i+k...ate=ive&vld=cid:db6d93b5,vid:HblPucwN-m0,st:0 @tubman I don't know anything, but when I research the subject of oils and additives, there seems to be a lot of professional engineers and racing people who support your beliefs. People continue to install new lifters and wipe them out on start up no matter which types of oils they use. There are of course many variables when installing new cams/and or/lifters which can cause these failures. I think (?) the "diesel oil" works in many installations if everything else is correct. Many people have done it and had good results and do not wish to believe that maybe there are better options, or that any other option is worth considering. Don't get disheartened by some of the pushback......some will never take the time to consider an alternative much less actually change. On the other hand........if someone always has good luck with a certain method, I can also understand reluctance to change. The old "If it ain't broke, don't fix it". So, there is more than one way to do things and get good results. That said, I still have a "land line" phone in my house. The point that sticks in my mind when this subject comes up is that there are multiple types of ZDDP. It isn't a one size fits all situation. The explanation as I vaguely recall was that different rpms or different temps (????) affect the activation of each type...........so a specific type or blend of types may be best for different motors or situations. It seems logical that the multi-million (billion ?) dollar oil companies may have a pretty good idea what is going to do the best job for most situations. I'm going to attach something that kind of explains what I'm trying explain about the difference in ZDDP types. Anyone who isn't interested in it should just skip it and continue doing things the way they always have. Remember tho, I'm not saying other things don't work for people........just sayin it doesn't hurt to consider that there may be newer things that might help also. As for the bearing going bad in your engine in 50 miles........my suspicion is that the bearing was already failing and they put 50 weight oil in to mask the noise/prevent bearing failure. When you changed to a lighter oil, it no longer had that protection and failed. Thats just a supposition on my part. There could also have been some debris in the engine that just happened to break loose and destroy the bearing just after the oil change. I don't think the replacement oil itself caused it........but thats just a guess on my part. Notice that this last one......a dedicated break-in oil is specifically only a break-in oil and states that it contains no detergents in order to allow the best attachment to parts during break-in. Now as I said in the beginning........."I know nothing" , but I like to read what the experts have to say and provide it for consumption for anyone who may be interested.
Thanks for your concern, but why would I get "disheartened? I'm not the one using the wrong oil in my engine. I posted an example above about a guy I knew who never changed the oil on his new car, just added some when it needed it. The last time I saw him, they were doing fine. A properly built engine will take a lot of abuse. And I will posit that using diesel oil does not constitute any serious abuse. Hell, some people still run non-detergent oil. I felt there was a need to finally dispel the erroneous implication that diesel oil is better for gas engines than the oil that was specifically designed for them. I have learned a couple of things though. 1. There are a lot of people out there that will disregard proven science for no good reason. 2. There is a real tendency to "shoot the messenger" these days.
Since this is a oil thread: What brand oil can a person buy, right now, that has zinc in it for flat lifter cams? Used to be all I could find was Valveline Racing oil... IIRC its was non-detergent too? Ive been adding a zinc supplement but its expensive
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