odd alternator alignment problem. 1979 300D non turbo - PeachParts Mercedes-Benz Forum

subiracer06 · #1 10-30-2011, 02:45 PM

hello again,

car - 79 300D non turbo

most recent issue is sqealing alternator belts. here is what i have done so far:
-checked alignment
-replaced belts
-replaced alternator

when I removed the alternator pulley, i noticed that the 2 piece pulley was not even sitting on the keyway. It was spaced out all the way to the threads. is there a reason why my alignment would be off that far? I tried playing with it for a while but the actual alternator is hard mounted to the block, so what would cause it to be that far out of alignment? I am assuming it has been this way for a long time because there were several sets of belts in my trunk when i bought the car.

I have done a lot of reading on here and have seen generally that most turbo 617's have the duel belt/pulley setup; mine came with the single belt setup. I had also noticed a lot of posts mentioning a tensioner, mine just goes from the alt, to the pump, to the crank. Is that correct?

The keyway slot cut out of the pulley halves are damaged so it was very hard to get centered by freehand when re-installing. Are they supposed to be spaced all the way out to the end of the shaft? is the pulley supposed to be 2 pieces? And what size cont. Belt should I be running?

Where can i buy new pulleys? Every auto parts store i have been to does not carry them, and inisist on using the original...

Thanks in advance,

Jimmy

kerry · #2 10-30-2011, 03:02 PM

I don't understand the 'two piece pulley'. Maybe someone else does.

vstech · #3 10-30-2011, 03:42 PM

some of the 240D and N/A 300D alternators the pulley is actually two convex sections bolted together, there are washers and spacers to keep everything correctly aligned.
if yours is damaged, I'd start looking for a replacement. you could also upgrade to the dual belt design from a turbo 300. you might as well take the plastic fan if you find a setup with it.
all you'll need is the alt pulley, the water pump pulley, and a set of belts for the year vehicle you take them off of.

barry123400 · #4 10-30-2011, 03:44 PM

Junkyard maybe a good source. Pulleys can be expensive new.

subiracer06 · #5 10-30-2011, 05:17 PM

at the local pick and pull's i noticed every one of them with a dual belt setup... ok ill convert it then. these are all direct repalcements correct? and fan is for less rotational mass correct?

what size belts will i need for the convertions? will this be a same setup for say a 300SD if i order a complete set?

whunter · #6 10-30-2011, 08:43 PM

Here is a picture of the pulley assembly.

subiracer06 · #7 10-30-2011, 09:22 PM

That would be for a single pulley right? That looks very similar to my current 2 piece single pulley setup... The two belt system is just a slide on and bolt down of I remember what I saw at the pick and pull

1980sd · #8 10-30-2011, 10:35 PM

Is the crank pulley the same for both systems?

vstech · #9 10-30-2011, 10:50 PM

Quote:

Originally Posted by 1980sd

Is the crank pulley the same for both systems?

I think it is, but now that I think on it, I don't see how a 10mm dual pulley could work on a crank pully designed to spin a single12mm pulley... before you purchase alt and WP pulleys you better check the crank pulley.

subiracer06 · #10 10-31-2011, 10:02 AM

will do. i have seen on other threads that people are changing the front crank seal when replacing the crank pulley. is this necessary?

whunter · #11 10-31-2011, 10:35 AM

Quote:

Originally Posted by 1980sd

Is the crank pulley the same for both systems?

NO, the crank shaft pulley is different for single and dual alternator drive belt.

.

vstech · #12 10-31-2011, 02:56 PM

Quote:

Originally Posted by whunter

NO, the crank shaft pulley is different for single and dual alternator drive belt.

.

is the dual belt crank pulley going to work with a N/A a/c and Powersteering belt alignment?

whunter · #13 10-31-2011, 03:53 PM

Quote:

Originally Posted by vstech

is the dual belt crank pulley going to work with a N/A a/c and Power steering belt alignment?

NO.
Been there, done that.

The water pump pulley, power steering pump Bracket and vacuum pump must be changed to the newer 1981 - 1985 turbo version.
Can't recall if the A/C lined up, compressor was junk and owner didn't want it fixed.

subiracer06 · #14 11-01-2011, 09:12 AM

oh wow really? **** i guess ill try to find the correct fitnment for my original. im going to buy a new set of pulleys from MB