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d9gdon 01-27-2013 06:57:57 76.1.99.192 Report to Moderator	I've got to work on a JD 6068 engine in a car crusher tomorrow. It started blowing steam out of the blowby tube yesterday after startup. It's got coolant in the oil now. It runs fine and doesn't smoke white or anything. I was planning on pulling the head to see if the head gasket blew or if the head was cracked, but I wanted to run it by the experts here to see if there was anything else to check before I did. The scrap yard has had this thing for several years and it's been sitting for a couple of months. They had just started a new job with it. Started it up and idled it up and after about a minute or two it started doing this. Everyone from the crew to the manager says that it's never been hot or even blown a coolant hose. One thing I did find on an internet search was to check the water pump weephole to make sure it wasn't stopped up and sending coolant into the crankcase. I don't even know if that's possible on this engine, but was gonna check when I get to it. I do have the service manual for it and it's got a troubleshooting guide for coolant in oil, but just lists the common causes like cracked head, head gasket, liner protrusion, etc. Thanks This post was edited by d9gdon at 07:00:42 01/27/13. [Reply]   [No Email]
CPeter 02-09-2013 06:49:19 75.68.16.38 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 06:57:57   I am curious, what happened with this engine? Is it still running? CPeter [Reply]  [No Email]
d9gdon 01-28-2013 11:15:30 184.6.190.86 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 06:57:57   [quote="richardinnz"](quoted from post at 22:24:30 01/27/13) I think I found the problem. This thing has an air compressor mounted on gear drive on the right side of the engine. I'm going to take it off and check the seals before I pull the engine and take the pan off. [Reply]  [No Email]
d9gdon 01-28-2013 18:09:42 76.1.99.192 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-28-2013 11:15:30   No luck. I pressurized the coolant line of the compressor with shop air with the outlet blocked off while I had the bottom cover (pan) off it and saw or heard no leak at all. I found the radiator fins stopped up with old oil and dust. It's a blower fan so evidently something leaked onto it and plugged it up. It's pointing to an overheat situation, but it should have been protected by a high temp kill switch according to mfr. Next step is to pull engine and drop pan to pressurize cooling system. Still could be pinhole in liner because of no corrosion inhibitor as well. [Reply]  [No Email]
Tim S 01-28-2013 19:14:32 75.49.0.238 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-28-2013 18:09:42   If you can pressurize the radiator with a tester that will help prove a liner failure, sounds like where you pressured it up is only the oil cooler... [Reply]  [No Email]
d9gdon 01-29-2013 04:40:22 76.1.99.192 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to Tim S, 01-28-2013 19:14:32   My pressure tester wouldn't fit the radiator cap. I'm going to try to find one today. The air compressor gets its coolant supply from a line that comes out of the water pump thru the compressor and back into the side of the block. I pressured the supply line with the return blocked off to see if the compressor head gasket was blown which would dump coolant in its crankcase and mix with engine oil shared at the gear drive. I need to look in the manual, but is the oil cooler mounted on the side of the block as I didn't see any lines going to the radiator? I worked on a 450C dozer and it's cooler was under the oil filter. I have CTM 104 which I'm calling the service manual. This post was edited by d9gdon at 05:07:30 01/29/13 4 times. [Reply]  [No Email]
d9gdon 01-29-2013 05:21:23 76.1.99.192 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-29-2013 04:40:22   I looked at the oil cooler in the manual. I'll test it first today. Supposed to rain though and this won't fit in the shop right now. [Reply]  [No Email]
d9gdon 02-03-2013 06:38:42 76.1.99.192 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-29-2013 05:21:23   OK, I want to update this and try to get some more help. I pressure tested the oil cooler and the air compressor and they're both good. I wasn't able to find a radiator pressure tester, but it wouldn't have done much good as you can't just jerk the pan off this engine cause it sits in a cradle with supports underneath that are too close. I put everything back together and ran it with the overflow tube in a bucket of water. Had quite a few bubbles at first and then a few more after a couple of minutes, then the bubbles stopped. I let it run for 30 minutes or more while checking for any bubbles, but had none. I noticed in the manual that you're supposed to bleed the system of air when you pull it down as far as I had it, but that was after the fact. I pulled the oil plug on it the next morning and no sign of coolant. I ran it 30 more minutes and no bubbles at all this time. We ran the hydraulics on it to put a load on it too. So I figured that the little bit of water in the oil that I'd found originally (just enough to be noticeable and cause the steam out the blowby) had came from a pretty violent 4" rain that we'd had a couple of weeks ago. I figured that the rain cap had gotten blown up and an exhaust valve was open to the cylinder. We decided to start crushing again on Thursday. As soon as we started putting a load on it, it blew coolant out of the overflow tube but stopped shortly after. It's a little low on coolant in the radiator but runs perfect otherwise with oil and temperature normal. When you add coolant to it, it pushes it back out until it gets down to the same level which is below the bottom of the radiator neck. There is still no sign of coolant in the oil after two days of running. I'm having the crew to check for moisture in the filler cap and to make sure there's no steam coming out of blowby tube as it's out in the country and I've got an urgent miss in another 6068 in an excavator that I was moved to. I'm wondering if combustion is getting underneath a liner flange and pressurizing the radiator causing this? [Reply]  [No Email]
Tim S 02-03-2013 08:51:40 75.60.192.141 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 02-03-2013 06:38:42   "Almost" every time there is a 'Ghosty' amount of blow by steam or water push it's from a failing liner. On a few times I have changed head gaskets at the owners request when this happens and every time I ended up removing the head a second time to preform a complete O/H. The exception to this is the cam shaft driven water pump...which I think is a bad design idea... [Reply]  [No Email]
Tx Jim 02-03-2013 09:47:54 67.142.163.26 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to Tim S, 02-03-2013 08:51:40   Quoting Removed, click Modern View to see Amen. Makes one wonder what the JD engineer was smoking that day when he dreamed up a gear driven water pump. [Reply]  [No Email]
JDGnut 01-27-2013 19:10:11 75.9.56.185 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 06:57:57   As stated above.. Most of the 6.8's have belt driven coolant pumps.. Also check the oil cooler on the lower right front.. Haven't seen too many head gaskets fail on the 6.8's.. Good luck [Reply]  [No Email]
richardinnz 01-27-2013 18:24:30 125.239.160.222 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 06:57:57   Coolant pump on a 6068 is belt driven, mounted low down on the front cover, just has a ring of M6 screws holding it in after you have pulled a hose and water tube. Unless the aluminium housing it is bolted to has corroded out behind it then it would be unlikly this is your problem. Stick the over flow hose in a bottle with water in it, bottom of hose under the water, if you get bubbles when the engine is running you have a failed head gasket, or on a later engine it could also mean a failed EGR cooler. We have been caught out with that one on a 7530 tractor, wierd build because it had a Mexican engine in a Manhiem tractor and not a Saran motor. The engines will also suffer the same old liner troubles if the motor has not had Thermogard (I think this is called Coolgard in some countrys) in the system. There are also plenty of John Deere DTAC solutions about liner protrusion on these engines so beware to check it properley. You really need to get John Deere CTM104 for correct repair specifications. [Reply]  [No Email]
d9gdon 01-28-2013 09:32:01 184.6.190.86 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to richardinnz, 01-27-2013 18:24:30   richardinnz said: (quoted from post at 22:24:30 01/27/13) Coolant pump on a 6068 is belt driven, mounted low down on the front cover, just has a ring of M6 screws holding it in after you have pulled a hose and water tube. Unless the aluminium housing it is bolted to has corroded out behind it then it would be unlikly this is your problem. Stick the over flow hose in a bottle with water in it, bottom of hose under the water, if you get bubbles when the engine is running you have a failed head gasket, or on a later engine it could also mean a failed EGR cooler. We have been caught out with that one on a 7530 tractor, wierd build because it had a Mexican engine in a Manhiem tractor and not a Saran motor. The engines will also suffer the same old liner troubles if the motor has not had Thermogard (I think this is called Coolgard in some countrys) in the system. There are also plenty of John Deere DTAC solutions about liner protrusion on these engines so beware to check it properley. You really need to get John Deere CTM104 for correct repair specifications. Well the water pump doesn't seem to be the problem or the bearings aren't out anyway. It's not looking good as nobody has ever put any Thermogard in it. Gonna have to pull the pan and pressurize it. BTW, it doesn't have the EGR cooler as this machine is probably a 2002 model. I guess by the DTAC solutions you mean service updates along the way on these engines, and CTM 104 is an updated procedure for checking liner protrusion? This post was edited by d9gdon at 09:37:23 01/28/13. [Reply]  [No Email]
Tx Jim 01-28-2013 04:41:03 67.142.163.21 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to richardinnz, 01-27-2013 18:24:30   richardinnz said: (quoted from post at 21:24:30 01/27/13) Coolant pump on a 6068 is belt driven, mounted low down on the front cover, just has a ring of M6 screws holding it in after you have pulled a hose and water tube. Unless the aluminium housing it is bolted to has corroded out behind it then it would be unlikly this is your problem.. Richard Thanks for the heads up. I was unaware that JD went back to a belt driven WP. I always thought it was "DUMB engineering" to have WP seal fail and dump antifreeze in the crankcase.such as my 4255 has done before. If I researched correctly it appears JD uses this type water pump on several different Mannheim/Saran type engines also This post was edited by Tx Jim at 04:43:49 01/28/13. [Reply]  [No Email]
richardinnz 01-28-2013 21:10:50 125.239.162.42 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to Tx Jim, 01-28-2013 04:41:03   Yep, that waterpump went right back to the 6*10 series Manhiem tractors. DTAC is the JD Dealer Technical Assistance Centre, they are damn good, The CTM is the Component Technical Manual, the shop manual that covers the 6068 motor. BTW Manhiem don"t make engines, the 4045 and 6068 come from Saran (France) prefix CD or Mexico prefix PE. I think only the big "grunters" are from Waterloo, the 6090 and 6130, and the old 6081. Unlike the post above we have had our share of head gasket failures on both Saran and Mexican engines, they do not need to overheat, the water level just has to drop a bit, then you can bet your life that 12 to 18 months down the track you are putting a head gasket on the engine. [Reply]  [No Email]
jturbo10 01-27-2013 09:17:38 67.232.120.65 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 06:57:57   Had a similar thing happen to my John Deere 4450 with the 466 engine. You need to immediately drain the oil to get rid of the water in the oil. Has the oil and water emulsified to a beige color with a chalky feel? If so you will need to flush the engine to get the "sludge" out of the engine. As Tim suggested, the best option is to pull the pan to clean it out. I used a cleaning gun with a diesel and ATF solution to clean the top and bottom end to get all the mixture out. After getting most of the oil mixture flushed out, I filled it up with diesel and started it up for about 20-30 seconds to flush the oil journals. Drained the diesel and added fresh cheap oil and a new filter and ran that for a few minutes at idle and drained it. Now I replaced the water pump with a John Deere Reman which in the long run is about as cheap as buying all the parts and having JD dealership doing it. Dealership would only give me a 90 day warranty if they did the work. Cost me about 450-475 dollars to replace the water pump as I put on all new hoses, thermostats, etc. Once done with the pump install I did a pressure check for leaks and then repeated the new oil and filter again and ran for 10-15 minutes at idle and drained again. Will change oil again once hay season starts. Tractors runs great with normal oil pressure and proper temps so it looks like I got it fixed before it did any damage. Lots of money for pump,oil and filters but it sure beats an engine change. [Reply]  [No Email]
Tim S 01-27-2013 09:55:58 75.49.13.105 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to jturbo10, 01-27-2013 09:17:38   When they get all sludged up it's hard to get them clean again. [Reply]  [No Email]
Tim S 01-27-2013 08:43:33 75.49.13.105 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 06:57:57   Since it seems to have gotten water while setting, it"s possible the water pump is the problem, I would check that angle first, if it"s possible to get the oil pan off do so and pump the radiator up a radiator tester, then look for the source.It could be a leaking liner too. [Reply]  [No Email]
Tx Jim 01-27-2013 08:51:33 67.142.163.21 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to Tim S, 01-27-2013 08:43:33   I agree on checking the water pump as it's driven off of camshaft/timing gears [Reply]  [No Email]
d9gdon 01-27-2013 09:36:22 76.1.99.192 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to Tx Jim, 01-27-2013 08:51:33   Thanks for all the replies! I'll check the water pump first. Glad to know it's gear driven. That could be where the coolant got in there. It hasn't been cold enough to freeze it this year and it had been tested to 20 below zero. It didn't run but about 3 minutes altogether after it started blowing steam out. Just long enough to put the hydraulic cylinders in the transport position. This post was edited by d9gdon at 09:39:04 01/27/13. [Reply]  [No Email]
buickanddeere 01-27-2013 14:26:55 209.240.113.152 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 09:36:22   The coolant can measure -20F and be no good. The corrosion inhibited is just as vital in a wet sleeve engine. , If the inhibitor is depleted, the sleeves will cavitate pin holes. [Reply]  [No Email]
skip33652 01-27-2013 08:27:55 68.69.88.208 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 06:57:57   check waterpump first then head gasket.Paul [Reply]  [No Email]
David G 01-27-2013 08:21:53 205.215.206.18 Report to Moderator	Re: JD 6068 engine blowing steam from blowby in reply to d9gdon, 01-27-2013 06:57:57   You have plenty of work and money spending ahead of you. Did it freeze up in cold weather? [Reply]  [No Email]