Author Topic: Tach pickup rubbing...  (Read 1962 times)

1980sdga

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Tach pickup rubbing...
« on: 26 May 2011, 12:30 PM »


The stud on the balancer is shiny and scored  :(  Since the surface is shiny this looks recent. 

I'm thinking that either the balancer is loose or the tach pickup has moved.  Is that squared off cutoff in the balancer normal?

This is a 1980SD

I'm shutting the car down until I get this worked out  :'(
Jon


Little by little I have grown fond of the infamous Auto Temp II we have in our 116's

Big_Richard

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Re: Tach pickup rubbing...
« Reply #1 on: 26 May 2011, 03:18 PM »
i would check the mounting bracket of the pickup device and make sure its not deformed or the pickup device has moved some how, I guess its also conceivable that the dowel pin has also shifted outwards though i find that highly unlikely as I'm sure its inserted in there with tons of force.

1980sdga

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Re: Tach pickup rubbing...
« Reply #2 on: 26 May 2011, 04:14 PM »
I think that's where I'll start. I need a socket to fit the balancer bolt for when I adjust the valves anyway.  I'm assuming there is a clearance that must be set with a feeler gauge?
Jon


Little by little I have grown fond of the infamous Auto Temp II we have in our 116's

calvin streeting

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Re: Tach pickup rubbing...
« Reply #3 on: 26 May 2011, 04:18 PM »
a m110 can be turned using the alternator 20 something bolt. Just add a bit more tension with your hand, also could remove sparks as makes tuning engine easyer (i used to do this when doing tapet adjustments)

1980sdga

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Re: Tach pickup rubbing...
« Reply #4 on: 26 May 2011, 04:30 PM »
a m110 can be turned using the alternator 20 something bolt. Just add a bit more tension with your hand, also could remove sparks as makes tuning engine easyer (i used to do this when doing tapet adjustments)


Thanks! I may try that.

What's a "spark"   ;D ;D
Jon


Little by little I have grown fond of the infamous Auto Temp II we have in our 116's

jbrasile

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Re: Tach pickup rubbing...
« Reply #5 on: 26 May 2011, 09:35 PM »
Jon,

I think Calvin is refering to the spark plugs which of course you don't have in the 300SD, because of their high compression,  diesel engines are REALLY hard to turn by hand. Check the service manual library and it will probably tell you how to do it.

Tks,

Joe

Big_Richard

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Re: Tach pickup rubbing...
« Reply #6 on: 27 May 2011, 04:38 AM »
um yeah, the compression ratio on a diesel will make it virtually impossible to turn by hand - if you try on the alternator bolt youd sheer it off   8)

calvin streeting

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Re: Tach pickup rubbing...
« Reply #7 on: 27 May 2011, 04:58 AM »
oops.. sorry didn't notice was a diesel ... stupid is me... :)

Squiggle Dog

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Re: Tach pickup rubbing...
« Reply #8 on: 27 May 2011, 05:58 PM »
You can turn the engine by hand with a 22mm box end wrench on the power steering pump pulley nut. It won't take much to turn it over. Just be gentle and don't ever turn it counterclockwise. If the pulley slips a bit you can press on the belt to give more tension.
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1967 W110 Universal Wagon, Euro, Turbo Diesel, Tail Fins, 4 Speed Manual Column Shift, A/C
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1980sdga

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Re: Tach pickup rubbing...
« Reply #9 on: 27 May 2011, 06:27 PM »
I'll have to check it out when I get home next week. I need a socket to fit the balancer bolt so I'll swing the crank around and check the clearance between the stud and pickup. Probably not a bad idea to make sure the balancer bolt is tight. I can't see any runout when the engine is running so I doubt that has anything to do with it.

It doesn't look like the outside of the tach pickup has moved but maybe a component inside slipped down  ???  A feeler gauge should tell me something...
Jon


Little by little I have grown fond of the infamous Auto Temp II we have in our 116's