Blister28 Posted March 6 Share Posted March 6 (edited) Hey guys help would be appreciated! Truck blows coolant vapors out of the blowby and fill tube. It's definitley coolant and not blowby from the rings. Coolant slowly drips out of blowby tube after the vapor condenses enough. We took off the valve cover and oil pan and everything inside looked clean. No sign of coolant in the oil. We then pressurized the cooling system for a couple hours and could see no leakage around the liners or up on the valve train. We bumped the starter a couple times to put the pistons in different positions in the liners but still could see no leak. We have heard maybe an air compressor could cause this? How do we test that? The EGR had been blocked at the exhaust manifold so we are doubting it's the EGR cooler. Engine runs great, no smoke from exhaust. Obviously we are concerned. Any theories? Edited March 6 by Blister28 Quote Link to comment Share on other sites More sharing options...
The Heinz Posted March 6 Share Posted March 6 Was going to suggest EGR cooler, but that apparently won't be a problem for you (Very smart of you). We've seen oil cooler/side cover failures before on both 11 and 13 liters, that could very well be your issue. I also wouldn't discount the possibility of the head gasket leaking, but we rarely see that at all. Quote Link to comment Share on other sites More sharing options...
fjh Posted March 6 Share Posted March 6 14 minutes ago, The Heinz said: Was going to suggest EGR cooler, but that apparently won't be a problem for you (Very smart of you). We've seen oil cooler/side cover failures before on both 11 and 13 liters, that could very well be your issue. I also wouldn't discount the possibility of the head gasket leaking, but we rarely see that at all. Its likley a MP7 ! As stated lots of places for this issue to happen even a turbo has coolant to it! think you'll need to pull the pan to chase that one! 1 Quote Link to comment Share on other sites More sharing options...
mechohaulic Posted March 6 Share Posted March 6 sorry I have to ask !!WHY does a turbo have coolant going through it . ?? another topic shows how old and far behind I am. need to find a Mack fleet close buy to catch up on things. Quote Link to comment Share on other sites More sharing options...
fjh Posted March 6 Share Posted March 6 30 minutes ago, mechohaulic said: sorry I have to ask !!WHY does a turbo have coolant going through it . ?? another topic shows how old and far behind I am. need to find a Mack fleet close buy to catch up on things. Bro most all new vGT turbos have coolant to them think to keep the electrical crap cooler! Just my thought! I’ve been away two years now can’t imagine what has changed since I left! Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 6 Share Posted March 6 now he's gonna ask what a VGT is.. Quote Link to comment Share on other sites More sharing options...
fjh Posted March 6 Share Posted March 6 5 minutes ago, Joey Mack said: now he's gonna ask what a VGT is.. That’s fine! We’re all getting old! Buddy! 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 6 Share Posted March 6 He is a wealth of knowledge.. I pick on him at times to get a laugh.. Quote Link to comment Share on other sites More sharing options...
fjh Posted March 6 Share Posted March 6 Just now, Joey Mack said: He is a wealth of knowledge.. I pick on him at times to get a laugh.. evil! 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 6 Share Posted March 6 Mech, I am quite sure as you read these posts, you shake your head and say "what the hell it this crap".. I find myself doing it, and I dont have as many years in, as you do.. I wish I did more with e-6 and older engines, as well as the trucks they were in, but I came around too late.. Jojo 1 Quote Link to comment Share on other sites More sharing options...
fjh Posted March 6 Share Posted March 6 7 minutes ago, Joey Mack said: Mech, I am quite sure as you read these posts, you shake your head and say "what the hell it this crap".. I find myself doing it, and I dont have as many years in, as you do.. I wish I did more with e-6 and older engines, as well as the trucks they were in, but I came around too late.. Jojo You done good Joey! Not much changed just the addition of the drive by wire! The mechanical is the same! What I hated the most was the change to the bolt on cam gear! To sweat on! Dumb! Added insult to injury when having to do a cam job in the bush! Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 6 Share Posted March 6 so true, I just did an E-Tech cam 2 weeks ago.. I had to wait for a new cam key before I could put the cam in, so therefore, I couldnt do any lifter work, or install the rockers and jakes.. to save time.. Quote Link to comment Share on other sites More sharing options...
fjh Posted March 6 Share Posted March 6 That was the key guy I was talking about in the other post 😂 yuo we’re hatin that parts dude!😃 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 6 Share Posted March 6 😥 yep... now I remember.. I dont hate him,, just the crappy training.. You got me.. 1 Quote Link to comment Share on other sites More sharing options...
Blister28 Posted March 7 Author Share Posted March 7 So if it was a turbo wouldn't I get white smoke blowing from exhaust? coolant would leak into the exhaust then correct? how would I test if it is the turbo? It runs clean and has no smoke from exhaust. As stated before we dropped the pan and pressure tested it for two hours with no signs of coolant. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 7 Share Posted March 7 how often and how much coolant do you add to the tank? have you pulled the top off the CCV to see if its got 'mayo' in it? Quote Link to comment Share on other sites More sharing options...
Blister28 Posted March 7 Author Share Posted March 7 We maybe add a gallon of coolant every two weeks. Yes we took the cover off and the valve train is squeaky clean. No Mayonnaise. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 7 Share Posted March 7 so the CCV is clean as well? no mayo........ I wonder if the air compressor is bad and passing coolant into the crankcase? Quote Link to comment Share on other sites More sharing options...
Blister28 Posted March 7 Author Share Posted March 7 Ive heard that before it might be the compressor. But how would I go about checking that? Where would the coolant enter the crank case if it were doing that? the actual crank case breather has slow coolant drips coming out of the overflow tube as well as vapor. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 7 Share Posted March 7 coolant can pass through an air compressor that has a blown head gasket. no different than an engine.. unfortunately, if you bypass the compressor cooling lines for too long you risk more damage to it. so, in the morning after sitting over night, have you loosened the oil pan plug to see if coolant runs out around the plug ? does it blow mist/steam right away or does it need to warm up first? Heck??? does the compressor look like its old and crappy? does it build air pressure good? Quote Link to comment Share on other sites More sharing options...
Blister28 Posted March 7 Author Share Posted March 7 Ive drained the oil and have seen no coolant coming out of the threads of the oil pan or at all. Compressor was replaced by us two years ago. It seems to build pressure ok. The steam mostly come out when its under load and its in PTO. When it's idling out of PTO it's not as bad. (This is a concrete pump truck fyi) Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted March 7 Share Posted March 7 ok,, I dont have enough knowledge on MRU concrete pumpers. I assume with an Allison transmission, with its own cooling system, and cooler.. Is it possible that there is a leak in that system? the tube you showed in the picture was new to me, so I may not have enough knowledge to help you.. grabbin' at straws, and it s bedtime.. Jojo Quote Link to comment Share on other sites More sharing options...
The Heinz Posted March 7 Share Posted March 7 I completely forgot that the air compressor has coolant lines running to and from, goes to show I'm not that experienced! I don't recall that happening to any trucks in the shop, but we've had a bad air compressor that got misdiagnosed into an entire short block R&R... I'll chime out for now unless someone needs some help with parts... Quote Link to comment Share on other sites More sharing options...
fjh Posted March 7 Share Posted March 7 By what all has been said here so far My Guess is EGR Cooler or turbo! what I Think your seeing is exhaust gasses passed by the turbo seals and a small coolant leak there as well! Get an oil sample to start with ! And move on from there in my opinion! It gets worse as the load is applied There is a small amount of boost at idle for EGR purposes accounts for the steady wisp while idling! Oil sample then grab a straw! Pull the pan and pressure test over nite Problem with MP is (for lack of a better term is the butrus plate) it will make it hard to pin point where the coolant is coming from! Or Last resort Get out the parts canon and start shooting parts at it starting with the cheap EGR cooler then the turbo Don't recommend this However............... Note ! Usually ! If it were an EGR cooler there would be mass flow codes! 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.