D6c 69j

[wrwtexan]

I have been soaking and rocking (3-5 degrees) my D6C 69J posted under "New toy" for several days now and finally removed injectors and poured lube down all six holes. After 2 days, it still will not begin to turn. Are there any old tricks that sometimes work on stuck pistons without pulling the head? This machine is in public work shape overall and I would like to fix the engine to match so I am probably going to pull the head and see what needs to be done to fix it correctly, but would like to see it run first if possible. Looking at the oil pan, it extends back over the crossmember saddle several inches with little clearance for access or tools. Can the pan be removed in the tractor or does the engine have to come out? I can handle it but don't want to pull it if I don't have to.

 

[stray cat.Inc]

Yes the pan will come out, there's not much room. Remove the sump, then the oil pump. The scavenge pipe stays with the plate and it comes off last. Does the crank move at all, or is it solid?

 

[Plant Fitter]

What about getting an old injector, remove its internals, and weld a hydraulic fitting on the top of it.

Put a bronze rod down each injector hole, and find a piston which is mid stroke, and has closed valves. Remove the rocker arms if necessary to close the valves.

Fit your dummy injector to injector hole above the piston that is at mid stroke.

Then connect it to an Enerpac pump with a hydraulic hose.

Pump oil into the cylinder, which will force the piston down.

When it gets to the end of it stroke, repeat on another cylinder.

The Enerpac pump or any other similar hydraulic pump should give plenty of pressure.

I haven't tried this trick before, but always thought it would be worth a go if I had a situation like yours.

I have heard of it being done with a grease gun, but as you don't want to pull the head if you can help it, oil might be the best trick as grease might hang around in there and cause excess compression pressure if you get to starting it up.

Good luck, let us know how you get on.

 

[Nige]

If it will move 3-5 degrees and no further I would say there is something mechanical locking up somewhere inside the engine, if the pistons were stuck I don't think it would move at all.

 

[Old Magnet]

Not unusual to have a slight amount of movement as the pistons run into rust dams on the cylinder walls.

 

[95zIV]

How much force are you using? Would a bigger wrench on the flywheel help? It sounds like it's loose just needs a little more "oomph" to break over the first tough spots. With the amount of pure force those engines make when running, I don't think that you'll be able to apply enough to hurt anything by hand.

 

[kshansen]

When it turns the 3 to 5º, does it turn easy? Does it make any sound when it comes to the end of this movement? Is there signs of water in the intale or exhaust?

This should have aq 3306 engine which is very easy to work on. I'd consider pulling the head to have a look at the cylinders and pistons. If the problem is rust in a cyliner or two you could clean it out the best you can and if you get it to trun I'd reassemble with the old head gasket and such just to test run it and be able to move to better place to do the actual repairs.

Just be careful trying ot turn it over with head off or you will push the liners out if there is rust. Make some plates to bolt on with head bolt hole to keep them in place. Even som large flat washers and short 5/8 bolts would work.

 

[DPete]

Nice looking 6, if there is very much wrong with it you should be able to get a good take out engine easy enough.

 

[wrwtexan]

My impatience finally got the better of me and I pulled the head off this evening. Number 4 hole is the hold up and doesn't look very bad but it is stuck tight. I turned the crank and it pushed the sleeve out of the block. I never could get the piston to budge in it. As good of shape as it's in, I'm going to pull the pan and replace #4 sleeve and piston and clean up the rest as they still have factory hone marks in them. Can't have been run much or they would be well worn or gone.
Next expense is likely replacing the injection pump as it has been open and was the cause of the tractor getting into its current condition.

 

[kshansen]

My impatience finally got the better of me and I pulled the head off this evening. Number 4 hole is the hold up and doesn't look very bad but it is stuck tight. I turned the crank and it pushed the sleeve out of the block. I never could get the piston to budge in it. As good of shape as it's in, I'm going to pull the pan and replace #4 sleeve and piston and clean up the rest as they still have factory hone marks in them. Can't have been run much or they would be well worn or gone.
Next expense is likely replacing the injection pump as it has been open and was the cause of the tractor getting into its current condition.

Why would someone let a good machine just go to hell like that? What would have been a few hunderd dollar repair is now going to be in the thousands. As for the hone marks, you'd be surprised how long they will last if there is a good air filter and regular oil changes. Hope you can find a good used injection pump for a reasonable price.

 

[wrwtexan]

The owner had started working on the injection pump and then died. The machine sat for 8 years in its current condition. The sons were offered more than what I gave for it at the auction so their loss is my gain. I couldn't afford it if it were running but being able to perform my own repair work, I can buy and resurrect what others might consider junk.

 

[D6 Merv]

If your going to pull one liner, you may as well pull the lot.
Often its not the inside, but the outside condition of the liners. Pinholes in them from cavitation. If nothing else, pull them all to replace the liner seals. You,ve already got most of it apart

 

[kshansen]

If your going to pull one liner, you may as well pull the lot.
Often its not the inside, but the outside condition of the liners. Pinholes in them from cavitation. If nothing else, pull them all to replace the liner seals. You,ve already got most of it apart

I would agree. Especially when you say it has been sitting for 8 years. I know it's easy for Merv and me to spend your time and money but for the price of a few orings and a set of rings you will know what you have when you crank that machine up for the first time. Plus pulling all the pistons and liners will let you see up close if there is any damage to the crank or rod bearings from sitting all that time. You are going to disassemble the oil pump and check it out too right?

 

[wrwtexan]

I hadn't planned to do that much extra work, but y'all do have a good point and I have had one liner replacements bite me on IH tractors so I probably will pull all and check evertything over so when it is running, I'll know what I have. What about checking the oil pump? The injection pump failing is what shut the machine down. Something else which has crossed my mind, is will all the rust particles on the other pistons act like sanding grit and eat the sleeves if not cleaned out?

 

[D6 Merv]

Your best off to pull the lot. They may very well clean up inside and out. And just new seals and a set of rings. As long as theres no external pitting [cavitation] and .005 thou or less bore wear they,ll go again. At least that way you will know what you,ve got.
I,ll be interested to know what your repair options and cost will be for the smfs pump. Down here at the bottom of the world they 'could be' a troublesome item with lack of maintence. Some were replaced with the old compact scroll pump when and if the owners were lucky enough to locate a earlier wrecked engine. But your options in the US would be much better than what we have.
You,ve still got a good looking cheap reliable dozer at the end of it all :drinkup
complete governor and fuel pump group no is 6N5227

 

[wrwtexan]

My curiosity got the better of me again and I removed the side cover off of my injection pump. The inside was clean and everything moved as it should. They are built just like the hydraulic head (except one plunger per cylinder instead of one for 6) on an American Bosch Model 100 pump with the fuel rate controlled by a slide valve over the inlet of the pump plunger unit, which is a proven design. As everything appeared to work there, are the governor controls where these pumps give problems? Is the rear half lubed by oil or fuel (appears to be diesel)? I am not above cracking it open myself and seeing if I can fix it. I wish I knew what caused it to quit as to have an idea where to go.

 

[D6 Merv]

Everything is lubed by diesel. no oil anywhere. Is a gear type lift pump in the front of the pump. Lip type seals on the shaft can give trouble; leaking is visible out of the drain tube at the front of the pump.
good everything is clean inside, have seen some real bad ones full of water with the camshaft and lifters all pitted and requiring replacing, then it gets expensive. Whatever you do, do NOT disturb the postions of those sliding sleeves on the control quadrants. You need the special cat tooling to reset the sleeve positions.
If you get yourself a 3306 service manuel it tells you the disassembly and assembly procedure for a lot of the stuff you can do yourself.
Might have been a possibility this engine was originally just sucking air in the fuel as to why it wouldn't run ??

 

[wrwtexan]

Thanks for the pump info. I pulled the rear governor cover off and all seemed fine in there too. This pump should work if diesel is in it. I am wondering after draining the engine oil (8 gallons)which smelled like old diesel and very thin, if it was possibly leaking fuel into the crankcase or, do I understand if it leaks, it doesn't go into the engine? I won't change any settings. I'm going to put filters on it, fill it, and spin it over before I put a new sleeve and piston in the engine and see if it will pump. I am going to have good laugh if I bought this thing for 11k and put less than $500 into it to get it running.

 

[kshansen]

Any chance you have access to a set of injectors off maybe an old Mack engine?

You could hook them up to the fuel lines and see if the fuel pump can produce the pressure to pop them. Just don't get you hands near them while doing this fuel injected into skin is very bad thing.

We did something like this years ago to find a problem in an engine not running right after a rebuilt pump was installed. Did two cylinders at a time and ran engine with injectors in separate coffee cans to catch the fuel. Found one cylinder was way off on volume of fuel from the other five. Turned out to be a defective plunger in the fuel pump, new from factory.

 

[wrwtexan]

I have some injectors from an IH engine that will fit. Excellent way of checking for weak output.