According to Allis literature a straight weigh non detergent is what they called for. Now days I use 10W30 in my 45 cause I use it year round. My B only gets used to mow with and has many hours on it so I run straight 30W in it.

Depends on the age and the condition of the engine.  If it has been some time since the engine has been overhauled then I would definitely use 30W NON DETERGENT OIL.  The reason being that the detergent oil has the ability to clean out the gunk in an older tractor.  While that is fine with an engine that has been recently overhauled it may not be so fine with a unit that has an engine that has not been recently overhauled.  The gunk could be keeping the tractor from burning or leaking oil.  We had more than one situation when we were selling.  We always put non detergent oil in the engines of used tractors. 

It is a 1952 B and I have no idea to any of it's history.  It's been only living with me now long enough to clean and paint it.  The oil I removed was very dirty.  As far as  a overhaul there were some receipts for rod bearings and the head was clean of all paint leading me to believe that the head was off anyway but I don't think that was very recent.  There was a very small amount of slug under the rocker arm cover. 

Why do some people freak out if they hear of putting detergent oil in an old briggs even if it was clean? they act like it will cause it to fail.

Just ran across this forum and joined due to my history of working in the tractor engineering department at West Allis and love of old tractors (grew up on a farm in the 40's and 50's).  Like several other "motor" related forums that I participate in, oil is a frequent and interesting subject.

You probably will be fine with most any oil you use---------if you don't start it often or in cold temps or put much load on the tractor.  However, if it were my tractor, I would use Mobil 1 5w-40 diesel oil in it.  This oil is also rated for spark engine use, will provide quick lubrication on start-up, and provide a little extra film strength if there are some worn parts in the engine.  It also has more zinc additive in it for bearing protection then some of the newest oils.

If the engine is full of sludge (unlikely if recently worked on), the sludge will create problems whether you use detergent oil or not.  Unless I was going to re-sell it quickly, I would prefer to get an engine clean using a good detergent oil and then deal with any problem that might show up. 

The best thing is to put in a good modern oil, and then do an oil analysis (less than $30) when you think the oil should be changed.  That will tell you something about the condition of the engine and whether the oil really needed changing at that point or not.

My 2 cents, anyway.

Gerald J. wrote: 5W-40 synthetic will find cracks and old gaskets that 10W40 won't. I have a VW Golf and the factory would like 0W40. It disappears too rapidly, to need changing with 75K on the engine. Part is leaking out a crack in the diecast oil pan. 5W30 semi synthetic stays in a lot better. Gerald J.

That's hard to understand.  Both these oils will be 40 weight oils at operating temperature or about 15-17 cSt (centistrokes) at 200 degrees.

At 50 degrees, both the 5w and the 10w will be much thicker.  The 5w will be around 280 cSt  and the 10w will be about 460 cSt.

To put it another way, if either the 5w or 10w oil leaks when setting, they should both pour out when at operating temp.  The only thing that be happening is that the cracked oil pan might, just might, seal itself up as the engine heats up and the metal expands.  

You have to admit that choosing oil based on a cracked oil pan rather than what's best for the bearings may leave a little to be desired. 


Edited by 427435 - 18 Nov 2010 at 3:16pm

First off I want to thank everyone for their advise and thoughtful opinions.  Well, here is what I decided to do.  After draining the oil and waiting until it stopped dripping, so it wouldn't go in my face, I looked up in the drain hole and could see a relatively clean engine.  I took an acid brush and bent it in a U shape, put it in and explored. I found that the sludge was confined to the lowest point of the pan.  That saucer like part of the pan where the drain plug is.  I kept on wiping and cleaning with the brush and then using my squirt oil can I pumped oil in the hole and working it with a bottle brush until that oil came out clean. Then I put the plug back in and poured in a qt of oil that I had on the shelf.  I let it set, drained it out and it came out clean.  I now have petroleum oil 10W30 which I will change sooner.  Eventually I will go to Mobil 1.

" That's hard to understand.  Both these oils will be 40 weight oils at operating temperature or about 15-17 cSt (centistrokes) at 200 degrees.

At 50 degrees, both the 5w and the 10w will be much thicker.  The 5w will be around 280 cSt  and the 10w will be about 460 cSt."


 the way i was told that an oil that
say 5w 30 is that when the oil is cold
it will act like a 5 wight oil but when
it get hot it will act like a 30 wight oil
i know that your think that when the
oil get hot it get thin  not so they tell
me that sense they used polymer in
the oil the polymer is per say plastic
they take a piece of it and roll it up
in a ball thus when it cold it get
small and when you heat it up it
expand and get bigger there for
the oil get thicker when it heat up . 
best  is to put in a good modern oil
then the old straight weigh non detergen
IMO   HTH
B:-)    Dnoym

here some thing i found on the net
At cold temperatures, the polymers are coiled up and
allow the oil to flow as their low numbers indicate.
As the oil warms up, the polymers begin to unwind
into long chains that prevent the oil from thinning as
much as it normally would. The result is that at 100
degrees C, the oil has thinned only as much as the
higher viscosity number indicates. Another way of
looking at multi-vis oils is to think of a 20W-50 as
a 20 weight oil that will not thin more than a 50
weight would when hot.

Multi-viscosity

Multi viscosity oils work like this: Polymers are
added to a light base (5W, 10W, 20W), which
prevent the oil from thinning as much as it
warms up. At cold temperatures the polymers
are coiled up and allow the oil to flow as their
low numbers indicate. As the oil warms up the
polymers begin to unwind into long chains that
prevent the oil from thinning as much as it
normally would. The result is that at 100
degrees C the oil has thinned only as much as
the higher viscosity number indicates. Another
way of looking at multi-vis oils is to think of a
20W-50 as a 20 weight oil that will not thin
more than a 50 weight would when hot.

Multi viscosity oils are one of the great

improvements in oils, but they should be

chosen wisely. Always use a multi grade

with the narrowest span of viscosity that

is appropriate for the temperatures you

are going to encounter. In the winter base

your decision on the lowest temperature

you will encounter, in the summer, the

highest temperature you expect. The

polymers can shear and burn forming

deposits that can cause ring sticking

and other problems. 10W-40 and 5W-30

require a lot of polymers (synthetics excluded)

to achieve that range. This has caused problems

in diesel engines, but fewer polymers are better

for all engines. The wide viscosity range oils, in

general, are more prone to viscosity and thermal

breakdown due to the high polymer content.

It is the oil that lubricates, not the additives.

Oils that can do their job with the fewest

additives are the best.

Very few manufactures recommend 10W-40

any more, and some threaten to void warranties

if it is used. It was not included in this article for

that reason. 20W-50 is the same 30 point spread,

but because it starts with a heavier base it requires

less viscosity index improvers (polymers) to do the

job. AMSOIL can formulate their 10W-30 and 15W-40

with no viscosity index improvers but uses some in

the 10W-40 and 5W-30. Mobil 1 uses no viscosity

improver in their 5W-30, and I assume the new

10W-30. Follow your manufacturer's recommendations

as to which weights are appropriate for your vehicle.

D:-)     Dnoym

Just curious who is voiding warranty over 10-40? On late model automotive engines you can cause problems from not using to proper grade because of some non lubricating functions that oil is used for. Cam phasers, hydraulic chain tensioners, high pressure oil controlled injection on Navistar diesels just to name a few.

This is pretty interesting. But now where does the Lucas oil treatment come to play. What does it do to the oil. I sell it where I work and lots of people swear by it and I have started using it myself. I drained the oil out of one my vehicles the other day and it had  lots and lots of miles on the oil change  (I get behind sometimes). The oil was black as it could be but still had a nice slick feel to it. The oil was a generic we sell called fleetguard with a pint of Lucas added.JP  

Check the MSDS for Lucas and the other motor honeys. All it is is thick  oil. Nothing more, nothing less.

Gerald J.