Can you blend synthetic and "real" oil

pjbci · Jun 12, 2013

Yes. I topped it off with synthetic. For what its worth, heres more info. The original engine burned a quart of oil every 100 hrs. Komatsu said that was unacceptable and put a new engine in it. The dealer sent old engine back for examination to the factory. They told me it had a manufacturing defect. The new engine is burning oil at a rate of 1 quart every 150 hrs. Komatsu along with myself are monitoring it closely. I can live with this oil consumption rate if they tell me its normal, but they say it shouldnt use any in 500 hrs (like my deere dzr with 5300hrs on it) so they gave me a new engine. We will see what happens next.

Oil change interval on this machine is 500 hrs, it holds 3 gals, no "break in" procedure is reccomended.

Thank you all for the advice. It saved me an hr this morning by not having to run to the dealer.

Coyote machine · Jun 12, 2013

pjbci said:
Yes. I topped it off with synthetic. For what its worth, heres more info. The original engine burned a quart of oil every 100 hrs. Komatsu said that was unacceptable and put a new engine in it. The dealer sent old engine back for examination to the factory. They told me it had a manufacturing defect. The new engine is burning oil at a rate of 1 quart every 150 hrs. Komatsu along with myself are monitoring it closely. I can live with this oil consumption rate if they tell me its normal, but they say it shouldnt use any in 500 hrs (like my deere dzr with 5300hrs on it) so they gave me a new engine. We will see what happens next.

Oil change interval on this machine is 500 hrs, it holds 3 gals, no "break in" procedure is reccomended.

Thank you all for the advice. It saved me an hr this morning by not having to run to the dealer.

Curious what they said was the defect in the 1st engine?
How many hours are on the new replacement engine? I take it is factory fresh, not a reman?

pjbci · Jun 12, 2013

Coyote machine said:
Curious what they said was the defect in the 1st engine?
How many hours are on the new replacement engine? I take it is factory fresh, not a reman?

They told me it had a micoscopic crack in the block. I think that was total bs because the combustion is contained inside the cylinder liner and head. I still dont believe what they told me but i didnt question it because i got a new engine. Maybe one of you all could explain how a crack in block could let an engine consume oil. I suspected the turbo but there was no oil in the intake.

Yes the new engine was a complete "new" komatsu engine. Not a short block, not a long block, not a reman but a ready to bolt in and run engine. My dealer really went to bat for me to get a new motor instead of a reman.

The new engine is at 162 hrs today. Was 152 this morning when i added a quart to get it back to the "full" mark. Dealer pulled an oil scan to try and determine whats going on.

pjbci · Jun 12, 2013

Oh, one more thing, the old engine blew blue smoke all day. The new one doesnt smoke at all but the oil is going somewhere.

Coyote machine · Jun 12, 2013

pjbci said:
Oh, one more thing, the old engine blew blue smoke all day. The new one doesnt smoke at all but the oil is going somewhere.

Interesting, about the blue smoke, and the fact the new one seems to also be using more than normal oil, so far. What if anything does your dealer or the parent company say about what might happen after you get past the first 500hr mark?
Has anyone with Komatsu seen this problem before on these machines?
Sounds like your dealer is a good one, that's a positive to have going for you at least.

pjbci · Jun 12, 2013

The 500hr mark question. Thats why we ran the original engine to 600 hrs before doing anything about it. Me and the dealer were hoping it would quit after the first 2-300 hrs. It didnt get worse or better.

As far as komatsu having any problems with this engine. They claim no problems with any others. Im kinda inclined to believe it because they replaced the motor instead of just saying that a little oil consumption is normal. Had they of told me that, then i would have just kept right on trucking. And yes i have a good dealer, sometimes it takes a lil pestering but they do whatever i ask of em.

Soundguy · Jun 13, 2013

Coyote machine said:
Did you mean:topping off with synthetic?

actually i think i was thinking of saying 'topping off the dino' but then thought about saying 'topping off with syn' and then mixed the 2 and that's what ya get when brain ain't engaged but fingers are in gear.

pjbci · Jun 13, 2013

Soundguy, i knew what u meant. Thanks

RichardM · Jun 13, 2013

Hi,
I have worked with engine oils for 36 years with ExxonMobil as an application engineer (now retired) and have run thousands of tests on almost all of the engine oils available. The first thing to do is to use the correct API designation recommended by Mnfg. ("S"-for spark ignited and "C" for compression (diesel) ignited). Read the label, its all there, if it isn't don't use it.
Most of the major brands are OK, but the best are synthetics. Of course, I recommend Mobil. Mobil 1 or for commercial use Mobil Delvac 1 (only available from a distributor, but less expensive than Mobil 1).
I use Devac 1 5w40 in everything I own, which includes 7 classic cars, 3 inboard boats 2 Ford trucks, 1 Lincoln, two tractors and the usual assortment of small engines. This,also, includes antique engines (1931 Model A). In new engines these days, synthetics can be used as soon as the factory oil is changed.
(Note some HIPO cars (Corvette) come factory filled. I also use it in Marine (4 cycle, Not 2 cycle) engines.
Advantage of synthetics is low volatility (all non-synthetic oils have some components that will evaporate and contribute to oil consumption). If you want your engine to last as long as possible, or if you don't always catch the change on time, us a good synthetic. (Mobil, ..sorry for the commercial). I have personally conducted tests on a commercial fleet that ran Mobil synthetics for incredible change intervals of 100,000+ miles. (Note: Since some of these engines are designed to use oil, they get a little new oil added. If an engine doesn't use oil, I generally change oil at 2 or 3 times the recommended interval.
OK I'll get off the soapbox.
Dick