Diesel Conversion Cummins 4BT

Looking for advice on these diesel conversion Cummins 4BT

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Brosky, I will probably be walking away from this machine but before I do that I will enjoy it for a little and like I always do spend some money on this machine... I will enjoy it for sometime. My next FJ80 will be a stick one. Thanks.....
 
FS85 said:
Brosky, I will probably be walking away from this machine but before I do that I will enjoy it for a little and like I always do spend some money on this machine... I will enjoy it for sometime. My next FJ80 will be a stock one. Thanks.....
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FS85 said:
MCT.... this is the vehicle that was in Birmingham. I bought from Mike sight un-seen, pretty crazy. I was not in this forum before the purchase but now I am, game changer. What were folks in this forum saying about this vehicle ? Curious to hear some feedback. There weren't too many bidding on it. Only one person was trying to outbid me but he eventually stopped. Thanks
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Buying FJ80 Diesel?!?
 
FCT, I will be selling my FJ80 diesel later, would I buy another FJ80 diesel... maybe a factory diesel, preferably will go with the gas motor and keep it stock.
 
i really hate to see a vehicle get passed around so much. I remember it being on E-bay almost 5 years ago and just about loaded up to drive to CO to take a closer look i'm pretty sure it's the same one. at that point the hood didn't even close all the way after the air to water cooler was added. it looks like someone added the second tank and external fuel heaters meaning they were probably looking to run alternative fuels like WVO SVO and BIO diesel so they could preheat and purge.

i'll take some pictures of my damper location you'll have to see where the engine sits in relation to the front cross over supports to see if there is room for the damper. up front. if anything it's mass to help with vibration. there is a fluid damper that is suppose to do more than the dodge rubber version but it is pricey you'll have to search 5.9 6bt performance stuff. basically most things that fit he 6bt fit the 4bt. my set up has a 70lb flywheel aft then a flex plate for the torque converter.

stock style damper like i have on the shelf I'll sell for $80 shipped has mounting bolts as well: Vibration Damper Stock Replacement Dodge Cummins 1996-1998 5.9L

Fluid damper performance there are a few types for different tach pickups but your probably not using that feature since you don't have a damper to start with: Fluidampr Performance Diesel Damper for 1992-1998 Dodge Ram 5.9L Cummins 12V | eBay
 
CJ, I'm with you. This conversion was done in Colorado by Proffitt Cruisers. I spoke to the owner and he remembers this conversion. This is a hard core Overland vehicle, I will try it out for sometime as a hobby, keep adding to it and after sometime put it on the market for someone who is more of a overland enthusiast than me. I will be meeting with several mechanics in New Jersey and if I can use the damper I will reach out to you. Thanks for all your guys help.
 
I know of another one of these exact conversions which has had issues with the motor mounts and vibrations. One of the problems they had was a failed motor mount which resulted in pinched trans cooling lines and a toasted transmission.

As @beno noted, you may want to cut your losses and go for a stock truck, diesel or petrol.
 
Boys... whoever does not understand this world why are you in this forum. You are sounding like my wife asking why, why, ... people that do not enjoy and are passionate about this world do not understand why we do what we do .... this is a hobby and a passion, we all find enjoyment in what we do.

Cyclosteve.. I will mess around with this rig for a while and enjoy it for what it is. Thanks boys
 
Sorry, most of us come off as miserable SOBs because we are. You'll get there soon!
 
MCT, everyone seems to be very cooperative, I guess you can have a bad apple every know and then. .... I will continue to be me, not an SOB ... thanks
 
Here is a link to a short video I took today and posted it on YouTube. Feel free to comment ...Thanks


 
Thanks for the video! It is kind of deceptive in the video it doesn't seem too bad, but you can tell it is a little loud. Is there an odd vibration coming from the shifter, sounded more metallic? I think like you said, you have the truck, spend a little money on it and see if it starts becoming a little more to your liking.

I would start with unbolting the front 2 seats, and shift console and center console, should be a total of about 17 bolts. 4 on each seat, 5 on the center console and 4 for the shift console. The transfercase knob just unscrews and you need to put the shifter in N and the shift console lifts out. Then the dead pedals on both sides and threshold caps, then pull the carpet back.

Get good solid products like:
Sound Deadeners Showdown Tiles - CLD Tiles™ | Sound Deadener Showdown
Second Skin Luxury Liner Pro - Luxury car quiet with our noise insulation products Luxury Liner™ Luxury Liner Pro™ | Second Skin Audio, Made in the USA.
Second Skin Spray Adhesive - High Temp Spray Adhesive

Clean up the area as high up on the firewall as you can reach and as far back on the floor as you want to go. Lay down the Sound Deadener Tiles, be thorough and cover it all. Use a wooden roller to press it hard to the floor.

Clean up the metal backing on the tiles with alcohol and then spray the adhesive on the tiles and Luxury Liner Pro and get it as far up on the firewall as you can and as far back on the floor as you want. Couple of things to be careful about, watch the thickness around the pedals, dead pedals, bolt holes for the seats and thresholds.

Button everything back up.

Open the hood and pull the hood lining, make sure you have extra push pins on hand because they will certainly break. Clean under the hood and cover under the hood with Sound Deadener tiles.

The more time you take cleaning things up and getting the best coverage possible will determine how good it helps with the noise.

I would start there, probably cost you about $150-175 and a day or two on a weekend. But could be a big determining factor on whether you can quiet the truck down to something you want to live with. If this helps, then I would start looking at the mechanical aspect with the vibration dampener and engine mounts.
 
Like @beno said it's time to punt. You have to love everything about the 4bt to enjoy it. If you didn't smile the first time you started it up and drove it you never will. I have seen that truck for sale over the years so maybe it's an odd duck from a normal 4bt conversion? When I talked with Proffitts about doing a 4bt swap years ago they were honest about the negatives of it.
In my opinion a manual trans should always be behind a diesel. Maybe it's random but most 4bt swaps that are for sale are autos.
 
when does the torque converter lock up? id say you do not have a very high stall based on the video you seem to be running a lot more RPM than i would expect. there seems to be some wind noise? is your sunroof closed all the way. i heard a metallic sound as well as mentioned that does not sound normal exhaust hitting some where? with higher stall increase your idle. it will help low end vibration. what Turbo? pyro numbers? i've played with turbos and have struggled to find a universal application like the "hx35" on the 6bt. ive run 3 separate hx30 40 44 46mm comp inducers.all seem to fall off on the top end. current is the super 46mm which gets me to about 3k which you are at allot meaning bad fuel economy

a video i made trying to explain details about my trans controller but shows engine details and noise stuff too
 
CJ, thanks for the explanation and the video. Are you part of any local land cruiser club or Overland club in the area. Where do you guys go to test the performance and capabilities of these vehicles. Thanks
 
Mr Cimarron said:
Like @beno said it's time to punt. You have to love everything about the 4bt to enjoy it. If you didn't smile the first time you started it up and drove it you never will. I have seen that truck for sale over the years so maybe it's an odd duck from a normal 4bt conversion? When I talked with Proffitts about doing a 4bt swap years ago they were honest about the negatives of it.
In my opinion a manual trans should always be behind a diesel. Maybe it's random but most 4bt swaps that are for sale are autos.
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i love my auto but it's been a love hate for sure. until i could control it with a standalone with infinite control i would have agreed. you manual people get better MPG for sure. my buddy has a 94 dodge 3/4 manual 4wd with 4bt and 35" tires pulling about 20mpg at 80mph on average which would be about 18mpg with the 6bt if not lower depending on tune. you have to remember people talking 20+ are in small compact trucks with no weight and 2... something gears at 60mph. if it sounds to good to true it is. i got 22mpg out of my stock 98 6bt at 65-70 for one tank in 4 years because i could not get myself to drive that slow for the rest of the time. 19mpg was pretty normal for 75-80mph. and i loved it even though it gave me headaches due to noise just like my 4bt does after at few hours. my dad's 05 common rail does the same. at speed they all sound the same and are not as quite as a gas motors.
 
FS85 said:
CJ, thanks for the explanation and the video. Are you part of any local land cruiser club or Overland club in the area. Where do you guys go to test the performance and capabilities of these vehicles. Thanks
Click to expand...
FS85 said:
CJ, thanks for the explanation and the video. Are you part of any local land cruiser club or Overland club in the area. Where do you guys go to test the performance and capabilities of these vehicles. Thanks
Click to expand...


here in kansas city we have local club TAC and some parks with in 2-3 hours some private some public. all super family oriented. while i daily drive mine when i can i have a back up as well. planing a big CO overland trip with my family a small herd of dual sport bikes next summer. cruiser and off-road trailer providing chase truck duties for gear
 
Seeing as how you own the 80 and aren't looking for advice on whether to buy it, I fully agree with having some fun trying to sort it out and then wheeling it. Disappointing builds happen everywhere and every day with every kind of vehicle. It is most often a disappointment because the builder didn't get it quite right due to lack of funds, skill, time or patience. A very small few come out really well because most can't conquer these problems.

The good news is that all is not lost. As the new owner with new determination, you can pick up the torch and bring the project to a positive end, and with help here (and there are many who have done these conversions well) it can be a positive endeavor.

Looking forward to seeing your progress.

Oh, and a welcome to mud salute :flipoff2:
 
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