MB 1120 Coming to America! Purchase, Build and Now Travel!
- Thread starter VerMonsterRV
- Start date
LostInTheWorld
Builder/Traveler
It's always so cool to see a habitat on for the first time.
VerMonsterRV
Gotta Be Nuts
Thanks guys for the encouragement, really neat to see the truck taking shape. Since this is my forst build this is a bit of an evolution.
I dropped off the truck yesterday at the welders (wanted to drive in daylight on a Sunday). Heading back first thing this morning to talk with him about what needs to be done. I noticed on the drive that it already rides a bit better and is quieter with the box on. My guess is as I keep adding weight the ride will continue to improve. All in all I think for a 30 year old truck it feels pretty good going down the highway, and in reality, does not feel like a 30 year old truck.
While at the welders he is also going to try and give me an idea on cost and if possible, for the A/C compressor install, which would take care of one issue.
One other thing is top speed, while building the habitat there was also a guy storing his RV in the same shed. He happened to be a retired heavy truck mechanic and advised me to not run the engine at high revs continuously. Got me thinking about top speed again. We have the 41:10 ring and pinion from the VIN lookup EPC, so I think the "high speed" version, though I am wondering if it has been changed since new as using an online ratio speed calculator has us falling a bit short (it calcs at 2500 rpm with our 42" diameter tires we should be doing 76mph, and we are doing about 64mph, am I missing something). Has anyone looked into a custom ring and pinion, and is this even possible at a somewhat reasonable cost? The engine seems to have enough power, even with the box on I was able to keep in 5th going up hills in Vermont back roads with very little drop in speed. I have never removed a differential cover, is it that difficult with this truck so I could verify the ring gear tooth count? Or is there an easier way? If I find I do not have the 4.1 ring/pinion is it a big deal to replace?
And since the cab has gotten a lot quieter with the interior upgrade other noises start to become annoying. Has anyone looked into a way to quiet down the cab heater/vent fan? Probably not likely but even on the low setting it is louder than I would prefer. I know in some collector cars owners have changed the fans out to a more modern fan to increase air flow and reduce noise.
And lastly (for now), cold weather starting. As you can see in the pic it is now winter here with some below freezing days. The truck in warm weather used to start right up, now it takes a bit of coaxing. One boat we had, had glow plugs to help start in cold weather. I do not see anything like this on the truck, is there some procedure for cold weather starting? I do plan on installing a Webasto hydronic furnace and will use this to preheat the engine, but for now is there anything else I am supposed to be doing?
I dropped off the truck yesterday at the welders (wanted to drive in daylight on a Sunday). Heading back first thing this morning to talk with him about what needs to be done. I noticed on the drive that it already rides a bit better and is quieter with the box on. My guess is as I keep adding weight the ride will continue to improve. All in all I think for a 30 year old truck it feels pretty good going down the highway, and in reality, does not feel like a 30 year old truck.
While at the welders he is also going to try and give me an idea on cost and if possible, for the A/C compressor install, which would take care of one issue.
One other thing is top speed, while building the habitat there was also a guy storing his RV in the same shed. He happened to be a retired heavy truck mechanic and advised me to not run the engine at high revs continuously. Got me thinking about top speed again. We have the 41:10 ring and pinion from the VIN lookup EPC, so I think the "high speed" version, though I am wondering if it has been changed since new as using an online ratio speed calculator has us falling a bit short (it calcs at 2500 rpm with our 42" diameter tires we should be doing 76mph, and we are doing about 64mph, am I missing something). Has anyone looked into a custom ring and pinion, and is this even possible at a somewhat reasonable cost? The engine seems to have enough power, even with the box on I was able to keep in 5th going up hills in Vermont back roads with very little drop in speed. I have never removed a differential cover, is it that difficult with this truck so I could verify the ring gear tooth count? Or is there an easier way? If I find I do not have the 4.1 ring/pinion is it a big deal to replace?
And since the cab has gotten a lot quieter with the interior upgrade other noises start to become annoying. Has anyone looked into a way to quiet down the cab heater/vent fan? Probably not likely but even on the low setting it is louder than I would prefer. I know in some collector cars owners have changed the fans out to a more modern fan to increase air flow and reduce noise.
And lastly (for now), cold weather starting. As you can see in the pic it is now winter here with some below freezing days. The truck in warm weather used to start right up, now it takes a bit of coaxing. One boat we had, had glow plugs to help start in cold weather. I do not see anything like this on the truck, is there some procedure for cold weather starting? I do plan on installing a Webasto hydronic furnace and will use this to preheat the engine, but for now is there anything else I am supposed to be doing?
LostInTheWorld
Builder/Traveler
On the topic of cold starting:
Our stock OM366A has an ether system to help with cold starting. I'm not sure if your truck has it, but you might want to take a look. On the engine, it looks like very small plastic tubes running to fittings on the intake manifold. There is a little round knob by our gear shift to inject the ether. Our old LMTV had a similar setup with no glow plugs but an ether system (the LMTV had a dash momentary switch to inject the ether). I'm not really a fan of using ether. I think it can be a little hard on the engine if used incorrectly, and I don't like messing with the little ether cans and stuff. That being side, if your truck has it, it might be a good temporary solution. I think in the long term, hydronic is the way to go for sure.
Michael
Our stock OM366A has an ether system to help with cold starting. I'm not sure if your truck has it, but you might want to take a look. On the engine, it looks like very small plastic tubes running to fittings on the intake manifold. There is a little round knob by our gear shift to inject the ether. Our old LMTV had a similar setup with no glow plugs but an ether system (the LMTV had a dash momentary switch to inject the ether). I'm not really a fan of using ether. I think it can be a little hard on the engine if used incorrectly, and I don't like messing with the little ether cans and stuff. That being side, if your truck has it, it might be a good temporary solution. I think in the long term, hydronic is the way to go for sure.
Michael
Ozrockrat
Expedition Leader
WARNING. Before you use starting fluid make sure you do not have a grid heater. (I will attach a photo of mine when I get out to the truck)
You could also use a propane based aerosol such as WD40 (if it is still propane). Not as efficient or rough on the engine as ether and a whole lot safer to have around.
Also just as a point of interest. The Australian icon marketing name for ether starting fluid is “Start Ya Bastard”
You could also use a propane based aerosol such as WD40 (if it is still propane). Not as efficient or rough on the engine as ether and a whole lot safer to have around.
Also just as a point of interest. The Australian icon marketing name for ether starting fluid is “Start Ya Bastard”
mog
Kodiak Buckaroo
Cold start - My 1017AF (OM 352A) has the ether system. Black knob on the dash. My understanding it is not some magical formula, but a can of ether at the auto parts store is $2.50, while the 'magical' Mercedes formula (the only can that fits to recharge the reservoir under the hood) is $50+. I've found that with fully charged batteries I do not need to use it, but 'mild' Southern Oregon weather here. Someone needs to make an adapter to fit a standard ether can to the recharging port on the truck. The trucks operator's manual is very clear on its use and limitations.
Top Speed - With highspeed axles and 395/85-20s my never exceed speed is a finite 68mph. It seems most happy at 62mph (all speeds listed are GPS confirmed). Even when trying to drive at 55mph for better fuel economy it natural creeps up to 62mph. But even downhill, tailwind max throttle, 68 is it. I am guessing the drag overcomes everything else.
Hills - Sometimes when a not so long hill is started at the perfect speed/rpm an almost 'normal' climb is possible (shocked face). But normally with any sort of long/steep grade (lots of those out west here), it will slow down to 40-28mph. Never slower than 28, as that is in 3rd gear. I've found this not too much of a hassle as I am still at the speed or slightly faster than the Class 8 trucks, so I just become one of the many trucks chugging up the hill, but not holding anyone up.
Noise - Triplecab so a lot more room for noise to dissipate, but for reference. First, this is the only vehicle I have that does not have any wind noise with a window open. Even with just one, no drumming, whistling, etc. Kind of freaky in a good way. Even my CLS can't be drive without noise with only one window open. A normal conversation can be held at cruise speeds, with the biggest problem is just the distance between the drive and passenger. That said, I use noise canceling headsets/plugs to listen to music as it is so much clearer. Of course, you have to check state by state if that is legal. Here in Oregon, both (canceling and music) are legal. Of course, common sense dictates to run the volume so you can still hear sounds from outside (horns, sirens, UFO tractor beams locking onto your truck, etc)
"not run the engine at high revs continuously"
Again pertaining to the OM352, my understanding is these were/are also 'generator' engines so they go from dead stop to full RPM and stay there the whole time during operation. Something I would not do, but designed to be RPM bullet-proof? Also, they survive 18-year-old Bundeswehr driver/operators
(paging Andreas)
Cab control
Top Speed - With highspeed axles and 395/85-20s my never exceed speed is a finite 68mph. It seems most happy at 62mph (all speeds listed are GPS confirmed). Even when trying to drive at 55mph for better fuel economy it natural creeps up to 62mph. But even downhill, tailwind max throttle, 68 is it. I am guessing the drag overcomes everything else.
Hills - Sometimes when a not so long hill is started at the perfect speed/rpm an almost 'normal' climb is possible (shocked face). But normally with any sort of long/steep grade (lots of those out west here), it will slow down to 40-28mph. Never slower than 28, as that is in 3rd gear. I've found this not too much of a hassle as I am still at the speed or slightly faster than the Class 8 trucks, so I just become one of the many trucks chugging up the hill, but not holding anyone up.
Noise - Triplecab so a lot more room for noise to dissipate, but for reference. First, this is the only vehicle I have that does not have any wind noise with a window open. Even with just one, no drumming, whistling, etc. Kind of freaky in a good way. Even my CLS can't be drive without noise with only one window open. A normal conversation can be held at cruise speeds, with the biggest problem is just the distance between the drive and passenger. That said, I use noise canceling headsets/plugs to listen to music as it is so much clearer. Of course, you have to check state by state if that is legal. Here in Oregon, both (canceling and music) are legal. Of course, common sense dictates to run the volume so you can still hear sounds from outside (horns, sirens, UFO tractor beams locking onto your truck, etc)
"not run the engine at high revs continuously"
Again pertaining to the OM352, my understanding is these were/are also 'generator' engines so they go from dead stop to full RPM and stay there the whole time during operation. Something I would not do, but designed to be RPM bullet-proof? Also, they survive 18-year-old Bundeswehr driver/operators
(paging Andreas)Cab control
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VerMonsterRV
Gotta Be Nuts
Thanks guys, I definitely do not have the cold start on my truck. It does start, just takes a bit of coaxing (and then a rather large smoke show). We should be heading to N.C. in the next few days so it should be ok to wait for the heater to get installed (hopefully get the truck back on Wednesday).
As far as noise, I have never liked driving with the window down. Heck, I don't even like the blower noise. The rest of the truck is now fine with the sound deadening and was a great improvement. Once the build starts to settle down a bit I will return to this and see if I can figure out something. I do have the truck at the welder/fabricators now and he is going to look at the A/C compressor install (just to give me an idea of time/cost) for the compressor, once done the subframe modification. Would wait to do the A/C till next spring, but that would reduce the need for the blower.
Mog, your top speed really sounds similar to mine now. Wonder why the online speed calculators seem to be over estimating the speed. I have emailed a company that says they make custom ring and pinion gears for trucks. Curious as to how expensive they would be. Will probably wait until the truck is a bit heavier to see how it does on the hills.
As far as noise, I have never liked driving with the window down. Heck, I don't even like the blower noise. The rest of the truck is now fine with the sound deadening and was a great improvement. Once the build starts to settle down a bit I will return to this and see if I can figure out something. I do have the truck at the welder/fabricators now and he is going to look at the A/C compressor install (just to give me an idea of time/cost) for the compressor, once done the subframe modification. Would wait to do the A/C till next spring, but that would reduce the need for the blower.
Mog, your top speed really sounds similar to mine now. Wonder why the online speed calculators seem to be over estimating the speed. I have emailed a company that says they make custom ring and pinion gears for trucks. Curious as to how expensive they would be. Will probably wait until the truck is a bit heavier to see how it does on the hills.
Sitec
Adventurer
To work out your diff ratio, count the number of tailshaft/propshaft revolutions to 1 full revolution of the road wheels. Chalk mark on base of rear tyre and corresponding mark on the propshaft. with a trusted friend in the cab and you viewing safely from beside the vehicle, drive slowly forward counting the shaft turns until the wheel has completed one full turn... 4.7 prop turns to one wheel turn = a 4.7:1 diff ratio. Also remember that the more you push these older trucks over 100kph the more they drink. Fuel consumption goes up drastically.
Re ether starting aids, don't go there. The knocking and banging you hear on startup is detonation of the starting fluid (and not proper combustion), which puts massive stress on dry big end bearings, aluminum pistons and piston rings. Older engines become reliant on it. Make sure you have decent batteries, and either fit a block/grid heater as previously discussed or a thermostart.
Re ether starting aids, don't go there. The knocking and banging you hear on startup is detonation of the starting fluid (and not proper combustion), which puts massive stress on dry big end bearings, aluminum pistons and piston rings. Older engines become reliant on it. Make sure you have decent batteries, and either fit a block/grid heater as previously discussed or a thermostart.
VerMonsterRV
Gotta Be Nuts
Thanks Sitec for the instruction on how to figure out the ratio. After reading your explanation it makes sense.
My plan is to have a single Webasto furnace supply heat to the habitat and also be able to pre-heat the engine via a coolant to coolant heat exchanger. Also hope this will allow me to heat the habitat (and domestic hot water) using engine heat in cold temps. Will see how this works out when i get to that point in a few months.
My plan is to have a single Webasto furnace supply heat to the habitat and also be able to pre-heat the engine via a coolant to coolant heat exchanger. Also hope this will allow me to heat the habitat (and domestic hot water) using engine heat in cold temps. Will see how this works out when i get to that point in a few months.
VerMonsterRV
Gotta Be Nuts
Hey all, a bit of an update. Got the truck back from the welder with the modifications complete (the guy really did a great job, you can not tell anything changed except that it fits now ). So we got the habitat bolted on.
As you can see we got to try out the new tires in snow... So we loaded up our tools and headed south to North Carolina, where our home (the boat) is. We need to get the boat back in the water and then find a garage we can rent for the winter so the build can continue. The trip went pretty smooth though I have noticed the truck is a bit more reluctant at highway speeds (guessing wind resistance), though still able to keep 55mph, just had to work harder.
This was the first real drive with the cab upgrades in place (air seats, sound deadening and stereo). I glad to say the changes were worth it and have made it way more enjoyable to drive (plus the SRW conversion helped smooth the ride). Funny to note, along the east coast of the USA there are quite a few toll roads. They charge by # of axles and if you have dual rear wheels. Got some odd looks from the toll booth people as they realized we only had a single axle with single rear tires. Same price as a car.
). So we got the habitat bolted on.As you can see we got to try out the new tires in snow... So we loaded up our tools and headed south to North Carolina, where our home (the boat) is. We need to get the boat back in the water and then find a garage we can rent for the winter so the build can continue. The trip went pretty smooth though I have noticed the truck is a bit more reluctant at highway speeds (guessing wind resistance), though still able to keep 55mph, just had to work harder.
This was the first real drive with the cab upgrades in place (air seats, sound deadening and stereo). I glad to say the changes were worth it and have made it way more enjoyable to drive (plus the SRW conversion helped smooth the ride). Funny to note, along the east coast of the USA there are quite a few toll roads. They charge by # of axles and if you have dual rear wheels. Got some odd looks from the toll booth people as they realized we only had a single axle with single rear tires. Same price as a car
.