ammeter repair and upgrade

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My wife and I were sitting and talking about why the ammeters that were always "blowing" when there was a higher amp alternator put on the system. This happened through the years when her father was alive. Looking through e-bay I found an ammeter that was 40 amp and wondered if this could have been the problem. If so how could you fix it to handle up to 112 or so amps? Is there someone out there that knows a work around or someone to do an "up grade" to an existing ammeter? Being we're going to put the radio set up back into the car it will require the power from a heavier duty alternator. I think the alternator of the 69 Fury series was only 40 amps to begin with. Any help is appreciated. All ideas welcome.
 
You can run a second wire the same size as the first from the alternator output to the big lug on the starter relay. This cuts to load on the ammeter in half and will help to keep it from getting fried. Be sure to add a fusible link to the new circuit. Toasted ammeters was a common cause of dash fires on police cruisers that had the high output alternators and A/C. The are several posts on this site by Big_John about this type of upgrade. (See Battery Cable Questions post by Big_John)

Dave
 
maybe that is why there is so many wires running from the starter relay. This is going to be a fun mess to figure out where it all goes. by the way can any one tell me what the black box b is on the radiator core. Measures about 4 x 6 inches or so(eyeballing). Any police enthusiasts out there?

wiring 2.jpg
wiring 3.jpg
wiring 1.jpg
 
Black box looks like and old school Delco voltage regulator. Does not belong on a Mopar, but it was probably a service modification at some point. Also has a Mopar mechanical regulator on the firewall. I would guess maybe the harness to the Mopar unit gave up and somebody tacked on the Delco unit, or they used the Delco regulator to be compatible with a high output Delco alternator. The other choice is that some cruisers had a relay mounted on the core support to energize the siren, most of them just used a ford starter relay with the mechanical siren, the wiring to the black box is not heavy enough to power an old school siren, so it doubt it is a relay. What year cruiser is this, looks to be about a '68 or '69.

Dave
 
ammeter and oil guage 4.jpg
Black box looks like and old school Delco voltage regulator. Does not belong on a Mopar, but it was probably a service modification at some point. Also has a Mopar mechanical regulator on the firewall. I would guess maybe the harness to the Mopar unit gave up and somebody tacked on the Delco unit, or they used the Delco regulator to be compatible with a high output Delco alternator. The other choice is that some cruisers had a relay mounted on the core support to energize the siren, most of them just used a ford starter relay with the mechanical siren, the wiring to the black box is not heavy enough to power an old school siren, so it doubt it is a relay. What year cruiser is this, looks to be about a '68 or '69.

Dave
It is a 1969 Plymouth Fury VIP used by the New Mexico Mounted Patrol Commander as his personal cruiser. I found out that he installed the radios on all the troopers cruisers. Thank you for the information. This is just a small part of figuring out CB Savage's quirks.
 
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do yourself a favour and bypass the ampmeter and install an aftermarket voltmeter.
There is one already installed inside along with a mechanical oil pressure gauge. Looking to change both gauges especially the oil pressure gauge (going electric). Don't like hot oil when the line breaks.
 
It is a 1969 Plymouth Fury VIP used by the New Mexico Mounted Patrol Commander as his personal cruiser. I found out that he installed the radios on all the troopers cruisers. Thank you for the information. This is just a small part of figuring out CB Savage's quirks.

That harness is a real mess, some of the heavy gauge wiring is for the Motorola Radio, many of those used to draw 50+ amps on transmit, also suprised to see drum brakes.

Dave
 
That harness is a real mess, some of the heavy gauge wiring is for the Motorola Radio, many of those used to draw 50+ amps on transmit, also suprised to see drum brakes.

Dave
I know the wiring is a mess, going to need someones help to dope it out. The front brakes are disc, the rear are drum . Didn't help any when the guy that bought the car from the original owner took out the engine ,trans,radiator, and drive train and put them in a race car. I forgot to mention he had 2 antennas for UHF/VHF (ham) and CB set up as well as the police radio and scanner. Don't know what all the second guy removed from under the hood or the wires he cut. As to the last part of your post when we get through it will have 4 wheel disc brake. Much safer
 
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I know the wiring is a mess, going to need someones help to dope it out. The front brakes are disc, the rear are drum . Didn't help any when the guy that bought the car from the original owner took out the engine ,trans,radiator, and drive train and put them in a race car. I forgot to mention he had 2 antennas for UHF/VHF (ham) and CB set up as well as the police radio and scanner. Don't know what all the second guy removed from under the hood or the wires he cut. As to the last part of your post when we get through it will have 4 wheel disc brake. Much safer

It has what looks like a drum brake booster and drum master on it now, so you will need to find a new booster. The correct unit would be a Bendix dual diaphragm booster. If you are going to put it back together as a performance build, discs on the rear might be nice to have, if it is going to be a stock restoration, the front disc and rear drum brakes are more than adequate.

Dave
 
It has what looks like a drum brake booster and drum master on it now, so you will need to find a new booster. The correct unit would be a Bendix dual diaphragm booster. If you are going to put it back together as a performance build, discs on the rear might be nice to have, if it is going to be a stock restoration, the front disc and rear drum brakes are more than adequate.

Dave
I have a 1970 Chrysler 300 as a parts car. The Booster is a Bendix dual diaphragm booster and is the same for both cars. In fact this dual diaphragm unit was used until at least 1973. I am having to send at least one booster to Cardon for rebuild. Other wise they have been discontinued through 1973 at least. Also found some disc brake cars used the drum master cylinder. It was ordered from the factory with disc brakes.This car turns out to be a "switch over"year car. 1st year for the switch over from 4 piston calipers to single piston caliper. 1st year to have the lower ball joint the same used on drum brakes,instead of the 4 bolt lower ball joints used in 65-68. I guess they found it was cheaper and faster to be able to use some drum parts. This carried from 69 on.
 
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I have found out that this is also the first year they did away with the front and rear windshield gaskets and went to the more modern clips and butyl tape of the time. Now they are using a urethane to seal the front and rear glass for our modern cars.
 
I have a 1970 Chrysler 300 as a parts car. The Booster is the same for both cars. I am having to send at least one booster to Cardon for rebuild. Other wise they have been discontinued through 1973 at least. Also found some disc brake cars used the drum master cylinder. It was ordered from the factory with disc brakes.

The factory master cylinder has a larger front section because the discs take a greater fluid volume, the disc piston is a large diameter unit and as it moves out to compensate for pad wear, the fluid fills the void to the rear of the piston. The system volume was calculated so that fluid would not need to be added as the pads wore down. Modern 4 wheel discs use a master cylinder with equally sized front and rear chambers. That type of master cylinder was not used in '69 except on drum brakes. Boosters for the discs were all Bendix dual diaphragm units from '65 to '70. The correct unit for your cruiser is a '68-'70 Bendix unit, The clamp type booster (Midland) was only used on drum brakes and only puts out about 80% of the boost action compared to a Bendix unit. I would not recommend having Cardon't rebuild anything I planned to drive, very poor quality. www.boosterdeweyexchange.com does them to factory specs and will get it right the first time.

Dave
 
The factory master cylinder has a larger front section because the discs take a greater fluid volume, the disc piston is a large diameter unit and as it moves out to compensate for pad wear, the fluid fills the void to the rear of the piston. The system volume was calculated so that fluid would not need to be added as the pads wore down. Modern 4 wheel discs use a master cylinder with equally sized front and rear chambers. That type of master cylinder was not used in '69 except on drum brakes. Boosters for the discs were all Bendix dual diaphragm units from '65 to '70. The correct unit for your cruiser is a '68-'70 Bendix unit, The clamp type booster (Midland) was only used on drum brakes and only puts out about 80% of the boost action compared to a Bendix unit. I would not recommend having Cardon't rebuild anything I planned to drive, very poor quality. www.boosterdeweyexchange.com does them to factory specs and will get it right the first time.

Dave
I thought I remembered a set up like I have and I found it. Page 5-25 (Brakes) in the Plymouth service manual fig-3 power brake booster assembly (Bendix) drum and disc brakes (426 Hemi only). With it having a high perf engine and 140 mph speedometer It needed some serious stopping power. Remember this was set up for the New Mexico Mounted Patrol commander. So it had to be heavy duty and it has a factory trailer hitch which when used had to stop what was behind it. So I can see the use of the 426 Hemi brake set up.
 
I thought I remembered a set up like I have and I found it. Page 5-25 (Brakes) in the Plymouth service manual fig-3 power brake booster assembly (Bendix) drum and disc brakes (426 Hemi only). With it having a high perf engine and 140 mph speedometer It needed some serious stopping power. Remember this was set up for the New Mexico Mounted Patrol commander. So it had to be heavy duty and it has a factory trailer hitch which when used had to stop what was behind it. So I can see the use of the 426 Hemi brake set up.

Remember that the 426 engine was not offered on C-Bodies, they are different boosters. See section 5-100 of the '69 parts manual. B-Body booster is 1" smaller and has a different linkage setup. Correct booster is a C-Body only. Parts book does show a Midland-Ross booster with some disc applications, but this was not used on any police cruiser that I am aware of with 440 engine.

Dave
 
wow, that wiring is a mess. i see buss fuses, lamp cord, bad crimps and wires spliced with electrical tape. delco regulators have 4 prongs on one side, but i've never seen one with fins. you may be better off to remove everything and start over with a good used harness and add the police circuits you need as you go. how is the under dash harness?
 
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