Cummins Swap First Start! Plus Wiring a Computer-Controlled Engine [Part 17]

hello and welcome to the channel my name is waldo and this is the video that many of you have been waiting for we're going to be starting this common swapped gmc c3500 hd for the first time and to make it that much more challenging my goal is to do it with the ignition key here it is my 1995 gmc c3500 hd i paid 300 for this truck essentially saving it from being scrapped this project has turned into a full-on restaurant complete with a paint job and custom seats the engine is a 24 valve 5 9 cummins out of a dodge ram the transmission is a five-speed eaton fuller out of a medium duty freightliner [Music] the goal is to end up with a heavy duty truck for towing and hauling future projects i even convert a cable-operated clutch release mechanism to a hydraulic clutch release for ease of operation in my last land rover project video i mentioned that i lost some footage for that project unfortunately i also lost some footage for this project however for this specific video i didn't really lose that much footage i'll quickly walk you through what i've done so far one thing i did is i installed a new fan belt this one i think is about 88 and a half inches long which is longer than the one that came on the cummins and the reason for that is because i've installed the gm alternator here and it's mounted in a slightly different position than what came on the dodge i also installed a nice new starter this is a delco 29mt now there was a starter that came with the flywheel housing and the transmission that i bought however it didn't fit here because the frame rail was actually in the way this is the denso starter that came with the transmission and the motor here juts way out to the side didn't you test fit it no i didn't have the starter installed while i was test fitting the engine i wouldn't have been able to make it fit anyway because there isn't enough room for me to move the engine up or to the left so at this point in order to get this thing going the main thing i need to do is a bunch of wiring before i can do that however i need to reassemble a bunch of the body panels on the front here that hold the wiring in place like the fender liners the fenders themselves and probably the radiator support as [Music] well [Music] so [Music] you know i think i'm getting a little bit ahead of myself here this big messy wiring harness is comprised of some wires that are going to be staying here because they power things like the lights the horn the abs but a lot of it is for the old engine and it needs to be removed i think what i need to do is remove this harness completely pull it apart and separate out the things that are staying and the things that are being removed from the vehicle i've never actually done an engine swap before and both this 24 valve cummins and the gm 6.5 diesel that was in this truck originally they're both computerized engines and they both have a lot of wiring because i've never done anything like this before i don't really have a process even as a computer engineer it's a little bit of a daunting task because it's like where do i start there are so many wires here i just got to rip these you know harnesses open and figure out what wires or what go one wire at a time and i think it's going to be a lot of work but i know i can get it done later i am so glad that i removed this harness from the vehicle and brought it inside to work there is no way that i would have been able to get all this work done with the harness inside the vehicle as realistically it wouldn't be possible as an added bonus it's also quite comfortable in here as for the harness itself i've already removed most of the wires that go to the gm engine and most of the wires that go to the gm transmission i've set those aside so that if i do decide to use that engine or transmission in a future project i should be able to rewire it up without too much difficulty what's left over here in the middle is mostly stuff that's going to stay in the vehicle you can see here these went to the transmission and then this bundle of wires went to the engine over here is the engine compartment fuse and relay box that's going to be staying in the vehicle and that supplies all the power to stuff this connector right here is one of the connectors that goes through the firewall this goes through the firewall on the driver side of the vehicle and then this connector over here goes through the firewall on the passenger side of the vehicle i still have a bit of work to do on this part of the harness because these three connectors go to the gm pcm which is not staying in the vehicle i guess i should probably talk about what i'm doing as far as the computers now this is the gm pcm and this is coming out of the vehicle and it's not going to be used on the other side here is the vssb vehicle speed sensor buffer and this is actually going to be staying in the vehicle the reason for that is because this takes an alternating current speed signal from the transmission and converts it to the signal that's used by the speedometer in the instrument cluster so this is going to be necessary now while the gm only has a single pcm that controls the engine and the transmission the dodge on the other hand has an ecm and a pcm an engine control module and a powertrain control module the ecm i believe was made by cummins and it specifically controls the engine whereas the pcm was made by dodge and that controls other things like the cruise control and it interfaces with various gauges and other stuff like that in this common swap i'm going to be using both the ecm and the pcm from the dodge i still have a lot of work to do on this part of the harness i have to remove these three pcm connectors so that if i want to use these on a future project they'll be available for that i was really dreading the wiring portion of the project but once i started it it really wasn't that bad do you have any tips for the viewers yeah develop a system of organization and take it one wire at a time also make sure you have good wiring diagrams don't expect to buy a haynes or a chilton manual and use the included wiring diagrams because they're not good enough i purchased an all data diy subscription and that gives you access to the factory wiring diagrams which are pretty good much later all right and here is the dodge wiring harness now these three connectors over here go to the pcm these two connectors go to the engine wiring harness and the ecm and this bundle of wires over here this used to go to the junction box on the dodge what i've done is i cut off this connector right here and then labeled all of these wires i have to say the dodge wiring harness was super easy to work with i will not hesitate to do another 24 valve coming swap props to chrysler for doing such a good job on their wiring this single bundle of wires this is what goes to the rest of the vehicle so this is where i need to make all of the connections another nice thing about this harness that differs from the gm is that almost every single wire in this is a different color the gm on the other hand they use a lot of solid colored wires which means when you have a big bundle of wires there'll be a bunch of wires that are the same color in that bundle because almost all of these wires are unique it made it really easy to go through and figure out what each wire does so that i could label these all right i am going to mount the dodge pcm right here and the reason why this is important is because this is what determines the position of the dodge wiring harness relative to the gm wiring harness that's important right now because i'm going to connect them together outside of the vehicle and i want to make sure that i get all the connecting wires the right length so previously located in this space was the gm coolant expansion tank i'm not going to be using it because it works a little bit differently from the dodge system and i am using the dodge radiator and obviously the dodge engine so i think it makes sense to use the dodge coolant expansion tank now that's located up here pretty close to the radiator which frees up this space so that's why i can mount the pcm here all right so we're going to get what's left of the gm wiring harness sort of in place here this side doesn't really matter so much i think what matters is that i get this side in place [Music] all right so that's about where that goes [Music] so what i need to know is where these meet which is gonna be right uh actually these are gonna need to come up a little bit to avoid the exhaust so these are gonna meet up right about here make sure i pull all these tight i'm just going to tape these together maintain their position and then all the stuff over here it ends up wherever it ends up it'll be fine all right i have the harnesses back in the house and it is time to start soldering these connections together i am not going to film soldering all of these wires together however i am going to film one of them and this one happens to be the control wire for the injection pump relay so this wire comes from the pcm and this wire goes to the relay box i labeled both of them number 38 to show that these get connected together and the wires coming from the dodge wiring harness are plenty long enough i have more than enough extra wire here so that i don't need any extra wire to connect the two so i'm basically going to make sure this wire is running along the existing gm harness make sure it's the right length it's going to end up about like that and then i'll cut it here leaving a little bit of overlap and we'll go ahead and strip these i think this is 18 gauge wire i'm going to strip off half an inch to three quarters of an inch now before i forget because i'm really good at forgetting i'll slide some shrink wrap over one of the wires get it out of the way and then a little trick that i like to do is i take each of these and i kind of fray the edges do it on both sides and then i stick them together and i do a little bit of twisting and what this does is it creates a loose mechanical bond it doesn't have to be perfect but that'll at least hold them together so i can solder them grab the soldering iron now we have a beautifully soldered connection that is going to last a long time take this heat shrink and slide it over and then we can use a heat gun to shrink the shrink wrap beautiful much much later i have made almost all of the connections and i'm just about ready to install this in the vehicle i still have a few wires right here that need to be connected and i have a few wires over here as well right here in the middle the harnesses are already combined and i have to say it's looking pretty good like almost professional over here on the other end i ended up needing to add six relays just to make everything work the reasons for that are complicated but it is what it is in a nutshell the circuits on the dodge are generally ground switched while the circuits on the gm are switched on the power side using relays is an easy way to convert from one to the other i did manage to use two relays from the relay box as well i know it doesn't really show in the video but it has taken me days to work on this harness it's just one of those things where it takes quite a bit of time to do things the right way but in the end it'll be totally worth it all right so it is time to mount the pcm now the pcm mounts to this bracket and i'm going to adapt this bracket which is meant for the dodge to mount here using these two bolt holes for the coolant reservoir so i got to drill a couple holes in this and then cut this part off and these look like they're about seven inches on center so seven inches is about that long and really i can place this fairly arbitrarily because i have a lot of wiggle room my first hole will go there [Music] [Music] so fairly sturdy for only two points of contact this pcm really doesn't weigh very much so i'm not too concerned about that oh shoot you know i hope this isn't going to be in the way of the hinge for the hood if it is it's not the end of the world i could just drill new holes for this and scoot it over a little bit i'm going to worry about that later when it's time to put the hood on nice i have here the mostly completed harness and i'm ready to install it [Music] so the tricky part might be snaking this big mess of wires through here i got it like a pro all right let's talk about some of the connections that i have not made yet these generally fall into the category of connections that were difficult or impossible to do while the harness was outside of the vehicle this thingy right here that's a technical term is the thingy that controls the vacuum for the cruise control this is going to be mounted right around here on the driver's side wheel liner also to be mounted over here on the wheel liner are the relays for the air intake heaters here in the middle i have some wires that go to the transmission there are wires that go to the reverse switch and a twisted pair that goes to the vehicle speed sensor there's also this yellow wire which is going to go to the starter solenoid and i haven't yet figured out exactly how i'm going to route that but that's on the list of things to do over on this side of the vehicle the wiring harness splits apart to go to the pcm and to go down here through this grommet and through the firewall i have several wires going from the pcm through the firewall and i waited on these because i didn't know the exact positioning of these wiring harnesses these include wires for the obd2 port as well as a couple wires for the cruise control controls speaking of cruise control the gmc uses buttons and switches on this stock to control the cruise control the dodge on the other hand uses buttons on its steering wheel the controls on the gmc and the dodge are both designed to send signals to their respective pcms however the signals are totally different and are not cross-compatible as a result there's no way to connect the gmc controls with the dodge pcm with simple wiring and have it work i plan to address this in a future video because it is important for me to have a polished build here where the cruise control works the solution is going to require a circuit board and some complex circuitry to make it work i want to take a moment real quick to talk about twisted pairs of wires now this wire right here is the wire that goes to the vehicle speed sensor on the transmission and this over here is the original wire which is not long enough to make it all the way back to the transmission so i had to extend it now when you extend a twisted pair of wires make sure that the new wires are also twisted in the same direction as the original wire now the reason why these wires are twisted is because it greatly reduces the wire's sensitivity to electromagnetic interference the speed sensor on this vehicle is an inductive type sensor and it sends a very precise sine wave over the wires any electromagnetic interference could ruin the speed signal now to make this twisted pair i simply twisted it by hand and then because it wanted to unravel on its own i went ahead and clamped it to something to hold it taut like this once i had the wire held in this position i just took a heat gun and i heated up the whole length of the wire melting it just a little bit and the goal was to slightly change the molecular structure of the insulation so that once it cools it'll stay in this position so well let's find out if it worked yeah that's not too bad it wanted to unravel just a little bit but this is totally usable right here this is pretty good [Music] nice [Music] so i've identified a little issue here the abs module is in the way of the air intake now i thought when i mounted the engine that i did leave enough room for that but apparently not luckily i think there's enough room in between the windshield washer fluid reservoir and the abs module for me to modify the bracket and move it a couple inches this way all right check it out i modified the bracket i extended it a bit on this side cut off a bit on this side drilled some new bolt holes and hopefully i cut out enough and hopefully it'll work without any further modification because i already put some paint on it and i don't want to have to do that again so i got it in and it fits great i probably have about an extra half inch more than i need that's what she said [Laughter] so i have made some pretty decent progress so far i've mounted the battery trays and this one also has the integrated battery sensor this is the dodge sensor that goes to the dodge pcm underneath the battery tray i mounted the cruise control vacuum solenoid and then over here underneath the abs module i mounted the air intake heater relays i also got all these things wired in nicely i also managed to get the dashboard reinstalled integrated into the dashboard is a lot of wiring that's critically important for running the vehicle so that's why i had to reinstall this as for doing the common swap itself i don't think i actually had to modify any of the wiring that's part of the dashboard the only wiring under the dash that i have had to modify is wiring for the trailer brake controller and also for the gauges that i'm currently working on installing speaking of gauges i made this really cool custom gauge pod out of fiberglass i really wanted to add four gauges to this truck and there's just not really a good way to do it a lot of people go with a mounting solution where they mount their gauges on the a-pillar i've never really been a huge fan of that and also it seems like the maximum number of gauges that you can mount on the a-pillar is three so i decided to build this and it turned out pretty well don't mind this gauge on the end here which is not fully installed yet the gauges i chose to install are a fuel pressure gauge a boost gauge a pyrometer and an oil temperature gauge unfortunately as i mentioned before how i lost some footage this is one of those things that i lost all of the footage for and it's really unfortunate because it's pretty cool how this thing was made well it has taken me a long time to get to this point but i think i'm about ready to start it up i've topped it up with oil i have the batteries connected i went ahead and hooked up the intercooler along with the intercooler hoses that go to the intake and to the turbo and i also installed the dodge air box so that i make sure i get nice clean air going into the engine i'm really nervous about this because who knows what could happen it could catch on fire it could blow up but here we go so i guess we'll connect to the batteries here there's the first one and i don't see any smoke or fire yet both of these batteries have disconnects yeah everything looks good so far so let's try starting it up oh and one other thing i should mention is that i installed a new power steering pump and i think the instructions said to make sure you don't run it dry so i filled up the reservoir topped it all the way up with power steering fluid but there's a lot of other stuff in here that needs to fill up with fluid as well so i'm only going to be able to run it or crank it for a short period of time before i stop and then top off the reservoir but then again i'm not going to be able to run the engine very long anyway because i haven't installed the radiator or any of the cooling system including antifreeze so so i have all the gauges installed except for the oil temperature gauge which is not hooked up on this end but the other ones are hooked up the tachometer should work the rest of the gauges probably won't work so let's give it a try all right that's run we got the weight to start light coming on so that's a really good sign because that's controlled by the dodge pcm i believe low coolant light is on that's expected i don't know if the engine is going to have any fuel in it so it might have to crank over a little bit i might have to bleed the injectors too it works that's excellent let's take a quick look around here just make sure everything's good oh as for the exhaust because everyone likes to see exhaust i don't have a downpipe installed all it is is the exhaust brake here coming off the turbo so the exhaust is going to be coming out there and kind of just going downwards so we'll see what it looks like i did try fitting the dodge downpipe and it didn't quite fit so that's going to require some modification but that'll be for another video all right let's give it a go okay turns over pretty strong i think i probably need to bleed the injectors but this is actually good because this gives me an opportunity to make sure that the power steering pump doesn't run out of fluid i'm going to try bleeding the injectors here all right i already got fuel coming out of here so i'll tighten this up click click did you use a torque wrench on that nut you heard it didn't you click click we'll give it a little bit of time to let the starter cool down but in the meantime i have to say i'm very happy that the starter works i wasn't really sure if i had the correct starter but everything seems fine see if i can watch this one while i'm cranking it over yep i can see fuel coming out so one of the things that i love about diesel engines is that they're really simple all they take is fuel air and compression in order to work now in this case we know it has air we know it has compression so fuel is the missing element are you aware of the irony of the situation yes that's really weird all right it is the next day and not only did i charge the batteries up overnight but i also found an issue that would definitely prevent it from starting i noticed on my obd2 scanner that while cranking the engine it read an rpm of zero and obviously that doesn't make sense because as the engine is turning it should read some low value so in order to determine the rpm the computer uses the crankshaft position sensor so that's where i'm going to start looking to figure out the issue what i did was i went ahead and unplugged the sensor and i noticed immediately that the contacts of the sensor and of the connector were quite dirty it was caused from sitting unplugged for a while not really a big deal so i went ahead and cleaned them off and while i had it disconnected i verified that the sensor was getting ground and plus five volts as an input i went ahead and plugged the connector back in cranked the engine over and the obd2 scan tool did show that it was reading an rpm so that fixed the issue so now i guess we just have to crank it some more and hopefully it'll start up but i guess we'll find out if there are any other issues well here goes nothing let's give it a try should we wait for the weight to start light to turn off i guess so all right yes it sounds great i'm gonna take this opportunity to check the power steering fluid and then once that's good uh we'll start it up again so the power steering fluid level looks good i want to start it up and run it for a little bit longer now [Music] [Music] did you hear that turbo whistle also the tachometer worked how did you get the tachometer to work that's what the gm alternator is for it has a four wire connector on the back and one of the wires outputs a phase signal which runs the tachometer the pyrometer already went up to over 200 degrees so that's cool to see that working with this project milestone completed we are a lot closer to getting this truck on the road i think next i'm going to work on getting a drive shaft for the truck i also need to reinstall the interior including a nice new carpet and a new headliner if you're new to the project you can binge watch the whole build series from the beginning by watching this playlist up here in the corner thank you so much for watching and please feel free to leave your questions and comments down below i'm sorry next question please i'm not under oath am i

Channel: Waldo's World

Views: 109,815

Keywords: Cummins swap, diesel swap, first start, engine wiring, project truck, GMC C3500HD, 24-valve 24V Cummins, GMT400, DIY

Id: 4HCYn0thibw

Length: 27min 17sec (1637 seconds)

Published: Mon Mar 22 2021