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1984 406
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Discussion Starter #1
Well I have posed this question to a few via private message, but I thought I would put it to the herd. I have a stock 406 with an 84 hp 352 motor. It has seen some major neglect over the years from the P.O. I am getting geared up this summer to do some major surgery and trying to formulate a budget(I know, I know-you can not forsee everything and everything related to a unimog is expensive). I am considering removing the injection pump, having it rebuilt and turned up to the next level, from what I can tell that is approx. 110 hp. I am trying to find out an estimated cost from someone that has gone through this. I am talking about NEW everything including injectors. I researched the archives, but couldn't find any costs associated with this. Anyone with even some limited costs associated with this project would be appreciated.
Happy Holidays, Thanks, MUD
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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"THE COST IS TO DAMN HIGH". If it works, turn it up on the truck and enjoy. Oh, install a pyro first.
 

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1978 416.115
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A diesel fuel system (pump/injectors) should last the life of the engine they belong too, Doka is right to re-build with all new parts and injectors would cost a small bank acount 2k and up, Your best bet is to look for a pump off a SEE with 9mm plungers dont rebuild the wimpy 84hp pump and turn it up, find the 110hp 9mm pump It will cost you way less, as for the injectors just a simple rebuild will be fine. My 406 is a US military it came with a 110hp pump I'm very happy with it.
 

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'78 Mog 416.141 DoKa
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I am considering removing the injection pump, having it rebuilt and turned up to the next level, from what I can tell that is approx. 110 hp. I am trying to find out an estimated cost from someone that has gone through this. I am talking about NEW everything including injectors.
MUD, I'm late to the party with this as the info was on 'another' computer. Here's a compilation of 'stuff' from over the years pertaining to hot-rodding the OM352. A lot of this is from respected guys like Jack R and Kai. Some is fluff, some may be absolute BS - I'm simply providing it all with no filtering.

Note - Benzworld message board file size rules require me to break it up into multiple parts - sorry.

Enjoy.
 

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'78 Mog 416.141 DoKa
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I got a ton of it - from back in the Golden Age of Mog info (the "Russell years") ;)

I hope it helps someone.
 

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BenzWorld UNIMOG statesman
Unimog 404.1 Diesel (sold :( )1995 LMTV 1078
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In the ultimate Mog sticky -via- FAQ/DIY.... link there is a section that will take you to a long thread about improving performance of the OM352. Don't know how much is repeat but I added this thread into that section also.
 

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1984 406
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Discussion Starter #14
Why a pyro?

Very interesting reading material and advice. Another question arises though, through my complete ignorance of motors, why, if you are just planning on turning the injection pump up to say the next level of standard h.p. would you need to install a pyro? In my case, I am just considering moving up from 84 to 110 h.p., no turbo install or anything funky, why would you have to worry about such a thing if others came stock that way? I am just thinking about increasing my power output when I am in the timber or have a big boat hooked up I am trying to drydock for the winter. If I was trying to get the h.p. and speed increase needed to pass a bicyclist in say a 1/2 mile stretch, maybe I could see these "extras", please somebody make me understand.
Thanks, MUD
 

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1978 416.115
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Very interesting reading material and advice. Another question arises though, through my complete ignorance of motors, why, if you are just planning on turning the injection pump up to say the next level of standard h.p. would you need to install a pyro? In my case, I am just considering moving up from 84 to 110 h.p., no turbo install or anything funky, why would you have to worry about such a thing if others came stock that way? I am just thinking about increasing my power output when I am in the timber or have a big boat hooked up I am trying to drydock for the winter. If I was trying to get the h.p. and speed increase needed to pass a bicyclist in say a 1/2 mile stretch, maybe I could see these "extras", please somebody make me understand.
Thanks, MUD
They're only $90 and about 30 minutes to install.

I doubt you'd run into any issues driving around normally, but under heavy load (pulling a log, going uphill, etc.) you might hit some high EGT's. Which is why you want to increase it to 110hp.

I put one on mine and it was cake. Trust me, if I can do it anyone can. Toughest part is finding a NPT tap.
 

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1984 406
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Discussion Starter #16
They're only $90 and about 30 minutes to install.

I doubt you'd run into any issues driving around normally, but under heavy load (pulling a log, going uphill, etc.) you might hit some high EGT's. Which is why you want to increase it to 110hp.

I put one on mine and it was cake. Trust me, if I can do it anyone can. Toughest part is finding a NPT tap.
The taps and the fabrication are no problem here, just making my little pea sized brain understand what and why is where the problem is.
 

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mogless, except for my friends MB4-94. And a bunch of other diesel junk.
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I had my 416 injectors cleaned and rebuilt for around $600, and just had the injection pump for my Dodge (also an inline bosch pump) tweaked for another $500. It's making as much power as they could tweak it for without swapping in new parts (expensive). Not only is the truck more powerful, it's way smoother. Money well spent, IMO. And, X's 3 on the pyro.
 

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'78 Mog 416.141 DoKa
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The taps and the fabrication are no problem here, just making my little pea sized brain understand what and why is where the problem is.
Upon installation of pyro's, I recall some people have been surprised at the high level of EGT that it's possible to generate with so-called stock OM352's. The way I look at it is the pyro is inexpensive and simple and the ONLY way to know what is truly going on 'in there'.

[edit] uhhhhhh....no. I don't have one on my truck <shrug>
 

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The taps and the fabrication are no problem here, just making my little pea sized brain understand what and why is where the problem is.
I don't think there is a problem, and obviously if there was a problem you'd hear it on this board. There are a TON of 406/416 out there with no pyro's and no problems.

From what I've read, the OM352 can produce very high EGT's (even "stock") while driving up hills and under a lot of load, especially at higher altitudes. I put one on mine just because that $90 investment might save me putting in new pistons.

I mounted mine under the dash using some copper banding and 2 self tapping screws. You see it's about 38° right now :)

The 4th fuse was unused and also turned off and on with the key.
 

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'78 Mog 416.141 DoKa
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From what I've read, the OM352 can produce very high EGT's (even "stock") while driving up hills and under a lot of load, especially at higher altitudes. I put one on mine just because that $90 investment might save me putting in new pistons.
What's your motors rated HP, and what have you seen lugging up some of the local hills, floored in 6th ?
 
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