Distributor Body Very Difficult to Rotate
 

1978 280CE/ 110.984


This is a new one on me. I wanted to begin my Spring Tune-Up. Decided to start with adjusting timing. I loosened the Allen head tightening bolt and tried to wiggle the Distributor. It felt locked in place. I completely then removed the bolt and tried again. Still very solid in place. It seemed 'frozen' to the Bearing Housing. For the last 2 hours, I have slowly been dripping penetrant between the Distributor and the Housing. I have finally managed to get the Distributor to rotate, but with 'encouragement' from a screwdriver and a hammer, moving slowly one direction and then the other. I still can't say it moves freely at all.


I would really like to pull the Distributor out and see what is going on. No problem getting the engine to TDC and verifying TDC mark on the Distributor. Before I 'take the plunge' and get aggressive, I thought I would inquire here and see if anyone has ever experienced this issue, and how I should proceed.


As always, thanks in advance!
MM

Have a look in the vintage section, someone recently went through this.

As for penetrant, don't use WD-40 , it is a miserable lubricant. I use " Blaster " brand with good results.

The problem is corrosion between an aluminum distributor body and a steel adapter pretty much locks the two together leaving penetrating oil nowhere to go. ( There are cars with steel distributors / aluminum adapter ) If your distributor is steel and adapter aluminum, heating ( warming ) the aluminum can help.

In the vintage thread, the aluminum adapter was easily removable. This could be helpful as you can heat things away from the car.

A key points are: If you get any movement, stop then turn the other way. The goal is to work with the movement you have rather than forcing it past where it stops as this can jam things even worse. Initial movement will be very small and as you work things back and forth the movement will increase.

Don't hammer things apart, this can break casting.




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SL - Thanks for your Reply.


I finally got the Distributor out. It took a LOT of grunting and groaning. Not to worry either about damaging the Distributor Body or Housing. I was very careful and used a dead blow hammer to tap and rotate the Dist. one direction, and used a Philips (in other words, round tip) screwdriver to rotate the Dist. the other direction. I put the screwdriver between the slot in the Dist. where the adjusting bolt goes, and the top edge of the Housing. This gave me leverage to rotate.


I started with plain old Liquid Wrench, because I needed something very thin with a low viscosity to 'suck in' between the faces of the Dist. and Housing. Once I was able to pull the Dist. up about 1/4" and could see the top of the shaft, I started running some plain old 3-In-1 down into the Housing. I wanted to provide as much lubricity between the shaft and housing as possible. My thought was that the rubber shaft seal was dried out and was grabbing & binding.



From that point on, I just rotated back and forth as I pulled up. It was slow going. What I needed was leverage. Now don't cringe, but I grabbed a small crowbar and ***carefully*** got the hook end between the edge of the housing and the bottom of the Dist. All it took was some gentle leverage and the Dist. slid right out. No damage or even score marks to the surfaces. That rubber seal was hard and dry. New seal is on order. I will probably inspect and polish the shaft with some 400 and 600 wet or dry to get it mirror like, before reinstalling.


All this to adjust timing. :D

Ha - I just got Gute Fahrt translated and it did not mean what I thought.

You're not the first on 'that one'. Back a few years, I was VP of the Greater Washington Section of the MBCA. I wrote a monthly article in our newsletter, entitled Gute Fahrt. A section member complained because he was offended by the title.



Have a Good Drive!