It's Time to SUPERSIZE Moby - MoTech 6.2L LS Jeep Motor Swap

Maybe it would be convenient to splice in a manual fan over-ride, so that IF this happens again down the line, you can just flip a switch and keep the fan on.
 
That's not a half bad idea, I don't see why Jeep / motech (I don't know how that's all controlled / if motech even has access to such low level functions) decided to shut the fan off if there's no tach reading, as opposed to keeping it on if there was no tach reading. Seems like an easy solution to a poorly designed / programmed fault (again, not blaming anyone, I just can't see how someone in the programming department decided that would be the best way to handle the situation. Just seems odd.

Hopefully it all gets sorted out!
 
Isn't it just a "hall effect" sensor? If so, then shouldn't there be a distance that it should be spaced from the reluctor ring? Motech should be able to tell you that. Get under there with a feeler guage and see if the sensor is where it is supposed to be, if not, there should be "some" adjustment. If Motech suspects the sensor, then that should be the first step.

Jack
 
Isn't it just a "hall effect" sensor? If so, then shouldn't there be a distance that it should be spaced from the reluctor ring? Motech should be able to tell you that. Get under there with a feeler guage and see if the sensor is where it is supposed to be, if not, there should be "some" adjustment. If Motech suspects the sensor, then that should be the first step.

Interesting to see what the fix is.

Jack
 
If it just an adjustment I would think it is too far from the reluctor. If I remember right it should be the thickness of a matchbook but I can look in my notes if you need Eddie or Robbie probably gave it to you already. The fans are controlled by the original jeep can-bus system through the TIPM or fuse block and needs the tach signal to operate correctly. If I know Robbie his new integrated controller he built and makes these installs simpler is going to be used for running the fans by providing the can-bus engine data from chevy side to make the jeep side happy and eliminating the need for the tach sensor and reluctor wheel.

And yes you could make the fans a independent system but that would require more wiring, another controller, more power distribution and one more system to go down. It would be really nice if the gm side handled more of this and most likely will with time. The systems are similar how they work for the end result but the code to run them are completely different! Also check your balancer to make sure it hasn't loosened and is hitting the sensor. He probably pinned it to the crank but mine came loose using the GM installation tool! After re-tightening it has not loosened one bit. I wedged the flywheel through the inspection hole and used a 1 inch breaker bar and all 190 pounds against the frame to get it tight. Any help I can give Eddie just ask! I have a ton of notes, emails and texts from Robbie to help if needed!

Was -30 this morning with a windchill in the -60's and the little 5.3 didn't miss a beat! Everything else growled for a while though!
 
Agree what jim said. Just plain bad luck.
I have been running mine with no issues. Make sure the sensor is placed correctly and tight.
 
Was -30 this morning with a windchill in the -60's and the little 5.3 didn't miss a beat! Everything else growled for a while though![/QUOTE]

Wow, -30! I think you could run without any cooling system this part of the year.:cheesy:
 
LOL!! Thanks for all the tips guys but we got it covered. It's really not that big of a deal, just a gremlin that needs to be worked out and I only posted it up so that there is a record of it for those who are interested in doing this swap. Just keeping it real.

I should note that before taking our Jeep to Motech, we were having a variety of electrical issues including getting the tach and fan to work properly. At the time, they were telling us to cut wires on his kit to make it work and that's when we decided it might be best to just take it to him. Apparently, one of the things that wasn't set right was the crank position sensor and they were very quick to point that out. Needless to say, they were the ones who made the last adjustment to it. For whatever it's worth, the problem has only happened 3 or 4 times and isn't easy to reproduce. Heading up I-80 over the weekend got it to do it twice when the transmission dropped a couple of gears to maintain our speed. Restarting the engine got everything working properly again and we haven't had any problems since. I've talked to Robbie and we'll be going down to see him on Friday. He said he was more than happy to give things a look and address whatever needs to be addressed.
 
LOL!! Thanks for all the tips guys but we got it covered. It's really not that big of a deal, just a gremlin that needs to be worked out and I only posted it up so that there is a record of it for those who are interested in doing this swap. Just keeping it real.

So with everything that has happened, do you believe that this can be done by someone who has the tools and mechanic ability? Even at home or if they own a garage
 
So with everything that has happened, do you believe that this can be done by someone who has the tools and mechanic ability? Even at home or if they own a garage

Honestly, I don't know. The kit as I got it? Probably not or at least, not without a lot of support from Motech. Getting the motor in and parts installed is one thing. Getting everything to work is another. Even at that, ORE and/or I had to exchange a lot of texts and emails with Robbie to get it close and still, in the end, we had to send off our Jeep to Motech to have them get it running right. Granted, I'm sure that there are plenty of people who will say that we just didn't have the right tools or are not mechanically inclined and what can I say, they might be right. Having said that, I'm not sure what version Motech is on now but, I know they have made a lot of improvements to their kit and I would imagine it's a lot better now. I just don't have any experience with it so I couldn't say for sure.
 
Honestly, I don't know. The kit as I got it? Probably not or at least, not without a lot of support from Motech. Getting the motor in and parts installed is one thing. Getting everything to work is another. Even at that, ORE and/or I had to exchange a lot of texts and emails with Robbie to get it close and still, in the end, we had to send off our Jeep to Motech to have them get it running right. Granted, I'm sure that there are plenty of people who will say that we just didn't have the right tools or are not mechanically inclined and what can I say, they might be right. Having said that, I'm not sure what version Motech is on now but, I know they have made a lot of improvements to their kit and I would imagine it's a lot better now. I just don't have any experience with it so I couldn't say for sure.

So I'm guessing you would recommend having Motech do the work? Just because of the complexity of the kit
 
This might sound stupid and trivialize the process... but is the complication with switching motor brands making the GM motor work with the OEM Jeep computers? Would these type of swaps be aided if you just got rid of the OEM Jeep parts? Ran custom gauges, etc?
 
LoPo the simple answer is no and the complicated answer is yes! Depends which end of the build you are on! Completely re-wiring the jeep to get rid of the TIPM, ECM and BCM modules on the jeep CanBus does not come across to me as a bitchin time and that is coming from someone that re-wired my jeep with stock harnesses from an engine fire just to get things to work again! To be honest if you have NO desire to learn how the Can-Bus or the wiring works pay the extra money and have Robbie do it! He is getting the kits better but trust me here it is very difficult to make such a complicated kit so simple ANYONE could do it. I'm not scared to try almost anything and if I am at a complete loss that just feeds my fire more to learn it! If you are creative and will make the time to do a kit and keep it fun then by all means go for it! The first time does suck but now I would do it again and have thought of doing it for others! But right now that has been just a thought! One other reason not to gut the jeep side is I have seen one that was done that way! He played hell for two years to sell it! Scares the masses when you see too many things changed! Most non motor heads don't even notice what was done but they notice the tires and lift!ImageUploadedByWAYALIFE1389130271.305771.jpg
 
Jeep came out of an auction on Stanton Island NY. Paperwork left in jeep was from a gal out of New Jersey. After pulling it apart transmission oil was severely burnt leading me to believe boiled transmission oil out dipstick onto hot catalytic converter. There is an update to put jeep in limp mode if oil gets to hot but is not mandatory recall. I'm guessing this jeep did not have it done. Snorkel let fire get to soft top but did not burn interior. Bought it cheap so this was the best way to learn all about a jk. Just couldn't put myself to buy a perfectly good one then tear it all apart. Good way to learn but now I would have no problem pulling a good one apart! Eddie how has your mileage been now that you have some miles on it? Curious with the stock tune in it. Mine still needs tweaking just need time to make a box for air cleaner and seal it up since the MAF is very sensitive and I have double to one and a half times greater MAF temps then actual air temp because of the under hood heat.
 
And my exhaust is black! Been asking around with several tuners and most think incomplete combustion which can lead to one thinking it is rich. Makes sense since my Long Term Trims look good and exhaust temps are normal. Motor may have a little confusion going on since all the tables rely heavily on MAF readings and my temps are so out of wack!
 
This might sound stupid and trivialize the process... but is the complication with switching motor brands making the GM motor work with the OEM Jeep computers? Would these type of swaps be aided if you just got rid of the OEM Jeep parts? Ran custom gauges, etc?

I think jim about summed it up best. Being that you're in NV, you do have a lot more options though. Mel pretty much ripped everything out of EVO 1 and is running his HEMI running a manual shifting auto transmission and basic gauges but then, it is a race rig.

Eddie how has your mileage been now that you have some miles on it? Curious with the stock tune in it. Mine still needs tweaking just need time to make a box for air cleaner and seal it up since the MAF is very sensitive and I have double to one and a half times greater MAF temps then actual air temp because of the under hood heat.

Better now that we've put on some real miles on it. At first, we literally could see the fuel gauge drop as we drove - maybe got 8 MPG. Now, we are seeing more like 11-12 MPG and that's with us driving like we always do - not exactly slow. Needless to say, it's not all that better than what we were getting with our old 3.8L motor but, we have a hell of a lot more HP and torque. Of course, I suspect that if we were to drive more conservatively, we would be getting better.
 
At first, we literally could see the fuel gauge drop as we drove - maybe got 8 MPG. Now, we are seeing more like 11-12 MPG and that's with us driving like we always do - not exactly slow. Needless to say, it's not all that better than what we were getting with our old 3.8L motor but, we have a hell of a lot more HP and torque. Of course, I suspect that if we were to drive more conservatively, we would be getting better.

I don't feel so bad now, I am seeing basically the same numbers with the 6.4 Hemi. 10.5 to 13mpg pretty common depending on the road and wind conditions. I can get between 13-16 if I slow down and set the cruise at 63-65mph but who wants to do that.
 
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