Diesel help?

I have an '86 K20 with the diesel engine in and been having some troubles lately. I know absolutely squat about a diesel but anyway thougth somebody might have some clues for me here.
Basically the truck runs great till I shut it down. After shutting it down I can't get it started again till it cool down. I thought it was the starter and/or the batteries, so I toolk them all to the local parts shop and had them check, they checked out as being good. The engine turns over really hard and slow in the truck which made me think these were the culprits. So slow it makes a person think the engine is retarded in the timing but I am not sure if diesels can get out on time?? maybe somebody can clear that up for me as well? I have browsed all aroun dthe internet looking for help and found a site called Diesel Place, I posted there hoping somebody can help me out better from there but thought it would also help to post here.
Also, I will let you know that the ground wire from the main battery is getting extremely HOT for some reason. I thought it was just a bad connection and took ALL my battery connectors on both ends off an dcleaned them all up, it still did it. So I ran a second ground wire from the first battery(the one that is getting hot) to another location on the engine block. Now both are getting hot and it has not helped out any.
I have not had this truck for to long but am wishing now I never got it, been one big headache after another. I am ready to swap out the 6.2L diesel and put in an ole trusty reliable 350 but really would like to get this up and going first that way I could at least try to get rid of the engine to some other fool, lol. If not the engine maybe the entire truck so I can at least get an older truck I can play in. That was the intentions for this truck till I found out diesels are not good to play in the mud with, not enough engine RPM's there and to heavy.
Anywho, maybe somebody can give me some ideas of what is wrong with this engine. Much thanks to any who can give some input of what it may be.

The 6.2 is a four stroke Detroit engine. Diesels in general have real high compression as the compression is what ignites the fuel (and thus makes it a diesel engine). What gauge is the battery cable to the starter, and how long is it? I would run nothing smaller than a 2 gauge wire on both the starter and ground. These are large cables. Get 1 gauge if it's available. More amps to the starter equals a faster cranking engine.

If the engine's hot, you shouldn't have to worry about the glow plugs but if it's cold (and moderately cool outside), run the glow plugs for a minute or two before attempting to start the engine.

You can set the timing on the injection pump - however, I am not a diesel guy so I can't tell you how to do that. I am sure someone will come along and help out.

All the cables are 2 gauge except one, the one cable that is running from the hot side of the one battery to the hot side of the other battery is larger, I am thinking it is a 1 gauge. That should not be the problem, as I said I even have 2 grounds coming off the one battery cause I thought it was not making a good enough ground which was causing the ground cable to get hot.
The truck ran fine with no problems, not even starting when warm up until I put it in a huge mud hole a couple of weeks ago. I had it towed home by a buddy on a trailer cause it was not starting due to the exhaust packed full of mud. I pulled(cut) off the exhaust and ran a high pressure water hose up there to get all the mud out so the engine would start(wouldn't start prior to doing this). I started it long enough to make sure it would start and then shut it right down, didn't let it get warm or anything, maybe a total of 2 minutes run time. I then chaged all the fluids, oil and transmission filter and fluids. No water was in the engine oil at all but tranny is a different story. I still need to do one more transmission filter and fluid change(maybe more than one) but I started it up and drove it to my friends house probably a total of 6 miles. Shut it down and it did not want to start after I sat there for about 45 minutes. Took 3 hours for it to cool off enough to start. The next day I started it long enough for it to reach operating temperature and then shut it down and the same thing.
I am thining that maybe i should try throwing some water on the starter when it does this to see if the starter is getting to hot and not cranking right. The cool water may cool the starter down enough to crank properly, that would let me know if that is the problem anyway. I don't like doing that cause I have seen people crack the starter housing by throwing water on a hot starter but it is under warranty still and only 3 weeks old.

I am seriously thinking of yanking the diesel out and just dropping a 350 and a SM 465 Muncie 4 speed into it. Since I am not familiar with the diesels or automatic transmissions I am thinking this would be best for me. I would still like the diesel to run right cause I think I know where I sell it or even make a trade on a 355 enigine instead of the stock 350 I was looking at.

Well, the people at Diesel Place seem to think the 2 gauge cables aren't heavy enough. So, I called my local GM parts dealer and asked them what the stock cable size is supposed to be, they of course told me the stock battery cables for an '86 diesel is 2 gauge wire. I explained my situation with them and they seem to think the starter is not getting grounded to the block good enough(dirt or oil) or the starter itself is bad. I asked them also if they could test it and they said of course for a small service charge, lol. One way or another they want a dollar.
I am thinking the starter is definitely the problem and that maybe the parts store that tested it for me just didn't want to replace it and told me it was fine?!?!

I would take it to a local starter and alternator shop they will probably test it free. If you get it repaired ask for original equipment parts. If your wires are original equipment they should be large enough.
It isn't like you are trying to start in zero degree temperature. They sell a amp meter you just hold over the wire going to the starter it would be a good idea to check the amps.

There could be corrosion inside the battery cables turning the 2 gauge into a 10 gauge wire....
I wouldnt mind having that truck, I heard they still get around 20 mpg. Not bad for a 3/4 ton 4x4.....

They sell a amp meter you just hold over the wire going to the starter it would be a good idea to check the amps. When did you become a Moderator? ....Congrats........:sly: I think...

It showed up yesterday but I never recieved confirmation apparently the Dodge forum needs a moderator but I was asked by somebody from the Ford forum.
I think I will probably be on the Dodge forum but don't know for sure.

Alright,, information I found out last night kinda upset me a little. Sitting around drinking a little with some buddies the subject of the truck and what it is doing came up. I explained what a llot of people are saying might be wrong with the truck to my one buddy who I completely forgot about till last night that was almost bottle fed diesel fuel so knows quite a bit about them. he is not a certified mehanic or anything such as that but damn good at what he does. ANYWAY, he said I could go to his house and get a brand new starter and put on my truck and he puts a bet on it that as soon as the truck gets hot it will do the same thing and I could change all the cables to wielding leads and that won't make a difference either.
He said he would almost guarantee that the bearings in the engine are slipping/spinning and when they get hot it is cauing them to get into a bind, which of course is making way to difficult for the starter to roll the engine over and the reason why the ground cable is getting hot is due to that as well, to much draw from the batteries to the starter which is trying it's best to turn over an engine that is basically trying to lock up.
So, I guess it is one of 2 things, fix it or swap it out for another engine which if I do that I will most likely put a 350 in it.

Oh, I do get about 23 MPG with this diesel, I know if I drop a 350 in it with as low as the gear ratio is it will get a lot less. That is when I would want to rework the entire truck, putting a 4 speed SM 465 Muncie in it, the 350, and of course change out the front and rear axles to a light duty 3/4 ton so I could get 3:23 gear ratios... can't forget the 35" tires that were on it too(that changes the ratio as well). Old truck I had got about 22 MPG on average and about 25 on the highway using this set up but I know all engines are not exactly the same so i doubt I would acheive the same results.

I guess for about $100 I should try to fix it though. The buddy I was talking to last night said he would give me a 350 that has been rebuilt for the diesel, so that means he still thinks there is hope for the engine, lol.

The buddy I was talking to last night said he would give me a 350 that has been rebuilt for the diesel.
More of a buddy f**ker then an actual buddy....
Do you have metal in the oil? Drain plug have shavings on it?
Weird knocks or low oil pressure? If so then maybe he is a buddy, if not then someone is trying to screw you out of an engine. IMO
If a bearing was spun then you would have metal shavings in the oil for sure....

I am still thinking the cables are corroded internally, reducing the gauge size.
I cut the ends off several car battery cables my dad had years ago. I was trying to wire up a winch to a trailer right before an auction I was going to. Out of 7 cables I got 2 that were good. The others had green death inside the "protective" coating. Luckily the 2 were long enough to connect the winch to the battery........then I didn't get anything at that auction. :shakehead

My $$$ is on the green corrosion angle or a marginal starter. I think that the guy with the bearing theory is blowing smoke up your "tailpipe".

Bob

If just the ground wire is hot it indicates it has high resistance. I didn't notice this before. Years ago they used braided ground wires with no insulation. I have connected two short wires by using a piece of copper tubing crimping it and soldering the fitting. I didn't bother putting insulation on this ground wire.
I would take my pocket knife and cut 6 inchs of insulation off next to the negative terminal on the battery. If its bad buy a new ground cable and check if this corrects your problem.
From my experience I found when a bearing goes the motor would knock badly. But I would go to a local machine shop that does diesels and ask
much cheaper than a new motor.
At the price of the repairs you are talking about I would pull the pan and look.
But I would take the starter to a local repair shop who does this type of work first. You can pull the starter apart yourself and check bearings and ohm the winding.
One advisor I noticed has a lot of machine shop experience send him a private email.

If a bearing was spun then you would have metal shavings in the oil for sure....

I will say this about that saying, that is not always true, I have pulled the pan off plenty of gassers and seen spun bearings with NO evidence of shavings in the pan or oil of it is caught in time.

As for the cables I have completely took of all the insulation of ALL ground cables and NO corrosion exist....NONE. SO, as for the ground cable getting hot that takes care of the thought of them being corroded but they are still getting hot when I try cranking when the engine has already been warm. These cables do not get hot at all when I start when the engine is cold, they don't even get the slightest bit warm.

So, the more I work with this thing the more I am ready to just say hell with it and pull the pan and check the bearings and crankshaft. I also did try my buddies starter which is almost the same as new and works fine on his other truck he has, I still get the same results on my truck. I also tried my starter on his truck and let it run for about an hour while we went and checked an oil well. My starter started his 6.5L he now has just fine, even after running for that long. So my starter is apparently not the problem.

It comes down to only 2 things that it can possibly be.... The bearings or possible that the batteries are bad even though they are testing good. I was going to ask my buddy to run them on his truck for a while to see what he thought and if he had any problems out of them at all.

I have spilled anti freeze on the connections on the block. Anti freeze is a good insulator. This would be easy to test use an ohm meter and check resistance between the block and ground wire.
Otherwise I think you made the correct decision.

Have you had a starting and charging system check done? I would have one done cold then again after it gets hot. Also how old are the batteries? All it takes is one weak cell or more to cause problems.

For a few bucks, you could replace all the battery cables just to rule them out.

Before you drop the pan, take off the oil filter and cut it open around the flange and pull the cover off. Look for flaky bearing material or other pieces of metal in the element. By now I'd think you'd have some sign of a bearing noise from it.

Bob, just trying to help!

If you haven't yet , grab an ohm meter and test resistance on all battery cables, etc. cold; then do it again after engine is hot. This will definitely tell you if the cables are the problem. If this is ruled out as the problem, you could pull the injectors and check for coking, or leaking. Leaking might load up a cylinder or two causing hard cranking but not a very likely possibility. You could also take all injectors out after engine is hot and see if it still heats up cables turning engine over with little or no compression causing strain on starter. If you do this hook up injector lines to temporary fuel lines to catch the diesel. If you still have the problem then you probably do have internal engine problems. Is this a "J" code engine (black paint) or a "C" code (red engine). Red engine has higher compression than black. Also possible torque converter/tranny problem (locking up when hot) from the mud/water bath. Another possibility is a short somewhere in the starting system that because of the mud bath only shorts when starting hot. I would also check the hot battery cables to make sure that they are copper and not aluminum. GM in the late 70's and early 80's made some battery cables from aluminum, and someone may have used an old cable on your truck. Good luck

The battery cables are copper. I have drained all oil and checked it for any metal shaving as well....NONE. While running though I used a garden hose and held it toward the bottom of the pan and it sounds like a knock in the rear part of the engine.?. Not sure if this is normal?
Talked t another buddy of mine and he also said that the mud could have caused a poor ground, his suggestion, wash the complete engine compartment with a pessure washer. He also thinks the ground cable that is getting hot is not the issue, it proves to him that it is the only one making a good ground and when cranking it should have 24 volts going through it of the other ground wire is not making a good contact. This I have not checked cause I did not think it was the issue, I will probably look at it better today and possibly move it to a better location. Buddy said where it is located could be the problem, it is mounted on the intake which he said could be aluminum, not a good conductor.
My buddy actually wants to trade me a 94 Cadillac Deville Concours or a 95 Probe and also pay me $500. Thinking hard about trading for the probe, lol. So to me that proves it must be something simple if he is wanting it. Claims he can get $1,500 just out of the heavy duty 3/4 ton axles. Says he is wanting to part it out.
I will continue to search for the problem though. It does act like the batteries or the starter to me. Which could be in the cables as well. I have never seen a bearing tighten up like that and not make a sound on a gasser, would think that the diesel would not be much different. I will probably use a multi meter and check for resistance in the cables to make sure they are good and also check the voltage at that starter when trying to start it. Was told the engine being warm could cause it to start hard if starting on 12 volts but easy to turn over when cold. So I guess that is where I may start first.

EDIT:
Just to let you know it is a "J" engine code.

You have two batteries in this truck. but it is still a 12 volt system unless it is a military truck. What are the first 8 VIN digits? Do both ground straps go to the negative terminals? The pressure wash might do the trick as something ocurred during the mud bath to cause the problem. Also on my 90 chev 6.2 3/4 ton 4x4 I obtained two of the large braided ground straps and put one from each battery to the radiator support. Don't know if it does any good but makes me feel better!

Yeah, I did some reading around and talking to my buddy some more and he said and what I read said that it was only a 12 volt system. Main battery with an auxiliary booster battery. Buddy told me it would have to be wired up differently than what it is to be a 24 volt system and explained to me how that was done but why not to do that. I would fry all my 12 volt accessories.
I have been a little aggravated with the truck lately so thought I would not do nothing for a while. If I go out and fool with it while being aggravated I would just end up breaking something.
The more I think about the truck though it seems like it almost has to lie in the cables or batteries, maybe even the starter but the batteries and starter are testing good.

I found out what the problem was. Something comletely simple as it usually is. It was the ground cable from the auxillary battery not making a good ground to the block. It was connected to the intake and I decided to disconnect the main battery and see if I could get any dash lights and seat belt buzzer to work with the main battery disconnected, I didn't so that is when I started fooling with the cables. I completely removed the ground cable and then touch it to the A/C bracket, I got dash lights and the seat belt wwarning buzzer so decided to connect it to that. So far it has been starting with no problems when it has been warm.

Now the next 2 problems I need to tackle. I need to buy a rebuild kit for my steering gear box. Whihc I wanted to ask if any have done this and if so are any special tools required? I have a major leak coming from the seal the shaft goes in, I know I can buy just a seal kit but decided I will buy a complete rebuild kit. Most of the time I have seen the bearings go out and cause a little bit of slap arpound to cause the seals to wear out. The kit is supposed to come with new bearings and seals, that should tighten the shaft back up and keep the new seals from getting wore out so quickly.

Then the brake caliper on the driver side is sticking. Figured the first thing I would so with it is remove it and then press on the brake pedal to push the piston out, after I got it out then take a peice of steel wool or emery cloth and clean the piston up. I will also check the o-ring in the caliper and the inside of the caliper to make sure no rust or debris is in there. Maybe buy a rebuild kit for the caliper if needed.

Anyway, I want to thank all for the ideas that helped me to get the truck starting properly.

See? I knew it was something relatively minor. Glad you solved the mystery once and for all.

I can't help much with the steering box, I'm sure you can find a good "how to" in a shop manual.

You might just want to get a rebuilt caliper to save yourself some work. I always take them off and blow them out with compressed air to get the pistons out. Really stubborn ones I've tossed back on the car and used the method you suggest. The GM pistons don't rust like other makes, they do get a ring of crud around them though.

While you're at it, I'd do both calipers and front flex hoses. GM products are known for collapsed brake hoses that can lead you to think you have a bad caliper.

Bob

Well, I did some other work on the truck the last 2 days(new steering gear box and brake caliper) and got all in good shape. I went out to test drive the truck to make sure I got the steering all lined up and brakes working fine and the truck started running rough. I headed back to the house and just as I got in front of the driveway it died. Just like I turned the key off, no sputtering or nothing, just died instantly. I tried starting it again and nothing. It rolled over really good and I had checked that it was getting fuel up to and past the fuel filter. It is getting fuel past the filter but it acts like it is not getting any fuel at all. I plan on disconnecting my glow plugs later and getting a can of ether or WD40 and just checking to see if it will "hit".
Ao, any ideas of what it may be? I was thinking wires, fuses?, injection pump(hope not), or maybe something like the shutoff solenoid. I had even thought the gauge for some reason took a dump on me, I got a few gallons of diesel and put in the tank to see if that was it. Of course it wasn't, that was when I decided to check to see if the electric fuel pump I have hooked up was working and fuel was going up to and past the fuel filter.

Anyway, any ideas to help me out would be nice.

I came across a cheap 6.5L engine I am thinking of swapping into the truck. It is turbo charged as well. I have been doing some research on this and found out I would definitely need the PCM from the other truck the 6.5L came out of due to the injector pump OR I could just use my 6.2L injector pump cause it is not electronically controlled.
I could also go with the option of just using the turbo and the exhaust manifolds off the 6.5L and put them on my 6.2L. I am not completely sure if what I want to do to the truck yet. I am slowly wanting power it up a little, nothing much and I figured keeping my engine and adding turbo would be the better choice, any thoughts? I also want to get rid of the TH400 automatic and get the 4 speed SM465 transmission or possibly even say heck with it and find a NV3500(light duty)or NV4500(heavy duty) 5 speed transmissions. My biggest problem would be finding the right transfer case to use. Maybe somebody would know that as well. Would it be possible for my NP208 to work on ither of these transmissions?

Been a while since I had been on here with my problems with this truck so I thought I would update. I had went out and bought 2 brand new batteries and all new "0" gauge battery cables to cure my problems of hard starting due to weak batteries and/or to small of cables. That seemed to help for a while but then the problem came back. I ran all new fuel lines cause I found out my buddy that had placed the electric fuel pump on the truck befor ei owned it used rubber lines and they were extremely close to the exhaust, actually they were laying on the exhaust and caused the problem of it shuttiong down on me and not wanting to start till the next day after it cooled down completely.
I also had some difficulty starting it when it was warm due to the fact I think the injection pump was leaking off a little in to the cylinders. I did not get a different injection pump instead I wired up a push button to operate my glow plugs manually, doing this from some other peoples advice helped to start the truck a lot quicker. I was told that when the injection pump leaked off in to the cylinders it is hydro locking it, adding a manual push button for my glow plugs would cause the diesel to vaporize making it easier to start. It worked of course!!

Anyway, I did a lot of work to the old truck and got it running and starting really good, I even solved my problem with the truck hard shifting at a high RPM with a new governor and then made a lot of tweaking adjustments on the modulator valve. I still did not trust for my wife to drive it just yet so I took it off the road completely and was using it on a friends farm till I was absolutely sure I wouldtrust the truck for her to drive if she wanted to.
While it was sitting at my buddies farm one of his buddies asked me if I would trade, I did. I got an 97 Escort and a 92 Isuzu 4WD pickup out of it. Both in good shape except the Isuzu needed a clutch. I know I kinda got a crappy end of the deal there but I was thankful a couple days later when I bumped into the young boy at the store and he told me the engine blew up in the truck. I asked him what he did and he said "nothing". I thought to myself maybe the noise I heard was a rod knocking then or the boy being yong he was a biut rough on the diesel engine thinking he could play around with it like a gasoline engine. So, for now I am over in the Escort & Grand Cherokee part of the forums. I sold the Isuzu pickup after I put a clutch in it for almost the cost of whatI had in the diesel pickup truck, so I almost made my money back but I now have an Escort as well.
I thought I would give this update to all who helped me out.

Thank you for the update!