Coast Resorts Open Roads Forum: How many of us are there? Owners of Dodge based RV's?

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Topic: How many of us are there? Owners of Dodge based RV's?

Posted By: Griff in Fairbanks on 03/02/10 12:10pm

ALnCORY wrote:

OK, throw back to an old subject.. ballast resistors. I have read how we should always have an extra one for these old dodges, my question is: where is it located, how do I know it has failed, and when I go to my local NAPA store and ask the 25 yr old behind the counter for one... how can I be sure he will give me the right one for my 1974 with a 360. I think this has been discussed in the past but my search didn't bring up all the answers I was looking for. I replaced my plugs, wires, cap and rotor and it runs smooth and starts easy. Just wondering what I might have missed.
thanks,
A.

Here's what they look like:

[image]

The first two images are the two-wire type and the third is the four-wire type. (Images from "Prettykitty's 'new' motorhome" thread.)

It sounds like the ballast resistor is NOT your problem. Ballast resistors tend to be "all or nothing" devices ... they either work fine or fail completely.

If I recall correctly, the ballast resistor on my 1977 B200 van was located on the driver's side of the firewall under the hood. Class C motorhomes used the same cab as the B-series vans so I'd look there first. (On Class A motorhomes, the ballast resistor could be located under the dash or just about anywhere under the dog house.)

During normal operation (ignition key in the RUN/IGN position), ballast resistors reduce the voltage to the coil which, in turn, reduces the voltage the coil sends to the distributor and spark plugs. This saves wear and tear on the rotor, distributor cap, plug wires, and spark plugs.

The starting circuit (ignition key in the START position) bypasses the ballast resistor to provide more voltage to the coil, yielding a hotter spark to help with starting.

As a result, if the ballast resistor is bad, the engine will start and run as long as the key is held in the start position because the circuit is bypassing the ballast resistor. Then, when the key is released to the run position, the engine promptly dies because the broken ballast resistor is preventing current from getting to the coil.

I have not heard of ballast resistors causing any other problems or symptoms.

1970 Explorer Class A on a 1969 Dodge M300 chassis with 318 cu. in. (split year)
1972 Executive Class A on a Dodge M375 chassis with 413 cu. in.
1973 Explorer Class A on a Dodge RM350 (R4) chassis with 318 engine & tranny from 1970 Explorer Class A

Posted By: Griff in Fairbanks on 03/02/10 12:30pm

DeadeyeLefty wrote:

ALnCORY wrote:

On the vapor lock question,,, was that more of a problem with the 440's or do the 360's have the same tendancy... I haven't run my 360 up any big grades in the summer but plan to this year.

I'm interested in this question myself...I might be getting another '77 in the spring and it's got a 360.
I didn't drive the last one (RIP) enough to find out.

Unless you're experiencing trouble, I wouldn't go looking for problems that might not exist.

You're more likely to experience problems due to bad fuel, partially plugged fuel filter, or dirty carburetor.

My 1977 B200 van, with a 318 engine, was purchased in northern Minnesota, driven for several years in southern Illinois and then for several more years in Alaska. In 7-1/2 years and 180,000+ miles, through 100 degree summer and -40 degree winter temperatures, I never experienced any problems with vapor lock.

I did have to rebuild the carburetor several times due to the seals going bad. I later found out this was because I was adding Heet to the gas at least every other fill-up and the excess Heet was eating up the carburetor seals. (This seems to be a problem with the standard two-barrel Carter BBD carburetors because I've seen other cases, including my 1970 Class A motorhome.)

Posted By: ALnCORY on 03/02/10 01:41pm

Thanks Griff,
That was exactly what I was needing to know. I don't have a problem now but was trying to be more prepared in the future. I will try to locate my resistor and then go find a spare to have on hand in case of a problem on the road. From my reading you all seem to think a spare is a good idea, so I just assumed it is a problem from time to time.
thanks again,
A.

I don't think anyones dying statement ever contained the words "I wish I had spent more time in the office", so lets go somewhere!

Posted By: Griff in Fairbanks on 03/02/10 02:06pm

ALnCORY wrote:

I forgot to mention: If your parts store can't find a listing for your motorhome, ask for parts for the a B300 van in the same year and engine as your motorhome. Most of the engine, drivetrain, and chassis parts are the same as on the Class C motorhomes.

Yes, it's not a big thing but can be a real PITA is you don't have a spare with you. Swapping one out only involves two or four wires and a bolt/screw and is less of a hassle than changing a headlight. If you don't have a spare, it involves a taxi ride or a long walk (and a wait for the parts store to open) if your ballast resistor fails.

Posted By: overdrive75 on 03/02/10 04:57pm

Well I promised a pic of the Dodge' replacement a while ago, well here they are.

Posted By: ALnCORY on 03/03/10 08:14am

very nice looking rig there Overdrive.....

Posted By: overdrive75 on 03/03/10 08:07pm

Thanks, but I do miss the Character of the old dodge.

Posted By: ALnCORY on 03/04/10 09:09am

Thats true, they are pretty funky units.... nothing quite like the old dodge mohomes.... I know that Ford 460 is a gas hog but of all the vehicles I have owned over the last 40 plus years, the mopar vehicles and Ford trucks have been the best. They have always run the longest with the least amount of trouble. I plan on getting a bigger class A one day for more extensive trips but I plan on keeping the old dodge around for short campouts and take the grandkids fishin' etc. Congrats again it looks great.

Posted By: eyeteeth on 03/08/10 05:19am

arrrrrgh....

Well... over the weekend, I went to pick up the RV so I could do some more remodeling this spring before racing season starts. I also plan on replacing the shocks, and I need to fix the choke spring. It's currently out at a friends, and it gets very soupy at his place in the spring. So I went out early in the morning while everything was still frozen.

I had been starting it about once a month, and letting it run for a bit. When I got there, she fired right up. I let it warm up a bit, then got it out of it's place. It had already sunk into the ground a bit. I got it semi stuck at one point, but was able to get it onto the frozen road. At that point I took one quick walk around to make sure everything was up, and nothing was dangling. I hopped into the driver seat, applied the seat belt, put it into drive... and it stalled.

Hasn't fired since.

I'm stumped for the time being.

Posted By: Griff in Fairbanks on 03/08/10 08:27am

eyeteeth wrote:

Step 1 - Are you getting fuel? (Is the carburetor feeding the engine?)

Step 2 - Are you getting spark?

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