Results 1 to 20 of 39

Thread: Duramax Diesel Conversions

Hybrid View

Previous Post Previous Post   Next Post Next Post
  1. #1

    Default

    Thanks, but I already subscribed as a member to alldata myself. Now I got the heater working (need to find the A/C engage wire, but I have some small problems left still. First, how should the coolant circle go through the heater? I have 3 pipe endings coming out from firewall, one I know is A/C pipeline, the other two are for the heater inside.
    http://stuff.e30club.org/images/suburban/hoses.JPG
    Problably the bigger one is intake hose and smaller outlet? Duramax has two exactly same size hoses, one is coming from the waterpump or near there and the other one is coming from that big hose, that goes to the radiator right side. Correct me, if Im wrong, but then the hot water comes from the lower hose, that goes to the radiator, goes through heater radiator and then goes back to the water pump? Of course, then it gets warm in car, when thermostat valve opens. And also I have A/C hose problems, if someone could explain me the schema, how I can fit them so my A/C fluid circle will be right. If someone can explain me, how I should fit those hoses, I´d be very grateful.

    Edited:
    Still one more little problem: I have that kind of wiper plug, that does not fit to the suburbans wiper motor, and it has 6 wires, but suburban has only 5, so any ideas? The Duramax wiper motor is different and cannot be mounted on the suburban body.
    Picture of my plug:
    http://stuff.e30club.org/images/suburban/wiperplug.JPG

  2. #2
    Join Date
    Feb 2000
    Location
    Montana
    Posts
    11,416

    Default

    Quote Originally Posted by Margo_325 View Post
    Thanks, but I already subscribed as a member to alldata myself. Now I got the heater working (need to find the A/C engage wire, but I have some small problems left still. First, how should the coolant circle go through the heater? I have 3 pipe endings coming out from firewall, one I know is A/C pipeline, the other two are for the heater inside.
    http://stuff.e30club.org/images/suburban/hoses.JPG
    Problably the bigger one is intake hose and smaller outlet? Duramax has two exactly same size hoses, one is coming from the waterpump or near there and the other one is coming from that big hose, that goes to the radiator right side. Correct me, if Im wrong, but then the hot water comes from the lower hose, that goes to the radiator, goes through heater radiator and then goes back to the water pump? Of course, then it gets warm in car, when thermostat valve opens. And also I have A/C hose problems, if someone could explain me the schema, how I can fit them so my A/C fluid circle will be right. If someone can explain me, how I should fit those hoses, I´d be very grateful.

    Edited:
    Still one more little problem: I have that kind of wiper plug, that does not fit to the suburbans wiper motor, and it has 6 wires, but suburban has only 5, so any ideas? The Duramax wiper motor is different and cannot be mounted on the suburban body.
    Picture of my plug:
    http://stuff.e30club.org/images/suburban/wiperplug.JPG
    In my 1989 Duramax conversion, the heater pipe closest to the engine on the truck's firewall connects to the upper heater supply hose coming from the Duramax engine. I bought a new silicone hose made for a 6.5 engined truck to sweep up and connect to the Duramax heater hose supply line.

    Wipers... I used a new complete in-cab wiring harness, and I maintained the original steering column. Using the 2001 harness wires used for the wipers, I made the connections between the wiper control stalk and the wiper motor (using the original electrical connector) using the 1993 wiring diagram. If your vehicle is newer and you're using the original steering column, use the matching wiring diagram to know what function each wiring connection is supposed to operate.

    Are you using the original steering column or a column matching your engine package (which is what I recommend for an easier install)?

    Jim

  3. #3

    Default

    To Jim: I´m using a Duramax steering column as well. Theres minor problems fitting it, because the lower bracket does not fit and needs to be welded to another place. Same with the shifting cable bracket on the steering column, because Im using my original Suburban shifting cable (it is tight)

    To THEFERMANATOR: Could you explain it to me (a simple schema or something), because I have zero knowledges about relays. I know, that I have one wire, what turns on the light in the A/C button, if I give there "+" from battery.

  4. #4
    Join Date
    Feb 2009
    Location
    ZEPHYRHILLS, FL
    Posts
    193

    Default

    The A/C control head in the 95-99 SUB's output's a 12V+ signal to the A/C system to request the compressor to come on. The 01 DMAX uses a ground signal from the controller to the ECM to trigger the A/C. So you would need to use a relay that is turned on by the 95 control head that would ground the A/C request signal to the ECM. And the A/C light in the control head is turned on by a controller inside of the A/C control head itself. Also the power for the blower motor in the HVAC comes through the origanal underhood harness that ran behind the engine and came down underneath the old coolant bottle. This is the same harness that origanally had all of the ECM wiring in it.

  5. #5

    Default

    Ok, I think I try to do so. Another sad surprise came up. I connected all wires, that is needed to run the engine, so I can start wiring power windows, electric seats etc. I turned the ignition on and only this yellow "Check engine" and glow plug lights came to life. As I don't have any oil in the engine, I didn't try to start it yet, just tried, if starter works and it did. Of course, I don't have a key, the lock cylinder is taken out and I have a big screwdriver as a key, but still, I suppose, Passlock will not disable any lights like battery or oil in dashboard? No gauges were working either. Its weird, because I haven't done any wiring myself, besides these red wires on the picture (they fit anywhere, so I did just put them somewhere)

    And also thereare 2 plugs left over under hood:
    (comes out from that red box)

    and two ones under dash: (yellow one seems to be like airbag plug, but that already connected on the steering column)

    Any ideas, where I should start tomorrow?
    Last edited by More Power; 02-10-2022 at 13:47. Reason: dead pic links

  6. #6
    Join Date
    Feb 2000
    Location
    Montana
    Posts
    11,416

    Default

    No gauges were working either.
    Several of the gauges are operated by the vehicle ECM via digital data - not directly by engine sensors. So, the ECM has to be installed for all of the gauges to work as they should.

    I would expect some modification of the steering column mounts would need to be done to get the newer style column installed. That is all pretty basic, and having the new correct column would make the overall installation a lot simpler. Personally, I'd get the correct Allison shift cable, and not try to reuse the original Suburban shift cable.

    If someone else started the electrical/electronic installation, and didn't document everything, you're in for some late nights tracing wires and figuring out what was done. In my conversion, I documented everything, and kept detailed records, both to help me in the future if I need to troubleshoot a problem and to help any future owner should I sell this truck.

    One aspect of the conversion I kept firmly in mind during the process was to keep the conversion as "factory" as possible. Any deviations from this are thoroughly documented (like the HVAC, wipers, etc). This would allow a GM dealer technician to troubleshoot this D/A conversion just like he would a stock 2001/2002 D/A truck. Nearly all circuits, fuse blocks, individual fuses, harnesses and all electrical layout are almost exactly as they are in the 2001/2002 trucks. The conversion guide was written from that perspective. One reason for doing this was because no one else had completed a GM truck conversion at that point in time (in 2003/2004). If I needed help from the local GM dealer, I wanted them to be able to use their routine troubleshooting resources to help. I knew that custom wiring, custom ECM/TCM, mismatched wiring and mismatched circuits would make it nearly impossible for another person to help. And lastly, I wanted this conversion to look as neat and professional as possible.

    Jim
    Last edited by More Power; 08-24-2009 at 20:03. Reason: add to

  7. #7

    Default

    Ok, after hours searching, I managed to get my instrument clusters working. It was some grounds, that werent connected. Of course, now it works when ever wants, so some more problems to search for. Now I´m stuck again, because of the fuel pump. I have the suburbans fuel pump, but no duramax one. Where should it be located? I checked the fuel tank, but there was only the level indicator and in the tank there were going only 2 wires (purple and black, probably for level indicator). I have alldata opened, and it shows, that both cars have same colour fuel pump wires (grey and black), but I cant find any available connector in my duramax harness. I used all duramax harness (C3 and C4) under my car. Of course, one opportunity is to make new harness, going from fuel pump relay to the fuel pump, but why to invent something, that should already be there? The alldata shows this diagram:
    http://stuff.e30club.org/images/subu...el_control.gif

    Also a quick question, how the tail lights should work? There is going 4 wires in, but theres 3 bulbs, each with two strands (or how it is called in english). I sorted out the right wires from Duramax harness, but now idea, how to connect them with suburban lights.
    Last edited by Margo_325; 04-27-2009 at 02:46.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •