Good evening gentlemen, I have a recent new (used) dozer purchase that has started throwing a high crankcase pressure code, it will show code CA555 and CA556 as well as the CA435 code that has been on since I got it about 170 hours ago. When I got it it operated great with no issues except when it blew the aux fuse and shut everything down. I looked at the failure code history and it did overheat 1 time since I got it but that was over 100 hours ago and it was fine up until about 4 hours ago. When it brought on CA556 Crankcase Pressure High Error 2 we brought it to the shop and did a complete service on it. We replaced the KCCV filter and checked for excessive emulsion. The filter did not look too bad. I checked the check valve that returns to the oil pan and it is working properly. The troubleshooting procedure in the shop manual says it could be a defective crankcase sensor or the turbocharger could be bad. Currently it has 4300 hours and it does have a Komatsu Reman tag on the engine block with a manuf date of 2019 so I'm not sure when it was installed. I am getting quite a bit of blowby and I didnt get any when i first bought it. Anyone have any ideas? How do I check the turbocharger? Could it be the KCCV? What gets me is if it did get too hot and hurt some internal components, why did it operate fine for over 100 hours? Thanks in advance! Danny
Hundred hours pretty much on time for rings that have lost there temper to show up with burning of oil . Looks like the lack of compression from soft rings is driving crankcase pressure . You may be able to replace the rings only if the cylinders are alright , will need a hone but thats nothing . There was a post on here while back that had a D7 fire a dip stick across a yard with excess crankcase pressure . Just to check , its crankcase pressure and not engine oil pressure
Yes sir its crankcase pressure. We found that that Turbo was failing and have another one coming in tomorrow or Monday so hopefully that is the root of the problem. Thanks for the reply.
Lets us know how you get on with this , I understand how a leaky seal in a turbo could chew through some oil but not at the same time as building pressure in a crankcase . Unless there is a vent from the crankcase fed into the air system to suck fumes out of there and air is being forced the wrong way . Environmental gear sure can throw up some curly problems
Ok, got the new Turbo installed and have the same issues. Heres what has me puzzled, maybe you can shed some light as to what is going on. At some point a reman engine was installed in this machine. current hours are 4300 hours total Since I got the machine at 4135 hrs the L01 code CA435 (code has been on engine oil pressure switch error) has been on. The machine operated fine up until 4253 when it blew an accessory fuse and shut everything down. After replacing the fuse it operated flawlessly until 4279 hr when it started the CA455 (Crankcase pressure high error1). Then at 4291 code CA556 (Crankcase pressure high error2) came on and derated the engine. Looked up the troubleshooting procedure and it said that our KCCV filter may be clogged so we replaced that and did a complete service. A few hours into working the machine the did the same thing. When starting cold and pulling the oil filler cap off there is a little smoke but no oil, after running for a few minutes there is considerable oil blowby coming out of the oil filler. I checked the check valve in the drain from the KCCV filter to the oil pan, we checked for clogged KCCV piping and replaced the turbo which the only other thing that the troubleshooting procedure says is the engine may be seized? How could it be seized it it is running?? I get it it may need rings but would it start it all of a sudden? Is there a surefire way to tell?
The issue never happened suddenly , it was building and got to a point where it couldn't take it anymore and started throwing crankcase pressure high code . Its showing classic ring failure with excessive blow by and right on cue being 100 hours after over heating . Don't dump the old turbo as I suspect there will be little wrong with it .
If you do pull the motor apart get the heads tested and repair the cooling system as your motor could be the second thats been damaged because of over heating