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Old 08-29-2017, 10:44 AM
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Distributor Stuck in Block


I have a stuck distributor on a '68 230 with the M180.949 six cylinder engine. The distributor appears to be stuck in place and will not rotate for me to adjust the engine's timing.

I have, so far, squirted penetrating oil where the cast iron distributor meets the aluminum base, and where the aluminum base meets the block, and let it soak overnight a few times. I have gently tapped the bottom edge of the distributor with a small hammer to try and shock it loose with the penetrating oil. I have also run the engine up to full temperature to warm up the block where it is hot to the touch, and then attempted to move the distributor using the methods described above. All have been unsuccessful so far, and the distributor has refused to budge.

The clamp screw and the bolt on the fine adjuster have been loosened when I try to move the distributor. There is also a third screw on the aluminum base where it mates to the block which I removed.

As for the engine's history: it has low miles since a rebuild about 25 to 30 years ago. The distributor has likely not moved since at least 1994 or 1995. The engine runs well with minimal oil consumption.

I think what is going on is there is some corrosion where the cast iron and aluminum surfaces mate up.

Does anyone have any advice or further options I can pursue without damaging the distributor?
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Old 08-29-2017, 06:51 PM
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Do a search of the vintage section, there was a post similar to yours.

Don't tap too hard on the distributor, the housing can crack.
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Old 08-29-2017, 07:40 PM
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You are trying the right things, continued patience along with penetrating oil when the engine is hot is a good procedure. Could also try getting the engine hot and cooling the distributor with ice...expand the block while contracting the distributor then add penetrating oil.

Can you put channel locks with the teeth wrapped in tape and gently turn the distributor ONLY at the base?

The timing can also be set by sacrificing some dwell angle/point gap.

Good luck!!!
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Old 08-30-2017, 06:07 PM
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Maybe alternate with something cold? If you hold canned air upside down and squeeze, the stuff that comes out will freeze stuff. Maybe you can shrink the metal on the dist. enough. - just throwing that out there for consideration.
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Old 08-31-2017, 04:31 PM
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Generally speaking hitting rusty things with the impact or an air chisel is a big help. I've only ever encountered stuck distributors on cheap to replace domestic stuff and I have broken some. Be careful not to crank on it. What I would probably do is run an impact on the retainer bolt or one near the distributor while trying to gently work it back and forth with channel locks.
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Old 08-31-2017, 08:27 PM
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That might be a good idea. It's been a few days, and that cranky old distributor still won't budge. I'm thinking that I may start looking for an extra distributor to have on hand in case I end up having to resort to more "violent" tactics.

As an interim solution, I was able to adjust the point gap to where I could get the engine to idle OK so I can putter around without any difficulty. That came in handy as I needed the 230 Fintail's large trunk to remove stuff from a storage unit today.
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Old 09-19-2017, 10:23 AM
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Fast forward 20 days of penetrating oil, and the distributor still won't budge. It likely has not moved in 25 years or more. I have decided to order a replacement unit on E-bay, which I will have rebuilt by a distributor shop. When that is finished, I am going to do whatever it takes to get the pre-existing distributor out, even if it needs to be broken.

The picture below is of the replacement distributor core that I ordered. It is coming with its aluminum mounting bracket.

I suspect that there is (in the pre-existing distributor in my car) galvanic corrosion between the cast iron distributor case and the aluminum mounting bracket. I think that if I can remove/destroy the aluminum mounting bracket, the pre-existing distributor will come out.

When it comes time to replace the distributor, I will also check the grounding strap on the engine, and clean/replace it and/or its connections if necessary to prevent any electrical aiding of future galvanic corrosion.

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