Merc OD

Good news!

Here is a tip for if you buy a new kickdown switch. I bought one, and it lasted less than a year before I started having issues with the OD not engaging. Took a couple of months to narrow the problem down to the kickdown switch as it was only happening at random, and I also thought: "That switch is new, there is no way it's a problem!".

Well, long story short, I bought a new one and took the old one apart. The factory grease in that one year old switch was stiff and not like grease at all anymore. It was very sticky and when it was still in the car, I could reach down and flick the switch on/off with my finger to make the OD work.

So, I carefully took apart the brand new one, and cleaned it out. That grease was also crap and not very much of it. Put in some fresh dielectric grease and it operated much smoother by hand. Been over a year now, and it still works flawlessly. Even in colder weather which was when I had most of the issues. By colder, I mean not much below room temperature.

I don't remember which website I ordered it from, might have been C&G but I think they are all made in the same factory.

You could probably do the same with a used switch, give it a good grease job.
 
I'll buy 2 and play with one of them. My current switch is split at the bottom, I'm not going to mess with it.

It's been a productive day. Not only does the OD work I replaced the starter wire, checked timing, reset fuel psi to 2.5, adjusted the idle down, verified no vacuum leaks with starting fluid and rebuilt the carb! I also made a new carb mounting gasket 1/4" thick to stop with the heat dissipation and giving me a hard time restarting.

I'm showing 22 on the vacuum gauge, I don't know if that's good or not but that's all I could get out of it setting the idle screws.
 
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Quick update. I have ordered a new kickdown switch, I'm waiting for it to come in along with a couple of other things. I topped off the tank and set out to venture as far away from home as I've been with it today. I ended up in every kind of traffic, she didn't miss a beat. I even took it on the expressway and hit 67 mph, cruised at 66 for a few miles. I'm sure it's me but I don't like spinning that motor that fast even though it didn't give me a single issue. I drove a total of 103 miles today and filled it back up. I got an average of 15 mpg using the OD switch I put in. Thanks for all the help again!
 
Glad to hear of the successful drive.

The factory 1950 Mercury rear axle ratio is 4.27 to 1. Combine that with the overdrive ratio of 0.7 to 1 and the overall ratio is 2.99 revolution of the crankshaft for every revolution of the rear wheels. If you have 28 inch tall tires you are running less than 2400 rpm at 66 miles per hour. Your engine is just fine at that speed. Unless there is a balance problem your engine should be happy to around 2700 rpm, which is about 75 mph with your combination.
 
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