1992 745 turbo diesel swap
 

Well I'm starting a new swap project, I have done several gas to diesel swaps on the 240 series (so easy!) this is actually my first 740 gas to diesel swap..
Here is the rig. It's been in the family for a while, it got overheated and popped the head gasket or cracked the head. So.. The family member decided they didn't want to fix it, so I decided it could use an engine with good power and fuel efficiency. Ideally would like to start off with a turbo gasser as the washer bottle, air filter and battery are on the correct sides for the diesel swap.

It's on the hoist!
 

Time to get busy! Lots to do, trying to get it done in a few days.

Engine and transmission out! I dropped the engine out with the crossmember because I need to install the diesel crossmember. I had purchased a 1986 744 that I was going to restore as it was my favorite color combo ( black with black interior!) but I found it to be severely rusted when I put it on the lift. So it's being used as the donor for this wagon swap. Here is what has been removed from the 86 744:
Engine crossmember, battery tray, washer bottle, air filter box, transmission, transmission shifter, transmission crossmember, driveshaft, fuel tank filler neck and fuel tank sending unit.

Old vs new
 

Old b230/AW combo next to the D24T/ZF I will be using. The d24t and zf are not from the 86 donor as I opted for a engine and transmission with low miles. The D24T was a green car company import engine, what's really cool is the engine is a 1992 and so is this wagon! The ZF is from a 84 sedan that was totaled two decades ago.. Transmission has been waiting patiently in my barn for a worthy host.

Yep, the D24T will be using the NA intake, I will also be running a Holset HX30W turbo (44mm,6cm w/MWE) I found that this turbo is an awesome performer in a moderately modified D24T. I do have plans on using a 12mm pump head, 3" exhaust, intercooling, ect.. I have allready installed ARP head studs along with a rebuilt cylinder head.

Is that crossmember one of the later reinforced ones?

I believe so, I think all of them are after 1986?

Engine and transmission are bolted in! Along with the driveshaft and radiator. Also a pleasant surprise to find the b230 AC compressor bolt right onto the D24T pump bracket and no modifications needed for the hoses.

Started the engine wiring. Here is what the engine harness looks like before removing the unnecessary wires.

Here is what the harness looks like after removing all the not needed wiring. On the left is the wiring that will not be used, on the right is what will be used. I still need to add an ignition wire, Coolant temp signal for glow plug relay, and tach signal from the alternator.

Started moving battery and washer bottle location. What I found out is I can't use the factory air box from the 1986 744 because of the ABS pump is in the way.. I'm not sure what I will do now, I have several ideas. One of them is to use the battery location alone and use a type 78 battery or similar on the passenger side and then use a universal air filter above the battery and leave the washer bottle in its current location. The second idea is to build a battery tray to go above the washer bottle on the drivers side, the plus to this is I can install a water to air intercooler on passenger side below the airfilter.

Im now 26hrs into this project total, 8hrs was stripping the 1986 744 and installing a rebuilt head and head studs onto the donor engine. Three days into working on this wagon, been working short days (6hrs/day) as I have other obligations.
I would say it's going together fairly well. The Turbo, alternator and power steering pump have been installed along with a mechanical cooling fan (the electric fan was hitting the hub for pulley that the mechanical fan bolts too) I may install the electric fan at a later date so I left the wiring for it intact. I plumbed the cooling system and heater hoses, installed the needed brackets on the injection pump for the ZF transmission lockdown cable and also installed the correct cruise control spool. I'm hoping to have this car fully operationable just like it would be if it came factory with the D24T.

I don't remember the date ranges but you will know it upon visual inspection. Think hat cross section, the verticals are boxed in (plates welded in over the open places on the channel where the horizontal changes to vertical), obvious reinforcements.

(LATER) This is the thread:
https://www.d24t.com/showthread.php?t=978

"For diesel owners looking for replacement crossmembers, 1989-1991 740 and 940 GLE models having the 16-valve B234F gasoline 4-cylinder are the only other models that use a welded-on lower mount bracket on the left side like the diesel models have, and they were manufactured after the change to the updated crossmember design, IOW, they use the same desirable crossmember that the diesels only got for their final model year in 1986."

Looking great, I really like the D24T swaps into later 7/9 series cars. The later interiors seem to hold up better, you get nice things like ABS and more features, and of course the body wiring doesn't fall apart like it does on the early cars....

Looks like you had a Rex/Regina injected gasser to start with. Interested to hear what you end up needing to do with the fuel system. I think most of those Regina cars had just one high pressure main pump in the tank unlike the Bosch LH cars with the low pressure lift pump in the tank and the high pressure pump inline under the floor. The low pressure LH pump worked great for me as a diesel lift pump, I just bypassed and removed the high pressure pump. I think if you use the old diesel car's tank pickup/sending unit it might not play well with the later style dash gas gauge, seems like they changed something with the sender setup in the later cars. I wonder if you would be able to get the low pressure pump and sending unit out of a similar year Bosch car and swap that right in. It might work with the '92 fuel gauge and having that low pressure lift pump is actually pretty nice, makes changing fuel filters a really quick job and I guess some people think it helps add a little more power. A lot of the TDI guys like to add lift pumps in their VE pump cars, who knows if it's really helping them or not though.

I didn't know the greencar co brought in any TD engines, seems like everything I ever saw them do was NA D24 conversions on gas 240s and a lot of those were pretty hacked together (and they sold them for $17k....). I remember they did quite a few of them back in the day. Maybe they finally figured out turbos were the way to go at some point? Was that motor one they had loose or out of one of their built cars?

Sounds like it'll be great when done, like to see it some day. Will be interesting to hear how the ZF holds up to the extra power but I bet it will be fine, any plans for work on the trans? I've never seen any shift kits for them but seems like they are pretty tough and don't really die from abuse, mainly just from the known A-clutch issue that they have a fix for now.

I remember back when Jason had his motor cranked up quite a bit and was doing fine with the ZF, then swapped in an M46 and broke it within a couple days, then broke another one shortly after that. Guess the ZF wins that contest! :eek:

Fuel gauge
 

You are doing a very nice swap! Share it all


I dont mean to clutter your nice swap thread but i have this 740 volvo gas-diesel question here...
My car was swapped too, it is a 1986 wagon body that was born to be an auto gasser turbo originally but then received a 1985 d24t unit mated with the standard shifter tranny. It BTW has been an amazingly reliable build ... many thanks, huge credits and respect to v8volvo the professional d24t bricker.and perhaps Ngoma.

I have a question relating to the fuel gauge because my gauge reads incorrectly. It marks empty when fully filled. It climbs to the right (towards Full) as the tank starts getting empty. It also does that pretty inconsistently (showing pretty late or last minute) but it climbs towards full and as/when the tank gets empty it reaches the Full mark. When i fill the tank it moves towards the very left to mark "empty". Always been doing this ever since, not a new issue.
IDK why it works this way. What can it be and is there a suggested fix?
Facts that i know:
I never removed the in-tank parts and i did not mix up the wires behind the instrument cluster.

Left side is red zone = empty, right side is Full.
But the gauge works the oppositecway and really incorrect in terms of how slowly it picks up to warn about an "empty" tank. ...that is the factory Full marking on the gauge that itself is located on the left side of the cluster and ***the right side within the fuel gauge***

Thanks for any ideas.
About the crossmember....yes mine is 85 and has cracks both sides ...that i drilled at the ends of the cracks to stop a possible spreading of the crack(s).

I should either get it welded, boxed or replaced one day.
I agree with v8 that it was a good idea for you to use a later than 86 donor with a more modern body.

Your fresh swap-sights of both gas and diesel fuel systems might reveal the secret... Maybe it takes minutes to fix. But i do know that a working fuel gauge in these bricks is already a half miracle...so ..i should have no complaints and be happy that it "works"

Yep the resistance in the sender is just the opposite on the 92 vs 86. The 86 sender was 36ohm empty 288 ohm full. The 92 was 277 empty and 2 full. I’m glad I checked! I had to eliminate the high pressure in tank pump, it wasn’t being kind about letting fuel being pulled out. So I used some 5/16” steel pipe and made a suction pipe.

When they finally realized they couldn’t build cars they sold off all there parts, at least that’s what I assume. I say the craigslist add years ago with all there late d24 engines for sale. But this engine actually came from one of there hacked up cars.

The ZF does seem to hold up well, your old silver 764 currently has a built engine with a 12mm pump, hx30, ported head, 2.5” straight pipe, and large intercooler. The transmission seems to be holding up well and shifts nice and crisp under full throttle. I do plan on building one of these ZF transmissions though.

It’s alive!
 

Well it now runs and drives, with some roadblocks on the way of course! 1st startup revealed no throttle control :-( So I was thinking to myself no problem, been there many times before, open up the pump while still mounted on the car and fix the governor and collar. Not so fast, pulled the top cover off and this is what I found.. one little tong broken from the throttle spring cage, not good! Did it happen previously, did I do that? Is there a metal chunk now floating in the pump?!? Ugh!

So pump is removed from the car and stripped down, looking for the needle in the haystack. Found it! It also found the governor gear :-( so from the looks of it I didn’t do it, I didn’t break the cage.

Surprised it would even start/idle.

Good question: Why would that tab break off?

I had a similar, where the "lobster claw" that encages the long spring broke. I figured it was due to my previously replacing the IP top cover gasket and not quite getting the mechanism positioned correctly when replacing the top cover. That is a tricky one. The Dodge/Cummins version of the Bosch VE IP has a much simplified throttle arm mechanism.

I think it broke because of the mechanical shutoff lever, it’s difficult to get the top cover off because of that lever, the throttle cage likes to get stuck on it, that’s the only thing I can think of.


Well since I had the nasty pump apart to find the missing piece I went ahead and gave it a good cleaning, re-sealed it all and installed a 12mm head/rotor on it. Even though I don’t plan to make lots of power with it, I like the 12mm head and rotor because I can get more fueling control with the LDA. That means more power with little or no pre-boost smoke.

That appears to be a common theme. Maybe the best way to reinstall the top cover is to first remove the throttle arm shaft and cage mechanism from it, install that in the IP, then place the top cover, working the throttle arm shaft thru its seal and opening in the top cover.

After pre-marking the position of the throttle lever to the shaft, of course.

Might require a new throttle arm shaft seal there each time.

What do you think?

When it broke on mine it left me stranded on the side of a busy freeway in a heavy rain.

You just have to be very careful pulling and installing the top cover, I always leave the governor spring assembly and throttle shaft with the main body of the pump, but since the manual shutoff lever is on the top cover you have to weasel it past the spring cage, I found you need to manipulate the manual shutoff lever while removing and installing the top cover. I tell you it’s sooo much easier to do on a Cummins VE pump since they have the other style spring.

I started wiring the glow plugs (thanks George!) and the tach, it all works! Now I just need to tidy it up. I’m in the process of building an aluminum battery tray also.

Tell me about the battery tray. I need to do something for my (50% gone) battery tray.

I would replace yours with a factory composite one. I have to build mine because I will not be moving the washer bottle. I finally got around to building one, it’s not yet installed though.

It now has exhaust! All 7.3 power stroke exhaust parts! Performance OBS downpipe modified for the Volvo, from the downpipe back is all used 3.5” from a 2002 E450.

Picture of entire exhaust.

Looks like that OBS downpipe fit nicely. What did you have to do to it to get it to line up that well?

I cut about 10” from the turbo side and welded a 2.5” v band on it, rotated the two 45* pipes to the configuration that fit and installed a 3” v band to the end, I didn’t expect it to fit as well as it does!