The Stovebolt Site Forums The Shop Area Engine Shop Oil detergents - first change/ old engine

Haven't seen an oil thread in a while...this always seems to ignite some passionate responses.

I've dug through some old threads that suggest one ought to be careful with "high detergent" oil in an old, probably sludgy, stovebolt engine. That they will stir up too much of the old crap.

I've seen some posts that the detergent is good and not to worry about it. 15w40 seems a very popular choice for those in this camp.

Thoughts?

Delo400 works fine. Just a thought. Pfarber is bound to chime in.

What year engine? GM recommended detergent oil as an "option" prior to 1954, but specified multi-grade detergent in 1954.

If single-grade (and/or non-detergent) oil has been used, you could have sludge/gunk that could go into suspension if you change to multi-grade/detergent.

I'd remove the oil pan, clean the sludge out; and, remove the valve cover and see how much sludge is there (and try to clean it out).

This will probably start something.
First of all it depends on what you are starting with. We will eliminate engines that have been torn down, cleaned and rebuilt.
An old engine that has set for a long time but is supposedly in running condition. I like to run them if possible to evaluate before restoration starts.
Drain the oil. If it has a filter, change it. Refill with a HD multi weight. (lube the cylinders and make sure it has coolant)
Run the engine until it is warm (10-25 min.)and do the evaluation.
Drain the oil as soon as the engine stops and replace the filter. Inspect the oil and determine if it is slightly dirty, very dirty or gross.
Slightly dirty - repeat the process but run for 30 min high and low RPM's and check the oil again. If it still looks good you won the lottery.
Assuming that you aren't planning to pull the engine down (or we wouldn't be having this discussion)
Any of the others- Remove the oil pan and clean. Same with valve covers or lifter covers and clean out all you can.
Reassemble, fill with new oil and run for 1/2 hr. dump oil and filter. Refill and drive for 100 mi and dump oil and filter again. Depending on how good or bad the oil looks repeat at 500 mi or 1000 mi then go the usual change schedule.
I never recommend using engine cleaners. If Hot HD oil doesn't remove it, leave it alone.

If you do not know the history of the engine, I would drop the oil pan.
If I knew the history of the engine from someone I trusted, I would still drop the oil pan.
The sludge can be so deep and so thick, it will not budge from any kind of detergent oil or multiple oil changes in my experience.
Carl

I run 15w40 in my 49 216. It stays somewhat clear for perhaps 100 miles then turns black. It is still somewhat translucent but barely.
One thing to keep in mind is that the color of the oil has no bearing on it's additive package and ability to clean and lube, it's more of an indicator of the condition of your engines internals.
These old powerplants were originally run w/non detergent oil which allowed the soot and other combustion byproducts to deposit and accumulate on the engines internals.
Modern detergent oil suspends these byproducts and carries them with it on oil changes. It also continually cleans the inside so it's normal for the detergent oils to turn black. It's an indication that the oil is doing it's job.
If you've ever owned/serviced diesels you'd have quickly discarded any concern over blackened oil

I'm fully in the multigrade/detergent oil camp in these old powerplants....

Dave

To Tim's question: this is a 62 model 235. So, post-detergent era per your post.

Valve train is fairly nasty. I was thinking a little running with fresh oil might help, but perhaps I should try to clean.

I guess just spray a little diesel or kerosene around and scrub?

My 2 cents: 216 or any splash oiled motor, Pull the pan. Not hard and lets you see inside. Valve cover gets pulled any way to see if all is well up top. This is for peace of mind. I do drain what ever is in there to start with. If I see a lot of sludge in the pan and on the head, it is a good time to turn by hand if you can, and clean what you can. Old paraffin based oils I think are the reason for the sludge. Diesel fuel is a good solvent for this task. Detergent oil like modern oils cause no harm. If the crud in there comes loose it won't matter why it came loose it will do what it does. Never any good. I have put the pan back on after cleaning and with a new filter in place you can fill with diesel and turn the pump with a drill. You can see if the rockers get oil and if it will make any pressure. The engine is not turning so the risk of crud causing damage is very low. The same applies to insert bearing engines. Sludge in some more modern engines is a concern. Any oil that has set for a long time, has water in with it. It becomes very corrosive over time. I have no good thoughts on letting that stuff stay in there. So there you have it. Old or new. Get the big stuff out and then let the modern detergent do what it does. Any other ideas are welcome.

If you have visible sludge build up I'd manually clean the internals and start with the proper weight detergent oil. If you get a clump of sludge stuck in a gallery or passage or worse, smeared on a bearing surface bad things will happen. The GOOD part is that the rockers are the last parts to be lubricated, so the sludge will most likely fall into the crankcase. The BAD part is that the oil pump won't care that it's sludge and pump it back through the system.

Run 20 or 30 weight detergent oil. Multi weight is fine... 15W40 is much to thick IMHO. 5W20 or 5W30 unless you are in the desert/temps over 100F. Its all about start up wear and getting that initial boundary layer of oil on the bearing surfaces. This will explain it all:

http://www.upmpg.com/tech_articles/motoroil_viscosity/

My experience is diesel fuel is a horrible solvent, ditto for kerosene. It's oil. The additives may do some light cleaning, but not much. The fact that when it seeps out of a motor its HOT probably does more 'cleaning' than the oil itself. And you surely don't want to add it to a crankcase. Yes, way back manuals would tell you to use kerosene (10% or 1 quart in place or regular oil) or even mineral oil.. but there are MUCH BETTER solvents that are available... SeaFoam is probably most cited.

Other side of question:
Recommendation for a completely rebuilt 1950 216 engine.
Harold

Other side of question:
Recommendation for a completely rebuilt 1950 216 engine.
Harold

15W-40 any brand you choose, Nuff said!

Cleaning an older engine- - - -regardless of the opinion of our resident fertilizer producer, Diesel fuel is an excellent solvent. So is Kerosene, although the #2 Diesel has a little bit of lubricating ability since it's slightly more oily. #1 diesel is virtually identical to Kerosene- - -so is jet engine fuel. Overfill the engine 2-3 quarts with Diesel fuel after a fresh fill with cheap 30 weight oil, crank it up, and run at a fast idle for 30 minutes. DO NOT DRIVE! The crankshaft splashing the mixture around does a much better job of scrubbing the lower end than you'll ever do with a brush. Pull the valve cover, give the hot valve train a good scrubdown with diesel and a stiff bristle brush. Drain and refill with 15W-40, and change the filter element. Mission accomplished.
Jerry

My truck is confined to my attached garage at the moment.

Will the "diesel in crankcase" procedure generate any smellier-than-usual exhaust? If so I might have to wait on it a little while.

DEFINATELY DO NOT Run it in a closed garage.
Attached or Unattached.
It,s gonna be smokey and
Would be VERY DEADLY!!!!
steve sr.

LOL. Yes, I know enough to at least open the door.

Question was more around the smell. We are moving to a new place soon where driveway work will be more feasible. It'll just have to wait.

Wife is not very proud of the exhaust smell as it is.

It will definitely be stinky- - - -not necessarily smoky. Hot diesel fuel has a smell all its own. I'd recommend plenty of ventilation- - - -a big box fan at least, and outside on a windy day would be better.
Jerry

I imagine the diesel /oil mixture is going to be pretty good at finding leaky gaskets?

Perhaps another reason to move outdoors.

Definitely! Sometimes the only thing keeping these old rigs relatively leak-free is a good layer of crud, inside and out!
Jerry

So I guess HRL/fertilizer producer honeymoon is over. Oh well, it was nice while it lasted.