1993 Mercedes OM603 Build

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vinniehobart

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Picked up a 1993 Mercedes 300SD near home this halloween weekend for $1000. Put a new battery, tightened the loose exhaust manifold bolts, and fixed the valve cover gasket oil leak (someone didnt put it on right :doh:), put an cheap intake on it, straight piped it, and adjusted the ALDA slightly. All i can say about this car is my 340k mile f150 can trap faster 60fts than this thing. I have been talking with Dieselmeken and Diesel Pump UK across the pond about getting some 8mm elements for this thing. On top of that I think ill add a hx35 since Im told that it will bolt up to the stock exhaust manifold and still clear fenderwell. I bought the car for the Injection pump in the hopes of finding a OM606 motor and doing a mechanical om606 build. Now on to the business at hand, what would be a adequate injection pump shop to send my pump to have the 8mm elements installed and be bench flow tested. Im in central Illinois so I know there are probably some fairly close ones (TDI gets 50mpg so driving isn't an issue).
 
Needing to replace the Headgasket on this thing. Going to go get everything off peachparts. Doing Headgasket, prechambers, valve seats, and new head bolts. I need to see if id be able to get some ARP headstuds for this model of motor or not or just call them and see what I can do. Dont want to go back to headbolts since these are known for HG failure and it will be seeing 400hp very shortly
 
How can you assume the Head is bad if it isnt even a #14 head? I'm going to try and figure out what length of headstuds I need from ARP to make it work since they don't have a production kit. Im also searching for OM606 turbo connecting rods to swap out since motor will be out of the car.
 
Lucky you got a 18 head! They still crack though, a guy on STD has a cracked #20 and 21 on his bench. But it's rather unheard of for the newer heads to crack.
You can do 606 rods if you want, personally if it were mine id push the 603 til somethin gave, and be searching for a 606.95x in the mean time
 
I've seen some youtube videos of some nasty MB diesels over in europe. What are they running for fueling modifications? Some of them have a really nasty lope and sound like they are spinning 6K+ rpm's . Is there big injectors & pumps available like what a 12v cummins would have?
 
He's been talking to some of those guys. It's all pump mods and turbo/supercharger combos. They still run stock head bolts, springs, injectors and everything else. So imagine if we added all the usual parts we add to 12v's over here.
 
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Depending on how many rpms are run, upgraded valve springs are normally in place. And depending on how high hp you are wanting, custom rods as well. But stock rods will handle around 500 or so.
Stock fueling is provided by a 5.5mm IP in a 603 and 6mm in 606. Maximum adjusted fuel is around 90cc on a 6mm I believe. Pump builders from Overseas make pumps up to 8mm that put out 300cc+. Injectors can be extrude honed, but since it is an IDI, injectors are basically just a large hole anyhow. Prechambers are opened up larger Than stock as well.

Most drill an extra key way in the crank to keep it from slipping the stock key. And normally a tubular exhaust manifold is used, stock is too restrictive.
I'm probably missing a couple things, but that's what I have
Concluded from my research of others builds.
And they are pushing 6k+, they factory redline around 5.5k
 
I was going to get 8mm pump elements have flow 150cc of fuel and run a hx35 for now if the heads not jump. Ya I was planning on pushing this thing to atleast 400hp. I want a om606 car but wanted the M-pump. Bought the car for just the pump, and found out I enjoyed driving it
 
They are very nice cars to drive, I've driven some with 300k+ miles on them and they still drive nicer than a cavalier with 100k on it.
 
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Todays final conclusion. Not a blown headgasket like I thought. Oil is coming from valve seals. no cracks are noticeable in the head. We will be sending the head off to get cleaned and inspected. New pre chambers will be put in as well as injectors. Lifters looked good, so those will most likely be reused. 8mm elements in the Injection pump and removal of the fuel heater and mechanical lift pump in place for a electronic lift pump and a pressure regulator. I will be calling ARP in the hopes of getting some correct length headstuds to make this work for the OM603. I figured we can piece together a headstud kit fairly easy if I give them the dimensions needed. Also I will be running a certain 62mm turbo off a cummins powered Riviera on this as a single turbo. Hopefully the stock trans holds!!!
 
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