68 Cadillac MM Combo (Restore thread)

You should of replaced or repaired the weather stripping.

True, I need to check the other side and see how it compares. I'm not entirely sure there is any weatherstripping on this side. I think that calls for a closer look.

I'm also considering repainting the coach floor panels soon with some black rustoleum or something. Already decided im not even going to risk spraypaint, will be brushing for sure. I hear you can spray spraypaint into a bowl and then brush it on and it will somehow not streak or show brush strokes. Although that might need more research.
 
If you are planning on using black, then I strongly recommend Bill Hirsch black miracle paint. It goes on with a brush, dries fast, and it a permanent paint. Don't believe me, then ask Ed, how long it took to wear off of his hands!!:eek:
 
If you are planning on using black, then I strongly recommend Bill Hirsch black miracle paint. It goes on with a brush, dries fast, and it a permanent paint. Don't believe me, then ask Ed, how long it took to wear off of his hands!!:eek:

I will look that up, thanks. I am only thinking of black because that appears to be what they were already, assuming black is original
 
Well this past week I was off work for several days sick, so during that time I decided to drive the hearse around the neighborhood for my semi-weekly maintenance drive. Well to my surprise the battery was dead again. I had thought I solved that problem awhile back by shooting WD-40 in all the door jamb switches a month or more ago, obviously not.

Dropped it off at O'Reillys for a charge per usual. A few hours later I picked it up and connected it back up. First thing I notice is that once again the coach lights are dimly lit with the doors shut. So I again go around, open every door and repeatedly push in the door jamb switches to see if any are stuck. Did all 5 doors, no luck. So for that time I decided it may be best to remove the bulbs while I try to figure this out (later i realized it would have made more sense to remove the fuse). So I removed all 6 bulbs from the coach area and set them aside for safekeeping.

Relieved that this should solve my problem I go on my cruise and park it for the next 3 or 4 days. I go out Saturday afternoon to start it and lo and behold the battery is dead AGAIN. I was puzzled since I had removed all the bulbs already. So I went through my ritual again of charging the battery at O'Reillys. They had a new guy goof up and not actually charge it so they ended up keeping it for most the day. Got it put back in at 7:00PM and decided to leave it connected overnight and see if it was dead Sunday.

Before going in the house for the night I removed the "Dome Light" fuse on the MM panel under the hood.

Sunday morning the battery was not dead so all was well. This morning as I pulled out of my driveway to head to work, as I slowly backed past the hearse I saw the front cabin dome light dimly lit. Since I was already running late this morning I did not get under and pull down the under-dash fusebox, I just yanked that bulb. The floor lights didnt seem to be staying lit.

SO we will see this evening how low the battery got drained. Needless to say Im going to be focusing on investigating this electrical annoyance. Ed had mentioned I may have a switch grounding out. While I am not entirely certain where to start on tracing this I did pick up a voltage tester, so thats a start. I have removed a switch once, but couldnt get it apart at the time, so I did a WD-40 treatment. One way or another I will get this sorted eventually and get my lights back in.
 
the switch works by grounding a hot wire. so if you have something that has cut that hot wire going down to the switch it will turn the lights on. the front ones will come on also with the headlight switch turned all the way right maybe can't remember on the miller if they do. I know superior bypassed this GM function. some of them have a rocker switch by the attendants seat that turns them on also. this one is easily snapped on and is not detected.

as the car was not doing this when you go it think back to things you have taken apart and put back together. the normal problem is a a switch left on,next is a screw that cuts threw the insulation on one of the wires grounding it. but I have seen a sill plate pinch final cut threw also. the other quick check is to see if you twisted one jam switch putting them back in and the wires are making contact behind the switch. but first make sure that all switches are in the off attendant seat and dash master panel

normal problem with that switch is they get corroded and refuse to make contact. not that they refuse to open.
 
the switch works by grounding a hot wire. so if you have something that has cut that hot wire going down to the switch it will turn the lights on. the front ones will come on also with the headlight switch turned all the way right maybe can't remember on the miller if they do. I know superior bypassed this GM function. some of them have a rocker switch by the attendants seat that turns them on also. this one is easily snapped on and is not detected.

as the car was not doing this when you go it think back to things you have taken apart and put back together. the normal problem is a a switch left on,next is a screw that cuts threw the insulation on one of the wires grounding it. but I have seen a sill plate pinch final cut threw also. the other quick check is to see if you twisted one jam switch putting them back in and the wires are making contact behind the switch. but first make sure that all switches are in the off attendant seat and dash master panel

normal problem with that switch is they get corroded and refuse to make contact. not that they refuse to open.

Good information. I will check these things and see what i can turn up
 
Well tonight or possibly tomorrow I'm going to try to take out my booster. I had found a source for a re-manufactured part with Summit and had ordered it but the backorder was pushed back 3 times and is now into November.

Initially my reasoning for not wanting to start out with a rebuild is because I didnt want to leave the vehicle "inoperable" in the event I have a situation where someone complains and I am asked by HOA or city to prove it is movable. This is why I wanted to do a swap, then a rebuild.

But it seems that plan isnt very optimal, so I really just wasted a month waiting around for a backorder.

Cancelled my order today and this week im going to dive in and and take this out. I will probably send it to the place in Portland unless I hear of something local that has favorable results, but thats not likely.
 
the switch works by grounding a hot wire. so if you have something that has cut that hot wire going down to the switch it will turn the lights on. the front ones will come on also with the headlight switch turned all the way right maybe can't remember on the miller if they do. I know superior bypassed this GM function. some of them have a rocker switch by the attendants seat that turns them on also. this one is easily snapped on and is not detected.

as the car was not doing this when you go it think back to things you have taken apart and put back together. the normal problem is a a switch left on,next is a screw that cuts threw the insulation on one of the wires grounding it. but I have seen a sill plate pinch final cut threw also. the other quick check is to see if you twisted one jam switch putting them back in and the wires are making contact behind the switch. but first make sure that all switches are in the off attendant seat and dash master panel

normal problem with that switch is they get corroded and refuse to make contact. not that they refuse to open.

The switches ground the neutral wire, not the positive (hot) wire. All neutral wires are white in color, except if they have been added by the body builder. The problem that he has, I believe, is that one of the bulbs is the wrong bulb.
 
The switches ground the neutral wire, not the positive (hot) wire. All neutral wires are white in color, except if they have been added by the body builder. The problem that he has, I believe, is that one of the bulbs is the wrong bulb.

All of my bulbs are currently GE68 bulbs, however i have not yet checked the glove box bulb or the two underdash bulbs, since those havent seemed to be affected..yet.

Unless you are referring to the LEDs. Those were taken out some time ago. This light issue has happened on and off since I got the car, it just always goes away for awhile and I think I fixed it. This weekend I may try to do some more on figuring out the lights
 
If they are double contact bulbs, which the #68 is, then that is good. The dimly lit bulb indicates that something is grounding through the lighting circuit. The interior bulbs usually use a 15 amp SFE fuse, and that fuse also controls the tail lamps. This is the next place to look, and look for a bulb that might have a burned filament that is laying across one of the filament stalks. I have seen this happen, and create all sorts of havoc trying to find a problem. What does worry me, is why is this happening when the car is parked, because all circuits should be closed. I am wondering if it might have something to do with your alternator, not being correctly wired. If you disconnect the negative battery cable, and hook a test light between the negative battery cable and the negative post on the battery, it shouldn't illuminate. If it does, then that indicates that there is a draw on the system. The only thing that should draw any power, is the clock, if your car is so equipped, and that draw is only intermittent when the clock mechanism points close to wind the clock. This should happen about 2 seconds every 3 or 4 minutes, so I doubt that is the issue. If the test light illuminates, then I suggest that you remove each fuse until you find the circuit that the draw is on. If none of this fuse removal stops the draw, then it is on the engine side of the car. Most likely the alternator or the alternator regulator. I am going to make the assumption that the car doesn't have an under hood light, but if it does, then remove that bulb also. You can also have a grounding issue, where a circuit is searching for a ground through another circuit. I have seen this happen with incorrectly installed aftermarket radios. An example would be, you step on the brake, and the radio starts to play. Does the car have a power antenna, and is it working, or is it broken. If it doesn't work, then disconnect the power lead to it. Isolating circuits is the only way that you will figure this out. Once you know what the circuit is that is causing the draw, then you can start tracing the wires to find where the problem is located.
I only had one electrical problem that I was never able to resolve, but it wasn't for a lack of trying. Usually, I find that it is a poor ground, so I always start by finding all the grounding wires, and clean and tighten them first. If it is in the braking / taillight circuit, I use a test lead to find the housing that has the poor ground, and correct that. Same with parking lights. These are usually the most troublesome circuits, and the easiest to repair, since it is a matter of cleaning and tightening to re-establish good grounding.
The last thing that might be the problem, is the headlamp switch, but usually they are very "black and white", it either works or it doesn't. No grey area usually.
Check out all the above, and then report back. Also, keep in mind, that you will not be the first person to have a defective "new" battery. The battery in my 2016 Ford had a weak cell, that was wreaking havoc with the electronics in the car, giving me all sort of weird messages on the On Board Diagnostics, until the battery was replaced under the warranty.
 
Thanks Paul that is very useful information and im definitely going to try this. Offhand I can say the battery has been replaced before under warranty. I have removed the MM dome fuse, but not the Cadillac dome fuse. Issue persists with the MM fuse out, so i will start by pulling the Cadillac dome fuse, and replace the MM fuse, see if I can still reproduce the dimmed lights, and well keep going from there.

Aftermarket radio was installed by previous owner and it does look rather ghetto so that is entirely possible as well. Although I keep the faceplate detached so it doesnt power on, but it could be a vampiric draw.

Clock is not currently working.

I actually bought a test light after this cropped back up a few weeks ago so I finally have what I need to do these tests. As soon as im able to get out there and tinker I will see what I can turn up.

Thanks again for the information
 
Was reading the power brake unit removal section in the shop manual this morning (page 5-21). I am curious why it calls to remove the steering column lower cover in step 3, because as far as I can tell after removing the cover it doesnt seem like it ever actually has you do any work in the steering column?

Is this just to clear working space or am i missing something?
 
The clevis pin and clip are at the top of the brake pedal assembly. Once you remove the lower dash cover, you can access them. The brake pedal assembly holds the upper part of the steering column up. Once you get into it, you will understand better.
 
Thanks, I worked on this all weekend and ran into several issues. Firstly I twisted my brake line removing the lines from the master cylinder (which i later learned I didnt need to do). Got all the nuts out from under the dash (or so i thought) but still couldnt get the booster to budge. Removed the cotter pin from the pedal holding the push rod on but could only get one side to budge.

After 2 days of this I went back to my photos and realized there is one more nut I may have missed. And 2 of the nuts I removed may not have even been necessary. So tonight I'm going to remove this other nut and see how that goes. A few of those nuts sure are hard to get at though, I crawled in and out of that dash so many times over the weekend I'm really feeling it today.
 
Those 70 dashes were no fun to work under. But just think how much fun your having and how fast you can do it the next time.
 
Those 70 dashes were no fun to work under. But just think how much fun your having and how fast you can do it the next time.

Your right, i did think about that.

Make sure to remove the pin that holds the push rod to the pedal.

I did eventually get that. The cotter pin was installed with the edges facing away from me. I tried for a good while to get around it and bend them back but just could not grab it no matter what. I ended up just mangling the cotter pin, once I get everything squared away I will be getting a new cotter pin for it.
 
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