603.96 Engine Head Crack Survey
 

There has been some debate on this and other forums as to the extent of the flawed 603 head failures. If you have owned a 603.96 engine (e.g. 1987 300D or TD or SDL) please reply to this poll.

Since the poll only allows people to vote once you'll have to post a reply if you've owned more than one of these engines.

Not yet, and I'm not worried about it. Most head failures were the result of the trap oxidizer contributing in overheating the engine, which is no longer an issue. Just keep an eye on the temp gauge and all's well.

There is speculation that the extra heat presented by the trap oxidizer contributed to this. In my case the trap was only replaced 18 months ago. So I think my head crack supports this theory. Any of the other broken heads had the traps removed late? Thanks,

Does anybody know what the overall percentage may be for the head failures to occur without overheating the engine?

And in what mileage band would this most likely occur? I'm currently at 100K with the SDL and have some oil leakage at the headgasket at the back of the engine. It drips oil from this area and is annoying but I've applied some JB weld at the seam last night hoping this helps without having to replace the head gasket. Fortunately, (knock on wood) I have no coolant or oil leakage internal to the engine.

Other than that, this has to be the finest diesel car ever produced by MB.

Herb
'82 240D
'87 300SDL

msyoder--

My trapox was removed at around 203k miles, the head cracked at 235k. Theory seems reasonable to me.

I am currently at 268k with no failure,

I do not see anything in the exhaust that resembles
a catalytic converter, but where in the exhaust system
is (was) it so I can be certain?

Thanks,

Craig Amos
1987 300D Turbo

Craig,

The TO was located on the pass. side of the engine in the exhaust line before the turbo. It was a large silver metal canister about 8-10" in diameter.

Lance,

The PO never did the trap change. I had it done at 217kmi and the head replaced at 242kmi. The correlation is strong in my case also.

Craig,

You can view before and after pic's of the TO removal at the following link:


:EDIT: bad link
http://www.dhc.net/~pmhack/mercedes/trapoxr.HTM

I'm at 262K now, no idea when the trap-ox was done, but I'm positive it was done while the car still lived in Cali, before 100,000 miles.

I have no signs of the head failing, I maintain my car religously, and watch the guages at all times.

Oh, and as far as I know the head is totally original and has never been touched.

Turbodiesel,

Do you have any external oil leakage, however minor, at the headgasket area? And if so, how bad does it leak?

Herb
'82 240D
'87 300SDL

Turbodiesel,
 

Unless you've put >165k mi on your engine in the past 5 years (not that it's not feasible), I doubt your trap ox was replaced before the engine hit 100k mi. The trap ox recall occured in Feb '97.

I've got 217K on mine and no known head problems yet. Engine runs good according to oil analysis. Previous owner went thru two radiators two years ago in the winter, dont' know if it overheated but that was at about 47,000 miles ago and no issus yet.

Well, to be honest, I don't know when the trap ox was done, BUT I have all of the service records since the car was in New Jersey, and that is at around 100,000 miles.

The car leaks some oil, and I never really cared enough to inspect where it's coming from.