Skip to main content ↑ ↓
Topic: updated batt isolator & alternator replacement (Read 537 times) previous topic - next topic

updated batt isolator & alternator replacement

Good afternoon everyone,
Just finished installing a new batt isolator and alternator. I am seeing voltages as high as 14.3 on my scangauge is that OK?
I don't want to cook anything.

Alternator is a  Leece Neville 14V
Battery isolator is Cole Hersee 48160  160 amp

Here is what I did

disconnected the Neg & Pos engine batteries
disconnected the Neg house batteries
switched all breakers under bed to off
shut off salesman switch (first time I use it)
shut off inverter
shut off charger

I removed and replaced batt isolator. I tried to read the schematic but was unable to identify which cable went to Batt 1 on the isolator & which one went to Batt 2. so I connected them as if the old isolator had the label on top( my old isolator's label had fallen off but i could see some glue marks). DOES IT REALLY MATTER WHICH SIDE OF THE ISOLATOR GETS THE ENGINE BATTS OR HOUSE BATTS?

Once i was done with the isolator i removed and replaced the alternator and the 4 wires connected to it.

reconnected the house NEG
reconnected the POS and Neg to engine batts
turned all breakers back on under bed
turned on salesman switch (2nd time I use it)
turned on inverter
turned on charger

Started coach and watched the gauges. The engine batts were between 13.8 and 14.3 on the dash gauge and scangauge.
My house batts were reading as high as 14.8 on the SmartBMV initially which worried me. never seen them that high. then they went down to 13.6
about 8 min in from starting the coach i turned on the fast idle and ran the coach up to operating temp 180 degrees, about 45 min

I then shut the engine off and reconnected to shore power. Turned on the front air conditioner. i don't know what happened but it seemed like i lost power  when the air conditioner would kick in. i could here the thump of the transfer switch, but not sure if i lost power because it was to quick and then it would come back on and the air conditioner would run. this happened several times. when the air conditioner was not running I  put the thermostat down to 68 to turn on the air conditioner and when it kicked in i did not have the sound of the transfer switch .

i went to check the voltage on the engine batteries






thanks
frank
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: Installed new alternator and battery isolator

Reply #1 –
14.3-14.5 is perfectly acceptable.  It's considered the "bulk" charge rate, the rate that will replenish the electron supply in the battery the fastest up to the 80% level.  My Honda motorcycles, with a crude "racing" system charge at 15.5VDC.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Installed new alternator and battery isolator

Reply #2 –
any pics of your install??
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

updated batt isolator & alternator replacement

Reply #3 –
Good afternoon everyone,
Just finished installing a new batt isolator and alternator. I am seeing voltages as high as 14.3 on my scangauge is that OK?
I don't want to cook anything.

Alternator is a  Leece Neville 14V
Battery isolator is Cole Hersee 48160  160 amp

Here is what I did

disconnected the Neg & Pos engine batteries
disconnected the Neg house batteries
switched all breakers under bed to off
shut off salesman switch (first time I use it)
shut off inverter
shut off charger

I removed and replaced batt isolator. I started to remove the screws from the metal mounting and thought for sure they would all break from being in there for 18 years. i removed the screws from the top and only loosened the ones on the bottom to slide the isolator up and out .
the old isolator was held on with 10 screws, the new one only takes 8 so i had to remove the center screw from the bottom, it broke evenly with the mounting plate so not a big deal.  I tried to read the schematic but was unable to identify which cable went to Batt 1 on the isolator & which one went to Batt 2. so I connected them as if the old isolator had the label on top( my old isolator's label had fallen off but i could see some glue marks). DOES IT REALLY MATTER WHICH SIDE OF THE ISOLATOR GETS THE ENGINE BATTS OR HOUSE BATTS?

Once i was done with the isolator i removed and replaced the alternator and the 4 wires connected to it I used an impact wrench on the pulley nut and a pulley puller to get the pulley off. it was pretty straight forward .

reconnected the house NEG
reconnected the POS and Neg to engine batts
turned all breakers back on under bed
turned on salesman switch (2nd time I use it)
turned on inverter
turned on charger

Started coach and watched the gauges. The engine batts were between 13.8 and 14.3 on the dash gauge and scangauge.
My house batts were reading as high as 14.8 on the SmartBMV initially which worried me. never seen them that high. then they went down to 13.6
about 8 min in from starting the coach i turned on the fast idle and ran the coach up to operating temp 180 degrees, about 45 min

I then shut the engine off and reconnected to shore power. Turned on the front air conditioner. i don't know what happened but it seemed like i lost power  when the air conditioner would kick in. i could here the thump of the transfer switch, but not sure if i lost power because it was to quick and then it would come back on and the air conditioner would run. this happened several times. when the air conditioner was not running I  put the thermostat down to 68 to turn on the air conditioner and when it kicked in i did not have the sound of the transfer switch .

Here are some pics
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: updated batt isolator & alternator replacement

Reply #4 –
I am curious what kind of cost it was for the alternator and where you got it.
I am going to presume you have the m11 450 engine and the alternator would be the same as my 1998 U320
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: updated batt isolator & alternator replacement

Reply #5 –
Might be nice to clean up the cable ends at the solenoid in photo #1. Flat file should do it once they are pulled off with a corrosion inhibitor used afterwards.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: updated batt isolator & alternator replacement

Reply #6 –
Quote from: Lt403 –
DOES IT REALLY MATTER WHICH SIDE OF THE ISOLATOR GETS THE ENGINE BATTS OR HOUSE BATTS?
No, on that isolator I do not think it matters.  A 3-stud isolator is usually "symmetrical" in that the exact same charging voltage is sent from the alternator post out in both directions to the battery posts.  (The charging voltage on both battery posts will be less than the voltage on the alternator post due to loss across the diodes, but it should be the same on both battery posts)

It IS nice to know which battery post is connected to which battery bank.  You can determine this pretty easily by checking the voltage on the isolator posts with a multimeter.  First (with engine OFF) check voltage on both isolator battery posts.  Then turn on the headlights (high beams) and fog lights.  Check the voltage again on both isolator battery posts.  The post feeding the START (chassis) battery bank should indicate a discharge on that bank (lower voltage).

I don't know what's going on with your air conditioner.  The high startup (locked rotor) amp draw of the A/C compressor might be affecting the transfer switch?  Other more knowledgeable Forum members will chime in, I'm sure.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"
 

Re: updated batt isolator & alternator replacement

Reply #7 –
alternator was from Find it parts about $490.00
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH