colemen 3500 watt generator

[JR]

i have a 3500 watt colemen generator powered by a 5.5 hp ohv tecunseh
I broke it in on plain old 30hd dump that at five hours
have ran 15w40 or 30hd since new changed out ever year (20 hours)
I currently have Mobil 1 5w30 truck and suv sl-rated with 20-some hours on it
I am using this generator now to power my pole barn
I on average put between 2 and 10 hours a day on it when i use it now

what oil would you use and how long would be ok for extended drains?
i was thinking that i might use amsoil 15w40 since i have a few quarts laying around or is there better oils out there?
i was considering there oils as choices:
Mobil 1 15w-50, Mobil 1 Turbo Diesel Truck 5w40, 20w-50 motorcycle
rotella t syn 5w-40, syn-blend 10w30
or if you think extending oil drains aint good:
15w-40 syn-blend mystic or wolfshead
chevron farm-bulk 15w40, 30wt
hdeo 15w40, 30wt, 40wt

thank you
kc

 

[fsskier]

I suspect that this is an air cooled engine, with little thermostatic temperature control??

Perhaps any of the 15W40's in the summer, continuing with the 5W30 Mobil 1 for winter may give you a reasonably constant viscosity, and some chance of starting on cold winter days??

 

[gd9704]

My 2 cents:

If it were mine, I'd first install a Drainzit for easier oil changes. Makes oil changes fast and nearly mess free.

For small air-cooled engines with no oil filter, I prefer to stick with the suggested change intervals, regardless of the type of oil used.

While synthetics are good because they don't cook at high temps, the lack of an oil filter means there's garbage floating around in the oil, wearing the engine.

In my gensets, I use a HD30 oil in the summer (because I have lots of it) and Mobil 1 10w30 in the winter.

I have 2 gensets, and I've noticed a few differences in their characteristics....I have Craftsman 3,250 watt unit (made by Generac in 1996) that has a 6.5hp ohv engine. It calls for oil changes at 25 hours. When it runs, the oil gets HOT. The generator gets pretty hot as well when it has a load on it.

The other unit is a Honda EB5000 made last year. It has a 11hp engine. The manual says change the oil at 100 hours. For me, that seems like a very long time for an air-cooled engine with no oil filter. However, you run this engine with a load for an hour, and the oil is only warm. The generator unit has a huge cooling fan that really moves some air, and the result is that aside from the exhaust, this unit barely breaks a sweat. Hence the 100 hour oil change interval?

Sorry so wordy, but I love gensets and maintaining them!

Greg

 

[Cujet]

Mobil 1 5W-40 Turbo Diesel Truck is a very robust oil that will work in both cold and warm climates. It contains plenty of ZDDP, essential for long air cooled, flat tappet, engine life. It also has a high TBN to combat acids and will work exceptionally well in extended drain intervals. In summertime, Mobil 1 15W-50 is unbeatable.

Common engine oils are not as robust as diesel engine oils. Nor do they contain as much ZDDP. Your choice of a diesel engine oil is a good one.

 

[JTK]

I've got the 7hp version of that Tecumseh OHV on my snowblower. It's a great engine. Real easy on fuel, starts w/ barely a pull and doesn't rattle itself to pcs like most Tecumsehs. Like Cujet says, for all year usage, I'd go with a 5w40 HDEO. Shell Rotella-T, Mobil, etc.

Joel

 

[JimPghPA]

Because you use it on a regular basis you should consider a K&N air filter along with the clean and oil kit. Pep-boys can order it for you. Because these small engines use a small filter the clean and oil kit will last a long time. Call K&N to get the part no. Clean it every 100 hours.

Because you use it on a regular basis you could chose the oil that would be best for the season. If it were mine for winter I would consider GC, or Shell Rotella T6 5W-40, or Mobil 1 Turbo Diesel Truck 5W-40. I would prefer GC for coldest temperatures, but any of these would work. Shell Rotella is probably the lowest cost, especially by the gallon.

For mild temperatures I would consider the same oils, + Shell Rotella T5 15w40 (even lower cost than 6T), and mono weight Shell Rotella T 30wt, mono weight Pennzoil HD 30, or mono weight Castrol HD 30, or Mobil 1 15W-50.

For hot weather Mobil 1 15W-50.

I would also get in touch with the local Amsoil rep and get some foaming carb cleaner. About every 100 hours just before an oil change, use it, and run the engine for about 5 minutes to get it out of the carb and then change the oil. Also, put a new sparkplug in after that, carb cleaners foul plugs.

If you have a season that you do not use it be sure to either drain the tank, or add Sta-Bil to the gas, and then turn off the gas and run the carb dry.

I would change the oil every 25 hours with Shell Rotella, and every 50 hours with GC, or Mobil 1 15W-50.

 

[JimPghPA]

BTW I saw something that said Rotella 10w30 does not have JASO-MA. You might want to think twice about using it for a generator.

 

[JimPghPA]

According to a service teck I spoke with "Coleman gensets generally come with the governor set to too high of an rpm". He said extra engine speed is tough on these engines, and to get long life from them you should adjust them to exactly 3600 RPM.

He told me to run it for a few hours to break it in. Then at half load (I used resistive heaters) adjust the RPM's to exactly 3600 for exactly 60 HZ output. There are three ways you can do this: 1) Use a frequency meter and set 120 AC output to 60 HZ. 2) Use a tack on the engine. 3)Use a 120 volt AC analog clock and compare it to a battery powered clock or watch. The 120 AC clock when ran from a generator will be slow, right on, or fast depending on the frequency output of the generator.

If the engine ever hunts in throttle (goes up and down and does not remain steady) adjust the governor throttle response spring by changing the leverage applied to it.