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OPS extension install questions

4thesporty

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Location
DFW....Texas
A little background first.

A while ago I bought the lift pump harness from KD. Apparantly this kit was not designed for an OBD1 truck because some of things don't match up with my engine compartment. (Verified by KD customer service...which is great BTW)

1) The side of the relay that goes to battery and switched power had to be completely modified for a clean install to the battery post and inside to the fuse block "add a tap"

2) The "T" connection I am supposed to screw into the OPS port does not screw in due to interference in the area.

So, I have an OPS extension coming from Leroy in hopes to somehow mount it to the firewall with the "T" screwed in and then both OPSs up there. However, I"m not sure my original OPS connector will reach so I'll have to fish that out of the wire loom too.

I am sure I have seen someones engine compartment picture on here that did something like this too.

Or, for those that have this extension installed, how did you mount it?

I really should have just made my own OPS relay mod after all this, but I'm now this deep into it and I want it done.
 
^^Was it the one that KD supplied?

I thought about just getting a nipple to extend it down there, but also thought this might cause more interference with all the wire looms in that area.
 
yours must be at the back of the head? mine was already in the valley and it seems to me I had to buy more fittings
 
Oh, ok, yes mine is in the back of the DS head.

It really is not that hard to change an OPS for me with the right socket and a 12" extension it can be done in about 10 minutes start to finish, if that. I will (hopefully) like the key on "prime" as well as the manual overide that this harness provides.
 
I have the JK kit on a 95 (OBD1). Mounted both sending units on a Tee mounted on the firewall, with a -3AN hose to connect them to the block. I did have to extend the wires for the stock OPS. It works great.

Sub070411-001.jpg
 
How did you secure that Tee to the firewall?

I used a straight bulkhead AN fitting on a "L" bracket I made from some flat bar. It takes several adapters to make it all work, there is a pipe to AN adapter on the branch of the tee to connect to the bulkhead fitting.
I could take a close up if you want, but I can tell you there is no easy way to make it.
 
No need for a picture, I understand how you made it.

Once I get all the parts in, i'll make something up that wil work. Thanks for the information.
 
There is a difference between older trucks though, with the fuse center being under the dash of 94 and older. And the lone LP fuse and relay on the passenger side firewall. 95 and up have the underhood fuse center. This kit is essentially for OBD1 trucks though, since OBD2 trucks have priming function and runs the LP off the relay at all times if the OPS fails. And OBD2 guys have a underhood wire for powering the lift pump.
 
Hmmm, interesting. I wonder why KD sells this kit this way then. He even told me via email it was designed for an OBDII truck.

To make it a little easier install would be to shorten the wire witht he ring terminal going to the battery, and legnthen the wire going to the fuse block. Then maybe come up with some way to only have to use one OPS, rather than two with a tee.

OR, maybe it's just me over obsessing about all soldered/shrinkwrapped connections, and everything tucking in nice and tight like it came from the factory with this equipment.:)
 
I drew a diagram of how to accomplish the same thing with a couple relays and some wire and a switch for guys that like doing things themselves, with about $30 in parts. Just using the same stock OPS, although I recommend the OPS extension to anyone too.
 
I have KD OPS/LP harness on my 95. Never have any problem putting the tee on the OPS port.
Of course that has been a few years.

It may be easier for you to take out the GP controller (make sure to disconnect the batteries).
That is the part above the OPS. Install the tee then put the GP controller back.

The 94 is a little bit different than 95 because I don't think there is a fuse box under the hood.
I am not sure where to tap the fuse.
 
Just to finish this thread, I did end up getting the ops extension but did not use it. I did as explained and removed the gp controller and was able to shift around some fuel lines down there to get the tee screwed in. I somehow fried the original ops in the process and had to get a replacement, but it is all installed now, just not working yet.

Continued in my nee thread, "kd lift pump harness install questions"
 
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