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Topic: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation (Read 2154 times) previous topic - next topic

Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Replacing the Leece-Neville Alternator with a Delco Remy 40si Brushless Alternator and the Diode Isolator with a Sterling ProSpliR Zero Voltage Drop Isolator

My OEM Leece-Neville 160 amp alternator has not been performing as it should for some time. My batteries just weren't getting charged up enough as we drove.  I had the alternator tested and it seemed OK but it never really did the job.  So I decided to replace the isolator with a Sterling ProSplitR Zero Voltage Drop Smart Isolator and found a Delco Remy 40si 240 amp brushless alternator to replace the Leece-Neville.

Sterling ProSplitR
The Sterling ProSplitR fits right where the OEM diode isolator was (inside the bed box on the end wall). The one I got can charge three sets of batteries and has an input rating of 250 amps. The battery connections are exactly as you would expect. Alternator In, Batteries Out.

Foretravel has an Excite wire (E6) and a Voltage Sense wire (E59) that connected to the Leece-Neville. It took some thinking, a lot of help and encouragement from Peter Fleming, some help from Alan out at Bay Marine and an email to Sterling in England to make sure we had the connections right.

The sense post on the ProSplitR (PSR) connects to the sense post on the Delco alternator.  The ignition post on the PSR connects to the FT excite wire.  The Alt In post on the PSR connects to the B+ post on the alternator. There are posts on the PSR for the Start batteries, Battery 2 and Battery 3. Battery 2 and the Start battery cables go to either side of the boost solenoid. This solenoid is where your Boost Switch connects the House (Battery 2) and Start batteries together.  Battery 3 is linked to Battery 2 now until I add the third set of batteries.

Important!
Depending on the isolator you are using and the alternator you are installing the exact and proper use of these wires needs to be done with care. If you are not sure, ask.  I was pretty sure and was not correct.  None of this is hard but you can do it wrong.

These are available at Bay Marine Supply.
Sterling ProSplit-R – Zero Voltage Drop Battery Isolator
http://www.sterling-power-usa.com/ProSplit-RZeroVoltDropMarineBatteryIsolator-5.aspx

Delco Remy 40si 240 Amp Brushless Alternator
The Delco Remy 40si 240 amp brushless alternator (pn 8600390) has the J180 long hinge mount just like the Leece-Neville. It is almost exactly the same size but weighs a pound or two less.  It mounts where the Leece-Neville was.  The specs say that it is more efficient than the Leece-Neville and uses less engine HP to generate power.

http://www.delcoremy.com/Documents/Brochures/40SI-Brochure.aspx?ext=.pdf

Installing the Alternator
Disconnect the ground cables from all of your batteries. Remove the B+ alternator cable from the isolator. Disconnect the sense and excite wires from the Leece-Neville and put electrical tape over the wire ends. It is good to be careful.  Remove the ground and B+ cable from the Leece-Neville.

At the half way point on the belt between the alternator pulley and the engine pulley pull the belt up to see how much it moves.  Mine moved about 3/8".  This gives you an idea of how much to tighten the belt when you reassemble things. You can also make a mark on the upper adjustable bracket before you begin removing the alternator.

Loosen the locking bolt on the upper adjustable bracket that holds the upper arm of the alternator. Loosen the bolt at the base of the adjustable bracket.  Loosen the through bolt at the bottom of the alternator mount. Turn the adjusting bolt until the belt can be removed.  Mark the belt so that you can reinstall it later with it running in the same direction. I have no idea if this makes any difference it just seemed to be a good idea. Remove the belt. Remove the locking bolt from the alternator where it goes through the adjusting arm.  Move the top adjusting arm up and out of the way.  Remove the nut from the through bolt in the mount base and pull the through bolt out.  The alternator will just sit there until you lift it up and out of the way. It weighs almost 40 lbs so be ready.  Make grunting noises like tennis players do.  It must help with something.

The existing 10' alternator to isolator cable on the Cummins ISM 11 is undersized for a 240 amp current.  You need a fine stranded 105°C rated size 3/0 welding cable to meet the cross sectional area requirements.  I found a spool of 4/0 cable in a damaged box at Amazon for quite a bit less than the same length of 3/0 cable in an undamaged box.  So I used 4/0 cable.  The lugs are a bit more but in the end the cables I made with 4/0 cost less than if I had made them with 3/0 cable. The existing cables from the isolator to either side of the boost solenoid are #2.  These should be bigger for the 240 amp loads. I am using 3/0 cable, the same size used after  the boost solenoid. I am going to use some of the rest of the 4/0 cable to go from the start batteries to the starter.

To remove the existing undersized alternator to isolator cable, raise the coach all the way up and put in your safety blocks. Lower the coach so that it rests securely on the blocks.  I started from the alternator end and cut as many cable ties as needed to pull the cable out of the bundle of other wires and heater hoses, out through a couple of metal hangers and out of a final metal shield where the cable went up to the isolator.  I expected it to take all afternoon but it only took about 15 minutes plus a shower.  The cable was 9'-8" long.  The only way to know for sure is to remove it.  I made the 4/0 replacement cable longer for some installation flexibility.

I also made a new ground cable. It connects to the top of the Delco case so I added a few inches there as well.

You can feed the new alternator to isolator cable down behind the location of the new alternator leaving enough sticking up to connect to the B+ terminal.  You want enough so that when it is all connected there is some left for flexibility. Put in one or two cable ties to hold it in place.

The pulley from the Leece-Neville gets used on the Delco. The shaft is the same size. The nut came off with some persuasion from my impact wrench. I cleaned up the pulley and put a fresh coat of paint on it, slipped it onto the shaft of the Delco and tightened the nut with a wrench.  The shaft has a hex socket in the end so a big allen wrench helps.  They give a torque setting but I don't have a torque wrench of that style so I marked where the nut was on the shaft and used the impact wrench to give it a 1/4 turn.

The Delco Remy alternator goes back in where the Leece-Neville was. Be sure you connect the end of the ground cable to the engine block in place of the old cable. The old ground cable went down and looped back up to the back of the Leece-Neville. The new cable comes straight up and loops behind the Delco to the ground attachment point on top. Get the alternator in place (remember grunting helps), insert the through bold in the base and start the nut on the through bolt. Fit the belt over the pulleys.  Reassemble the locking bolt through the hole on the top bracket of the Delco, through the slot in the adjustable arm and into the adjusting fixture. This bolt can be snugged up so that the fixture is not sloppy but loose enough so that it will still move as you tighten the adjusting bolt. Set the belt tension to what it was before as best you can. They make belt tension measuring gauges. I don't have one.

Connect the B+ and ground wires to the Delco. If you have some anti-corrosion electrical grease this is a good place for that. Use the left over corrugated cable protectors any where chaffing might occur.

The two Foretravel wires you disconnected from the Leece-Neville, the Excite wire and a Voltage Sense wire, are next.  The Voltage Sense wire (white, labeled E59) is not used with the Delco and Sterling configuration. I covered the end with adhesive lined double wall heat shrink tubing and heated it up until it was a snug fit.  While the tube was still hot I pinched the end sticking past the ring terminal with a pliers to seal it up. The Excite wire (white, labeled E6) is powered when the ignition is on.  That is what the Sterling needs to connect to the PSR Ignition post.  A wire must also go from the PSR Sense post to the Delco S post.  I ran a 14 gauge sheathed duplex cable from the Sterling PSR back to the Delco alternator. One wire connects the Sense posts together.  The other wire connects the PSR Ign post to the FT Excite wire. Be sure all of the loose ends are securely cable tied in place.

Now you have to go under the coach and feed the new alternator to isolator cable back through the cable guides and back up where the isolator is located. and add about thirty new cable ties, one every three inches.  Everywhere this new cable goes by a potential abrasion point it needs to be protected with the corrugated cable cover.  I had to get some at the local NAPA store big enough to fit over the 4/0 cable.  This is actually not too hard to get done. There is plenty of room under the coach to sit up and work comfortably.  The plastic cable shields fit fine except for the last metal guide before the cable goes up to the isolator It is a snug fit and you have to work at fitting the cable and the cable shield through there.  I ended up threading the cable through first and the sliding the shield over the cable and working it into place.  Half an hour to reinstall and another shower.

Back at the Sterling PSR, the B+cable connects to the Alt In post. The Sense wire from the Alternator S post connects to the PSR Sense post.  The other wire connected to the  FT Excite wire goes to PSR Ign post. 

Double check all of your connections, make sure they are tight. Reconnect the ground cables to the batteries.

Some basic checks at this point. You should see about +12.8 volts or more (if your batteries are charged) to ground at the Start Battery Post on the Sterling PSR,  about the same at the PSR Battery 2 post and in this case, about the same at the PSR Battery 3 post.  You should see about +12.8 volts at the PSR Sense post.  You should see no voltage at the PSR Ign post. And you will see about 12.8 volts at the PSR Alt In post.

Back at the Alternator, you should see about +12.8 volts at the S post and at the B+ post as well.  The voltage from the PSR Sense feeds the Delco S post which feeds through to the B+ post.

Start it Up
Now is the time to see if it all works. Susan was in the driver's seat with one of our walkie talkies.  I was at the back end with the other walkie talkie, safety glasses on and fire extinguisher at the ready. She started it up, no sparks, no smoke.  Waited for a few minutes and went to the middle idle speed. I went inside to make some measurements at the Sterling PSR , a safer place to do it..

Results
Voltage coming into the isolator was 14.17 volts. 
Voltage at the Start, Battery 2 and Battery 3 posts was also 14.17 volts.
Voltage at the house battery was 14.15 volts.
Voltage at the start batteries was 13.97 volts 
Amps into the Isolator was just over 50, sorry the picture was terrible 
Amps to the start batteries was 46.2.
  Start batteries had been off the charger for a week or more.
Amps to the House batteries was 4.4 amps. 
  House batteries had been charged by the inverter/charger. 
These current readings changed quickly.

We are going to White Water State Park for a mid week outing week after next.  I will see how it goes.

Another DIY project with lots of help from my friends, especially Peter Fleming.  Thanks.

This is an All Foretravel related post. We all have alternators, isolators and batteries.

Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #1 –
I have one of those alternators.  It is a definite step up from the old LN.
Current coach 1996 U320 40'
Previous coach, 1990 36' U280

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #2 –
I upgraded my coach to a 300 amp Delco 40SI and 300 amp isolator last year.

Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #3 –
Nice write up Roger... ^.^d  Bookmarking for future reference.
Don
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #4 –
NAPA sells a belt tension gauge.  Cheap and essential for ribbed belts.  Cummins lists the tension specs for new and used belts.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #5 –
Excellent write up Roger.  That one is a must for the future.

Speedbird 1
2001 U320 Build #5865
Daihatsu Rocky Toad
VW Touareg
'82 F100 Stepside
Beech' Debonair

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #6 –
Roger,
Excellent write up. I will need to read several times. After I bought my coach last September the alternator failed on the trip home from picking it up. My local diesel shop, who I trust, could not get the voltage high enough from the delco alternator they put in. From Foretravel they learned that the alternator needs to be modified to a higher voltage. They replaced the one they installed with a modified alternator from FT. All resulting voltages were then correct. Both the shop and I were puzzled by there needing to be a higher voltage alternator, as they had never heard of such a thing. But it all works great now. Specialized Auto and Fleet treated me very well on this whole exercise. They did not charge for having to install the alternator twice nor for the things they did to try and determine the cause of the voltage drop. New studs and some wiring at no charge, as they felt they should have called FT before starting. Rare to see that kind of service.
2000, U320 36' with Cummins 450, Toad - 2016 Ford CMax Energi
Previous MHs; 1970 Winnebago, 1973 FMC 2900R, much later a heavily modified 1975 FMC 2900R.

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #7 –
Ken

Can you post the model Delco alternator that was originally  put in, and the model Delco alternator you received from Foretravel?

Some Delco models have the voltage "sense" feature that will raise voltage to account for the isolator voltage drop, and some don't.

Most truck shops are not familiar with a coach dual battery system with an isolator, or the Delco "sense" voltage correction feature.

Thanks
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #8 –
Diode based isolators cause about a 1 volt loss throught them.  To get 14 volts at the battery, the alternator needs to put out a higher voltage.  The Sterling ProSplitR has no voltage drop going through it. 

The Leece-Neville alternators (from the 2000-2001 era) had user adjustable voltage output.  The Delco alternators with a sense post sense the voltage at the battery and increase their output voltage at the alternator to compensate for any losses on the way to the battery.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #9 –
Quote from: prfleming –
Ken

Can you post the model Delco alternator that was originally  put in, and the model Delco alternator you received from Foretravel?

Some Delco models have the voltage "sense" feature that will raise voltage to account for the isolator voltage drop, and some don't.

Most truck shops are not familiar with a coach dual battery system with an isolator, or the Delco "sense" voltage correction feature.

Thanks
Peter, I will call Specialized to see if I can get the information. Roger's comment is a better explanation of why FT wanted us to install an alternator that has a higher voltage output.
2000, U320 36' with Cummins 450, Toad - 2016 Ford CMax Energi
Previous MHs; 1970 Winnebago, 1973 FMC 2900R, much later a heavily modified 1975 FMC 2900R.

Re: Delco 40si 240 Amp Alternator, Sterling ProSplitR Installation

Reply #10 –
I went for a short drive Tuesday.  The new Delco is pretty amazing.  Driving down the highway VMSpc reported start battery voltage at 13.9 volts and stayed steady. They had not been on the charger for a week or more.  Before the swap they would start at 13.4v and drop to 13.0 within a few minutes.  By the end of the day they would be at 12.9.  Coach batteries read more than 13.7v when I stopped. 

Longer drive this weekend, 100+ miles.  A better test.  So far I am pretty pleased with the results.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN