Oil weight
 

I thought there was a thread on this but did not show up on a search. What Oil weight do you use? Also there is a debate on detergent v. non detergent. What is best for a not recently rebuilt engine?

Re: Oil weight
 

There are a bazillion discussions about oils.

Some fellas insist on using non-dispersant, can't imagine why.
Some fellas use synthetic.
Most guys use something in between. I've been using Rotella 15-40 for decades.

Re: Oil weight
 

Use good common sense and you will be fine. Any oil is better than no oil but there is no reason to think the the model A engine is any different in theory than any modern 4-cylinder engine except for the obvious improvements. Ford used SAE 20W/20 for cold weather and SAE 30 for warm weather for many many years. The modern multi viscosity equivalent would be SAE 10W/30.

A clean engine is always a good idea. Detergents will do the job. Change the oil on Ford's recommended schedule. With no fancy filter, it needs to be changed more often. That's how you get the crap out of the crankcase is by draining it out more often.

Re: Oil weight
 

The October, 1928, Ford Dealer Service Bulletins say to use SAE 40 in the summer, SAE 20 in the winter.

Winter in South Florida probably does not require the SAE 20, not cold enough. And if you park your car in the garage for winter in Wisconsin, you can probably skip the SAE 20 oil then, too. It will be warm enough in the spring when you start to drive again to use the SAE 40 oil.

Re: Oil weight
 

What does your rebuilder say? Don't get sucked into using straight weight, non detergent oil just cause ol' Henry used it. It makes sludge! Most owners use Shell Rotella 15/40 . with normal usage, change at a thousand miles. I like to add a little STP, It makes the oil stickier so the engine has something in the bearings for when it's been sitting a long time between runs. Make sure the oil level does not get low, this is is a splash lube engine and the level needs to be right.
Terry

Re: Oil weight
 

We have used Walmart HD 20w-50 in our car for years. Four quarts with one bottle of the blue STP oil treatment.

We change once a year or 500 miles. Never down more than half a quart at change.

Motor has less than 10,000 miles on rebuild. Compression is mid 60’s all cylinders. No oil filter, but we do have an air filter. Car does mark it’s spot, very minimal.

Only driven in summer. Enjoy.

Re: Oil weight
 

I use Walmart 20W50 high detergent .

Re: Oil weight
 

ND 30W since car was fully restored and engine rebuilt 2005.

Re: Oil weight
 

IMO, and from what I have read. Some of this is debatable.



Non-detergent multi grade oil was not available in the 30s. Sludge filth settled out and also adhered to the surfaces of the oil system, so the circulating oil somewhat stayed cleaner. Periodic maintenance/service including dropping the oil pan and removing the valve access cover to clean out sludge and the oil pump filter. Issues arose if the shade tree or typical owner for the A skipped or did not know this, and this service was not performed. So non detergent oil is ok, as long as you periodically service the oil pump screen, valve access area, and the oil pan/bottom end. It may even be preferable since the filth settles out and not as much filth is constantly circulating in the oil.


For multi grade detergent oil, all the filth stays suspended in the oil. So unless running an oil filter, all of what is in the oil is constantly being circulated through the moving parts including the Babbit or Inserted main bearings. This is why since my motor is does not have an oil filter I prefer to change every 500 miles. Oil is cheap compared to the cost/hassle of rebuilding a motor.

Re: Oil weight
 

So accordingly I'll assume from the sound of your response you use non-dispersant. Thats your choice.

I'll agree oil is cheap insurance, doesn't take long to change it.

Re: Oil weight
 

16 ounces to the pound.

Re: Oil weight
 

I use Shell Rotella T4 15w40, change every 500 miles, buy the 5 quart or 10 quart containers on sale. The Farm & Fleet store here frequently has mail in rebates that brings the cost down further. Use it due do to price point, it is available just about from everywhere in case I need some quick or on the road (have yet to need any on the road), has a little Zinc in it, and is a decent oil. Is it the best oil? Who knows, probably better oil out there, but if changed frequently is so much better than what was available in the day. And those motors from what I have read lasted 40,000 to 70,000 miles.


As a side note, saw my father once pour something (kerosene?) in the oil in of one of his old tractors and running the tractor for a couple of minutes before draining the oil (he collected old Masseys). I asked him about it. Told me his father did this occasionally on his tractor and on his Model A to flush the motor instead of dropping the pan to clean out sludge. On the tractor added it , ran the tractor a minute or 2 at idle, drained it, then filled with new oil. On the A, added the flush, ran the motor for 1-2 minutes at idle, drained the motor, would pour 2-3 quarts of old non contaminated oil through the distributor hole and breather/fill tube to clean out the oil galley and dipper tray and let it drain. Then filled with new oil. Just saying this is what my Grandfather with 5 kids with a live in house keeper since wife died due to complications of child birth, and was a dirt poor subsistence farmer who sharecropped in Minnesota/South Dakota did - not sure if this is ok to do.

Re: Oil weight
 

Hmm, does 16 fluid ounces weigh a pound. Thats a wonderment, may I'll look it up. ;)

Re: Oil weight
 

While rotella does have zinc in it accord to MSDS it is not in any appreciable amount.

I Typically add ZDDP to my 20W/50 Oil Changes.
to Each there own.

Re: Oil weight
 

Good afternoon. If you know who built your engine, ask them...follow their instructions. Some engines have Babbitt, some Inserts. Some were built tighter than others. Most folks use detergent oil these days. If you have an older engine...and it came to you using non-detergent oil...DO NOT change to detergent oil as it will break old junk loose in the engine and clog up openings. If the car came to you using detergent oil than continue to use it...Good suggestions for types of oil above...Ernie in Arizona

Re: Oil weight
 

First question is, does he use the thermostat ?


Model A by nature is a cold running engine so using a thermostat will make the 'magic' happen using a multi weight oil.


No thermostat, I'd suggest being safe by sticking to a good straight weight oil.


JB of the 'Flat Earth Society'

Re: Oil weight
 

just as a side note: When discussing oil viscosity, the "W" means "Winter", not "Weight"! Oil viscosity in the early days was simply rated as 10, 20, 30, etc. Then oil was improved to flow better at cold temperatures so this oil was rated as 10W, 20W, 30W, etc. So where you might use S.A.E. 20 in mild weather, you might have used S.A.E. 20W in the winter. Then came multi-viscosity oil like 10W-30, which met the 10W rating when cold, and the straight 30 (not 30W) when warm.

Re: Oil weight
 

When I worked with earth moving heavy equipment it was common practice on the inline 6 cylinder Cat motors to pour in 2 gallons of diesel at idle and let it idle a minute of two, then shut it down and drain it. These motors took oil by the gallon, not quart, and that was what the boss told me to do, so we did.
This was in the late 80's and some equipment was from post WW2 (1946ish) and used for 10-12 hours daily. We never had a problem I'm aware of.

As far as type of oil...I'm sure this is right up there with the Blonde vs Brunette vs Redhead discussions...or Ginger vs Mary Anne.

Guess I'll have to track down the previous owner and see what he used.

Re: Oil weight
 

Multi- weight oil, they have the viscosity/flow rate of the first number [lower] and the film strength of the second [higher] number.

Re: Oil weight
 

20w x 50w Walmart with stp