Determining engine year - PeachParts Mercedes-Benz Forum

JHZR2 · #1 04-17-2007, 10:29 AM

Hi,

My 300D is a 1985 model. Simple enough, right? Well, the tach doesnt work, and strangely enough, I also have a "vacuum box" on the top of my engine, just like my 83 had. And it has vacuum lines going in and out, just like m y 83 had.

The blue disc vacuum valve on the driver side fender is disconnected.

Everything works good, but I worry about the fact that the tach doesnt work, and that I have the vacuum box on top - as if I have an older engine perhaps...

Is there a way to use the identifying marks on an engine to determine what model year it is from?

Also, going back to my tach issue, since the car is in fact an 85, even if the engine itself is not correct, if the tach pickup for the computer is correct, then the tach and AC would be fixable. So, can anyone comment to me where exactly the computer pickup is on the 85 bellhousing (Ive not been able to see it locate it), and where it attaches on either end? It doesnt seem to plug striaght into the ECU computer.

It seems to me that if I have an incorrect engine, Im screwed, as both the tach wont work, nor will the AC system, if Im not mistaken. As of now my ACC unit is not functional (I knew this when purchasing), and short of replacing the engine/trans with an 85 model, Im stuck.

So, any insight would be most appreciated.

Thanks,

JMH

rkohut · #2 04-17-2007, 11:40 AM

It might be hard to nail down, except by process of ellimination. Maybe someone has some data on it.

FWIW, my 1983 300D (4/83) engine number is 051283. I think they made about 200,000 1982-1985 300D's. Can you see the engine number?

JHZR2 · #3 04-17-2007, 11:41 AM

any idea where it would be?? IIRC, its right on the front, maybe onthe head below the valve cover???

I dont know where to look.

Thanks,

JMH

DeliveryValve · #4 04-17-2007, 11:47 AM

Quote:

Originally Posted by JHZR2

Hi,

My 300D is a 1985 model. Simple enough, right? Well, the tach doesnt work, and strangely enough, I also have a "vacuum box" on the top of my engine, just like my 83 had. And it has vacuum lines going in and out, just like m y 83 had.

The blue disc vacuum valve on the driver side fender is disconnected.

.........

No black vacuum box came on the '85. With the blue vacuum pod disconnected, my guess is someone must of change the vacuum setup to the older setup.

Quote:

Originally Posted by JHZR2

So, can anyone comment to me where exactly the computer pickup is on the 85 bellhousing (Ive not been able to see it locate it), and where it attaches on either end? It doesnt seem to plug striaght into the ECU computer....

The bellhousing RPM pickup is located next to the oil filter housing just above (inch or so) the bellhousing bolt with a nut in the back of it (it is the only bellhousing bolt with a nut holding it).

DeliveryValve · #5 04-17-2007, 11:48 AM

Quote:

Originally Posted by JHZR2

......Is there a way to use the identifying marks on an engine to determine what model year it is from?.....

On '83 and later 617.95X models, you can find the year it was manufactured like "83" cast in front of the cylinder head.

Benzcrusher · #6 04-17-2007, 12:02 PM

The block is dated day/year, ie: 245 84. Look on the driver's side behind the IP just below the part# on the block.

rkohut · #7 04-17-2007, 12:11 PM

Quote:

Originally Posted by JHZR2

any idea where it would be?? IIRC, its right on the front, maybe onthe head below the valve cover???

I dont know where to look.
JMH

This is from Diesel Giant
http://dieselgiant.com/mercedes_engine_and_transmission.htm

The pics on the web site are a little dark. I've lightened em up a bit.

DeliveryValve · #8 04-17-2007, 12:44 PM

An easy way to determine if you have a motor that is not an '85 is to look to see if you have an ARV on the turbo. All '85s have an ARV on the turbo.

See diagrams of the different year setup. (The ARV is #71 on the diagram)

My hunch is that you have a different year engine in your vehicle and it is the exact situation as in the this previous thread in which you posted your questions before about your tach.

http://www.peachparts.com/shopforum/showthread.php?t=184219

JHZR2 · #9 04-17-2007, 01:16 PM

wow that is great, thanks so much!!!

I think that when they took out the blue disc vacuum trnasducer and whatnot, that they converted the vacuum system to the older style for the trans and whatnot to operate... Ill see later if that is the case or if I have something else...

In real terms, what would I be looking for on the turbo to signify an ARV? It seems that it would be another tube that looks like the one that goes from the ALDA to the banjo bolt, right?

Ill look tonight, and maybe post pics.

Thanks again!!!!

JMH

Cervan · #10 04-17-2007, 05:28 PM

arv stands for air recurulation valve right? meaning its like a egr? or do i have my words messed up.

JHZR2 · #11 04-17-2007, 08:11 PM

OK, got some information...

Head number: 617 016 03 01 M0 C8

Block number: 617 952 120 41 350 (I forget how the last bunch of numbers were spaced)

The head seemed to have an 82 rising from the metal surface, just up above where the couple of banjo bolts come in and out:

JHZR2 · #12 04-17-2007, 08:12 PM

No ARV hose either... looks like an older rebuilt engine in there.

JMH

rkohut · #13 04-17-2007, 08:26 PM

Quote:

Originally Posted by JHZR2

OK, got some information...

Head number: 617 016 03 01 M0 C8

Block number: 617 952 120 41 350 (I forget how the last bunch of numbers were spaced)

The head seemed to have an 82 rising from the metal surface, just up above where the couple of banjo bolts come in and out:

According to the block number you provided, your motor # is 041350

For reference my 82 300D is 014474
My 83 300D (April 83) is 051283

Looks like yours might be an early 83 or late 82
Also, your motor may have come from a 300SD

Are you sure it's a 85?
The 10th letter in your VIN should contain an F if it's an 85
like WDBAB33xxFxxxxxxx
a C would be 82, D is 83 etc.

DeliveryValve · #14 04-17-2007, 08:32 PM

Quote:

Originally Posted by rkohut

According to the block number you provided, your motor # is 041350

For reference my 82 300D is 014474
My 83 300D (April 83) is 051283

Looks like yours might be an early 83 or late 82
Also, your motor may have come from a 300SD

Block number: 617 952 120 41 350: Actually "952" is from a "D", "951" would be in an "SD"