So far I have about 15-20 hrs on this new to me backhoe. This week I dug a 400' ditch, buried (1) road pipe. I have made sure to check fluids everyday and even replaced the rear diff fluid with the additive which quieted the brakes. I have checked for blow by from the vent hose down by the pan (it was slightly wet but no smoke. I opened the oil fill cap and no smoke or spitting oil... The only time I have any smoke from the pipe is when just getting on accelerator (black puff) Yesterday I finished up for the day after digging through a little rough spot in the ditch (granite/petrified clay). I left it idling while my wife and I went to look at the progress. It idled for about 10-15 minutes at low rpm and started sending a continuous line of light blue smoke. Does that sound normal/bad? Are there any breather lines or filters that could get clogged or need service? Thanks for any help Daniel
Serial Number please so the correct technical information can be located..... Basics. You talk about fluid levels, etc, but no mention of any recent air cleaner service. Have you changed the elements..? If it was mine I would not be idling it more than 5 minutes let alone 10-15.
Yes, I also changed the inner and outer air cleaner. Today I went back and checked the oil. It was about 1 quart over the max but did not smell like gas or have any signs of water. I removed the extra oil and got it back down to exactly the max mark. I ran it for about an hour digging out a bank and ditch this am and No smoke and seems fine...? Is it bad to et one idle longer than 5 minutes? I usually let it warm up for 7-10 minutes before working it and then cool down for 5 minutes before shutting it off at the end of the day. Partial serial is BLN5489. It is a 2002 420D IT 4WD TLB Thanks again, Daniel
Idling to warm up after the engine is started from cold in low ambient temperatures is one thing, idling before shutdown is something completely different IMHO. Your fumes disposal setup should look like this. All you can do is make sure the hose & connections are clean & unobstructed.
So ...don't let it idle to cool down for 5 minutes? I thought I read that letting it idle and cool down was a help in cooling down opposed to just turning it off hot? Please let me know as I don't want to damage it.
I would idle it for no more than a couple of minutes before shutting down if it was mine. My comment above was related to your OP where you said the machine was idling for 10-15 minutes and began to smoke. I commented that IMHO 10-15 minutes was too long, 5 minutes would be more than sufficient.
Thanks for clarifying. I'll make sure and not let it idle too long.
The cooling down is mostly for the turbo, if you get your turbo glowing translucent like some people here, then you don't want to shut it off with a white hot turbo, it's bad for the turbo bearings. So if you just climbed a hill with everything the motor had, you want to let it idle 5 minutes. If you're digging with the backhoe, it's pretty hard to load the engine much, so shut it off the second your hand leaves the levers, no problem. Read the operators manual for warming up. I doubt it says to warm up 7-10 minutes. 30 seconds is all they get if it's cold, well below freezing that is. Now, working it slowly and very carefully is always a good idea until fully warmed up. They warm up faster running than idling. The idling engine won't warm up, it will help the hydraulics, but only the parts moving. And keep a close eye on that oil level. If it goes up again you have a big problem.
Just to add to Delmer's comment, warm up should be at low loads and low engine speed. The engine oil filter base has a filter bypass valve in it to prevent the filter media from rupturing under high pressure events. If the engine is operated at high RPM, the oil pump will be trying to move a lot of cold, thick oil. The oil filter paper media can only handle so much restriction before disintegrating so the filter bypass will open allowing thick, cold and unfiltered engine oil downstream where only clean oil should be. For hot shut down, no less than three minutes for head temperatures to balance. The exhaust valve is extremely hot and the intake is "cool" so you want them to equalize before shut down. Obviously, you also want the turbo to spool down so it doesn't carbon what oil is in it and scorch the bearings.
I think a lot depends on what you have been doing immediately prior to shutdown. If the machine has been run hard with all systems up to or close to the red line, then a couple of minutes to let everything cool down a tad is a very good idea. However if the machine hasn't been worked hard prior to shutdown you can literally turn the key off 30 seconds after the RPM reaches low idle. There's no hard and fast rule, but if you're thinking about system temperatures you will always pretty much do the right thing.
I was able to read some of the owners manual, although rotted. It said; above 36F to hold down the gas pedal and crank. Let idle for 5 minutes. Then reading along... it said to let idle at half throttle for 5 minutes. Cool down was basically let idle for 3-5 minutes before turning off so temps can balance out... I've been doing the above and varying minutes for cool down/warm up depending upon how hot the temps are and what kind of work I've been doing. So far, I've had no more smoke when idling since I changed the oil and filter. initially, I had an extra quart.5 in the engine. So far, since the oil an filter The level has not changed Thanks for the help here.
Best of luck to you NCMan. Good discussion!