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wiring up the instrument cluster 1936 Plymouth

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HELP !  Some months back, I took my instrument cluster out of my 36 Touring Sedan.  All the gauges, illumination lights  and odometer worked but the speedometer  was in op.  I made the decision to see if I could restore the instrument cluster along with the speedo.  


I got another instrument cluster from a Plymouth Owners Club member that had been sitting on his shelf in the garage for some time.  When I took it apart, all kinds of bugs (dead) and their carcasses and residue had to be cleaned out of the case.  I found that the gaskets had shrunk but the facia was in good order.  I carefully cleaned up the face plate, chrome trim bezel, made new gaskets and carefully cleaned the gauges.  I disassembled the speedometer and found that the needle indicator would not move due to congealed grease.  I cleaned all of the old grease out of the head and lubed it up.  The local speedometer shop told me NOT to use white grease as it will harden over time.  I used the moly grease that he recommended.  


Attaching a drill motor with a piece of speedo cable to the speedometer, I 'spun:" the instrument and it worked flawlessly.  I polished the outer chrome bezel, cleaned the glass lens and re assembled the cluster.   I have attached pics below to show the process.  I admire the engineers of the day as this speedometer was built for Chrysler Corp by a supplier that really engineered the instrument with quality. Much as everything else Chrysler Corp. designed.  If you ever had a fear of doing your own clean up and repairs of a speedometer, this unit is "straight forward"  No secret pins or gears that will fall out.  But taking out the instrument panel is necessary.    One caution;  If you have original wiring, be sure not to disturb the wires too much.  The insulation is 80 years old and brittle.  So far, I have not had any issues with the wires as they are somewhat pliant. 


I cleaned up the temperature gauge and carefully moved it out of the way as that is the only gauge that has to be re used, unless you are replacing that unit.  The rest of the gauges I swapped out from my original instrument cluster as they worked fine.  I made new gaskets from manila file material and cork. I got new sheet cork from Bangor Cork and cut the new cork gasket from that.  I cleaned the light blue acetate "diffusers" and re attached them to the outer housing.  The instrument lights shine through them giving a nice "glow" to the instruments.  


This was a lot of trouble to go to to get my speedometer working again but being anal about wanting my Touring Sedan in top operation, it was necessary.


I also want to point out, it is to your advantage to remove the glove box, cigarette ashtrays and any other items that will impede your access to the instrument cluster.  I also removed the front seat and laid a piece of plywood over the seat mounts, laying a moving pad on that.  I removed the clutch, brake pedal,  and accelerator pedal.  If I were a younger man and my body was more limber, I could move around much easier but time has not been too kind to me in doing this kind of work.  I am better at vertical tasks.  :-)   In this job, most of your work will be done on your back with your head resting against the firewall.  When I first got the Plymouth, I took the heater out and restored the unit. As I was getting the cooling system in order, I wanted a heater that would give me heat for our cool days here in San Diego.  That gave me an idea of what I was up against in the limited area you have to work with in the narrow cabin.  Unlike a 40's, 50's or 60's cars, there is a lot less room under the dash.


The windshield wiper hose is another issue.  Moving it up and out of the way, it broke in two pieces.  The hose is hard and needs to be replaced.  That is my next job; getting the windshield wipers operational again.


Now for the issue at hand.  I had labeled all the wires and where they hooked back up to the instrument cluster.  Most of the power is supplied from  the back of the Ammeter.  But what hooks up where is now lost to me  due to the sheet that I drew showing what wire hooked up where.  I have been looking for that dratted sheet for over a week.  It must have been tossed by the cleaning lady who did a nice job in my office.  TOO NICE.  It was accidentally tossed in the clean up.


I went to the Plymouth manual but it doesn't show the color coding of the wires. I guess that you have to trace out the wire to see what it is attached to to know where it goes on the back of the panel.  Before I hook up the wrong wire and "fry" this 80 year old harness, I was hoping that one of you would be able to illuminate this issue with a better publication or ? .  


Some are easy.  The instrument lighting is all the same color and the bulbs/sockets are all replaced back in their respective locations to illuminate the cluster. Before I have to take the car to my friend who has an auto electric shop, I would like to try to solve this issue on my own.  At worse case, he is a whiz and can discern how to re attach all the wires in their correct location.


Also, I recently found a "Firestone" radio, which is period for this car.  It is made by Stewart Warner.  I took it to the Antique Radio Shop here in San Diego and the guy, Jeff, is a whiz with old radios.  He replaced all the old capacitors,  and old parts with newer ones.  I found a guy on the east coast who had an original antenna mast (it was EXPENSIVE) new in the box.  The paper work showed that it was made in 1936.  The radio/speaker box mounts on the firewall and the dial with the two knobs and cables mount on the steering column.  With the replacement instrument cluster, there was the correct connection and resistor on the unit.  Seems that the car that this came out of had a radio in it.  What a find!  Solved two problems.  


I realize that this is a long post but I thought that the members who have the 36 models would be interested in seeing what can be accomplished if you take your time and are careful.  It is not rocket science (like the new cars of today) and is enjoyable solving problems that are comparatively easy next to a new car.  


If you have ever done the instrument panel, hopefully, you can shed some light on the issue I am facing here.  Or if you have a 36, possibly you could take a picture of the back of your instrument panel showing the wires and where they go.  That would be monumental in solving my dilemma.  Any help will be deeply appreciated.  






































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In the pictures here of the speedo, it shows the "white grease" in the gears.  After talking to the speedometer shop here in  San Diego, I removed the white grease and replaced it with the moly grease.  As he stated, white grease with harden over time.



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Am I understanding this correctly? Are you retaining the original wiring in the car? I suggest that you go to Rhode Island Wiring in order to get a new harness, otherwise you are inviting trouble ahead. Just a matter of opinion, but I have had my own issues with the wiring that was left in my car when I bought it. I have since replaced it all.

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Nice work Randy. I will be reinstalling the gauges in my '38 Plymouth in the next couple of weeks. My harness looked a little "iffy" so I bought a complete new harness. Got lucky, shopped eBay until one popped up on there for half price.

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Keiser 31,


I would have replaced the harness except for one thing.  It is in excellent shape and has not been disturbed previously.  I am familiar with individuals who have not respected the "old wiring" and in hast to get their cars running, have used compromised wiring harnesses, ending up with a  fire and a melted mass of electrical components and a "fused" bunch of wires.  Believe me, I would not want to be in the latter category.  My harness is intact with the braiding all in place.  Granted, if you move the harness around, you will break the insulation on the wires as I am sure that the insulation is very brittle.  After all, it is 81 years old.  The car ran beautifully with all gauges, lights and instruments all working.  The wires on the back side of the panel are still pliant and believe me, I am extremely careful not to bend or move them any more than necessary.


I got my Plymouth shop book and there is a very good schematic of all the wiring and the destination points of where the wires go.  My problem is that the "color coding" on the wire is rather faded and it is hard to tell the color.  What is simple about the P1 is that most of the power is derived from the hot side of the Ammeter.  I just have to find out which wire is going to the fuel gauge and the ammeter. The oil and temp gauge are mechanical and do not have electrical connections. shouldn't be that complicated to figure out what goes where.  I have made it easy by removing the front seat, the pedals from the clutch and brake and the glove box and ash trays.  I have clear access so I will at least get the car running tonight.  I will worry about any thing that I cannot figure out tomorrow.  



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Well, to all that had been following my dilemma with my P 2, I bit the dust and ordered a complete wiring harness from Rhode Island Wiring and Cable.  It arrived yesterday, the 4th of October and I will have it installed in my Touring Sedan by next week.  I had the shop manual for the wiring, however, the original wire is 80 years old.  The insulation on the wiring is crumbling and it is not a prudent move to keep the original wire.  Plus, the colors are so faded that it is nigh on impossible to tell red from ?  The new Rhode Island wire harness is so well done.  The new wire has the modern vinyl composition wire on the inside and the woven material on the outside.  They make the harnesses to factory spec and the wires will last an eternity without compromise.  Longer that I will last.


The Plymouth is pretty straight forward, however, the engineer that came up with the brainy idea of the shove in headlamp lens needed  to be hung from his toes.  I have dropped two of them so far.  I am down to my last spare and believe me.  If a headlight bulb burns out, it may just stay out.  What a hassle to get that lens to go in right.  Very tedious if you do not do them every day.


I will be cleaning the engine and painting it.  Now that I have the water pump replaced, I want to make the engine compartment look nice.  The firewall is in very good shape and there is no rust on the surrounding sheet metal.  I just want to paint the block, starter, generator, and the air filter.  Now that you can get replacement stickers and decals for the engine components  and compartment, why not spruce up the engine bay?  

My thanks to all that responded to my request for help.  I just thought that I could do with the 80 year old wiring as it "looked: pretty good from the outside. 



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Found your story and pictures here fascinating on your 1936 Plymouth instrument rebuild.  That appears to be about a year ago and I wonder how that project went.  I am sitting on probably the largest shelved collection of MOPAR radios from the 1930s into the early 1949 series.  Also now coming along with quite a large selection of collected dash assemblies for many of those years and applications.  Only comment for now is that your 1936 Plymouth would have had its own radio with the control shaped to fit in place of the left ash tray and with control wires going  down to the power box mounted on the fire wall.  Most would have been installed by the dealer after purchase of the vehicle as an accessory.  My original vehicle that kind of got me started in this radio research collection was with our 1936 Dodge Touring Sedan, not very different from your Plymouth I'd say.  Anyhow, if you can, you might let me know how your Plymouth project is coming along and if there might be any information I might be able to help with.

     Bert   541-350-3056  Redmond (central), Oregon  

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