OM603 #14 Head - PeachParts Mercedes-Benz Forum

frankstallone · #1 10-26-2009, 08:28 PM

I am tired of 'searching' for #14 head on the OM603 to find information and finding posts that have little if no relevance. Can you guys help me out post some articles on how to find the serial # on the head/information about the head?

I know it 'fails' but some more information is not easy to find if you don't know the exact search terms. I never checked to see if my car had a #14 head but I re-hauled the entire cooling system (radiator, fan clutch, water pump) and the car never gets near 100C; however I might be going to look at a 300SDL (will be eventually I am sure) and would like to know here to look for the #14.

Thanks for your patience guys, every find in the search seems to say "look up '14 head' in the diesel discussion" which produces more of the same, or horror stories which I don't feel like reading.

jt20 · #2 10-26-2009, 08:34 PM

do you see the # 14 in this picture?

it is on the driver's side near the injectors and towards the front of the engine.

frankstallone · #3 10-26-2009, 10:21 PM

Yeah I see it here, is it visible from the engine bay though? I'll have a look 2morrow. =) (P.S. thanks for the photo)

C Sean Watts · #4 10-26-2009, 10:26 PM

Quote:

Originally Posted by kaiz3n

Yeah I see it here, is it visible from the engine bay though? I'll have a look 2morrow. =) (P.S. thanks for the photo)

It's near the #2 injector, you'll have to crouch down and look at eye level, almost with your chin on the fender.

Caseyjones955 · #5 10-26-2009, 11:11 PM

I have that #14 head on my 87 SDL also, educated speculation puts the car at 300-400k mi, most of which it was neglected. It runs quite well with catchup maintainance and doesnt over heat. I assume that someday I will have the issue but it has a helluva lot of use on it so far. I have read some pretty mixed stuff but so far so good. Im keeping an eye out for a cheap score on a better head so I have it if/when I need it.

C Sean Watts · #6 10-27-2009, 12:02 AM

here, "Has your #14 head failed?" IIRC it was something like 25% 'yes' --- I know someone will find and bump it up.

I was running over that with my engineer buddy over dinner. True 25% is a high failure rate even for a Yugo but if we account for situations like the trap/ox still on some of them or neglect and/or abuse IE: "Gee, honey/dad/mom/brother/etc, something is wrong with YOUR car, I had to floor it to get it home and steam came out of it."

Can we really account for every cracked head that "was never over heated" when we might not know 100%?

Jeremy5848 · #7 10-27-2009, 12:12 AM

Agreed. A #14 head that is never overheated is less likely to fail than a #22 (or whatever) later version head that is abused.

Desert Dog · #8 10-27-2009, 01:07 AM

Well thank you for that picture from another newbie here. I checked out my 87 300 SDL and sure enough I have the dreaded #14 head also....Mine has 318,000 miles on her but was supposedly had a re-build done at the 200,000 mark. I've only had it a month now but it runs fine except the #2 pre-chamber is leaking combustion pressure and blowing soot up onto the #2 injector. The #2 injector is partially fouled because it clacks at idle.
I've ordered injector heat shields and pre-chamber seals so all I need now is a slide hammer and the proper thread to pull the pre-chamber. Anybody have a spare bad injector I can use to make the tool? I'm in 29 Palms CA somewhat near LA.
I would be greatly appreciative of anyone willing to send me a bad injector or the proper tool so I can fix my baby. I'll return the tool when I'm done or buy it from you whatever is better. Theres not much around here and the closest dealer is in Palm Springs over an hour away. I really don't have large disposable income to buy the factory tool......

Steve

frankstallone · #9 10-27-2009, 08:59 AM

@Sean: Thanks I will do just that. It's raining today but honestly even if I have a #14 head I am not even the slightest bit worried. =)

@Jeremy: I agree with you will full confidence

@Steve: If nobody chimes in here check out the Tool Rental Program on the forums here; I have never engaged with anybody through this avenue however it seems promising.

xweezyx · #10 09-13-2011, 10:17 PM

I have a quick question on this subject. I've had a #14 engine that I've put about 20,000 miles on. Its at 307K right now. I have no idea about its entire history, but I know that the previous owner had to put a fan clutch on it, so i'm guessing it has overheated at least once. Is there a point in time where you are "home free" from getting a cracked head, meaning, if after say 20,000 miles of no overheating incidents, if it hasn't developed a crack yet, is there a chance that it will?

...I guess that wasn't such a quick question.

sixto · #11 09-14-2011, 02:17 AM

Quote:

Originally Posted by xweezyx

Is there a point in time where you are "home free" from getting a cracked head ... ?

Yes, the day it's no longer your car

Use a blank idiot light space in the gauge cluster for a warning when the aux fan coolant switch trips at 105*C.

Sixto
87 300D

winmutt · #12 09-14-2011, 08:50 AM

I'm of the opinion that if you have 300k on the head without issue, the chances of an overheat causing problems are minimal. I am also of the opinion that most are failed headgaskets misdiagnosed as cracked heads.

buffa98 · #13 09-14-2011, 10:59 AM

^^^^^
DITTO!!!

I cant remember who has it on the sig line but it is along the line of "worrying about a 603 with a #14 head is like looking down at Cindy Crawford because of her mole"

I have an 86 SDL with a 14 head that I have put 45K on since I got it. Do a flush make sure the cooling system is in good order and drive it!

If you develop a head/head gasket issue is because of the head of the fact the car is 25+ years old with 300 k on it?

My $.02

xweezyx · #14 09-14-2011, 10:24 PM

The aux fan light is a good idea. Thanks!