Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 05-13-2011, 06:05 PM   #1
Junior Member
Monaco Owners Club
Join Date: May 2011
Posts: 5
Alternator issues

I have a 96 Monaco with a problem I've seen many others with. A flaky Tach with inconsistent voltage. I've installed new brushes and replaced a bad diode and it seemed ok but on a recent trip it raised it's ugly head again. It currently has a Hehr Powerline 190 alternator. I've seen others have replaced their alternator with the Delco Remy 28SI 200 amp. If anyone has done this I'd like to hear about it!

First what did you do about the battery isolator, replace it, with what?
The 28SI has a single sense circuit how do you keep from overcharging the second set of batteries?

I don't know what the pulse signal is on the DR but I'm sure it's not the same as the Powerline, is there an adjustment on the tach for the different pulse output?

Any ideas would be appreciated.

96 Monaco Dynasty 38'
Jeep Liberty - Blue Ox
oldtech is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 05-14-2011, 07:56 AM   #2
Senior Member
wa8yxm's Avatar
Damon Owners Club
Workhorse Chassis Owner
Join Date: Mar 2009
Posts: 23,918
Is the isolator a diode type or a relay type? (Solenoid)

In either case the single sense line is all you need, here is why.

Let us assume the house batteires are low but the chassis battery is near full. In that case the house batteries will get ALL the charging current, don't matter if it's a diode or solenoid type since they have the lower voltage they get it all (Assuming the connections are good and the wire is heavy enough)

Reverse that and the chassis battery would get it all

Once they have both reached the same state of charge.. Then they finish charging at exactly the same state of charge rate.. That is if they team up at say 80 percent, they will each reach 81, 82, 83.....99-100 percent at exactly the same instant.

I might add,, all those things you have heard about "Do not connect different size batteries in parallel" When someone starts yammering about that plug your ears,, You do just that EVERY TIME you start your coach.

Home is where I park it!
wa8yxm is offline   Reply With Quote
Old 05-14-2011, 08:28 AM   #3
Junior Member
Monaco Owners Club
Join Date: May 2011
Posts: 5
Diode type.

Yeah I kind of figured that would happen but I've read so many articles discussing methods to charge house batteries, and I was a little concerned about overcharging. Relay, Smart isolators, dc-dc chargers all have benefits and sound like a better idea... but I think you're right a single sense should be sufficient regardless of the isolator. But I'll still have to make a decision of the isolator, it's a 190 and I'm going to 200 although that might not matter.

I have read something about Delco Remy's not working with diode type of isolators but I can't find that article again. Any knowledge? I know there's some voltage loss in the diodes. Any recommendations of a isolator replacement? Is it true most new MH have relay type of isolators?

My other puzzle is the tach. Has anyone pulled out the tach on a Monaco and know if it has any adjustments for pulse signal?

I appreciate any help.
96 Monaco Dynasty 38'
Jeep Liberty - Blue Ox
oldtech is offline   Reply With Quote
Old 05-14-2011, 09:38 AM   #4
Moderator Emeritus
Mike Canter's Avatar

Join Date: Apr 2008
Location: Freeport, ME
Posts: 4,707
Oldtech, my recomendation is to take your Hehr alternator into a local alternator/starter repair shop and get it tested and rebuilt by experts. Don't complcate matters by swapping out to a Delco. I have this local alternator repair shop in Marietta, Georgia that has been repairing my starters and alternators for 20 years and have never had one fail again. He uses the original parts and is great. You can find a shop like that around you. Call a truck repair place and see who they use.
Mike Canter
"Gunner" USN Retired, Airdale
2004 Monaco Signature 44' Conquest. Detroit 60
Mike Canter is offline   Reply With Quote
Old 05-16-2011, 07:27 AM   #5
Junior Member
Monaco Owners Club
Join Date: May 2011
Posts: 5
The alternator was repaired by someone recommended by a Cummins store locally. It was an old guy that's been doing them for 100 years, he took one look at it and said, ' another old piece of junk.'

I had read many others similar stories as mine, many discussions of Delco 28SI, and that's what he said too. He told me he could get my Hehr going and did, ( he put in the brushes and diode), but said it should be replaced. I should add, he wasn't in the business of selling them.

The Delco is a fraction of the cost and is a newer, more efficient design. The Hehr has only 39,000 miles on it. Not good.

I'm going on a long trip in July and I'm not interested in heading out with a questionable alternator. Besides I like to tinker and this looks like a good opportunity.
96 Monaco Dynasty 38'
Jeep Liberty - Blue Ox
oldtech is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

» Featured Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:37 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.