The #14 head on the 603, really bad? For sure?
 

Careful of the # 14 head. Look for a # 17. I keep hearing these things. I've read this thread (awhile ago) http://www.peachparts.com/shopforum/diesel-discussion/103444-have-theory-603-14-head-fractures-part-1-a.html?referrerid=19742

It's a good one.

But are there any statistics to support these claims that the #14 head is "junk?" Failure rate for those produced, miles when fail, anything? I'm not saying they don't crack, I just want to know how many really do crack. It's like Pit Bulls: they attack a kid, the whole nation hears about it, but a Golden Retreiver mauls a kid and that'll never make the news. I wonder if that makes sense... Statistically, Pit Bulls are the 7th (or thereabout) most "people friendly" dog breed.

Every car I've been looking at to buy has been a 14, unless it's been replaced. I don't to scared off of a potential good buy becuase people are scared of Pit Bulls.

Thanks all,

B

The problem is that when the Pit Bull bites he won't let go till the full moon comes around. When that #14 head bites it won't let go until it sqeezes a couple or three grand out of your wallet.

Several people here have posted that they have gone well over 200K miles on an original #14 head. When I find the right car (again) I won't let that #14 head stop me. If I see the right deal on a car with an upgraded head, I may buy the car just to get the head.

I agree, there are lots of #14 heads still on the road and running fine.

GSXR might be able to venture a more accurate guess but I'd say, from what I've seen, 5-10% of the OM603's will experience "crack head" issues at some point in their lives.

I would not let a #14 head stand in my way if I say a nice OM603 vehicle that I wanted in my garage.

I'd willing to bet that most if not all #14 head cracks are caused by allowing the engine to overheat. Does everybody know for example that you're not supposed to shut off the engine immediately after driving but give it a little bit of a cool-down time? A lot worse is when a dumb-ass driver keeps on driving with the temperature gauge in the red. Like any other head this head is simply vulnerable to overheating, but a bit more than the others.

My 1987 300D has 205k on it with the #14 head. It runs excellent and has never exhibited any problems whatsoever. The radiator hose is soft when cold and the coolant (MB only) is replaced regularly. BTW, the car never goes much above 80 deg C at any time. It really is a nice engine and I agree with everyone else.. don't let a #14 head scare you away. There are too many good ones out there as proof! :)

Oh, I think many problems on these cars are indeed related to the failure to cool the engine down after running at high turbo boost. I always make certain that it idles for at least 30 seconds before shutting it down. Especially after a run on the freeway....

The original head design is prone to cracking. This does not mean that they all will, but they are MUCH more likely to do so that later versions. They are also (like the #17 head) more likely to blow the head gasket between #1 cylinder and the chain case. Many won't, but a fair proportion will.

Just be aware that overheating WILL bust a #14, and be prepared to spend some money to fix it when it does. Otherwise, no problem.

Peter

I agree with PSFRED.. overheating will crack a #14 head for sure!!! Don't ask me how I know..... it wasn't the Ivory 300D! :rolleyes:

From someone who just had his -14 head go through the slow, strange death spiral, and it is looking at a major parts bill, I would make damn sure that you really want a 603 powered car, rather then a 602, 606, or even a gasser (Blasphemy I know).

I knew about the -14 head issue, and rolled the dice on my 87 300D, the car appeared to be in great shape, there was no evidence of impending failure, and the paperwork showed the cooling system and the car in general to be well maintained. I decided that I wanted the car, even if it was likely that I would have to replace the head.

Now that I am actually faced with the expense of replacing the head, and the time loss associated with performing the work, I really wish I had not bought a 603 engined Benz. I am undecided on what I am going to do with the 124, but I think the 190D that it was supposed to replace, just may be sticking around in it's place.

There was a time I was as down on my 603 as Mack is now. When I bought my SDL, I was not as careful about researching the head issue as I should have been. The head had supposedly been replaced only about 100,000 before I bought it so I assumed all was okay. Unfortunately, I lived quite a ways from the seller, so we met in the middle. Therefore, I did not have a chance to check for cold pressure in the cooling system and was even too stupid to check the casting number. All was fine for about the first 5000 miles I drove it, then it slowly started to lose coolant. In that time I can say absolutely for sure it was not overheated. But, as time went on my coolant use increased and eventually led to replacing the head with a -16 casting to the tune of about 3,000 in total. At the time I was about ready to roll the car off into a ditch and throw a match in it, but I have since had at least most of my faith restored in it (except for all the little things the idiot mechanics screwed up that I have had to fix).

Moral of the story is that I wouldn't let the -14 head completely turn you off to the 603 engine in general. But, before purchasing, be sure to check for cold pressure in the cooling system. Also take the head into account when setting the purchase price. Be aware of the fact that the day may come when you need to drop that 3,000 for a different head. You can name problems with almost any engine ever manufactured. You just have to make a calculated gamble and increase your odds by doing your homework and being prepared.

I think you just have to bite the bullet on this one. Shop around and find the best deal on a head and try to keep your costs down. The only way to get a return on your investment is to drive the car for many miles. You bought the car for that so do it.

The only alternatives are to sell the car for junk price or rip-off some flat-foot pilgrim. Better to not go there.

I guess you could break the car and sell the parts on eBay. That sounds like more work than fixing it.

We all sometimes buy things we shouldn't, and take our lumps, just part of life in the big city.

My 14 head is moving right along, I am expecting 243k soon. I don't worry about it my cooling system is perfect, so no chance of overheating. A 14 head is just something you have to respect.

I survived the head replacement and trust me if this wagon hadn't been so hard to find in the first place I probably would have let it go, but I'm sure glad I didn't. My failure was certainly due to over heating. My viscous fan clutch was failing to engage and allowing the car to run warm. I never personally drove it in the red, but I'm sure the PO did.

Please vote in the survey I posted while I was in recovery over my head replacement:

http://www.peachparts.com/shopforum/diesel-discussion/33066-603-96-engine-head-crack-survey.html

I think the best advice is to try to avoid one that is already exhibiting the cracked head symptoms or negociate the head replacement cost into the deal and then take care of it like the guys on the form suggest and chances are good that you'll enjoy your car for a long time. As the survey points out with 24 respondants so far. A cracked head is far from a sure thing.

Good luck,

My SDL had the "14" head. I'm not going to worry about it. I'll do all that I can to protect my head, but if it goes it goes. I love my car. I really enjoy it. I'll do what it takes to fix it. I've put about 45k miles on it and it keeps on ticking like the "Everyready Bunny".

All vehicles have problems, some more than others, but you can't worry every day about a head. You probably have a better chance of someone plowing into your car, than your head cracking.

Anyone have any preventative maintenance on caring for the head?
Any symptoms of a head cracking or going bad?

There can be any number of problems with a used car and the head issue is only one that is well defined as for repair. To me a more important issue is rust. Having lived in the rust belt for many years, I know that the life of the car due to salt is very limited. However, be careful in buying a "Southern" car as some dealers buy in the Rust belt and sell them in Florida or Arizona.
O.

From what I have read on this forum, it really varies from car to car. The one thing that seems consistant is cooling system pressure when cold, as in the next morning. The system will come up to pressure rapidly, prior to the coolant temp being high enough to be causing the pressure increase. (Dave M. has contributed a lot of info concerning this issue, if you have not read his posts, a search of GSXR is well worth the time. Thanks, Dave.)

My car started to run a bit warmer then normal at idle. It was irratic, sometimes staying in the same range as normal, other times it seemed just a tad higher then it should be. The first real tip was the hard rad hoses when cold, then I noticed it started to climb too rapidly at idle. Eventually it ran too hot, (not overheating) but just too hot for a 603 in good trim, and then it started to use some coolant, this was erratic as well, but once it was obvious it was going through coolant, I parked it. (Once the system goes into this mode, it can no longer recover coolant from the catch tank, unless you pop the radiator cap as soon as you shut down, so that as the system cools it can pull a vacum.) Popping the radiator cap on shut down will temporarilly elliminate most of the symptoms.