I should have said it different in the previous post. The price of regular oil is getting closer to the price of synthetic.
I can't say I've heard that one. There may be a benifit, thats hard to prove. But we have a L10 in a 1988 skidder with over 8300 hours on the engine and have never done the turbo.
Oil breaking down due to lack of maintance would shorten life IMO. turbos were Running long lives for a lot of years before synthetic oil was around.
Here is the number one reason you should use Synthetic oil if your engine has a turbo: The bearing in a turbo is a floating bearing that floats on a layer of oil. This oil is fed from the oil pump though the oil filter and into the bearing. When you shut down the engine, the heat from the exhaust side migrates through the entire turbo housing raising the temperature. The flow of oil is also stopped and a drop or two of oil remains at the orriffice (opening that the oil flows through). Crude base oil burns or Cokes from the heat. Eventualy this coking builds up around the orriffice and stpos the flow of oil, leading to turbo seize and a$3,000. repair bill. Synthetic oil does not coke due to it's high temp resistance to coking or burning. WARNING; you must use a synthetic oil that is blended for diesel engines. NOT ALL synthetics are diesel compliant! If you prefer to use a crude base oil, you can install an engine "Pre Luber". This is a pump that starts after you shut the engine down and continues oil flow to your turbo until it cools down. You can also use it to aviod dry starts. This pump will build 50 lbs. of oil pressure and if your equipment sits for long periods it is a great way to increase the life of your engine. Anyone have a comment on dry starting engines?????
Thats good infofmation and makes sence. They recomend to idle at a minute or two before shutting down. Im sure the torbo still gets hotter after shutdown as does the rest of the engine.I recently rebuilt my lx865. The turbo had a lot of carbon Buildup inside. I took it appart and cleaned everything. What I thought was carbon from the exhaust could have been cooked oil built up. They dont recomend taking a turbo apart but it was that or a new one. The book shows it being rebuildable. the dealer told me they dont do that,they replace them. They dont have mechanics just part changers.My turbo is doing fine at 85 hours since the cleaning.I would like to keep it clean. I dont use offroad fuel, sorry Im running on.
Go to: www.pre-luber.com that is where I got mine for my Dodge Ram 2500. I don't drive my truck everyday, sometimes it sits for a month so B-4 I start it I run the pre-luber to build oil pressure, then start it. OOPS, there is something I forgot to mention about ALL SYNTHETIC lubricants; They will clean your system, so if you have been running crude based oils in your engine or hydraulic system, drain half the oil out and fill with synthetic oil. Run that for a few weeks and drain and refill with synthetic. If you are overdue for an oil change than drain it all out and run the synthetic about half the change interval and refill with synthetic again. You can extend your interval between changes when using synthetics, depending on the conditions. I know some guys that will extend a 3,500 mile interval to 5000. Joe
I have a 3500 series ram pickup with a pyro meter. It is surprizing how quick the guage drops when you get your foot off the throttle. But i thinK the most important thing is a minimum 1 minute cool down for a engine that was lightly loaded in the last few minutes of operation. if it was loaded heavy, a 5 minute cool down is more in order. This gives the heat time to transfer from the inside to out.
The reason I bought my Pre-luber. I was fueling up and guy hauling truck caps on a trailer pulled in. He had a Dodge with a Cummins just like mine. We struck up a conversation about the noise under the hood when he shut his engine off. He showed me the pre-luber and then told me to look at the miles on the odometer. 878,000. miles and the engine and turbo had never been apart. He said when he gets 1million miles on it, he is going to sell it to his neighbor. Synthetic oil and a pre-luber, sold me on both!
I use Lucas oil additive in my desiel engines to help. I had a duetz desiel in my trencher that had set for about 3-4months and i was going to do a head gasket, i had lucas in my oil and when we pulled the head the lucas was still on the rockers i would think that would help in the dry start-up. I know when you use it for the first time the engine will use the lucas you put in, for instance if you use half a quart you run it the first time it will show a half quart low the next check, top it off and it will be fine from then on. Even at the next oil change it will not use any the next time. I think it just stays in the upper part of the motor and will not check. It works for me i don't know about anyone else. My uncle runs a over the road truck and swears buy it. He said normaly most turn the mains at about 750,000 miles and he has had his done and they always ask how many miles he has on it, the machanic always thinks it only has 500,000 or less, and want to know why they are doing the bearings. just my 2 cents. Brent.
I agree with ken, you can't argue with fact, big rigs have logged zillions of miles on good old dinosaur oil, long before synthetic appeared. if synthetic was really that good!, dinosaur oil would be no more....
Perry I think from your responce you may not really know what synthetic oil is all about , maybe it's really a myth and I am not right in what I believe , but here goes it's is not oil made by man , it is the same old melted down dinosaurs juice like you call it , the process that makes it synthetic goes soethig like this , I don't remember the actual numbers but think it's about 10 % for say you have 1,000,000 A-1 molicules in a gallon of oil and 9,000,000 of lesser quality B , C and D molicules , they refine the oil to remove all the A-1 quaility and that what synthetic is , I wonder who is getting all the lesser quality stuff that is left over -----idle up and idle down yoyr turbo and you will be ok , wide open starts and hot shut downs are the killer
I didn't know that, I did assume it was man made...Thanks.
where does the air go to spin a turbo when being towed? it the pipe through the turbo into a cyl till it hits a closed valve.....how would it go out??? no flow=no spin.....
Just couple of links on synthetic oil to read when your bored.
Sterlclan - my thoughts exactly, but others swear it happens?
I could see a slight rocking due to movement on the trailer (or boat) but a full spin I think not. Ive towed many machines both with taped exhaust and open haven't had any trouble.......yet. I would think debris getting in through the pipe would be a larger concern,as far as oil let it idle to lower the temp before shut down and itll be fine....
The theory is not that the turbo spools up while towing but just that it turns without oil, doing damage to the bearings, then when its started the bearing are really dry when the turbo spools up. It may have been a coincedence the one on the 740 skidder failed when it did, but with only 1200 hours on the machine, it ran fine onto the float, when we went to unload it it smoked terribly black and would barely pull itself. When we pulled the air filters to see what was happening we found pieces of the compressor turbine inside the air filter housing on the clean side of the filters. Apaently it crashed right after startup.
