Small engine, PCMO or HDEO?

[supercity]

For a small stationary engine, like a diesel generator, or petrol for that matter would you recommend a HDEO or PCMO or a small engine lawn mower type oil?

Most of these engines usually spec only a CC/CD or SF so can be met with just about anything.

 

[DirtyMoe21]

I would run a synthetic PCMO of your choice. I've been running Mobil 1 and Ultra in my Honda with no issues. Most spec 5w30 or 10w30.

 

[earlyre]

there seem to be 2 schools of thought here. (3 if you count "use what the manual says")
1) run what ever you have lying around(even a frankenbrew of leftovers)
2) 15w40 (Which is usually HDEO, Usually)

 

[SwampSurvivor]

Originally Posted By: earlyre
there seem to be 2 schools of thought here. (3 if you count "use what the manual says")
1) run what ever you have lying around(even a frankenbrew of leftovers)
2) 15w40 (Which is usually HDEO, Usually)


I usually do the first. I'm pretty sure the lawnmower has had RT6 in it before. This year it's late 80s Mobil1 10w-30.

 

[IndyIan]

I tend to run RT6 5W40 in anything valuable as its a good year round oil, and whatever is handy in the rest.

 

[Eddie]

I always follow the manufactures recomendation and for my gas engines it is usualy 5w or 10w30

 

[supercity]

Can anyone offer a technical reason why one would be better than another.

 

[440Magnum]

Originally Posted By: IndyIan
I tend to run RT6 5W40 in anything valuable as its a good year round oil, and whatever is handy in the rest.


Same here. Everything from the push mowers to the 30-horse Ferris ZTR gets synthetic 5w40. But I never have to worry about operating them below mid-40s temps.

 

[Dufus2]

Over the years, I have noticed that mowers run better with a SAE30 oil over a multi-grade. But recently, some engines prefer a 10w30 for all seasons. Generators can also run hard when loaded down.

My thought on this comes down to the multi-grade shearing back into a lighter film where a single-grade oil remains constant. If your generator is hard working, why not go with a small engine oil specific to the OEM recommendations.

 

[mrsilv04]

I always use a HDEO if one is available.

Onan recommends 15w-40 for the generator in the motorhome (I use Rotella T 15w-40).

In the Kawasaki powered John Deere Lawn tractors, I use 10w-30 Rotella T (white jug - $12 a gallon).

Here's a picture of under the valve cover of one of the Deere's at 2020 hours, after oil changes every 125 hours with 10w-30 Rotella T. This oil is doing its job, and is doing it well...

 

[fdcg27]

For most of the OPEs I have, that run for maybe a couple of hours at a time, I use whatever is laying around or whatever I've picked up dirt cheap, as long as it's at least a thirty.
For something like a generator, though, especially a diesel one, that might be called to run for many hours at a time, I'd be a little more picky.
For the little gas genny we have, I use T5 10W-30.
T6 5W-40 would also be a good choice.
OTOH, Delcac 1300 15W-40, of which I have a few gallons, would also likely work well.
What I'm saying is that it depends upon how the engine will be used.
I'd use a premium oil in a generator that might be called upon to run for many hours.
If it were a diesel, I'd be sure to use a suitable oil.

 

[FastGame]

IMO if the engine doesn't have cat muffler then an HDEO would be the better choice. JD, Kohler, Briggs oils are HD the last I checked.

I use 10W-30 HDEO.