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K Hills

khills

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Howdy folks. New to the forum. Wow so much info here how can I not join? I've got a 1998 GMC Sierra 2500 HD with a good ol' 6.5 diesel in 'er. Got it from some backyard mechanic wanna be. Fixed a ton of stuff on it. Got more to do. lol.
 
Welcome.
It helps a ton to fill out your signature line with truck details, modifications, etc so each time you post we can look right there and realize what we are workin with.
 
Welcome to the forum.

Make sure to get a working lift pump on there very soon. Preferably before you crank it up again. Do you have a fuel pressure Guage? How do you know it’s not working? Having a non working lift pump means that the injection pump has to suck fuel all the way up by itself and that wears it out quick. Also make sure to add something in the fuel for lubricity. I add 1 oz. of TCW-3 2 stroke oil to 1 gallon of fuel.

Get the turbo working so you aren’t blowing coal every time you drive it. The cab bushings could be wore out causing the cab to sit lower than the bed.
 
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Does anyone know how to adjust the fuel rate on this thing. Does it have to be at operating temp? Do you have to install the plenum so it can read boost and iat? When I adjust it the rate jumps all over the place making me wonder if it has to be put back together. What a pain!!!
 
It's done by moving the OS. And yes it can be a pain. Which is why the precise scribe mark is so important. It does need to be at operating temp otherwise the computer is throwing timing and a faster idle at it which will affect the idle fuel rate
 
Yeah, unfortunately when you mentioned you put it back -kinda close- and ak diesel driver mentioned it, the rest of us were cringing or at home saying “OH NO, y u do dat?” Not that many of us didn’t learn it the same way as you...

One of the tricks is to plug in the block heater to get it warm as possible before starting.
 
lol. Ya I'm kinda crazy. Don't mind getting into things and learning as I screw up. lol Been turning wrenches for 30 years on highway trucks but learning about the smaller diesel. I love that its so easy to work on compared to all that computerized crap that just when you understand it "they" change everything and/or make it more complex.......way more than it needs to be. Thanks a lot for the advise guys. I sure do appreciate the help.
 
lol. Ya I'm kinda crazy. Don't mind getting into things and learning as I screw up. lol Been turning wrenches for 30 years on highway trucks but learning about the smaller diesel. I love that its so easy to work on compared to all that computerized crap that just when you understand it "they" change everything and/or make it more complex.......way more than it needs to be. Thanks a lot for the advise guys. I sure do appreciate the help.
HAAAHAAAAHAAAAA, funny You should mention that, about 12 years ago, I retired from the Montana DOT as a wrench turner. I was fortunate enough to have had the opportunity to work on a phew of the 6.5 trucks back then, and, even with working on them, I still wanted one, mainly for their simplicity and cost of replacement components.
 
Ya know what the 6.5 with ds4 reminds me of- the first d-dec series 60.
Not all same problems, definitely not same solutions! But like how much a non computer one was so easy and they learned on first d-dec. On similarities, overheating. Cold start, but 60 loved starting fluid. Throttle fly by wore issues. Wiped bearings when a service is missed of crappy filter. And while 60 ate wrist pins, the 6.5 eats balancer- and both lead to that beating the heck out of crankshaft.

Fuel/oil place I worked at had a ton of both engines- me and the other wrench spinners joked how it was a great father son relationship except the little guy was older. I said it was diesel ghost haunting Detroit on the 60 for the evils they let GM get away with on the 6.2/6.5.

One place they were polar opposite: mpg. Funny how one was the best in its class and the other, well, bless their heart at Detroit for trying hard on the 60...

khills: Something to take to heart right away with this engine- you cant treat it like a regular diesel. 50% of your pro skills will actually hurt you on this engine. GM penny pinched the actual design that Detroit gave them SO bad that the thing is really not good to own until you learn the correct things to extend it’s life. Seriously do 40 hours reading the stickies and twll yourself you are being paid $100 per hour to do it. Saving you replacing an engine for four grand is easy math.
Once you get it running ok, we can hit you with a list of things to do right away to keep it from self destructing- things that in big boy diesel world you wouldn’t do normally like new balancer and matching pulley at every 100,000 miles.
 
Thanks for your help boys. So here's the update. I got the fuel rate to 8 at first start up with a warm engine. Then it jumps to 12 for couple of seconds them stumbles, jumps to 15ish sets a p0251 code and starts knocking like a bad injector and has a miss. If I unplug the optical sensor it starts a little hard but runs great with no knock. No matter what I do the fuel rate always settles at about 15-16, 14ish when the optical sensor is unplugged. I'm suspecting the sensor is no good but having a hell of a time trying to find a new one here in fricken freezing canada.
 
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So plug back in the optic and unplug the crank sensor. Does it start at like this? If not- bad optic or the optic is way far out of adjustment
 
Hi guys. Its been a while. So I ended up replacing the I.P. When I installed it I rotated the pump so the dowel was in the same position as the old pump. When I went to install it, it didnt line up with the gear. So I figured the pump may have rotated while fighting to get it out. Anyways it's really hard to get it started and it runs with a miss until I rev it up a bit to around 1000-1500 rpm and it runs beautifully but always smokes and smells rich. I fully retarded the pump and it idled perfectly for a couple of minutes then ran rough again. I tried to adjust the static timing to 3.5 but it read 13-14 no matter how much I adjust it and the tdc off set is stuck at 2. something or other. I'm using an old snap-on MT 2500 scanner. I'm wondering if I'm out a tooth and if you think it would run if its out. Also when I checked it I lined up the notch in the balancer to the crank sensor figuring that would put it at tdc and it sure looked like the dowel on the pump was at 6 o'clock. Whatchya think?
 
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