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OM352 Horsepower Increase

34K views 30 replies 11 participants last post by  FEF 
#1 ·
I just brought my 1987 U1000 over from Germany and I'm starting my overhaul. One of the first things on the list is a little more juice. The OM352 engine is currently set for 76kW... how does one go about dialing it up??? My local Unimog (Freightliner) dealer dosen't inspire much confidence...) Can this be done at an injection pump shop? Any help would be greatly appreciated !!!:)
 
#2 ·
Yes this can be done at a pump shop or you can do it yourself. From what I've looked at on mine it seems the cab would need to be tilted to access the rear of the injection pump. you will want to install a pyrometer in your manifold or weld a bung immediately after the manifold to measure your exhaust temps to keep from damaging your engine.
 
#7 ·
I will be inspecting (with a borrowed bore-scope) my 352A in my U1200 tomorrow (I know its Xmas day, but you have to have something to do in between presents and dinner) to see if it has the plugged bosses for the piston cooling squirters. I will let you know my findings.

If I find the bosses I will buy the squirters and the bigger oil pump and crank up the fuel.
 
#12 ·
Well I finally had a look in my engine today, and bad news. The oil pick up is right above the drain, so I could not get the bore-scope past it. I still don't know if I have squirters, plugs or bosses. I did read in my manual that its only from a certain engine # that has the oilers and my # is not the one, so I guess I am SOL.

I might try again next time I have the valve cover off for a valve adjust, I might be able to get the bore-scope down from the top. If I ever find out for sure you will be the first to know.
 
#15 ·
I found this on the archives.
On Nov 25, 2004, at 4:45 PM, Chris Willsey wrote:

Quote:
[The early OM352 turbo motors did not have oil spray on the pistons. I
think you can go up to about 170HP without and not have a problem. Of
course having them is better than not.]

Mid 1977 they started using a block casting that has provisions for the
spritzers, even when not installed. They just use a plug and seal ring
in the spritzer location. All the Brazilian built 344 motors (locally
produced 352) that I have encountered are set up for them as well.

Jack Russell

Not to say that this is law, but it is Jack for what it's worth. Also http://mogmsgexch.com/ is back up again so you can use it to search the mail list archives.
I'm curious if any of your sbu mogs dont have the machined and plugged bosses.
 
#16 ·
That's GREAT the archive is back up, I learned a ton there.

There's potential for some good power to be made, it just takes money. I've been hot rodding Cummins diesels for 10 years, since I was 18. I have my doubts that the 352A is as overbuilt as a B5.9 but for short duty cycles I bet 250-300hp would be alright.
 
#17 ·
No piston oil cooling ports on my 1981 OM352

I just had to know
did i have machined ports for piston oil coolers or not?
a full day to drop the pan to find NO piston cooling jets or ports with plugs; the bosses are there on the block it appears, but i ain't doing that job without pulling the engine

more pain to drop the pan than i thought, drop the oil filter, the 12V alternator i have, the power steerrign pump, and the sway bar

1981 stock OM352 ex german U1300L, upgraded with Turbo last fall

Jimo
 
#18 ·
Hmmm... interesting. No problems with the install ??? Did you engineer it or have it done ? Aftercooler ??? Do you know if there is any kind of oil restrictor in the turbo line ? What kind of boost pressure are you running ??? Stock injectors ?? Did you expect this many questions ??:eek:

Sorry just curious... Good job !

Thanks !
 
#20 ·
sdo said:
Well I finally had a look in my engine today, and bad news. The oil pick up is right above the drain, so I could not get the bore-scope past it. I still don't know if I have squirters, plugs or bosses. I did read in my manual that its only from a certain engine # that has the oilers and my # is not the one, so I guess I am SOL.
Did you ever get a chance to look up the #'s on which engines have the squirters and which don't. I am thinking of picking up a turbo engine for one of my projects, so I want to make sure I get one with squirters.
 
#22 ·
I looked in my manuals last night, in the engine lubrication section. It says oilers are installed in engine # 353.958 and 353.959 from engine # 528 530. My engine dose # is before this so no oilers for me. I am still interested in finding out if the block is tapped for them.

Hope this helps.
 
#23 ·
sdo said:
I looked in my manuals last night, in the engine lubrication section. It says oilers are installed in engine # 353.958 and 353.959 from engine # 528 530. My engine dose # is before this so no oilers for me. I am still interested in finding out if the block is tapped for them.

Hope this helps.
??? could you clarify what this mean? Type 353.958 & ... 959 makes since but where does the 528 530 come into play? Course I'm not looking at a full engine number and this may be why it's not making since to me.
 
#26 ·
mmy hope too was that they were tapped and then plugged with some sort of sealing plug; no such luck

BTW i found the paperwork for my stock turbo kit, i paid some 2400 euros in 2002and installation was very straighforward and un eventful

it helped to do the electric fan refit as i mentioned somewhere else on this list, the air intake crosses in front of the engine and gettign rid of the fan pulley mechanism was nice, not sure absolutely needed as i did it before the turbo job


ive since fired it up but have yet to take it on the road, doign an engine brake install so some muffler work remaining
 
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