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Help, my name is Jimmie and I'm new to this...

Littleoleboo

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Hello everyone, I was introduced to this 1993 GMC K3500 many moons ago. Never knew it had a diesel engine either. Seen the guy drive it a time or two then I hadn't seen the truck in 8 years or so until a few weeks ago. Guy tells me the old guy had passed away and was a veteran. And didn't have anyone , a family. He tells me the previous owner had all these parts and wire, has painted this and that. I'm guessing that this guy was just trying to get a few more bucks with the extra parts. I'm into this truck...3 weeks and been here, there and read some good information about a 6.5 turbo diesel. Did I mention it's on jackstands , starters down, fuel lines off, plugged, return lines unplugged. Some hoses are cut. But most of what I see is a project that was underway to rehabilitate an aging vehicle. At first I'm thinking about just running away and saying pass. But the guy says I think the old man would want you to get it going. I start a new job in 21 days. I figured a few days she'd be up n running. No problem. Have a work truck . Why I got involved with something I knew nothing about is not like me. But I figured it can't be to much different. I now know after 3 weeks much more about a 6.5 with a mechanical injection pump, glow plugs and control module. Injection lines, return lines, FFM and PMD"s that I asked for the location of and was told to go do more reading. Now I know where it will never be. Oil pressure sending unit is a dual duty purposes fuel shut off and maintain the lift pump. That the t valve is water in fuel drain line that I don't have. And air is expelled through the cap that unscrews on top of FFM. The small screen inside the FFM. Thefilter. The heater at the bottom of FFM. Intercoolers, tranny cooler, gear box cooler, power steering cooler. CDR Valve. I p has to be timed, ckp sensors. Turbo. All in pieces. I put it together to see if it starts. I finally have fuel to the injectors and see fuel leaking from FFM. There an O-ring and another one I learned today in bottom inside heater and on side. I'm this close after cranking it I smell exhaust. That close now another hose. He doubled every cooler. Started rewiring corrosion. Harmonic balancer replaced and never seen so many filters. Found out he was a 6. 5 mechanic in Army. New airbag and compressor in bed along with suspension for front. The tranny rebuilt and new brakes and drums wait if she starts. A new water pump was installed along with the dual thermostat set up. Wiring for glow plugs, and a bypass of some sort I haven't figured out yet. Everything I see was everything I have read over about this engine that needed refining . KN filter. I'm stopped at getting it started. I have 2 700 CCA batteries and a new jump pack . Any help is greatly appreciated. I'm kinda wanna see her fire up or I'm calling in the...mechanic at 125.00 ph or the tow truck. Thanks for allowing me to get this out.
 
Don't take this personally... A truck in pieces and somebody completely unfamiliar with it, what could go wrong?


Getting it running for for daily driving reliability in 3 weeks seems a bit optimistic, but that is me.

Will need to focus on making sure everything goes back together correctly.

As an example of correct re-assembly, first thing that catches my attention is the dangling starter. Only good news is to verify that it still has a bracket, and if not to get one as now is the best time to install the bracket. This little inexpensive bracket will keep from destroying the block. Over time, people toss that bracket during a starter change and then later wonder why the starter bolt just cracked and destroyed the block.
 
Welcome to TTS! there's lots of folk here who can help. first thing is first as @JayTheCPA said. make sure you install that rear starter bracket on the starter! that little $10 piece is a block saver!! fill out your signature on all the details of your truck so we all know what your working on. do post some photos. it's always good to see these trucks when your showing some love on them!.

now that you have her cranking, try cracking the injector lines (easy to get to ones like the drivers side) and see if you are getting fuel out of the IP. once you see fuel tighten them back up. and one thing to remember, NEVER use starting fluid on them. not sure what type of climate your in where your located, but you might also need to make sure all your glows are getting power too. relay might be working or light in dash might come on but if there's no power to the glow plugs for about 5-8 seconds upon first key on cycle it might be a bear to start.

I'm sure others with more in-depth info will chime in to help soon. key is be patient and take your time. these old 6.5's last a long time :)
 
If you haven't tossed it yet, put the single stat crossover back on. It's a block off style and while there is some debate it has been shown to cool better than the duals due to the block off feature.

Also the single stat crossover makes it way easier to access the injection pump and move the pump to time it. With the mechanical DB2 pump on there you will have clearance issues with the throttle cable bracket and fast idle solenoid hitting the neck of the dual tstat crossover.

Also get rid of the K&N air filter and pick up a K47 air box from 1997 or later truck. You want to pull in cool outside air, not hot air from under the hood.

There's lots of info here on how to prime the engine and get it to turn over. Keep us posted and good luck!
 
KN filter

Get rid of this POS filter and use a real paper filter. More diesel engine rings have been dusted by this garbage than any other reason known.

A lot of things are different on a diesel.

You need RPM to get it to start. Weak batteries or 1 of 4 brushes bad in the starter and it likely will not start.

Pull some easy to reach glow plugs and see if you are getting a fuel mist when cranking:


The above shows priming the fuel system. By ear does yours crank over this fast? The rest of the thread may be of interest to you in re-ringing a 6.5TD.
 
Welcome to thetruckstop.
The people that sponsor this site, by paying for the privelage to advertise in this forum, they all know the 6.5 diesel through personal experience. The items that they develope and market are tested and tried uprated components.
About the only item that might be for sale that I would not purchase, at least until further testing can be done with it, is the higher volume, higher pressure water/coolant pump.
The advice given in this site is as good as gold in the vault so read what is typed and follow what is being said.
Your truck and enjun will run a very long time and be reliable too.
 
Welcome. I am going to agree with most of the above.
I been running k&n air filters for 40 years. Ran many engines to longer life than most people get out if engines and never did one suffer from it. Lived in Las Vegas area all that time and we are a dust bowl of really fine dust and trace amounts of natural occurring asbestos around here. We just learned in the dirtbike world in the 70’s to oil a little heavier than they suggest, which requires cleaning a little more often. I have roughly 40,000 miles on my optimizer and have it torn down from a broken glowplug destroying a piston. But my cylinder walls and rings were in absolutely perfect condition.
Yes there are better air filters available now days which filter better while they breathe better- but only 2 I have found and only one fits in the gmt400 air box.

So I say keep it for now, when you know you will keep the truck long term consider upgrading. Just oil it about 20% heavier than the factory recommended amount.

As to the single vs dual thermostat housing- Yes keep the single, but for now run what is on there if it is assembled and the hose fits- DEPENDING how far everything is assembled.
You can easily swap that around later.

For now, get it running. You don’t really know if it is a junk engine until it runs.

Post pics here, or YouTube videos and copy the link here. We can walk you through whatever ya got. Post and check often, some of us check up here a couple times a day.

please, type a couple sentences and skip a line, it is hard to follow the one big paragraph method.

You are best to keep everything in one thread for now.
 
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