PorKen

Oops. Lost my mind. It's 1° cam advance.

SharkSkin

So, I may not have been clear with what I meant to say -- If, with the crank at exactly TDC, both cams line up perfectly with the marks, that's not always the case. I would venture to say it's rarely the case.

SharkSkin

Yeah, Chilton's manual are very high quality -- kindling, that is...

mark kibort

2degree movement of the crank is going to be 1 degree on the valves. good catch. i forget that the pully on the crank is the little tiny one behind the harmonic balancer. one rev on the crank = 1/2 rev on the cams.

MK

toofast928

Just a follow up to this thread.
How I got the cams to align was an offset key grinded to the 16v size (4mmx4mm). Took me 2 trys and 1 hour.
My left cam was advanced 2 deg. Right cam was on the mark.
I ended up using a Ford 2.4L offset key by 1 deg. Now both cams are synchronized and advanced by 2 deg.

marton

Me too.

It is hard to see the marks. I painted the slot with nail varnish (do not ask the colour) and I slid a long thin screwdriver in the tooth trough to check the correct point.

Marton

atb

toofast, can you get the offset keys at a parts store or did you have to go to a dealer?
I've doing a tb/wp job on an 84 right now. I'll check the TDC mark on the balancer and see if I get the same result as you did.

PorKen

GlenL did the same but with cut down Mercedes woodruff keys. Mercedes keys can be used as-is on 78-79.


more

I'm really am going to have to install the '79 cams I have into the '81 this summer, or it's going to be too slow compared to the '86.

atb

Thank Porken,



Is the third column crank or cam degrees?

I'd like to be able to estimate which part # I'm going to need by looking how far off the cogs are without pulling out the degree wheel. If I can see that for example, the cog is 3/4 of a tooth off, would part # "01 67" be the one I'm looking for? (Showed my work below for extra credit)

Maybe add a fifth column to the above chart for easy reference indicating:
04 - .46 cam tooth width
02 - .6 cam tooth width
01 - .73 cam tooth width
0 - .86 cam tooth width

PorKen

Mercedes#: 621 991 0* 67

* | Offset | C° _% | ±1 %
4 | 0.7mm| 7° .46 | 8° .53
2 | 0.9mm| 9° .60 | 6° .40
1 | 1.1mm| 11 .73 | 4° .27
0 | 1.3mm| 13 .86 | 2° .13

%: fraction of a tooth
±1: one whole tooth + key
one cam tooth is 15 crank°

atb

Nice!

Enlarging, printing, and going into my shop manual.