installing new pump

[turbostorm]

:confused: If installing new pump do you need to make sure that you have the motor on a certain cylinder, or do i need to just make the scribe mark and install the new one close.

[Oldsmoke]

I haven't performed this operation on my unit yet but normally there will be a timing mark on the drive coupler of the pump which you line up with a timing mark on the drive. If you have made a mark where the old pump was then line this up as well. Your truck should run but proper injection timing needs to be set with the proper scanner.

[Oldsmoke]

My GM service manual does not have information on injection pump service other than removal and replacement. From the picture it looks like the pump gear drives off an equally sized camshaft gear. It also appears as if this pump gear is bolted to a flange on the end of the pump input shaft. I can't tell but I would assume there is only one way the pump input shaft fits onto this gear and the pump gear being the same number of cogs as the camshaft gear all you need to do is line up the timing marks.

The two step pump removal instructions are:

1. Rotate the engine untill the timing marks on the pump gear and camshaft gear are aligned.

2. Scribe a mark aligning the injection pump flange and front cover.

Just line things back up again when you put the new pump on and your pump timing will be close enough to run. You then need to plug in your diagnostic scanner and set the timing exactly.

[big97daddy]

BIGDADDY HERE:p I am thinking of installing a manual injection pump on my 95 3500 hd,I realize the timing marks on the gear drive,and pump removal,and the pump instalation procedure,the question is how am I going to get proper timing at the pump,BIGDADDY:cool:

[Oldsmoke]

You want to swap in a mechanical type injection pump? I guess you would then need to disconect your ECM from the system and use a mechanical wastegate as well. You might also need to swap in wiring harness and dash and guages from an older model truck as well. I am thinking that would all be more trouble than it is worth.

The pump timing would be the least of your worries. For mechanical pump timing there will be an inspection hole or timing indicator somewhere on the pump that you will set to correspond with the timing mark on the crankshaft pulley assuming there is a timing mark.

[Chevylover]

You want to swap in a mechanical type injection pump? I guess you would then need to disconect your ECM from the system and use a mechanical wastegate as well. You might also need to swap in wiring harness and dash and guages from an older model truck as well. I am thinking that would all be more trouble than it is worth.

The pump timing would be the least of your worries. For mechanical pump timing there will be an inspection hole or timing indicator somewhere on the pump that you will set to correspond with the timing mark on the crankshaft pulley assuming there is a timing mark.

Don't forget the gaspedel also ! The 1995 is electronic, the manual pump is manually controlled gas pedel !

My opinion ?

Why to change backwards ? The pumps itself are no big difference. The only problem is the PMD. Relocate it with extension cable and cooler and in 99,9% the IP problem is solved.


Cu,
Sven

[big97daddy]

BIGDADDY HERE, Truck is 95 HD w/5speed,work truck,truck has electrical problems,right gas pedal and mechinacal boost are no problem,and theres a window on the side of pump for timming it,just was trying to think of way to eleminate further problems with truck,mech pumps were around for years with no problems no codes no shutting off no driver,fire her up and go,fuel milage is not a concern,truck is going to pull 24k trailer. I almost forgot youcan turn her up real easy,w/mech boost you can also put boost where everyou want within reason,just my thoughts,have to buy a new pump either way I go,would like your thoughts also.
By the way I want to thank all you guys who have helped me with your information, :) BIGDADDY