68 Cadillac MM Combo (Restore thread)

I checked the battery this morning and it doesnt seem to be holding charge. Charge read 11v which is normally enough to start up, when turn the key it briefly attempts to turn over and the battery goes down to 0, then when I disengage the key it slowly climbs back up near 11.

I seriously hope its not the alternator again, I just replaced that again last month. The previous owner seems to have adapted it use an internally regulated alternator. I have removed the battery to have it tested and hopefully traded in tonight. This has happened before with it suddenly not holding a charge.
 
It is a Super Start Extreme battery from O'Reillys. I took it in yesterday and they were going to charge/test it overnight. Last time this happened was April and they went through this and it still wasnt holding a charge so they replaced it under warranty.

Will only driving the car once a week, in a short distance cause the battery to prematurely fail? Obviously if this has happened to me several times the root cause may not be the battery, could it be driving habits that are causing this failure? Could the battery's water be evaporating while not in use for a week? Or could it simply be that I deep discharged it by having a light on and it was permanently damaged in the process?

It is very handy to have the battery gauge on the pillar from the past owner, because I can watch the alternator charge the battery in realtime. Its one of the only non-original things I might actually keep.
 
Sounds like just bad luck with batteries. If you want to try it disconnect battery when you let it sit. Other possibility is you could be overcharging battery and buckeling the plates. The battery seller should be able to tell you if thats the issue. God luck1
 
That brand name has been know for bad electrical parts. Just saying no real experience with them as they are not in my location. Nothing but over charging or freezing will destroy a new battery. What is the amp out put on the gage after you have had the car running a bit. It should go up to a high amp right after starting the drop back till it just on the Plus side. If you kept a volt meter then it should read at about 13 volts running. You can run a battery down playing with things but it takes time to do so .
 
Well on the night that I started it after charging it it was sitting at 11 before i started it. Once it started up it jumped up to about 13. If I gave it some gas it would go up to almost 15. Once I killed the engine though I watched the gauge slowly go down until it stopped right below 11V.

Did this several time, starting up, idling then shutting off and was the same result each time. Next morning it was dead.

I'm going to revisit oreillys after work tonight and see their test went.
 
Well they said it tested as a good battery. Its holding charge fine now though after being on their charging machine.

Ran the beacon through a few parking lots and my neighborhood and its still full this morning. So its in good shape now. Going to hopefully put that hood stopper on this weekend as well.
 
I would like to see if you disconnect the battery and put a test light between the positive terminal and the battery cable, if the test light illuminates. With everything in the car off, it shouldn't illuminate. If it does, then you have something that is drawing the battery down, and you need to figure out what that is.
 
I made some progress this weekend on various parts of the car. Nothing major but progress nonetheless. I adjusted the hood stoppers to get both sides of the hood properly aligned and until I can attempt some sewing I used some safety pins to keep the zippered headliner up.

Got my fluids all topped for next weekend and took it for a 20 minute or so highway drive. Wednesday I may take off one of the door jamb switches in the coach area and take it to oreillys for a comparison. I would like to start doing those one at a time. I know the passenger coach door has an issue with not fully going off sometimes so thats first on the list. While I am there maybe I can find a test light.

This weekend I am going to a local show "Wings, Wheels and Wishes" a benefit car show for the local Make a Wish foundation. Should be a fun show as the airplanes are flying in during the show. My son has never seen an airplane up close so I think he will enjoy it. Last car show we went to they arranged for the National Guard to land a Blackhawk Helicopter, so that was fun
 
There is nothing new that are the same switches as the ones on the car. Try to clean the ones you have is your best bet. I found out that the evapo rust will do them nicely. Just stand then on end with liquid all most touching the cardboard mount and let it work cleaning the brass connections. The dome lights work by switching the ground. When the door opens the contacts close completing the circuit to ground. That one have to wiggle to get the light to come on just needs cleaned.
 
here is what they look like when they are apart. not a whole lot to one of them.
moving parts are plastic the contacts are brass. the rivets are soft copper and you can pry up the paean and pull them thre the bake-o-lite. this one had eaten the bottom hole threw and the pin could not make contact any more.
 

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Ed.. Can I send you some of mine for restoration? You never cease to amaze me how you take some things apart, fix them, and put them back together. All I seem to be able to do now, is loose parts. Seems that the part gets separated from the car, and refuses to be found, so they can be reunited. Looking for the missing part you find all sorts of other things that you hadn't seen for years, or don't even remember having.
 
5 day weekend just wasnt enough, but then vacations from work are never long enough. I didnt get alot done but I put white lithium grease on all of my door hinges and on the hood hinges. Wrapped a rubber band around the metal piece of the driver side sun visor so it stops falling down. Got my tire pressure done on all tires, and gave the bumpers and hub caps a good wash.

Unfortunately my voltage meter stopped working earlier in the week. Not a huge deal as it wasnt original anyway, but it was a nice convenience. I took it apart and the connections inside are all fine. My guess is where ever its connected to the battery is probably disconnected somewhere, I just havent been able to trace the wires yet. Its definitely not at the top of my priority list though

We went to a car and plane show saturday but it was too hot and humid to really enjoy. I am inclined to not go to anymore shows until it cools down in the fall.
 
I want to entertain a theory here that has been buzzing around my head. Backtracking to my return line problem I had awhile back.

Previous I discovered that when I run a filter with a return line the car runs horrible and bogs under any reasonable load, but if I run without the return line then it runs perfectly fine. This of course has introduced vapor lock.

It has been mentioned that the return line may be clogged. But when discussing this was another car show guy a few months back he raised an interesting point. He said if the return line WAS clogged it would be as if there was no return line since no fuel would be getting through, so he said I should check my fuel pressure.

Since then this has been on my list, but I wanted to see what you all think, does this sound like a feasible cause of bog occuring only with a return line. It makes sense to me that fuel being pumped down an additional line could cause issues if my pressure is low to begin with. If my fuel pressure is low or my pump is gimped somehow does this seem like a feasible scenario?

I am hoping to get this checked soon and find out for sure if my pressure is ok, but ive been theorizing that IF this is the case and I resolve any low pressure then I may be able to switch back to utilizing my return line and in turn reduce my vaporlock, and can work on my AC without fear of making vaporlock worse
 
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When you start having problems go to the last thing you fixed. So in the fuel delivery system. What is the first thing that got done on the car? Send in your original carb, sell that thing they put on to one of your buddys you don't much care for and the car will run right. You start swapping parts to things not designed for that car your tinkering on it all the time. It is passable that that carb takes a higher fuel presser the the origional. Most every one with that swap uses a electric pump. That is why the advice given to you first by a number of people was fix what you got correctly. In the long run it is less expensive and gives you the best drivability.
 
With the nice weather over the weekend I got a few things done. I did take off one of the door jamb switches and it was different. I didnt take it fully apart but I did clean the contacts that the screw fastens to with some WD-40.

Checked my interior bulbs and confirmed they are all GE68, also dismantled the coach lights on the sides to make sure it was the same bulb and it was. Removed the rear dome light housing and got the serial. Found that the dome light is the same as a 58-67 Chevy Impala. Ordered 2 dome light covers for $11.

I also took some WD-40 to the casket rollers as they all took some effort to move. Now they spin really well. I didnt do a whole lot of work, it was mostly small stuff, but it was nice to do it in cool weather.

I have ordered a few LED 2950k bulbs (warm white color) to test and see how they look and work in my rear interior lights, since LED uses so much less power, and dont generate as much heat.

I am not a fan of the bright blue-ish white LED lights, so I had to seek out a vintage colored bulb. 2700k is the ideal spec for vintage applications, but the bulb that interchanges with the GE68 I could only get 2950k, which should be fine.

I will report back how they look and take pictures in case anyone else is interested. My main concern is whether they will give an authentic look or not.

Here is the link to what I'm going to try:
https://www.superbrightleds.com/mor...sEbltGXcbNudWYtkQWsHcZy6vt0nct-BoCH1EQAvD_BwE
 
Most of the warm white are excitable. I put them in most of mine. But you do have to be careful getting them as a lot of the sellers have no idea what they are selling. Those lights ground threw the switch not the base. power goes to the light first threw it then down to the jam switch.
You can do the wd trick on the switches in the car. Hold the trip down spray it in the crack top and bottom the work the switch. What your trying to do is clean the green off the brass so it makes contact.
 
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