changing oil types

[daugen]

On a 25 year old clean running 1000 hour Mitsu 25hp in a Case IH 255, am I being dumb by draining the black dino oil in it and replacing it with 10W/30 Mobil 1?

Pretty sure it will clean it out, which is likely needed, so I'm watching the oil color carefully and will change it out after not a lot of hours. But to what oil?
The tractor is not used in the winter, but will be in an open covered shed.
Do I have to stay with conventional oil because of the old bugaboo about leaking seals? Because I will use this tractor for August field mowing, I'm thinking that perhaps the next oil change should be to 10W/40.
From an awful lot of posts I've read in multiple forums, it seems like whatever viscosity, within reason, one picks works as long as it's synthetic.
I've owned Detroit Diesels in the past so I'm used to hunting down strange oil, but do I need to? Thanks very much. Drew

 

[JimRB]

Is the Mobil 1 a diesel rated oil? I thought the Truck and SUV or Delvac 1 were their diesel rated oils. Oil color does not tell you a lot unless of course you do not start the tractor. My JD Yanmar engine oil looks clean after a few hours of running. The oil in my VW TDI is black as a moonless night after running 5 minutes. Well actually blacker than that as the stars really light up the night.

 

[daugen]

Jim, thank you. No, car Mob 1, but I wasn't planning on having it in there for long, just to clean out 25 years of deposits. I've heard suggestions of 15W/40 synthetic Rotella, which seems like a good solution to me. But perhaps I should stick with "plain" Rotella, which I already use in 30W for some older Gravely equipment. And don't worry, I won't be staying up tonight watching my tractor oil to see if it will change color, by star light or not...

 

[Diamondpilot]

I would not do this. Just use standard diesel rated oil only.

Black is a good thing in a diesel. It means its carrying away the carbon deposits. If it were me I would change the oil every 50 hours once a year with a quality oil like Delo 400, Devac 1300, or Rotella and just let it be.

Just make sure whatever you use its Diesel Rated....


Chris

 

[gengine]

Look at the sae rating on the oil bottle. The CI-4 or the CJ-whatever ratings. The "c" is for combustion engines. The "s" is for spark engines. The difference is the detergents and additives. Diesel had different engine harming stuff in the burnt fuel, that very little, but some does slip past the rings and into the oil. The detergents and additives in the oil are specifically engineered to clean your motor. Most diesels, as soon as you change the oil and start the motor, the oil is again black. I don't think running the gas engine oil will hurt anything if it's in there a short time, but I don't think you want to run it past 50 hours or so. I would be worried about build up.

 

[daugen]

thanks guys. I think I'll run the tractor for a day, digging my first post holes for a big garden planned, and then change out to diesel rated Rotella or similar. No high rpm or load until I do. I appreciate the feedback; I think I was being a bit lazy and using what I had on the shelf. No more Mobil 1 btw; Napa has car synthetic on sale for some time now locally for 3.50 a qt. And Valvoline is six bucks; why has Mobil 1 gotten so expensive? No wonder Mobil is making so much money...but having used it for over thirty years, I draw the line when it went over seven bucks a quart. I'm OCD enough about maintenance that the oil never stays in that long anyway, and I always put a new Wix filter in when I change.
So... I stand corrected, and thank you; that's why these forums are so helpful.
Drew

 

[90cummins]

If it was me I would change the oil & filter now and fill with any quality 15w40 & run it. I would check the dipstick to maintain level but more importantly to check the color & consistancy.
Change the oil & filter reguardless of hours if it becomes excessively black & sludgely as this is a sign the oil is doing it's job.
If the engine was neglected the oil will clean it up but you do not want excessive deposits to plug the oil pickup screen as DUMUSH had happen to his new to him Yanmar.
You can read his post with photos in the Yanmar forum titled 336d-started-knocking.

996

 

[Diamondpilot]

thanks guys. I think I'll run the tractor for a day, digging my first post holes for a big garden planned, and then change out to diesel rated Rotella or similar. No high rpm or load until I do. I appreciate the feedback; I think I was being a bit lazy and using what I had on the shelf. No more Mobil 1 btw; Napa has car synthetic on sale for some time now locally for 3.50 a qt. And Valvoline is six bucks; why has Mobil 1 gotten so expensive? No wonder Mobil is making so much money...but having used it for over thirty years, I draw the line when it went over seven bucks a quart. I'm OCD enough about maintenance that the oil never stays in that long anyway, and I always put a new Wix filter in when I change.
So... I stand corrected, and thank you; that's why these forums are so helpful.
Drew

Its all where you buy it. I got Peak Full Synthetic at Pep Boys for $18 in a 5 quart jug with a Fram Filter. Say the filter is $3 thats $3 per qt.

Same is true with a bunch of Castrol Syntec I just bought at Advanced Auto. 5 qt jug and a KN filter for $25. The KN filter is about $9 so that puts it right at the $3 per qt price point also or a little more.

My WalMart has Mobil 1 always for $25 in the 5 qt jug so $5 per qt.

I have bought over 100 5 qt oil changes on special since Jan 1st this year so I will be all stocked up. This will last me about a year. Oil prices are only going to go up. Best deal around here was Orilley. They have the Valvoline Next Gen with filter for $19.99 with a $20 mail in rebate. So ends up free. I also just got 10 4 qt jugs of Valvoline Blue 15W40 diesel oil for $8 each after rebate at TSC. It was on sale for $12 with a $4 per gallon rebate.

Watch the adds. I am in each store, TSC, Menards, Rural King, Advanced, Napa, Orilley, Auto Zone, Pep Boy, each and every week. Some times multiples.

I do the same with Anti-Freeze. I use about 100 gallons of it a year also. I watch the sales then buy it up. I never see RV Anti-Freeze on sale. Best I can do on it is maybe $2.75 per gallon. I use a lot of that stuff also.

Chris