HDG 6 Engine issues

Hey guys my father sold me his machine last year and I've used it a lot since. Dug my basement for the new house, cleared a bunch of brush and fairly large ash trees. Until yesterday it was running great. I hadn't drove it for awhile so it was a bit difficult to start but it finally did so I went to work. I was moving some dirt around so I could get to a nasty cedar I wanted to take out and the machine started to smoking(black and white) really bad and idling really high. I'm not a mechanic but I've put enough hours on it to realize something was wrong so I immediately headed for the shop. I parked it and when I went to shut it down I heard a big crack/pop noise come from the left. I had a ton of white smoke and oil coming from places it shouldn't. Does anybody have ideas what might have happened? Looks to me the gasket is a goner but I wonder if there's more to it???

Yeah I was thinking that might be the case but the loud crack/pop had me stumped. Do you think that was just the head gasket too? Or maybe just exhaust back fire? Seemed strange that it would come from the left side...

You know what come to think of it when I got down to take a look the dip stick was stick out about 5 inches. I didn't see a hole in the block and the oil was a little low but not too bad. I think I'll start with the head gasket and see what other things I find wrong as I dig into it. Anybody ever buy one of the rebuild kits off of ebay? I wonder how good those are???

Look behind the injector pump. They have a tendency to knock a hole in the block behind the injector pump, It will be hard to see if it is there. Good luck.

I do see a rubber gasket sticking out the left side of the block right behind the fuel filter. However, like I said before I'm no mechanic but there appears to be a plate of some sort with a couple bolts on it. Any ideas what that is?

A head gasket would be a good learning experience, for you... Did my first one, around 17, IIRR...  Really not much to it, just disassemble, and take pics, post them here, lots of videos on youtube, too.  Alls I had was a shop manual, and great older neighbor, who soon learned me the ways of the jedi shade tree mechanic.  There is no try, only do...

Edited by DiyDave - 12 Aug 2015 at 6:23pm

It does sound like a head gasket. First thing to do is re torque the cylinder head and note any loose or broken bolts. Then watch the oil level closely for water in the pan. Check radiator coolant level. See if any of this helps before ripping it down. HD6 gaskets require re torquing.

Start the motor again to see if this helps. With the motor running loosen the fuel lines at the injectors one at a time and check for equal RPM drop. This is SOP before tear down.

I was about to reinstall the cylinder head on my HD6 when I found a cracked sleeve. The top 3/8" of the sleeve had separated allowing the top of the sleeve to rotate independently.
Good luck

I have some left over parts if you need them-new valve cover gasket still in its package, new upper and lower rad hose, complete used dry air cleaner, a few rock used guards, a used 24 volt generator. If you need a head off this motor you can have the whole motor for scrap price bottom end is no good and has a hole in the block. The fuel filter, water pump, and starter are gone. I would like to get rid of it. I am in south central Iowa just south of I35

First off, is your machine early or late? A late unit will have a Allis Buda engine 4 cylinder, early units had Detroit Diesel 3 cylinder engines.

Those are the valve lifter covers (2) To pop that gasket and move the dipstick you had crank case pressure. Refer to the 13 August post.

Identify the motor. If the injectors are under the rocker arm cover you have the 6000 motor. If the injectors are on the side of the cylinder head you have an HD344. There is also a plate below the fuel filter in your first picture that will identify the motor. There is also one on the dash. The HD344 has a flat top piston. The 6000 motors have deep dish and shallow dished pistons.

Talk with HD6Tom about purchasing a rod and piston assembly if you have the same motor type.

If the machine is still mobile drive it up on 2 or 3 2x12's to gain working space underneath. cut a piece of plywood to fit between the track if you don't have a smooth working surface underneath the machine. Block the bucket about 2 feet off the ground so you can get under the machine. This is SOP. Before disabling the machine position it preparing for the worst case repair.

Worst case you broke the pushrod on an exhaust valve and broke a piston.
You should repair your HD6G Send me a PM and/or we can talk on the phone.

I attached 3 pics to my post, are you not able to open the links?