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Can someone help me out with instructions on replacement of a '95 injection pump? Scans? Haynes?

Thanks,

Capt. Crunch
 

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Can someone help me out with instructions on replacement of a '95 injection pump? Scans? Haynes?

Thanks,

Capt. Crunch
Now get yourself some good ziplock bags, and use them to hold the bolts you remove. Keep them in groups, like for the intake and the alternator bracket. This helps tremendously when putting it all back together. Some of my bags only had 3 bolts in them.

Unplug wire harnesses as you need to, but label BOTH ends. GM makes it hard to plug up the sensors wrong, but why take a chance. A small tape flag with "A" "B" "C" and so on, on both sides of the plugs make it easy later.

Remove the upper and lower intakes seperatly. Getting the intakes off is not as daunting a task as you would think. Make a sketch of what holes hold bolts and what holes hold studs. Dont forget to unbolt the fuel filter, You dont have to remove it, but it has to come off the intake. A 15mm deep 6 point socket and a speed handle makes the job pretty easy. Dont unbolt the coolant crossover. It can stay in place. Stuff a shop towel into each intake port to keep anything from falling down into the engine.

Once the intakes are off, you will see the
pump, and you will dispair at getting the injector lines off. Follow the line back from the #1 cyl, and mark it at the pump. It should be on the drivers side of the pump, just above halfway down. I use a small zip tie on the nipple to mark it, just so you dont loose track of the #1 spot on the pump.

Remove the #1 and #3 line nuts at the injectors and remove the #1 line nut at the
pump with a 3/4" wrench. Carefully slide (DONT BEND) the #1 line back in its bracket just enough to allow the wrench to fit on to the #3 line nut. Remove the #3 line nut and remove that pair of lines from the truck. LABEL EACH LINE NEAR THE PUMP END!

Now you can remove the line nuts for the lines on the top of the
pump (8-7-2 and 6). If you undo the lines at the injectors, you will find you can move them a little for wrench clearance. I wound up leaving the 6-8 pair attached to the injectors, because getting to them was a pain in the @ss.

Before getting the bottom 2, I removed the cap over the fuel solenoid, and undid the wires. Getting the lines off is not fun, but its not impossible. You just got to work at it.

as each pair of lines comes loose, remove it from the truck. (you did label them, right?)

Now comes the fun part. It helps to have nerves of steel.

Remove the oil fill tube and grommet off the front of the timing cover. Inside you will see a large nut and hopefully some smaller nuts. You may have to rotate the engine. Use a 15mm on one of the damper bolts and turn in in the 'tighten' direction. Grab some help, and give them a mirror and a light and have them stop you when one of the smaller bolts is inline with the oil fill hole. Remove this bolt. and rotate the engine again. Repeat until all three bolts are out.

MAKE DAMN SURE YOU DONT DROP THESE BOLTS INTO THE ENGINE. In this one area, you want to work slowly and cautiously! As soon as the bolts were finger loose, I stuck my finger in the hole and used my fingertip to make sure the bolt stayed in the socket. Painful, but worth the effort.

After all three bolts are out of the gear, you may remove the 3 nuts holding the
pump on. First scribe a line on the pump bracket that lines up with a distinctive part of the pump. It does no good to draw a line on the pump and bracket if you are replacing the pump. there is a part of the pump flange that angles down, I used that as my reference.

Start at the one on the lower passenger side. It is the hardest to get to, and you might as well get it while you are fresh. I used a standard 15mm wrench with no modifications. You may want to bend or grind on the wrench for clearance. It may make it easier, but its not neccisary. Then get the drivers side nut, and finally the top one. With all three nuts off, now the
pump will slide out. Remove and discard the gasket.

I'm not sure if you can pull the timing gear out of mesh or not, but I dont think you want to find out. BE VERY CAREFUL AROUND THE TIMING GEAR!

When installing the new
pump, rotate the pump so the index pin in the gear hub is aprox. in the same place as the old pump. NOTE! GM, in their infinate stupidity, put the index pin in the same bolt circle as the bolts. This means its entirely possible to stick the index pin through a bolt hole and you wont know it until you try to install the gear bolts and nothing lines up. I had the pump and all lines on when I relized that I did JUST THAT! Talk about excessive profanity!

For that reason, I recommend putting on the top
pump nut to hold the pump in place, and then the gear bolts, before doing anything else. I used blue locktite on those bolts. I found using a small mirror to help get the bolts lined up with the holes helps alot.

Install the other two pump nuts. How, you ask? Simple (sort of...) I use a coat hanger to fashion a long wire with a small hook. I hung the nut off the hook and used a long screwdriver to start the nut on the threads. Its not easy, and can frustrate the hell out of you, but if you stay with it, the nut will eventually start. Have a magnetic pickup handy for when (not if) you drop and nut and have to fish it out from underneath the pump in the engine valley.

Once the
pump is line up and the 3 nuts secure, go about re-attaching the bottom injector lines on the pump (now aint you glad you labeled everthing?)

the firing order is 1-8-7-2-6-5-4-3. Repeat this mantra every time you
install a line, checking and rechecking over and over.

Once you got the bottom lines hooked up,
install the Fuel solenoid wires and cap, and reattach the remaining injector lines.

Once I had all the injectors lines on and wires hooked up, I removed the shop towels and tried starting the truck. A 6.5 is more than happy to start and run will the intake off. I DO NOT recommed this unless you have balls of solid rock. You could very easily suck something into an intake port and do something dreadful to the motor. I did this just so I could check for leaks and whatnot before putting on the intake.

It took some cranking but it finally started. It took about 30 seconds to purge all lines and settle down into the familiar 6.5 idle. Everthing looked good, so I shut it off and installed the intake, alternator brackets, oil fill tube, and anything else that I had removed.

A quick road test confirmed that everthing was okey-dokey. It is conventional wisdom that you should re-time the
pump anytime you mess with it.
I got this from another post. hope this helps
 

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The two things i would add to this great post is buy a set of line wrenches. They won't work on all the fittings but most of them.And cap all lines and fittings as removed to keep all dirt out. I used masking tape on the ones i removed today. One very small piece of dirt can raise hell with injectors.
 

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Discussion Starter #4 (Edited)
Thanks for all this information guys. Will, thats really above and beyond!

bk- Do you have any idea if the PMD would cause a code 34? DTC 34 - Injection Timing Stepper Motor Fault? keep in mind I have a crank but no start.

Based on the fuel in the t-valve and the fuel filter I'm thinking its the IP and or the PMD.
 

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I use old egg cartons and a sharpe to keep the bolts in order of removal. I would check the stepper motor first like dieselpro said in your other post. the PMD would be cheaper and easier than the pump and it wouldn't be a bad idea to replace it with the pump if the pump needs to be changed.
 

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If you have not done the Diagnostic Checklist, DO that first. Eliminate the cheap and easy stuff first before venturing out to change the IP.

Just my 2c.
 

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pmd won't cause a stepper motor fault. Ecm uses temp. and rpm to set timing advance with stepper motor. Ip timing being out of usable range will set a dtc 34. The motor will bottom out and not reach desired advance, setting code. Stepper motor failure is common. If stepper motor can't advance timing for cold start it won't start. Plug the engine heater in for a while and see what happens. That is one of the reasons for that question in the checklist.
 

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I use little 2-3" x 2-3" aluminum foil squares to seal sensitive connections.

Just center the connector on the square and wrap the rest around the connector - it forms around and stays on and keeps out the dirt. The heavier, the better.

Larger squares for larger objects.
 

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Discussion Starter #9 (Edited)
ok. I'm in the garage and i'm stuck at the timing gear bolts.

"Remove the oil fill tube and grommet off the front of the timing cover. Inside you will see a large nut and hopefully some smaller nuts. You may have to rotate the engine. Use a 15mm on one of the damper bolts and turn in in the 'tighten' direction. Grab some help, and give them a mirror and a light and have them stop you when one of the smaller bolts is inline with the oil fill hole. Remove this bolt. and rotate the engine again. Repeat until all three bolts are out. "

How do I turn the engine to gain access to the bolts? The pulley at the very bottom has four bolts and that didnt yield any results. The main bolt in the timing gear is about 50% visable and I have no idea who to turn that if that the way. I figure cranking the engine would work but do I really want to crank the engine with all this stuff removed?? Help
 

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In my timing working on these trucks one piece of advise is to only remove the injector lines on the injector side and leave the others on the pump. Remove the pump gear bolts first and be careful not to drop them. Then remove the 3 pump flange bolts. The pump will slide right out. Set the old pump beside the new one and swap the lines.
 

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I figure cranking the engine would work
DON'T.....
InFact - Disconnect the batteries!
*Something* falling and shorting, or somehow energizing the starter will ruin your day. Never try to cheat Murphy!!!

No big deal to remove the serp belt and fan shroud to get at the crank bolt.
 

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you will need an 1/2 inch drive breaker bar, 3 inch extension and the socket that fits the big bolt that holds on the crank shaft dampner. you should be able to turn the engine with that. DO NOT BUMP THE STARTER WITH THE KEY. You are sure to mess up something bumping the starter eith the key.
 

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Will92104 said to re-time the pump any time you mess with it. How do you do that? I have another problem that I think mine is out of time.

From what I've read the mechanical pump has a solinoid that advances the timing until the engine warms up. My 93 starts and runs fine til it warms up, then it misses, rocks and shakes the whole truck. I've already replaced lift pump, oil pressure switch, lift pump relay, and injectors. It doesn't have a PMD to overheat and mess it up.
 

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Discussion Starter #14
I got as far as the nuts holding the pump. I can't get the last nut off with a standard 15mm wrench. Do I need a half moon wrench or a special tool?
 
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A half moon makes it easier. But some times if you can find a diffrent brand of wrench they might be clocked diffrent. Or flip to the other side of the boxthat should change how it the wrench is clocked.
 
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O and once you getting it moving that might be a great place for a gear wrench.
 

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Will92104 said to re-time the pump any time you mess with it. How do you do that? I have another problem that I think mine is out of time.

From what I've read the mechanical pump has a solinoid that advances the timing until the engine warms up. My 93 starts and runs fine til it warms up, then it misses, rocks and shakes the whole truck. I've already replaced lift pump, oil pressure switch, lift pump relay, and injectors. It doesn't have a PMD to overheat and mess it up.
Is your truck OBD1 or OBD2, there are computers that you hook up to the OBD connector to set the timing of an injection pump. If your going to do it yourself, you need to see what the timing is on the computer and then twist the pump to get the correct timing. easiest way though is take it to a diesel repair shop. Other members have stated that it is not to expensive to have them do it and only takes about an hour or so to do. might be your best bet to get it done by a repair shop.

UPDATE: Sorry, i just read that your truck is a 93 and mechanical, this will not help you so maybe someone will chime in to help you.
 

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Discussion Starter #19
Well, the truck was put back together on Saturday night but I didnt have enough charge in the batteries so I put the charger on them so I could have something to do after the superbowl.

The truck cranks but doesnt start. I was told I need to purge the fuel lines before it will start but I was dissapointed I didn't get anything other that a decent crank. The unfortunate reality set in when I remember this is the same condition the truck was in before I replaced the pump/pmd.

At this point i've spend about $800 in parts and gaskets, $300 in tools, 42+ man hours (2 people). The time has come for professional help.

Does anyone know of a 6.5 mechanic who makes house calls or has a shop in North Orange County?
 

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The battery needs to be fully charged to crank from your sub condition.

It takes a long time to crank to purge the fuel line on top of the fuel filter.
The easiest way is to jump the LP for a little while to let all the air out before cranking.
 
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