Here we go again yet another Trombetta "Big Boy" failure!

[mchero]

I have just about had it with these P.O.S. Trombetta isolator solenoids.
My 1st class A diesel, a 93 Pace Arrow was not charging the house batteries while driving down the road. Found the Trombetta isolator relay not passing voltage thru to the house batteries. Replaced with same and all was well.
Upgraded to current coach and found the exact same issue, Trombetta isolation solenoid failure. Replaced it and all was back in order.
Tonight i noticed the house batteries at 13.5 and the main batteries at 12.3. Went back to the electrical bay, felt the Trombetta and it was warm telling me the solenoid was energized but yet again, not passing voltage to the chassis batteries!
What's with these solenoids, have to replace them every 4 to 5 years?

Anybody found a replacement? I know the Blue Sea marine solenoids look pretty rock solid but the prices will knock your socks off.

Ideas, suggestions?

[BFL13]

You could choose to by-pass the isolator and always have the house to engine batts in parallel even when engine is off. Or you could have a manual disconnect instead of that isolator. One way would be a fuse in a holder. Pull the fuse as your way to disconnect.

Pros and cons for leaving them in parallel. One pro is if parked for long your solar can keep the engine battery up too without having a separate charger for that.

[mchero]

Yes, 300 amp might be overkill.

[theoldwizard1]

mchero wrote:
Cole Hersee link looks interesting. Continuous duty indeed but how many amps? I'm looking for 300 amp plus.

Why so much ?

If its purpose is to isolate the house batteries from the starting batteries during cranking and when the engine is OFF, it will only be ON when the engine is running and you are trying to charge the house batteries from the engine. I am certain that your engine alternator can not generate anything near 300A !

Personally, I would rather have a DC-DC charger. It will not allow reverse flow of current AND it will properly apply a multi-step charge on your house batteries.

[BarabooBob]

When I had my Toyota based Damon Escaper I went through 3 different isolators from O'Reily's and Napp. I ordered a Cole Hersee and it lasted thee next 6 years/60,000 miles we drove it. Easy replacement. I did install a volt meter to show voltage of coach battery to make sure that I was getting a charge. With the Escaper I replaced the whimpy 12 gauge wire with a 6 gauge wire from the isolator back to the coach battery.

[mchero]

Cole Hersee link looks interesting. Continuous duty indeed but how many amps? I'm looking for 300 amp plus.

Here's one;
https://www.amazon.com/Continuous-Solenoid-Relay-Nickel-Plating-Marine/dp/B072MZHK48/ref=pd_sbs_263_...
But $19.00, Really?
Hmmmm
Max Transient current can be 300A, but Continuous Working Current recommend under 150 Amp/ WARRANTY: Life Long Warranty and Free Return and Full Refund

Yo MEX, you checking this out?

[MDKMDK]

jjrbus wrote:
I just replaced the Isolator on my 94 Toyota RV, I believe it was the original one.

I replaced it with a Cole Hersee from Amazon for about $20, we will see what the next 25 years brings.

https://www.amazon.com/gp/product/B001FQL43U/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1

Cole Hersee is the go to replacement for these things. MB Sprinters have similar problems and most of the owners choose Cole Hersee.

[mchero]

azrving wrote:
Are they rated as continuous duty?

The Trombetta is indeed continuous duty. Contacts get crusty & fail. I guess I could drill out the 4 rivets holding the bottom cover on and clean up the contacts but it would be a short term fix. Done it once before but these failures are getting old. $60 to $70 a pop!

Need to repair/replace if I want the alternator to charge while driving down the road.

[azrving]

Are they rated as continuous duty?

[jjrbus]

I just replaced the Isolator on my 94 Toyota RV, I believe it was the original one.

I replaced it with a Cole Hersee from Amazon for about $20, we will see what the next 25 years brings.

https://www.amazon.com/gp/product/B001FQL43U/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1