Hello, I need to help a friend reseal his M104 on his 1995 E320 for oil leaks and a bad head gasket. I've worked on M103s and feel very comfortable around that motor, but this is my first time doing an M104 and had some questions.

Here are my parts list that I have gathered thus far:

104 010 3720 – Head gasket kit
104 010 2130 – Valve cover gasket kit
003 159 6703 – Spark plugs x6
104 990 0012 – Cylinder head bolt x14
102 016 0376 – Cylinder head bolt washer x14

I am wondering if I am missing anything else?

Is it necessary to replace the timing chain tensioner and guide(s)?

I always sent my M103 cylinder heads to get the valve stem seals replaced, should I do this too on the M104?

Any other gaskets I should replace while I am at it?

Thanks in advanced.

John,
We did a head gasket job on my '93 320CE recently. The car had 190K. It didn't need any machine shop work nor did the cylinder walls show any wear! Don't have the parts list close by but make sure your new head gasket has the metallic reinforced corners or you will be doing the job again.
Anziani
'93 320CE 205K
'95 E420 125K

You'll want to replace the two rubber hoses that connect under the center of the intake

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Intake and exhaust manifold gaskets if you plan to remove either.

What's the mileage on the engine? Chain tensioner can't hurt, and easy to do it now.

Is the front timing cover leaking? Maybe redo it as well?

How's the short hose from the head to the water pump look? Also easy replace now.

hello,

i tried google-ing the head gasket kit, but i really could find any decent pics of what the kit consists of.

1) make sure to buy head gasket kit from the dealer. if for some reason you cant then at least make sure that the head gasket is made by the company Elring, they make the genuine/updated head gasket.

2) spark plugs: Bosch F8dc4 (or equivalent, just remember copper cores only)

3) see the following post for a ton of good info on head gasket replacement:
My head gasket replacement notes (long) - M104 '95 E320

A) washers are not necessary: see post#3


B) both crankcase breather hoses (found on black plastic intake , near #2 cyl) should be replaced.


C) timing cover U-seal should also be replaced if not included in head gasket kit

Timing chain tensioner , i am not sure, my personal advice would be if its still good why replace it . the timing chain guides are accessible only by removing the lower timing chain cover. check the chain for stretch, if there is more than 5degrees then replace chain along with tensioner and chain guides. (NOTE: am not 100%sure if 5degrees is max allowed stretch, it may be more or less)

Another thing to replace if not included in head gasket kit, intake manifold rubber gaskets.

valve cover gasket:
a while back i replaced mine with a victor reinz kit, am not satisfied, leaks oil to spark plug holes, so go with a genuine kit if possible.

good luck

Do you have a picture or part number of this so I can find it in the EPC? What do these rubber hoses connect to?

Intake and exhaust manifold gaskets look to be included in the head gasket kit. Mileage is somewhere around 150k miles. Haven't checked the front timing cover on the motor, but if it is leaking I will for sure replace it as well as the chain guides and tensioner it seems.

As far as I know, the washers are needed if the head bolts are unflanged. Otherwise if the head bolts have flanges on them, I do not need the washers. I know this from my M103/M102 experiences, is this the same with M104?

Thanks for all the tips guys.

Another question I had:

I am looking in the EPC and the chain guide says this: " *** Item no. not valid for this model des."



Can someone clarify? Does this 1995 E320 not use the traditional plastic chain guide that is seen on M103 motors?

I'll add these are an utter pain to get back on, so replace them while you can.

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hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

When I replaced the head gasket in my M104 nine years ago, I don't remember replacing any washers under the head bolts. And further - many members will agrue with me about this - I reused the head bolts with absolutely no problems. I've put 50K on the engine since then. MB engineers allow reuse of the bolts and mine were within stretch limits.

__________________
95 E320 Cabriolet, 159K

i agree with all of the above. i remember being shocked that the bolts were not stretched at all, so i reused them, they all measured in very close to 160mm(new bolt length) the max length allowed is 163.5mm. i also do not remember replacing washers. its been 23,000 miles since and have not experienced any internal coolant leaks or oil leaks at head gasket, nor oil contamination of the cooling system.

good luck

Hose
MB# 1040943582

Hose
MB# 1040943682



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