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Synthetic Oil?


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  #1  
Old 05-20-2009, 07:25:52 AM
Stu Stu is offline
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Default Synthetic Oil?

Billy,Gunny,BT.
Gentelmen, Whats your opinions on the use of synthetic oil (10-40) royal purple,in a DJC 9kw. Its a post Ike purchase for emergency use and the sheer joy of smoking out the block on occasion! thanks Stu
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Old 05-20-2009, 08:13:27 AM
jwrape jwrape is offline
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Default Re: Synthetic Oil?

The only issue I've ever had with synthetic oils is that sometimes it burns a little more than regular oils if your rings or seals are worn but other than that go for it. I'm running a synthetic mix in my 6.5kw now. It's that Max life oil. But I run 20w50 for the thickness to try to cut down on the oil burning.
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Old 05-20-2009, 08:35:46 AM
K D Redd K D Redd is offline
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Default Re: Synthetic Oil?

Being your generator is a Diesel unit, does the oil have diesel specs? If so I see no problem. I run 10W-30 Mobile One in ALL of My gasoline and LP fueled unit all of my lawn maintenance equipment without problems.

Kent
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Old 05-20-2009, 11:55:09 AM
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Talking Re: Synthetic Oil?

I know of no REAL problem running Synthetic LubeOil, in Diesel Engines as a general rule. With a "Scream'en Jimmy, however, since it IS going to have Oil Leaks, and you can almost never get them to stop leaking, an expensive LubeOil may cost you a bit more than a good grade natural LubeOil over time. The only other issue you might run into is if you start using a MultiGrade LubeOil in a Jimmy that has extremely worn Rings. This is a prescription for "LubeOil Runaway" (If you have ever experienced this, you know what I mean) where the engine starts burning LubeOil rather than fuel by sucking it up past the rings. The Governor has no control and it will wind up untill it flies apart, UNLESS you shut off the Air Intake to the Blower. MultiGrades tend to enhance this effect. This is why Jimmy's normally use thicker LubeOil, (40Wt rather than 30Wt) than their 4 Stroke Cousins. Helps keep the LubeOil in the Pan, and not the Combustion Chamber.....
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Old 05-20-2009, 07:39:18 PM
Gunny Gunny is offline
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Default Re: Synthetic Oil?

Not all synthetic oils are formulated for use in a diesel engine. Look to the API classification, letters like SJ, SH,CF-4. Generally the S letters go in spark ignition engines and the C stuff goes in compression ignition engines (diesels).

I think that you do well to use a good quality dino oil such as Shell Rotella T or something similar in 15W40 in that engine.

The synthetic I'd use in the gasoline or dry fueled air cooled engines because of their resistance to thermal break down.

By the way, I run that Royal Purple in my motorcycle. Seems to do OK, turns dark when it gets old. Don't notice any increase in power or fule mileage over anything else I've used, might use Mobil 1 next oil chnage.

Probably more important to use a good quality oil and change it regularly rather than any special oil.
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Old 05-20-2009, 08:47:52 PM
Wayne 440 Wayne 440 is online now
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Default Re: Synthetic Oil?

You didn't ask me, but +1 for 15w40 Rotella T. I use it in every 4 stroke engine I own, from the lawnmower on up. You can buy it just about anywhere that sells oil.
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Old 05-21-2009, 06:17:08 AM
Stu Stu is offline
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Default Re: Synthetic Oil?

Thanks everyone, When in doubt,,go by the Manual.
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Old 05-21-2009, 06:33:27 PM
pegasuspinto pegasuspinto is offline
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Default Re: Synthetic Oil?

DD DEMANDS that straight 40w be used in their 2 strokes, period. The bottle should say Detroit Diesel on the back somewhere. 30W is a distant second for the 2 strokes, and they say if you live somewhere in the subartic and only run your engine for a short time, and it never comes up to temp, 10-30 is OK. If it's going to run long enough to get up to temp, and it's -100 out, they are pretty plain about it, 40W oil and a good block/oil heater, some ether and a good battery. It's possible that other oils may work, but DD isn't going to do the work to re-certify new oils on an 'obsolete' engine. My 2-71 will start with some cranking even below freezing. I dunno what people REALLY do in the cold, far north when you can take bottles of 40 weight, cut the container off, and stack the oil inside like bricks, but in hurricane land, 40w would be the way to go.

Robert
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Old 05-23-2009, 08:04:14 PM
Bob-C Bob-C is offline
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Default Re: Synthetic Oil?

I have been using 15w40 from NAPA for the last 22 years in my 8V92 TAs. The newest one is in a 2002 truck.. It may be one of the last 92 series engine sold in a fire truck in the US. The oil is CI-4 rated. The engines are low hour, and equiped with heaters even though we are in South Florida.
We have never had any problems with this oil.
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Old 05-24-2009, 11:00:18 PM
K D Redd K D Redd is offline
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Default Re: Synthetic Oil?

A trucker friend of mine said you could get-away with a multigrade oils in a turdoed DD because you had more positive pressure in the cylinders because of the turbo. Miltigrades have a tendancy to cause run-aways. BE SURE your trap door in the BLOWER INTAKE works if you must use multigrade oil. That said as said by others above in this post strait 40 is the oil of choice for a DD 2 stroke diesel.. I have a Detroit Diesel Engines V-71 Highway Vehical Service Manual 6SE228 (Rev. 4/84) Section 13.3 Page 5 speaks of oils for a DD. The uses of multigrade oils is ONLY recommended ffor the 8.2 Liter 4-Cycles.

Kent
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Old 05-25-2009, 12:51:27 AM
Gunny Gunny is offline
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Default Re: Synthetic Oil?

Quote:
Originally Posted by Bob-C View Post
I have been using 15w40 from NAPA for the last 22 years in my 8V92 TAs. The newest one is in a 2002 truck.. It may be one of the last 92 series engine sold in a fire truck in the US. The oil is CI-4 rated. The engines are low hour, and equiped with heaters even though we are in South Florida.
We have never had any problems with this oil.
Read your engine manual. Bet you lunch that it'll mention that you should use SAE 40 oil in that engine and also give the API spec to use.

Just because you've used 15W40 without a problem doesn't mean it the right thing to do. A lot of folks do run 15W40 in those 2 strokes, mostly out of not knowing what they should be using, without an issue, however, one day you may wish you had.
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Old 05-25-2009, 01:03:41 AM
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Talking Re: Synthetic Oil?

Just a note here, on the Run-Away senerio for DD's (Scream'en Jimmy's)..... This only becomes an issue IF, or, WHEN, the Rings get badly worn, OR you have an Oil Seal in the Blower fail. It really isn't a problem, unless one of these two things, happens. If it does happen to you, the only way to shut down the engine is to cut off the Air going into the Blower. This is usually accomplished by the Air Dam CutOff Door, If you engine has one fitted. If not, a piece of Plywood, Rags, a Coat, or anything else, to put across the Air Intake and shut off the Air... because the engine IS going to fly apart, and do so like a HAND Grenade.....
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Old 06-09-2009, 10:42:24 PM
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Default Re: Synthetic Oil?

I love API Group IV synthetic oils (ie "real" synthetic, not severely hydrotreated and called synthetic). TTBOMK, Royal Purple is a Group IV base stock oil.

However, there can be issues in older engines around seals compatibility. Generally, pre-1980 would be a reasonable demarcation -- maybe.

Older seal materials are designed with old oils in mind. Old oils had a lot of crap in them, compared to modern oils. The seals depended on this crap to provide part of the seal build-up. This is esp. true of the older automotive rear main seal "rope" seals.

You *might* have increased seals leakage when switching to a synth oil.

If the seals have been replaced with more modern equivalents, this shouldn't be a problem.

Oil burning: when comparing viscosity to viscosity, synth oils always have a higher flash point and much lower evaporation rate -- yes, lube oils evaporate, at the temps they run. So synth oils can reduce oil consumption through burning -- if the same viscosity is used as for petro oil.

Both camps have their adherents. I try not to make it a religion. Keep the oil clean, that's good enough for me. But, I too run synth oil in everything I own.
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Old 06-11-2009, 02:36:31 PM
mcarbaugh mcarbaugh is offline
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Default Re: Synthetic Oil?

Hi Stu,

I am in North East Houston and would love to help you work on your onan. I just got done a total restore on my 4.0CCK. After I tore it down I could not figure out how it ran with all the rod damage. All I can say is MADE in USA!
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