10W-30 instead of 20W-50

Status
Not open for further replies.
Joined
Jan 3, 2006
Messages
1,958
Location
Ohio
Just curious, I have a 1977 MG Midget with a 1500 engine. I've always used 20W-50, since the owner's manual says to use that above 60 degrees F. Below that you can use 10W-30. Would 10W-30 be okay over 60F? Only reason I ask is it seems like it takes a second or two for the oil pressure to register, although I don't know if that's because of the skinny capillary tube running from the engine up to mechanical oil pressure gauge. This engine is rather notorious for wearing out bearings (crank, rod, and thrust), but would 10W-30 improve the time to build up oil pressure, and still give sufficient pressure at idle when hot? Normally it's about 20-25 PSI when hot at idle.
 
no use either 20W50 or 15W40. Your bearings will thank you in the long run. Most european cars love thicker oil. If you use synthetic 15W40 you should have no problem. your other option is to run 10W60.
 
The rule of thumb on oil pressure is 10lbs per 1000 rpm. 20-25 at idle is good. I would stick to 20W50 or maybe a 15W40 HDEO.
 
You're getting good advice. The Midget/Sprite engine was designed about two weeks after the discovery of fire. It was obsolete before you were born. It's a good engine, but you have to keep up with the valve adjustments and all those other pesty details that were eliminated by Japan about twenty years ago. My cousin had a Morris Minor with the same engine and he was always under the hood doing something, but he loved that car. He always used Castrol 20w-50, but part of that was the high mileage and his lead foot. When I rode with him, he would scare the cr@p out of me driving around freeway on ramps sideways. Sometimes while we were sliding around, drifting toward the apex, him shifting gears and really getting after it and we'd get blown off by a soccer mom in a mini van full of kids on the way to the shopping mall, that did not even know that she had just passed Mario Andretti at the absolute limit, driving the perfect line. You have one of the last real fun cars that us common folks can afford, I hope you enjoy it.
 
I drove an old VW Jetta for lots of years and over 200K miles. It didn't like anything but 20w50 year-round. Even in the coldest of weather. I tried experimenting a few times with 15w40, 10w40, and even 10w30, but the oil pressure sensors kept going off and the car would get hot at idle when stuck in traffic.

I'd stick with the 20w50, especially considering it's served you well.

Also, just a side note: Irv Gordon in his 2 million mile Volvo has used only castrol dino 20w50 in his old Volvo, so you're in good company.
 
quote:

Originally posted by Louie's gone fishing:
You're getting good advice. The Midget/Sprite engine was designed about two weeks after the discovery of fire. It was obsolete before you were born. It's a good engine, but you have to keep up with the valve adjustments and all those other pesty details that were eliminated by Japan about twenty years ago. My cousin had a Morris Minor with the same engine and he was always under the hood doing something, but he loved that car. He always used Castrol 20w-50, but part of that was the high mileage and his lead foot. When I rode with him, he would scare the cr@p out of me driving around freeway on ramps sideways. Sometimes while we were sliding around, drifting toward the apex, him shifting gears and really getting after it and we'd get blown off by a soccer mom in a mini van full of kids on the way to the shopping mall, that did not even know that she had just passed Mario Andretti at the absolute limit, driving the perfect line. You have one of the last real fun cars that us common folks can afford, I hope you enjoy it.

lol.gif
Got a kick out of reading that. Sounds like 20W-50 is what to stay with. Yep, the technology it has is entertaining. It had electronic ignition and an FM radio from the factory, yet you had to pull over and raise the hood to open the heater valve if you wanted heat. Likewise, you periodically have to top off the carburetor dashpot oil. My girlfriend still can't believe what the routine maintenance (and not-so-routine maintenance) requires. The electronic ignition (destined to fail, since it was designed by Lucas) was the reason it broke down for the previous owner and got relegated to his garage for nearly 18 years. I rescued it, put a Pertronix ignition in, and it's a blast to drive. Like a street legal go-kart, and it's about the same size as one
shocked.gif
. Thanks for the info!
 
Dave

Doug Hillary posted this when discussing our old cars and oil

Quote
I did my Engineering training - six years - with BMC - in NZ and in England (Stewart & Ardern, "The Vale" Acton - 1962-63)

The export prototype Mini was my first development project in NZ in 1959
The tragedy of BMC was the lack of funds for refinement and, in the end funds were taken from the very viable Leyland Trucks Division to support the cash hole in the Car Division. However that was long ago and far away

Oil changes on the Mini were done at 1000 miles without fail - but they leaked SO much anyway it probably didn't matter much!
The OCI for other BMC engines was 3k miles max. and Castrolite (20w-20) or Castrol XL (20w-30) were the most common lubricants. Mobiloil Special 10w-30, or BP Visco-static were "not good" in these engines in the 1950-60s!

It is also interesting to note that engine life in cold and hot climates is very similar if the Manufacturers servicing advice is adhered too. Therefore, similar cars starting from a base low (cold) of -25C and +25C will almost always have the same engine life other factors being the same. Does this suggest that the design of the cooling system (for quick warm-up) and the Engineer's designed core temperature have much to do with the engine's ultimate life?


When the Mini came out in 1959 a specially formulated oil was required Duckhams 20w-50. It was the first "heavy" multigrade - 10w-30s had been out for years. You could use the same oil viscosity today in the same engine without an issue of course. We used 10w-30 20w-20, 20w-30, 20w-50 and mono HD oils in BMC "A" "B" and "C" series engines around the world in various markets without problems - as you could today. We got very good engine life at that time.
The '74 MGB I sold a couple of years ago ran well on 15w-50 and 5w-40 synthetics - the 5w-40 wasn't in the Handbook but met the original viscosity "intent" of the Handbook
The engine felt better on the 5w-40 though


the "intent" with the B series engines was to run as I recall 20-20W (Castrolite) or 20w-30 Castrol XL. We also used HD30 oils such as Delo etc. Later this included 20w-50 as these oils became available. We used 10w-30 too and had exceptional engine life with all of these mineral oils if the car was serviced reasonably well. I know of one doing well over 300k miles without work (except for a water pump as I recall)

The availability of synthetic oils changed all this
Unquote
 
Try a 5W40. You can buy Rotella-T Synthetic for $12-$14 a gallon. If that is too much then Delo 15W40 would be my next choice. 10W30 is not a good match for this engine for anything other then short trip round town driveing. IF you really want to use a lighter oil try Synergen 0W30LTS or Redline 10W30 these oils are really Robust but not be too friendly to old 1977 oils seals!
 
There are 2 new 15w-40 "blends" out there. Valvoline DuraBlend in 15w-40 and Castrol Syntec Blend 15w-40. Both are likely outstanding oils, but noone here has tried them yet. Another option is a Hi-Miles 10w-40, Castrol GTX HM is quite thick. A nice modern oil for a vintage car is a good tweak.
 
quote:

Originally posted by iowanbrick:

quote:

Wasn't one of the early MG engines actually designed for a farm tractor?

No, you're thinking of Volvo.
grin.gif


Actually, it was Triumph that used an engine that came from a tractor, used in the TR-3. Come to think of it, since the '75-'79 MG Midget used a Triumph engine, I wonder if it shares the same ancestry.
 
quote:

Originally posted by Dave Sherman:

quote:

Originally posted by iowanbrick:

quote:

Wasn't one of the early MG engines actually designed for a farm tractor?

No, you're thinking of Volvo.
grin.gif


Actually, it was Triumph that used an engine that came from a tractor, used in the TR-3. Come to think of it, since the '75-'79 MG Midget used a Triumph engine, I wonder if it shares the same ancestry.


The tractor engine was used the the TR2, TR3 and TR4. Some sources say it was actually used in an early post WWII car (Vanguard?) before it was used in tractors.

The MG Midget was a badge engineered Austin Healy Sprite with an A series Austin engine.
 
Actually it was the MGC which had a tractor's inline 6 cylinder engine. And the MGC drive like a tractor, too. It was a good stout engine but evicently farmers are not bothered by big oil leaks like city folks are with their cars. If you could keep up with the oil leaks, you never had to change the oil.
 
I was being a bit faceatous when I said that Volvo engines were based on a tractor engine. However, I recall reading that the Volvo 4 bangers have the block, bearings and crank from a stationary diesel, which would explain their weight and longevity.
 
Status
Not open for further replies.
Back
Top