Mercedes-Benz Forum banner

My Camper Project

403K views 1K replies 105 participants last post by  TRUKTOR 
#1 · (Edited)
Australian Unimog Camper Project

This is the start of my camper project thread. I will post the photos as I progress the works, hopefully in the end it will match some of the other threads I've seen on build-ups here.


First off - this is the photo from the auction the persuaded me to buy this Mog




Then the night I got it home.




This weekend I sold the crane and cherry picker - I drove it over to the new owners yard, and in the course of a few hours, we had the whole sub-frame off. On the way to his place it struggled up the hills and could hardly reach 60kph. On the way back, it was keeping up with the traffic even though I could not get it to rev past 2100rpm. I'm sure it's got something to do with the fuel pump settings or the fuel filters are blocked. It had a good turn of acceleration, even with most of the high-rail system still attached.

This is how it is today, I'm starting to remove the hi-rail system and will strip out all the masses of associated pipe work.








More photos to come as things progress.
 

Attachments

See less See more
7
#658 ·
What you have is a "tractor governor" and a "truck governor", research the differences, but I think the truck governor is alot better to drive with.
 
#659 ·
I've had both on SBU's, I actually, personally, prefered the tractor style on my U1700AG for highway driving, you'd just set your speed, and it adjusted for hills by itself without having to push the pedal to the floor, sort of load balanced, needs more power to maintain RPM, it seemed to give it more fuel to hold the set RPM's.
 
#661 ·
Interesting, The tractor governor definitely feels different from the others that I've used (truck gov's), My RW1 used to compensate, but certainly not like the Tractor gov. I think the tractor gov is designed to hold the rpm while disking, plowing, whatever for heavy pulling farm style. (I think...)
 
#662 · (Edited)
I did a lot of research on what the differences between the governors, but these RQV-300 seems a lot different to what I have seen on other Unimogs, and I am not sure exactly what the one on the U1250 is, I always assumed it was also an RQV as well, given the truck had a crane and cherry picker running off a large hydraulic pump.

The diesel shop recommended the RQV ( tractor) governor as the better on to drive with in their experience as well. He also said it was a more "tuneable" governor. The RSV with the boost compensator would produce less smoke, as it can reduce the fuel load when there is no boost making for a cleaner burn. He says he has an RQV governor with a boost compensator in his workshop as well, which they thought was the best of all the types, especially given my turbo will spool up a lot quicker and provide a lot more boost from just above idle.

He was going to get all the "test plans" for the two different pumps and see how he could adjust the fuel maps for either pump/governor to give me a bit more power, but what is more important is to get the map right to give optimum fuel economy, To me, there no point making lots of power with your foot flat, but pouring in too much fuel under coasting condition or light throttle, washing the oil off the bores and creating all sorts of problems in the future.

I have played around with petrol engines since I was 15, and have destroyed a couple due to my not understanding the whole relationship between all the factors. i was getting pretty good at it before I swapped over to diesels. However I learnt that it takes a lot more time and knowledge to really get it right. I fitted a fully programmable fuel injection system to a friends V12 Jaguar XJ-S, it took about 10 minutes to get it to start and idle properly, about 20 minutes to get maximum power settings tuned up on the dyno, and a basic fuel map, then about 20 hours of on road testing to make it driveable, getting rid of the light detonation (pinging) at light throttle up slight hills, and slightly decent economy. Despite all the variables I could change and many weekends and dyno runs, constant adjusting and tweaking, I could never get it as good as the ancient old 1980's design AJ6 Engineering ECU and mechanical distributor on my XJ-S tuned by Roger Bywater, who was the engineer who did the OEM ECU tuning and mapping for Jaguar during the development of the engine.

I think there is a lot more to getting a better fuel system than just bolting on a bigger fuel pump and then trying to adjust the limited setting with a spanner hoping not to melt a piston in the meantime. I looked at a lot of different injectors from all the various OM352/366 models before deciding just to go with the standard U1700 ones. The pump, (and the plungers, springs, weights etc inside the pump) , injectors, camshaft, piston bowl, turbo etc, all need to be matched up give reliable and powerful upgrade. I don't understand all these variables and there does not seem to be the information out there, at least not where I can find it. Even finding proper info on the RQV vs RSV types of governors is impossible other than the very basics, and even then some of the "experts" on various diesel forums that have stated as facts the exact opposite to what is in the technical literature.

The more I learn, the more I think getting it done at a proper diesel specialist with all the proper test equipment and fuel map data is the way to go.
 
#663 · (Edited)
#664 ·
fuel maps are not really the same between gas and diesel. The map on a diesel is not easily changed and requires major hard parts to be changed. There are very few diesel shops that will modify your "map" as it just does not work quite the same as gasoline.
 
#665 ·
Both my old block and my fancy new one came with some material removed right there to clear the gov'ner.

C.

Auto part Metal Automotive tire Engine Steel


Metal Auto part Steel
 
#666 ·
Mine has a little bit of metal removed, but no where near enough to clear on that massive RQV governor. Maybe there is a different size RQV governor fitted to the other Unimogs. I will use the new pump, and get the RSV governor fitted to it. I see you have an inspection port of some sort in the top of the block, my old one had one as well, but the new one doesn't.

I've sent the two pumps off to "Diesel Solutions" in Maryborough to get the work done, Ursus had his injector and pump set up by them and they seem to do a good job.
 
#667 · (Edited)
Found this book, very useful on all the different types of Bosch pumps and governors. Some of it makes sense :) There is certainly a lot more to fuelling than just winding up pump few clicks.

Text Yellow Paper


I am putting all my old gears back into my portal boxes for the high speed axles, using all the new bearings I bought a few years ago and some new seals. I noticed that the bearings on the boxes that came with the axles are different to the ones I have.

These are what I bought for the OEM lower inner portal bearing, a deep groove ball bearing, these match the ones I took out and the workshop manual.

Auto part Automotive wheel system Bearing Rim Wheel


I am cleaning and checking the ones fitted to the high speed axles as spares. They have different bearings on the lower inner portal bearing, a roller bearing.

Auto part Wheel Clutch Rotor Automotive wheel system


On the upper portal gear, the new OEM bearings are a roller bearing, whilst the old ones are a ball bearing, which were on my portals originally ( and pretty sad shape) and match what is in the workshop manual.

Auto part Clutch part Circle Wheel


Seems like the engineers MB decided to change some of the bearing specifications along the way.
 
#668 ·
Engine building

Just thought I would post a few screen shots from the engine re-build. I recorded the whole process on GoPro cameras. When I get time I will try and put a bit of video together of the whole process.


Installing the last valve on the cylinder head.

Auto mechanic Metalworking Mechanic Artisan Metalworking hand tool


Completed cylinder head

Engine Machine Auto part Vehicle


Plate type oil cooler insides

Auto part Radiator Metal


Plate oil cooler ready to be attached

Auto part Engine Automotive engine part


Installing the crank - that thing is damn heavy

Auto part Mechanic Auto mechanic


Torquing down the main bearing caps, three stage torquing required.

Metalworking Auto part Engine Automotive engine part Tool accessory


Camshaft installed

Auto part Machine Automotive engine part Engine Machine tool


Timing gear installed - there are marks on both the camshaft timing gear and the crankshaft gear, makes it very easy to get it right.

Auto part Machine Engine Automotive engine part Machine tool


Block ready to install the pistons

Auto part Engine Automotive engine part Vehicle


Crank with all big ends assembled


Engine Auto part Automotive engine part
 
#674 · (Edited)
I will put the whole series of videos together, so far I have the engine re-build, replacing the seal on the transmission, and re-fitting the rear axles, rebuilding the portal boxes and installing them on the axles, fitting brakes callipers, brakes discs, hub etc. I will edit out some of the mistakes, but leave in the not so obvious ones so everyone can see what not to do as well. :) I'll have to speed it up a bit, skipping out all the parts where I am looking for tools, bolts, nuts, reading the manual, looking at the dismantling photos etc. Looking at the footage, I seem to spend a lot of time doing all those things.

Yesterday was a pretty frustrating day, putting the rear axle together. The new axles are off course slightly different from the old one, so things that should just be a "bolt on" end up having to have some minor "adjustments". The springs needed to be rotated to fit on the plates properly. The left one was fitted properly previously, but the right one needed to be rotated 60 degrees. Now that sounds easy, but the top bolts are torqued up to 300Nm or so, and trying to get the socket with the power bar was pretty difficult, and required a large pipe on the end to get the bolt to move. The rear sway bar connections are also slightly different from the old axles, about 5mm narrower, but the connection rods to the sway bar are different to mine. So I had to remove 5mm off the new bushes in order to get them to fit.

Next was replacing the 25 year old panhard rod bushes as an absolute pain to remove. I could not get them to budge with a 10ton hydraulic press, so had to do it the old fashioned way. I stripped the M12 high tensile threaded rod, and even stripped three M12x200mm capscrews when I was pulling the the bushes out using sockets. I had the 3/4" drive ratchet on one side, and the super long 1/2 drive power bar, and was getting a quarter turn at a time, pulling with both hand whilst sitting on the power bar and the panhard rod. After I had got the old ones out, I had to repeat the whole process pulling the new ones in. When I get both ends of the rod done, I go to fit it, and discover I have done the front one, not the rear one. So I had to repeat the whole process on the rear one before I could fit it :(

I don't know how many of you have every fitted the panhard rods, but there are an absolute pain to fit. The only way to line up the bolt holes is to jack the axle up to the right angle, or there is not hope of getting it even close. Then you have to make sure it is in the right position laterally, it would be good if I had two jack trolley jacks with enough height to also me to lever is laterally, but I only have one big jack, and had to use Unimog 10ton jack for the other side, so it was a case of jack it up, estimate how much I needed to move the bottle jack, jack it up again, and then after and hour of jacking, levering, pulling and wiggling, I managed to get the bolt in.

Finally, I get everything fitted on the axle, and move on to fitting the portal box. It went in with out a problem, with only a few bolts having to be changed over to cap screws in order to get them to be torqued up. I have no idea the factory was able to get a torque wrench on the top four cap screws on the portal box, as there is just enough clearance for the large allen key and a pipe extension to get them up to 90Nm, which was more of an estimate than a proper torque based on the amount of effort needed to pull the torque wrench on the other bolt I could the the torque wrench on. Finally, all I had to do was fit the rear brakes, I fit the callipers, torquing the bolts up over 300Nm, for which I needed the 4' torque wrench. I get everything installed, and torqued up, then find that the spacers that were fitted to centralise the old brake discs, are not required on the new discs. This meant I had to pull it all off again and redo it all again. I was 8:00pm before I got the left rear corner all installed, I went home leaving the right hand corner for tomorrow, because today I went to the beach :).

The torque on the bolts on the Unimog are really high, the rear shock bolts are torqued to over 400Nm, and the hub bolts are also over 300Nm - and there are 10 of them. Lucky for me it is not the U1700 with the big heavy duty axles, reading the torque requirements off the manual, there are loads of bolts over 600Nm, that is some serious effort required to tighten those bolts. I feel sorry for you guys with the big Mogs, you will need some serious muscle power if you are working on those axles.
 
#678 ·
Good point guys, I have a 4' torque wrench, but it is not so easy trying to get it to fit under the truck, not impossible, but just not easy. :)

Gary, maybe I should get one. The price brackets seem quite different. Ebay are around $50 to $150.

Torque Multiplier Truck Wheel NUT Remover | eBay

Torque Multiplier Truck LUG NUT Remover With 15 Sockets AND 1 Adapter | eBay


Then there are the ones starting at $650 going up to $16,500.

Jimy Tools 5pc Torque Multiplier SET 2500nm 41 SA81 05 | eBay

Norbar HT3 Torque Multiplier 3 4" 1" 1300nm 17221 | eBay

Proto 577 6222CERT 2200 FT LB Torque Multiplier Certified | eBay
 
#681 · (Edited)
A few jobs done

Things are progressing OK now, the back axle is now installed, including the portals, brakes etc.

Auto part Tire Automotive wheel system Engine Automotive tire


Next job was to get the old engine out.

First off, remove the bullbar and all the extra bits from the engine bay to make room.

Automotive exterior Vehicle Bumper Car Auto part


Then to remove everything that can possible get in the way or get damaged.

Technology Vehicle Machine Engine Auto part


Then to tilt the cab.

Motor vehicle Vehicle Car Auto part Engine



Finally, to get the engine out.

Vehicle


Here is the new engine waiting impatiently for it's new home.

Engine Auto part Machine Vehicle Automotive engine part


I have a few job to do before putting the new engine in, like getting a new sump, fitting the flywheel, clutch etc, fitting the fuel pump, new injectors, and doing the first pass on the valve clearances. I'm expecting all going well to be ready to put the new engine in by next weekend.

I will also make some proper brackets to hold down the fuel lines, hot water system lines, and the various electrical cables that run down the chassis. I'l also fit the sound insulation on the underside of the cab. I have some ideas about some sound shields over the transmission the I'll have a bit of messing around with.
 
Top