Finally complete!

After 2 years of research and collecting parts I have built my own version of the Disco I 300D using the Mercedes Benz OM617 married to an R380 Manual 5 Speed trans. And I have done all this for less than 2000 dollars. Surprisingly there are not a lot of “SPECIAL” parts needed or “MAJOR” modifications required even by less skilled or resourceful.
This video is my motor running on straight clean Burger King fry oil right out of the jug. Not preheated.
Acknowledging credit to those who were inspirational, helpful and supportive will be mentioned in appropriate stages of the thread posting.

Editing periodically for reasons of omissions, relative photos or incorrect / out of context verbiage. I am trying to make the most of the photos I have and will be using Photobucket to serve my images as I can't figure out how to create in-line full size photos in my posts. So Full sized photos as they were taken are available there in my project albums relative to each stage of my build

The target audience for this project is Discovery I owners with R380/LT77 5sp or buyers that want Diesel Disco and don't have 2500-5k for the 300TDI Rover engine that in my honest opinion is not as reliable, durable and requires a heck of a lot to maintain! DII owners can do this too to a greater cost being the r380 transmission and some other stuff.

I stuck with pre 1999 for the original ROVER design suspension and axle composition. No offense to BMW fans but BMW downgraded alot of things in the post train especially in the front end that I feel was totally unacceptable. Say what you will but I don't feel going to a booted bearing CV joint thus eliminating the sealed, fluid and serviceable swivel cup axle assembly was a benefit other than shops saving time and making more money off cheap parts to maximize service profits. BOO and SHAME on BMW!!! Axle thickness reduction by a 3rd? come on!

The skill level u have now and what skill level you gain after the end of the project. This also depends on the resources you have to support the project including, willingness to learn, friends with viable skills and if done right about 800.00. Call BULL**** all you want but I did it with the addition of costs that could have been avoided.

I will be posting threads by sections:
300D Turbo Disco I Complete Build (Intro)
300D Turbo Disco I Complete Build (Motor) Live Now (Pics to come)
300D Turbo Disco I Complete Build (Adapter Prep) Live now.
300D Turbo Disco I Complete Build (Trans Mate) Live now.
300D Turbo Disco I Complete Build (Mounts)

ALL Questions should be relative to that thread post ONLY
Please keep commentary relative to the project and suggest only helpful alternatives.

My Benz motor ended up to be from 78 300CD. This is actually an OM617.950 with updated cam that gave the 125hp. 617.952 has significant changes for consideration that will be addressed in the ADAPTER PREP section The Benz motor build is for another forum and any questions about that should be asked elsewhere and after you have done your own research. Donor 700.00

My R380/LT230 xfer donor was a 95 DI I picked up as a daily driver for about 1600 2 years ago and I am not counting the vehicle purchase price for this project. Parts needed from this truck include Pedal plate assembly, clutch master cyl, lines and slave cyl a few other items which will be detailed in my Trans Mate part of my post

My recipient vehicle for the finished project is a 98 DI I traded outright for a Benz I was trying to sell.

Major tools I required were:

Heavy Engine Hoist with canter rig. benz motor is about 600+ lbs.
Heavy Engine Stand. 150.00 paid for both hoist and stand off CL
Welder. 60.00 paid for Lincoln 225 Stick off CL
12mm 3xSquare head bolt removal socket 5.99 ebay
4-10mm long hex socket set 7.99 on sale at harbor freight
1/2” chuck t handle drill. Neighbor loaner
3 ¼ and 4 ½ hole saws for crank bore and starter bore 41.00
Cutting Discs and wire brushes 25.00

Materials:

17" dia Mill CUT circular x 3/8 steel for adapter plate 125.00 (you may use 16.25 if u are machine capable but may be tight)
.20" 2@ 8" square tube steel and plate for mounts for free
welding rods 25.00
5 gal Xylene for parts cleaning (not for ruber EVER) FREE!!!!
Green spray paint 2@5.99 13.00
Cutting oil for drilling

Parts / Cost:

MB 240D Manual flywheel / friction plate / clutch disc(did not use disc) complete set from x benz mechanic 50.00
8.5x1x23spl clutch disk 19.00 ebay
turned crank 90.00
Bearings main and rod +.25mm 84.00
om617 low end seal / gasket kit with oil filter 22.00
om617 Reinz head gasket complete kit ebay 60.00
Holger Christinsen Glow Plugs 24.00
Bosch AL80X BENZ 100% new old stock alternator from ebay 63.00
STP air filter local 12.00
STC1126 ROVER clutch master cyl rubber kit from Rovah Farm 8.00
STC2818 Rover clutch slave cylinder rubber kit from Rovah Farm 6.00
shyte rip off motor I salvaged connecting rods, fuel injectors, fuel pump and updated cam with towers 200.00
Primary fuel filter 4.99
Roll Cage bearing for pilot bearing I used from local Mower shop 8.99

Fluids misc:

2 gal 80w90 for diffs at rural king 23.00
2gal oil 15w40 lubrigard 22.00
lucas assembly lube 4.99
2 gal straight coolant 28.00
1 gal diesel fuel for parts cleaning 3.729
1 Gal reg ATF for R380 fill and power steering pump at walmart 12.00
Lucas Red and Tacky 8.99

I think that is it for item / cost association. If there is something I may have missed, I will edit to append as needed.

The OM617 Motor.... It is a 3.0 5cyl. 1984 and before W123 Body 300D/SD/CD or the 300TD wagon
If 1985+ 300D w126 body, be sure it is a 5 and not a 6 cyl OM603. Some were fitted with 5 cyl OM617

Obviously you want to look for a well maintained ENGINE. Good sign is condition of the vacuum rubber components... Free of major cracking or fuel soaked and swelled y connectors and rubber tubes. Use good judgment. If motor does not shut off with the key it is a MINOR vacuum related obsticle and not a consideration of whether or not to buy. The fix can be free and 5 minutes or 14.00 and about 40 minutes of labor

Make sure Fuel Delivery System is in good condition. If the ALDA screw atop the IP is exposed make sure the person that modified the motor knew what they were doing as blown head gaskets and other serious issues are afoot if over boosting is in play.

Be ware and exercise caution if the issue of overheating is present. First concern is that head gaset failure exposes the cast steel head and block surfaces to water. The pitting caused by rust can be spread as far as up into the valves and seats and destroy piston rings and cylinder walls.



See this album for the rest. Check out the lip at the top of the cylinders... terrible deal.. And the pile of soot in the one is from a injector I found to have 2 shims and never closed all the way. This motor came from Joe at Sparrow British Auto on RT41. A 95/hr mechanic. Hmmmm.
If you have a flexi fiber scope, the damage can be inspected through each of the glow plug ports. If no damage, then suspect the stupid banjo bolted line located front of motor on water inlet housing then to the block. Or obvious water pump or hoses.

Disco Engine Removal:

This can take 1.5 to 3 hours depending on your tools and skill level. Drain and collect all fluids eg; oil, coolant and steering fluid and trans fluid and disconnect trans cooler pipe connections. Latex gloves and small zip ties make great containment of fluid as removal of oil cooler pipes and trans lines will spill fluid. As you undo each item, have a glove and a zip tie ready to cover the end of the pipe and the fittings on the trans and on radiator.

Remove serpantine belt and Viscous Fan
Re move radiator.
Remove Plenum box and throttle body and coolant hoses
Remove 18mm Nuts from motor mounts Top and bottom while motor weight is still applied as the nuts are oblong at the top so threads get tight and lock.
Remove Exhaust under manifolds

Remove Plenum box cover to reveal harnessing and Undo all harnessing but lable thermo sensor wire wht/blk, ignition wire brown and oil pressure sensor wire wht/gray (?) and lay harness to passenger side after O2 sensors unplugged. Trans and xfer case harness disconnects via square plug mounted on inner fender wall corner of firewall next to break booster.
Oil Pressure lead is White with Brown trace so I may have cut one of 5 wires I need. less two if I don't plan on having AC

Removal of Plenum box also allows you to see 14mm bolt locations holding trans and motor together and gain access to 10mm bots holding coil pack if you have 96 and above. Also easy access to 10mm nuts holding fuel rail.

Only accessory really need to come off motor is AC compressor if you want to keep system sealed for future. The power steering pump is optional unless you prefer to keep that sealed up till later as well

Save lower 4 way radiator hose and top hose and coolant res.

Everything else in the engine compartment can be stripped with exception of main fuse box and lighting harness and break system.

Removal of the air cleaner box makes room for a second battery... and mounting of glow plug relay yay!.

The order of which you do everything else is up to you.

Disconnect AC Compressor mount from engine and roll it aside and tie down by coolant res if you plan on keeping AC system sealed and out of the way.

Disconnect power steering pump from engine with series of 10mm bolts.

Using an assortment of extensions and swivels, and a 14mm socket, Unbolt trans from motor, remove trans inspection plate and using jack supporting trans weight, divorce the trans and motor with your hoist and sell that piece of ****! I got 600 for my 4.0 out of my 98. So there is money to be made in this project if you work it

Hoist / lift tongues are on heads between head and power steering pump bracket and passenger rear head caddy corner each other.

If you have an auto box ready to come out, inspection plate removal reveals flywheel to toque converter bolts, 13mm/1/2in Remove them and you don't have to fight the weight or added length of the torque converter attached to your rover motor

Photos to come in each project section. I have lots!

 

Subscribing!!!!

 

Subscribing as well!!!

 

So, your work proves that it can be done. But, even more valuable to me would be your opinion whether it should be done. In other words, is the OM617 a good fit for the demands of such a heavy vehicle? Now that you are finished, how does the truck drive "in the real world"?
I imagine that if I did this to my Discovery, I would have a daily sense of pride at my accomplishment, and the pleasure of getting better fuel economy.... but I am afraid that I would also experience a daily exasperation at the lack of power. Can the OM617 pull the truck at highway speeds? Does she behave nicely in city driving?

 

I am satisfied with the performance. The only thing I had to get used to is soft pedal and where to rev to engage the clutch as top end is non existent compared to git up and go to ANY gasser. It is by far nod a street performer and you cannot peel wheels at a stop light, but I can go about 75-80 on highway at about 3400rpm. It is a high RPM motor and power is going to be achieved above 2000RPM but it cruizes nicely.

I am not an aggressive driver and I am not heavy on my pedal. But when I tell the om617 to move, it does

Fuel economy is night and day. I can drive to Tampa from my town and back on about 13.00 vs 20.00 given the 20-30 cents price difference between diesel and gas, I can honestly say I have close to 2/3 increase travel distance. I was getting 12-16mpg GAS. I am definitely above 23. I have less than 300 miles on it and there are some tweeks I need to make to get my target 25+MGP.

Whether or not you should do it, that depends on if u can weld enough to melt metal togethr for your mount fabrication method or if you know a welder. Also if you don't wish to modify the lower oil pan, you should have 3" lift HEAVY DUTY springs installed.

The weight is not an issue for my purposes and the R830 trans in my honest opinion is a GREAT match to the motor torque. Even an LT77 may do if you can find one.

Diesel TOTALLY changes the truck and I like it. Ultimately with a properly running om617 motor, I would do it again. Although a om606 is my next prospect but the length and the insane amount of maintenance required may not justify.

 

Can you provide insight into your plans for registering the diesel powered Rover with your state motor vehicle department? Some people say that federal law prohibits puting an older engine into a newer vehicle.... Some people say that local authorities can do as they please. Some people say they just don't care... don't ask, don't tell.

Here in Texas we have anual emission testing, which requires the use of the OBD plug... but diesels are exempt from testing... So, I'm thinking I would need to get the title changed to "diesel", so that I can avoid the testing altogether... but that would require navigating the delicate older-engine-in-a-newer-vehicle issue. Catch 22.

Are you going to re-title the Rover as a "diesel", or just drive it as is, or what?

 

Kent, what area are you in? I am in East Texas and we don't have emission testing (except visual, to verify the presence of something that looks like a catalytic converter... if they even look).

 

I've done a swap 4D55 Diesel into a Ford Ranger. Seattle. This Discovery - to - OM617 will be my second, and worrying about licensing and titling is a non issue. You do want to look at your states laws. In WA, if your diesel and your under a scale limit, your emissions are waived. To change your registration from GAS to DIESEL, you just say it has a diesel engine. I've called several DMV's when I was worried about the issue the first go around, and they all said the same thing - your ok.

The whole "older engine in a newer car.. yadda yadda" is apparently federal, although states have the right to make their own emission laws in these regards. IF your state is picky there are always ways around it as well.. get it licenced as a "kit" car... etc.

 

I used to live in Waco which doesn't have emission testing... but moved up to the DFW metroplex. I know diesel is exempt, but the inspector will just enter the VIN in his computer which will tell him it needs OBD connection. I doubt they would pass it unless it has "diesel" on the title.