WWII Willys Jeep winter oil recommendations

[Silber Igel]

Here is a link that may be helpful....

http://www.1945gpw.com/c-3-G503_WWII_Jeep_Go_Devil_Engine_Change_Oil.aspx

Note: The author says this engine uses 30wt and he uses a 10W30. Which would appear acceptable. Heavier grades will make it very hard to start in the winter months. And, heavier grades really aren't necessary. Nor is a synthetic. I'd use a 10W30 SM rated conventional or syn blend, like Motorcraft (or one of the Conoco-Phillps clones)which would be a good compromise). The Go Devil is a low output engine... IMHO, synthetic would be way over the top.

Not having seen one of these in awhile, I think they are 4 qts plus a quart for the filter ... give or take.

I'd skip all the 'cleaners' and 'flushers' since this engine is probably going to get frequent oil changes. Just change the filter at the same time as the oil change.

Here's something that might be interesting...
See pp 138... http://books.google.com/books?id=K5-_RMz...;q=&f=false

 

[Trvlr500]

I agree with you, Silber. I can't believe what people are recommending for this 1943 Jeep engine. It's been running on non-detergent straight 30 weight and the recomendations I see here are Mobil 1 0w40 and other high detergent synthetics/dino's?

Why don't we just recommend he put some sand in there to accelerate blowing the engine. I doubt the oil is the biggest reason it is not starting well in the first place. It is probably battery/charging system/carburetor related.

The 30 weight may be on the thick side for sub-zero temperatures so change to 20 weight non-detergent. My bet is that putting a super detergent modern oil in that thing will loosen up all the gunk way to fast, plug an oil gallery and possibly fry a bearing or clog something else up like the ring lands grinding away at the cylinders in the process.

If it were my jeep and I wanted to switch to a high detergent synthetic I would run 20 weight non-detergent in it with 1/2 the recommended dose of Rislone (which I've used for decades with great success) which works very slowly for a few oil changes over a LONG period of time and THEN take the chance on putting a modern high detergent oil in it.

Actually, if I KNEW for a fact it was the thicker oil causing the hard starting which could very well be contributing to it I would use the thinner 20 weight non-detergent in the winter, 30 weight in the summer, get the oil filter hooked up and not even consider a modern high detergent synthetic (or the Rislone) until I rebuilt the engine some day.

If it's having starting problems fix it with thinner oil and carb work but IMO putting a high detergent synthetic or conventional in it is a BIG mistake. I don't care how many filter and oil changes he does. All it takes is one small chunk of the junk in there to plug an oil passage and it's good bye engine. Not a chance I'd take if it was MY Jeep.

 

[Trvlr500]

Originally Posted By: Gary Allan
I would use 20w-20 conventional.


I would second that and add that a non-detergent (if that is what they recommended back then) be used.

 

[OVERKILL]

Originally Posted By: Trvlr500
I agree with you, Silber. I can't believe what people are recommending for this 1943 Jeep engine. It's been running on non-detergent straight 30 weight and the recomendations I see here are Mobil 1 0w40 and other high detergent synthetics/dino's?

Why don't we just recommend he put some sand in there to accelerate blowing the engine. I doubt the oil is the biggest reason it is not starting well in the first place. It is probably battery/charging system/carburetor related.

The 30 weight may be on the thick side for sub-zero temperatures so change to 20 weight non-detergent. My bet is that putting a super detergent modern oil in that thing will loosen up all the gunk way to fast, plug an oil gallery and possibly fry a bearing or clog something else up like the ring lands grinding away at the cylinders in the process.

If it were my jeep and I wanted to switch to a high detergent synthetic I would run 20 weight non-detergent in it with 1/2 the recommended dose of Rislone (which I've used for decades with great success) which works very slowly for a few oil changes over a LONG period of time and THEN take the chance on putting a modern high detergent oil in it.

Actually, if I KNEW for a fact it was the thicker oil causing the hard starting which could very well be contributing to it I would use the thinner 20 weight non-detergent in the winter, 30 weight in the summer, get the oil filter hooked up and not even consider a modern high detergent synthetic (or the Rislone) until I rebuilt the engine some day.

If it's having starting problems fix it with thinner oil and carb work but IMO putting a high detergent synthetic or conventional in it is a BIG mistake. I don't care how many filter and oil changes he does. All it takes is one small chunk of the junk in there to plug an oil passage and it's good bye engine. Not a chance I'd take if it was MY Jeep.



I bet there are thousands of Toyota, Chrysler and other "sludger" engines out there that look WAY worse inside than this old girl.

If the engine IS somewhat gunked up, and one wanted to slow the cleaning process, he could mix 1L of Mobil 1 0w40 (or his detergent oil of choice) with his normal non-detergent fill. That would severely dampen the cleaning effects, and he could gradually ramp up to a full fill after he stops getting "loaded" filters.

Since it has a cartridge filter setup, if it is anything like our old 50's Ford ones, they were VERY easy to change, took all of 30 seconds.

 

[addyguy]

First, I'd like to say that is one of the most awesome pics I've ever seen on here! Wow, nice rig!

Anyway, can I ask what he's doing driving a classic like that in the winter??? Isn' he worried about it rusting away?

Anyway, I'd be careful with this one - if this engine has run non-detergent oil it's whole life, it's FULL of sludge. Any move to a deterget oil will dislodge some or all of this sludge, and cause problems. Don't be surprised if this engine locks up when the dislodged sludge blocks the oil pump pick-up.

Is your friend good at taking apart engines? Only proper way to do this is to take off the pan and valve cover, and clean all the sludge out, and then run some short oil change intervals to flush the rest out. Then I'd use a good 15w40 in it.

 

[OVERKILL]

Originally Posted By: addyguy


Is your friend good at taking apart engines? Only proper way to do this is to take off the pan and valve cover, and clean all the sludge out, and then run some short oil change intervals to flush the rest out. Then I'd use a good 15w40 in it.


Yup, that's a great suggestion too! There is a possibility that it is NOT as bad as we might assume though. We had one Chris-Craft I6 that had a lot of hours on it and needed a valve job. When we took it apart, it REALLY didn't look as bad as you would expect an engine run every summer since 1945 to look.

I'm not familiar with this engine so I have no idea if it has removable covers of some sort, like one on the side for the cam/valves. But if that is the case, it could be pulled to give an idea of the internal condition.

And if he's got pics, even better! LOL

 

[OVERKILL]

OK, found some images:

The cover in the first picture can be removed to give an idea of the internal cleanliness.

 

[OVERKILL]

Block:

Guts:

 

[Zaedock]

Meth, I run 10W30 in my F134. I think there's SuperTech in there now. It runs fine. Always starts at any temp, even after sitting. If your bud is going to drive it often in winter, go with a dino (Quaker State, Pennzoil conventional, etc...)5W30 and change it to a 30wt for summer. Definitely run a detergent oil.

These engines do not need syn or anything fancy. Mine is 50+ years old, all original, and runs fine on conventional.

Hey, ask your bud if he's in any clubs in New England. I'm pretty active and may have seen him around. Ask him if he's heard of the Great American Jeep Rally. My club has been putting it on for eight seasons now, and it has become the largest Jeep rally in the east and possibly the country.

Happy Trails.

 

[saberz]

Thats a very nice and historical vehicle. Any 30 weight oil will be fine(5w/10). I'd do as suggested and run conventional with very short oci's and get the filter system in place to clean it all out.

a straight 30 in the winter isn't really easy on a vehicle for starting, and factor in any "possible" build up from non-detergent use(if it hasn't been run often etc) then I'd really go for a 10w30.

 

[rclint]

I would run a straight weight oil in that jewel, HDEO 30 Delo, or Rotella, no need any big time high tech oil, and I would venture to guess he has not hurt anything by not running a detergent oil, however I would... given the choice of oils available in the local pick-em-up stores. Delo HDEO 30 would be a hard one to top, Shell Rotell HDEO 30 would be second, however I do use both depending which is on sale at the time (yes you can even catch SAE 30wt on sale)

 

[Gunatics_Adler]

Id use some high mileage 10w30 such as Quaker State Red Bottle. It will help keep it clean, keep it from leaking, and it has higher levels of anti wear agents for that piece of history. Plus its pretty cheap.

As a professional historian it warms my heart to see an old vet like that jeep still going. My father and I rebuilt a WW2 Ford made Jeep engine for a guy. It gets used every year when he goes prospecting up north.

 

[saberz]

Well the reason I recommended a 5 or 10w is for the cold start. As this is an issue stated in the above posts. I am not familiar with the straight 30 weights abilities in the cold.

 

[mechtech2]

Is that a 6 volt system?
Everything has t be in perfect shape for good cold weather starting.
EACH end of the battery cables, where they seat, should be cleaned down to shiny metal.
Your ignition parts should be as good as you can get them.
Is the fuel old? Lots of problems if it is.

Winter oil? No reason to not use a 5w30.

 

[Drew99GT]

How about trying this stuff.

starting fluid

 

[ledslinger]

I think a 10w30 HDEO would be great for this. If he wants to run it in cold temps this is a good application for an engine and battery heater. Easier than converting to 8 volts. 6 volt system (as noted) has to perfect for cold weather. Be sure the cables are really big.

Get the oil filter hooked up ASAP!

 

[Jim Allen]

My 1942 WIllys manual (TM-10-1513) lists grade 30 for summer and grade 10 for winter. I don't know of any multigrade non-detergents, so the owner is left to do oil changes for winter and summer, with the winter being a 10 or 20 grade. If the neat pics posted are of the owner, it looks like he's a reenactor and they often have winter maneuvers and the old jeep could see some time in the mud and snow and that would dictate a lighter oil. It would be just as hard for the owner to "start up" after spending the night in a WWII era mummy bag and pup tent as it is for the jeep sitting outside right next to it!

If the guy has used non-detergent, IMO, he should probably stick with it unless he's willing to go through some extra effort. That could be in the form of a partial teardown or just frequent changes as the gunk breaks loose. I'm scared of that latter option because I tried it and failed with an old Dodge flathead (due to my own laziness and ignorance mostly). Look under the tappet covers (and adjust those valves while at it) and if there's lots of gunk, tread carefully. If clean, you might get by with the frequent oil change deal. Once free of the "sludge monster" I would use a 10W30 HDEO.

The engine came with a bypass, cartridge filter but they are often blocked off by current owners because of a persistent rumor. The stated reason is that the bypass filter bleeds off oil volume and starves the main bearings. Not sure I believe it. Some failures may have been blamed on that when it was really due to other causes. A properly rebuilt engine with a good oil pump, bearing clearances and a properly installed filter shouldn't have oil pressure problems. Never been motivated via ownership to thoroughly debunk the issue, or prove it, but it would be job 1 if I had a jeep with the filter blocked off. A bypass filter is better than a "no-pass" filter.

 

[methusaleh]

Thank you all for your replies! I think we are leaning toward a nondetergent 20W and running a 1/2 dose of Rislone, as someone suggested. Although I need to sit down and really re-read this entire thread and take some notes.

The photo is from a few years back when he first got the Jeep. Since then it's been remarked to reflect the unit that the owner re-enacts.

I am not sure what kind of choke is on there, I know there's a knob that looks like a choke to me, I will have to ask.

We just got done re-doing the whole electrical system, as well as plugs, plug wires, etc. It is 6V. All wires and connectors are brand new, new Optima red top battery, and the system seems to provide adequate amperage.

 

[Drew99GT]

I wouldn't do the Rislone as it's intended purpose is to clean.

 

[djlinux64]

SPOILER ALERT

This is not an oil problem. It is a fuel delivery problem. Generally speaking, oil problems only begin to manifest themselves when starting below 0 Fahrenheit ambient on 50 weight straight weight. Follow the oil advice of others to ensure your engine is in good condition for a long time. Now fix your fuel delivery problem to make sure your engine runs!

First of all, the carburetor is most likely in need of a good clean and reassemble. Since ethanol added fuel will make the engine run leaner on all circuits, raise the float level by a 1-3 millimeters by gently bending the floats up. Absolutely must be done if you run on fuel that contains ethanol or you will run lean and hence the start up problems he is having. The cold weather is only going to exacerbate his problem by making the engine run even more lean.

If you are still having problems, check your cold cranking voltage across the battery. If it drops down to around 6 volts you need a new battery. A good battery sits at and above 12.6 volts. I am assuming your charging circuits are functional and you don't have an over-voltage situation because you can barely crank. However, make sure your battery is not over 14 volts and check the electrolyte level.