battery isolator

[travelphotog]

Here's a photo of what I think is the battery isolator in my '87 class c RV. Has anyone seen this type before? It looks to be Ford installed. The house battery is not charging when the engine runs.....any suggestions?

[RJay]

The positive side of the coach battery and the positive side of the chassis battery should be connected on each side of the solenoid. With the engine running and the solenoid closed the voltage on each side should be the same. If the solenoid is open the voltage should be higher on the chassis battery.

[subford]

Yes I had one of those on my class "C".

Should be wired something like this:


/

[darzoom]

Looks kind of standard for a single pole solenoid. They have both single and double at Camping World for about $25 bucks. Mine went out on a road trip while driving through the Eisenhour Tunnel outside Denver. The coach battery had rand down. I pushed the button on the dash for aux power and backfed the coach battery to give it enough to stop the warning buzzer from going off. That will test if the solenoid is bad. It took about 5 mins to replace in the parking lot. You can also get them at any auto parts store. Just take the one with you when you remove it. I have seen as cheap as $5. But, you get what you pay for. Have fun.

[YC1]

First, before throwing the solenoid out. Remove the negative leads from both sets of batteries. Then take the wires off the solenoid and clean them up. Replace the connector on the little red wire becuse it looks like it is corroded. Clean the bolts that hold the black wire to the right of the solenoid. Clean everything shiny and new and replace corroded connectors. Twelve volts will not push through corrosion. Once that is done do the same thing to your batteries even though that is not the issue but you will have the negative terminals off and it is a good time. Clean and shiny in 12 volts is a must.

If it does not work after that. The as mentioned you need a voltmeter to see if the solenoid is being commanded to close and if it is then the voltage on each side should be the same. You should hear that solenoid clunk when it closes.

[texnet]

That also could be the Ford Starter solenoid. Have someone start the engine as you touch the body of teh solenoid. If it clicks when the starter is engaged then it is the starter solenoid. And, yes some isolaters have the same shape as the Ford Starter solenoid but they do not operate the same way.

[RJay]

If your going to replace the solenoid I would suggest you look at the AMETEK 12-132. With the recent complaints of solenoids running hot and failures, replacing them in kind will only lead to more complaints. I don't have any interest in this company I just research them as a suitable replacement.

[subford]

Quote:

Originally Posted by texnet That also could be the Ford Starter solenoid. Have someone start the engine as you touch the body of teh solenoid. If it clicks when the starter is engaged then it is the starter solenoid. And, yes some isolaters have the same shape as the Ford Starter solenoid but they do not operate the same way.

That is not the starter solenoid, the cable on the left is too small.

[Dave78Chief]

RJAY said:

Quote:

If your going to replace the solenoid I would suggest you look at the AMETEK 12-132. With the recent complaints of solenoids running hot and failures, replacing them in kind will only lead to more complaints. I don't have any interest in this company I just research them as a suitable replacement.

There is no 12-132 on that web page so I take it you mean 15-132 for those installations where the solinoid body is not grounded.
For installations where the solinoid body is grounded (like the OP's is), I assume you would want to use 24106. However you could simply ground one of the small coil terminals on 12-132.

The OP's picture looks like it is a Cole Hersee 24022 Intermittant duty 12VDC solinoid rather than a constant duty solinoid.

Dave

[RJay]

Hi Dave,
I guess it's not really clear what solenoid the OP is having a problem. If it's the emergency start solenoid it would be a constant current unit to allow for the coach batteries to be charged from the alternator.

You are correct that the unit I referenced is the 15-132. I referenced that unit because it is a replacement for the Trombetta which is normally used in that application.

I think the OP has to post the numbers off the solenoid and we might be better able to help him.

I don't know if his solenoid is grounded or not, he didn't say. Other than his first post he hasn't responded since.

[YC1]

Zooming in shows the solenoid is grounded through the mounting bolts which are a disaster. All the bolts and wiring are a disaster. The wire on the left is a bit small for a starter but could be but my money is this is the isolator relay. Getting the wires and connections cleaned up will probably have it working. In any case it needs to be cleaned up if a new one is to go in its place.

[travelphotog]

I want to thank eveyone for the info......

[darzoom]

Is it fixed and if so what fixed it?

[travelphotog]

I had cleaned up all the terminals and yes I had gotten it to work, but I have decided to replace the unit anyway with a heavier amperage one, since I have increased the output of the alternator and will be adding another battery or two to the circuit

Thanks for all your help