Hello all,
I've been restoring a '69 Sears Suburban SS12 with the original Tecumseh HH120 in it. The PO said it didn't use any oil, and for the short time I ran it before tearing it down, I didn't notice any consumption.
I tore the engine down, decarbed the head and piston, the rings are tight, no scoring on the cylinder wall. I wanted to replace the oil seal on the crankshaft since it was apart, and I cleaned what I would call a normal amount of sludge out of the crankcase.
I have no idea what the PO ran in it as far as oil, any recommendations?
I may mow the lawn with it a few times a year, but it's more of a dedicated workhorse, pulling wagons around my property in the summer and plowing snow in the winter.
Thanks,
bobcat2
Oils for old engines
- Thread starter puma4440
- Start date
I had a John deere 112 with an HH100 that did quite well with Amsoil Ase 10w30 Small engine oil.
If you want an off the shelf oil I would go with a HDEO, like Rotella or Delo.
5w40 would be fine year round. 10w30 or 15w40 would be fine in the warmer months.
Back in that day, straight SAE 30 would have been the rule. I've seen it posted here by some of our elder sages that good old dino SAE 30 had a 3.7 HTHS viscosity. Something in that neighborhood seems appropriate. Personally I like M1 10w-30 High Mileage with 3.5 HTHS viscosity, but there are plenty of other options.
In this here Tecumseh manual they call for a straight 30 weight.
My opinion is you'll likely do fine with a 5w-30 or 10w-30.
Good luck!!!
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JHZR2
Staff member
Originally Posted by Astro_Guy
Back in that day, straight SAE 30 would have been the rule. I've seen it posted here by some of our elder sages that good old dino SAE 30 had a 3.7 HTHS viscosity. Something in that neighborhood seems appropriate. Personally I like M1 10w-30 High Mileage with 3.5 HTHS viscosity, but there are plenty of other options.
Originally Posted by walterjay
I would use any 5W-30 dino motor oil off the shelf. This would work for both cold and warm weather.
Manufacturers these days say a 10w-30 performs just like a straight 30 at operating temps and is a direct replacement. It's a lot easier to find high quality 10w-30 than straight 30, and thats why I go with 10w-30. I'm fairly certain my lawnmower will outlast me on a steady diet of supertech 10w-30 synthetic changed every 2 years. Generator gets the same every 100 hours and sees 500+ hrs a year.
The Briggs manual now says to still use straight 30 or full synthetic 5W-30. I use 5W-30 syn in mine because that's what I use in all my cars except my wife's Jeep, which calls for 0W-20.
I completely rebuilt my Tecumseh HH120 in my old Bolens a few years ago. From day one and after the rebuild the engine has had SAE 30 in it. It is a very hot running workhorse and I will not run anything else unless I was going to do some winter plowing with it. I would be open to trying 15w-40 during the summer however.
Make sure those valves and guides are in good shape before you button it up.
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I own a few older small engines, and service quite a few for customers. I also grew up around antique garden tractors and small engines. The most common oils used were SAE 30 and HDEO 15w40. My choice the past few years for most small engines old or new has been HDEO 15w40. SuperTech, Rotella, Valvoline, basically any 15w40 that's on sale works great in these engines, and is superior in my opinion to SAE 30. Unless used in the bitter cold (I recommend/use 5w30 in snowblowers) 15w40 is what goes in it.
every engine I own gets 0w-40...not sure why anyone would run anything else.
Originally Posted by car54
Manufacturers these days say a 10w-30 performs just like a straight 30 at operating temps and is a direct replacement. It's a lot easier to find high quality 10w-30 than straight 30, and thats why I go with 10w-30. I'm fairly certain my lawnmower will outlast me on a steady diet of supertech 10w-30 synthetic changed every 2 years. Generator gets the same every 100 hours and sees 500+ hrs a year.
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Quicksilver 25W-40 year round (Mercury Marine 4-stroke oil). One of the stoutest 4 stroke oils out there.
Better in every way that what was available back when that engine was originally assembled 
Originally Posted by DriveHard
every engine I own gets 0w-40...not sure why anyone would run anything else.
Rotella T5 10w30.
+1 for Rotella T5 10W30. ed
Originally Posted by thastinger
Originally Posted by DriveHard
every engine I own gets 0w-40...not sure why anyone would run anything else.