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Any updates? I'm watching closely as I'm going to take on an OM617 swap soon. My skills are super limited, but I'm going for it.
-Daniel
-Daniel
- Thread starter
- #44
Apologies for leaving folks hanging if they have been following, but am having issues posting and editing pics. As others have noted, the main clearance issue for this swap is the oilpan of the OM617, as it is a forward sump and FJ40 pumpkins are girthy (not to mention old FJ40 springs tend to get pretty flat...). But, the combination of modifying the oilpan, swapping to a Toyota mini-truck axle and installing 2' Rancho lift springs, I now have enough clearance. If you stick with the stock FJ40 front, Id estimate that you will need at least a 4" lift to accommodate the merc diesel. Too high for my preferences, but I like em low and slow.
I painted the oilpan machinery gray so that I could spot leaks:
![IMG_0373[1].JPG](https://forum.ih8mud.com/attachments/img_0373-1-jpg.1495751/ "IMG_0373[1].JPG")
![IMG_0372[1].JPG](https://forum.ih8mud.com/attachments/img_0372-1-jpg.1495748/ "IMG_0372[1].JPG")
I painted the oilpan machinery gray so that I could spot leaks:
Nice rims. Congrats on the oil pan welding. That can be finicky stuff to do it with no leaks when it's that thin.
Daner, there are cool repro t-stamped hubcaps available now. The guy is here on mud and also sells on eBay. They look amazing on those NOS black wheels IMO.
- Thread starter
- #48
Good to hear the hubcaps are still available, they do look great on a clean set of wheels. As for the oilpan welding, I cant take credit: I did the fabrication part and took it to a professional welder. I haven't filled it with oi yet, but it looks good. Certainly better than I can do with my old-school stick welder.
- Thread starter
- #49
I've been working out of town for the last few weeks so have been chomping at the bit to get home and get this thing running before summer ends.
And it is getting down to the nitty gritty. I ordered a throttle cable from Summit Racing (they ship quick!) and scored an FJ40 gas pedal from another IH8mud member (thanks!), so after a little fabricating and modification of the ridiculously complex Mercedes Benz throttle assembly, I think the throttle assembly will work ok. Same with the clutch assembly, the hardest part was finding an 11mm nut for the clutch master cylinder. hydraulic line. Seems that Toyota used some truly odd-ball thread sizes on early models... Still have some fabrication left on the brakes, but that is on hold until I swap the rearend from the stock FJ40 to the Toyota Mini-truck. No-not stoked to swap in mini-truck axles, but the 5-speed transmission/transfer case has a center output, which would create a pretty steep angle in a very short space if I stick with the FJ40 axle.
I also have plumbed all of the radiator hoses and the fuel line hoses. The lower radiator hose is very close to the alternator. I didnt have the alternator when I test fit the radiator/hoses...(fabrication learning experience #547, don't fabricate things until you have all of the pieces and know they will fit). The gas tank is a later model tank and doesn't sit well in the space. I don't have the seats to see if they will fit over the later tank, so, having just learned "fabrication learning experience #547", Ill hold off on mounting it permanently.
Hoping to wire it next weekend and hopefully be able to fire it up!
Was able to fit the Toyota five-speed under the stock transmission tunnel with only minor carnage: (still have to cut hole for the transfer case shifter).
![IMG_0738[1].JPG](https://forum.ih8mud.com/attachments/img_0738-1-jpg.1507113/ "IMG_0738[1].JPG")
And the throttle cable and clutch plumbing.
![IMG_0722[1].JPG](https://forum.ih8mud.com/attachments/img_0722-1-jpg.1507118/ "IMG_0722[1].JPG")
And it is getting down to the nitty gritty. I ordered a throttle cable from Summit Racing (they ship quick!) and scored an FJ40 gas pedal from another IH8mud member (thanks!), so after a little fabricating and modification of the ridiculously complex Mercedes Benz throttle assembly, I think the throttle assembly will work ok. Same with the clutch assembly, the hardest part was finding an 11mm nut for the clutch master cylinder. hydraulic line. Seems that Toyota used some truly odd-ball thread sizes on early models... Still have some fabrication left on the brakes, but that is on hold until I swap the rearend from the stock FJ40 to the Toyota Mini-truck. No-not stoked to swap in mini-truck axles, but the 5-speed transmission/transfer case has a center output, which would create a pretty steep angle in a very short space if I stick with the FJ40 axle.
I also have plumbed all of the radiator hoses and the fuel line hoses. The lower radiator hose is very close to the alternator. I didnt have the alternator when I test fit the radiator/hoses...(fabrication learning experience #547, don't fabricate things until you have all of the pieces and know they will fit). The gas tank is a later model tank and doesn't sit well in the space. I don't have the seats to see if they will fit over the later tank, so, having just learned "fabrication learning experience #547", Ill hold off on mounting it permanently.
Hoping to wire it next weekend and hopefully be able to fire it up!
Was able to fit the Toyota five-speed under the stock transmission tunnel with only minor carnage: (still have to cut hole for the transfer case shifter).
And the throttle cable and clutch plumbing.
Last edited:
- Thread starter
- #50
After two days in a row above 110 degrees, it only hit 101 today!
Cool enough to get a few things done, like rough in the plumbing for the fuel line. I'll clean everything when I mount it permanently, not too worried right now as I will be pulling everything out to paint the interior. I will need to figure out a better way to tie the return line into the ventilation tube of the stock FJ40 tank. For right now the rigged up 1/4 tee was the best alternative I could find in any of the local auto/hardware stores...yes, Im aware it is ghetto...(first pic) I'm open towards better ideas!
I am running a secondary fuel pump at the tank. In theory, this isn't necessary, but on my last diesel swap I found it really helps starting if you don't drive for a week or two or if you run out of fuel. Diesels can be ornery if there is any air in the lines and the extra electric fuel pump seems to solve that problem.
The other battle I've had is mounting the oil cooler. The lines from the Mercedes are formed to fit in a 300D, and are a real pain to fight into the tighter space of a Land Cruiser. I was able to wrestle it into place so that I can hopefully start the truck tomorrow or Sunday, but will probably splurge on custom lines.
![IMG_0753[1].JPG](https://forum.ih8mud.com/attachments/img_0753-1-jpg.1510434/ "IMG_0753[1].JPG")
![IMG_0752[1].JPG](https://forum.ih8mud.com/attachments/img_0752-1-jpg.1510420/ "IMG_0752[1].JPG")
Cool enough to get a few things done, like rough in the plumbing for the fuel line. I'll clean everything when I mount it permanently, not too worried right now as I will be pulling everything out to paint the interior. I will need to figure out a better way to tie the return line into the ventilation tube of the stock FJ40 tank. For right now the rigged up 1/4 tee was the best alternative I could find in any of the local auto/hardware stores...yes, Im aware it is ghetto...(first pic) I'm open towards better ideas!
I am running a secondary fuel pump at the tank. In theory, this isn't necessary, but on my last diesel swap I found it really helps starting if you don't drive for a week or two or if you run out of fuel. Diesels can be ornery if there is any air in the lines and the extra electric fuel pump seems to solve that problem.
The other battle I've had is mounting the oil cooler. The lines from the Mercedes are formed to fit in a 300D, and are a real pain to fight into the tighter space of a Land Cruiser. I was able to wrestle it into place so that I can hopefully start the truck tomorrow or Sunday, but will probably splurge on custom lines.
- Thread starter
- #51
On to the wiring-and it looks like the original 1965 wiring is a tad messy.
I think the way to approach the old wiring, at least for the time being, is to isolate the original wiring harness from the 6-8 wires required to operate the OM617, i.e the alternator, starter and glow plugs. That way if any of the old wires short, it will blow a fuse but won't leave me stranded. I hope.
If I understand it correctly, the mercy alternator (which has a three prong outlet I can't find anywhere-so be sure to save that part if you do a swap) only requires to 10 gauge wires to the battery and a smaller to an idiot light.
The big mess of wires is from a Nissan diesel truck I parted out. Snagging the wiring harness before junking was the best money-saver I've done as I when I replace or splice a wire on the FJ40 I have wire that matches, instead of making a confusing nightmare for the next owner.
I think the way to approach the old wiring, at least for the time being, is to isolate the original wiring harness from the 6-8 wires required to operate the OM617, i.e the alternator, starter and glow plugs. That way if any of the old wires short, it will blow a fuse but won't leave me stranded. I hope.
If I understand it correctly, the mercy alternator (which has a three prong outlet I can't find anywhere-so be sure to save that part if you do a swap) only requires to 10 gauge wires to the battery and a smaller to an idiot light.
The big mess of wires is from a Nissan diesel truck I parted out. Snagging the wiring harness before junking was the best money-saver I've done as I when I replace or splice a wire on the FJ40 I have wire that matches, instead of making a confusing nightmare for the next owner.
- Thread starter
- #52
I was hoping to try and start the motor today, but got called into work (on Sunday) so didn't get that far. Shooting to have it running, and hopefully driving, next weekend.
One observation: If I ever buy another half-finished project, I will low-ball them on the price. A half-finished project is not worth the sum of parts. The guy I bought the OM617 and Toyota transmission was a nice guy, and he did better work than most folks, but lots of small parts are missing. I can't figure out where other stuff goes, and I have no way of knowing if things are assembled and torqued correctly. Kind of thinking out loud, but also as advice to everyone else.
One observation: If I ever buy another half-finished project, I will low-ball them on the price. A half-finished project is not worth the sum of parts. The guy I bought the OM617 and Toyota transmission was a nice guy, and he did better work than most folks, but lots of small parts are missing. I can't figure out where other stuff goes, and I have no way of knowing if things are assembled and torqued correctly. Kind of thinking out loud, but also as advice to everyone else.
^^Following^^
Smaller wire on the alternator from what I could research takes at 3 watt bulb. I put a 3.1 watt light bulb on mine and alternator is running at 14.1 volts. The other two wires went straight to the battery.
- Thread starter
- #55
Almost wrapped up the wiring. I left the original wiring harness intact with the exception of replacing the all of the wires before the fusebox.
The wiring for the OM617 looks like it will be a cakewalk. I'll draw up a diagram after its done (and working) as I think I've pared it down to the bare minimum. I'm really stoked at the simplicity- it will be nice not having to worry about complex computerized crap.
First, had to take a step backwards and remove the radiator and rearrange things. By moving the radiator to the passenger side as far as possible (before hitting the headlight) I was able to mount the oil cooler next to the radiator on the drivers side. Fits perfect, almost like it was meant to be...the radiator is an unmodified FJ40 aluminum replacement. The stock Mercedes hoses attach pretty well, but it looks like ill need to shorten the top one a tad to get that bend out....
Back to work tomorrow, BUT, hoping to fire it up for the first time Saturday. Ill refrain from posting emojis until it starts.
![IMG_0768[1].JPG](https://forum.ih8mud.com/attachments/img_0768-1-jpg.1514306/ "IMG_0768[1].JPG")
And just to make sure the hood still closes with the alterations. Its very tight, but seems to be OK. Yes, I know, I've got a serious mess going on here. So far the neighbors haven't complained.
![IMG_0767[1].JPG](https://forum.ih8mud.com/attachments/img_0767-1-jpg.1514307/ "IMG_0767[1].JPG")
The wiring for the OM617 looks like it will be a cakewalk. I'll draw up a diagram after its done (and working) as I think I've pared it down to the bare minimum. I'm really stoked at the simplicity- it will be nice not having to worry about complex computerized crap.
First, had to take a step backwards and remove the radiator and rearrange things. By moving the radiator to the passenger side as far as possible (before hitting the headlight) I was able to mount the oil cooler next to the radiator on the drivers side. Fits perfect, almost like it was meant to be...the radiator is an unmodified FJ40 aluminum replacement. The stock Mercedes hoses attach pretty well, but it looks like ill need to shorten the top one a tad to get that bend out....
Back to work tomorrow, BUT, hoping to fire it up for the first time Saturday. Ill refrain from posting emojis until it starts.
And just to make sure the hood still closes with the alterations. Its very tight, but seems to be OK. Yes, I know, I've got a serious mess going on here. So far the neighbors haven't complained.
- Thread starter
- #56
Thanks-I have a question on that you may be able to answer: So just one wire to the 3 watt bulb and then ground the bulb?
- Thread starter
- #57
I was hoping today would be the day the motor would start. That didn't happen. Not for lack of trying, though.
Right now I suspect that there is air in the lines. The glow plugs/wiring seem to be working well, they take about 6 -8 seconds to glow. I have fuel to the rear three injectors, but don't seem to be getting anything to the front two. Still, no startee.
![IMG_0779[1].JPG](https://forum.ih8mud.com/attachments/img_0779-1-jpg.1514993/ "IMG_0779[1].JPG")
Right now I suspect that there is air in the lines. The glow plugs/wiring seem to be working well, they take about 6 -8 seconds to glow. I have fuel to the rear three injectors, but don't seem to be getting anything to the front two. Still, no startee.
I assume that you have used the primer pump on the side of the IP to fill the fuel filter and lines up to the IP, and then cracked the injector lines at the injectors while cranking to prime them?
My OM617 almost doesn't need priming to start; I ran out of fuel once, and it restarted with just a little cranking after I added some fuel to the tank.
My OM617 almost doesn't need priming to start; I ran out of fuel once, and it restarted with just a little cranking after I added some fuel to the tank.
Can't wait for this one to come alive! Keep after it. You're almost there!
- Thread starter
- #60
Sounds like your OM617 has great compression.
I pumped and pumped the primer. it is getting a little fuel to the rear cylinders, but nothing to the front two, just a drip at the middle injector. BTW, Does your OM617 have the clear fuel line that returns fuel from the injector pump to the filter assembly? I have air bubbles in that that I cannot get out.
I pumped and pumped the primer. it is getting a little fuel to the rear cylinders, but nothing to the front two, just a drip at the middle injector. BTW, Does your OM617 have the clear fuel line that returns fuel from the injector pump to the filter assembly? I have air bubbles in that that I cannot get out.
