4th alternator installed this week.....

Downeast-SMB

New Member
Joined
Oct 21, 2018
Posts
4
We have 2004 Chevy Express with just under 50,000 miles. We used it camping in the Keys for a month for several years. We gave up when we didn’t feel it was reliable enough to make it there from VT. Our troubles started in Feb 2006 in FL. We had no lights, no microwave, etc. Replaced the isolator and the 50 amp breaker and we were good to go. However 4 months later we were back in VT, came out of a store and the van wouldn’t start. Jumped it, which took a while, and then it died immediately. Had it towed to a garage and the first alternator was installed. By the time we got back home, the battery was so low it wouldn’t start again. Back to the garage and same thing happened again. Installed a new battery and it drained. Made many calls to Sportmobile. They sent a 6 amp breaker. Didn’t do any good. Then they sent another isolator. This goes on and on. The van has been sitting in inside storage now for several years and only used sporadically. We put the 4th alternator in this week. Would like to start using it again, but don’t trust it. Thought about taking it back to Fort Wayne where we bought it, but don’t think it would make it! Help! Any suggestions?
 
Starting battery. Have also replaced house. Haven’t tested recently. Many, many times in past.
 
You need someone to test, isolate, and diagnose... not some 'parts thrower' shop. 3 alternators and a phone diagnosis where a parts counter guy mails you a circuit breaker to make you go away, is ridiculous. Time to take it to the next level, and get that van up and running reliably.



My advice: This is one of those times where you take your van to an independent automotive electrical specialist, with a list of symptoms and previous parts replaced. Look around for a recommended shop, the shop that 'the other shops' take their difficult electrical problem children, to.



Be forewarned: you likely will not get a fixed "We will repair whatever is wrong for this cost" type of estimate... you likely have a not very straightforward electrical problem, give them a 'not to exceed' number and have your phone ready to talk to them while they have it apart.
 
Installed a new battery and it drained.

Very frustrating, but sounds like the alternator is the symptom, not the problem. Alternators create the energy for the battery storage and vehicle use...Maybe the first step is to define where the energy is going out of the batteries. To this end you can DIY or find a shop where they can determine any leakage, and then trace the circuit, usually by pulling fuses. One first checks for leakage inductively at the positive terminal of (house or start) battery. Alternatively one can insert an ammeter/multimeter in line being careful to start with the 10+ amp scale with everything turned off (otherwise you could damage the multimeter or its fuse). Any good electrical shop that does auto work should be able to track a leak. If there is no leak and multiple alternators couldn't improve the situation this sounds like a real mystery...You also might have an intermittent short in the wiring from the alternators/batteries along the frame but that would typically blow a high current fuse. Carefully examining the wiring around the alternator/batteries for chafe might be a good idea. SMB had a bad splice to the alternator where they cut in as part of adding the isolator and house circuit that partially burned thru the insulation at a frame member, causing alternator circuit fuse failure only when driving off road in the boonies....that was frustrating...Tested fine in the shop...After the second experience and fixing fuse links (Ford), did a careful inspection And voila. This scenario did not cause a battery drain, just took out the alternator.
Cheers
 
I'd start by disconnecting the house circuit at the start battery. That will eliminate a large chunk of possible wiring problems. Measure the voltage at the battery at rest, then start the engine, the voltage should rise some amount based on where the battery started voltage wise, and the loads it's seeing. Now turn on the headlights to place a good load on the battery. If the alternator is good, it should RAISE the voltage. If it drops, likely the alternator has a problem. If good, you now need to determine if there is a draw with the engine OFF. As mentioned before, place an amp meter in series between the battery post and the disconnected cable. This will show how much current (if any) is being drained out of the battery. It should be in miliamps, but if it's more, say one amp, start removing the fuses one at a time to see when it drops. Let us know what you find and we can figure the next step.

 
I'd also suggest taking it to a reliable electrical shop. Many automotive shops that work on RV's shouldn't have an issue with an aftermarket build.

I've had a few problems with my 06 Ford. Had a lot of trouble with the Surepower separators and I never did find why I went through so many. Switched to a blue sea 7622 and no issues after that. When the van was brand new I had issues with my starting batteries going bad which led to an alternator failure. I was replacing the starting batteries every year. Switched to AGM starting batteries and they've worked great. I also noticed that the stock alternator could not put out enough to power the van if the aftermarket Starcool air conditioner was running so I installed a higher amp alternator. Sometimes one issue leads to another.


Once you have someone go through the system, I strongly suggest having a good battery monitor installed. Hopefully your inverter/charger also has a display panel. Monitoring the charge rate can help point to problems if they pop up.
 
I had similar issues early on. I’d get things checked out for sure, but also consider replacing your isolator with a separator.
I went with the sure power 100A to replace the original SMB installed isolator that went bad, haven’t had issues with it, also went to AGM batteries. It’s possible your new separator is also not functioning as it should, and your house batteries are drawing your starter down, which was my issue. Lots have gone with a blue sea separator and been very happy.
Having solar to keep things charged also prevents the multiple systems installed from drawing down your batteries.
Is the van sitting for periods of time?
 
Sorry to hear. Good luck tracking down the issue. If you end up deciding to sell the van, let me know. I'm in New Hampshire and might be interested. Thanks, Lee
 
One thing that you could check is that the excite wire for the isolator, should be the "E" terminal. This also the line that they sent you a replacement 6 amp circuit breaker for. May sure the other end of that line is connected to a line that is hot only when in the ignition/run position, you do not want it hot all the time, or when the key is in the accessory position.

Isolator's are not incredibly complex devices, although you have a GM , which prompts the extra excite terminal hookup. They also can be easily bench tested. You should not have to be throwing parts at it.

I would certainly look for a good electrical shop, the problem appears to have been there for a while, unfortunately at this point, not knowing how it was stored, what your house charging process was? ( Only using alternator?) , you will need to get all the batteries tested and start from there.

One of the pro's for a Separator over an isolator, is that the isolator is installed in between the alternator and start battery, issues with that can cause problems to the van electrical. A separator sit's between the start battery and the house battery, if there are any issue's worse case you disconnect the wire from the starter battery, makes things easier to diagnose.

good luck

-greg
 
Thanks very much for all the info. Some of this goes way over our heads but we will print it all out and see what we can figure out. I automically assumed we should go to an RV place, but it sounds like several say just a really good electrical guy.
Does anyone know of a good RV place in New England that has experience working on Sportmobile?
Thanks a lot!
 
Probably going to be hard pressed finding anyone "familiar" with a Sportsmobile on the East Coast - this comes from experience.
In this region, Recommend you try pursue larger & more popular RV locations, the busier they are the better chance you have they have experienced mechanics with years of practical knowledge. You're also better off visiting a couple RV Dealers so they can actually see the vehicle...This makes big difference because they can actually evaluate the project - then choose an outfit that comes across confident over one that leads in with a response along the lines of "I think we can"
 
It will probably be faster to do some basic trouble shooting your self. If you have never done it before, it's pretty simple and in the end you will know your rig better if you have problems in the future. We can tell a lot after a few simple tests.
 
I had a very similar issue with my Chevy Express. Several years ago I had a HD alternator installed,about a week later while going to work I felt the engine load down a little, checked the gauges and the voltmeter was at 1/4 instead of the halfway mark @14v. Took the van back to the shop and they replaced it and said it must have been defective. Was fine for about 3 years. This past fall we planned a trip to Colorado, Wyoming and South Dakota from Florida. When prepping the van for the long journey I basically replaced everything on the front end, water pump, power steering pump, belt, all the pulleys and a Bosch HD alternator and start battery. On the return trip after staying at a campground where we plugged into shore power, so the 2 group 31 AGM house batteries had a full charge for the next day and eliminating a heavy load on the alternator. After starting out before dawn fired the van up and after a minute my light for my BlueSeas ACR came on so the house batteries were connected to the alt. About 4-5 hours into the ride while checking my gauges my voltmeter was on around 10v and dropping fast and the batt light was on. Told the wife we are about to go down and to get on the net and find the nearest shop. She looked it up and there was a Chevy dealership at the exit we just passed. Knowing we only had a few minutes left and we would not make it to the next exit I banged a u turn at a emergency only spot in the guard rail, got off the exit and started down a country road and crossed our fingers trying to make it to town, watching the meter drop I told my wife we are not going to make it after a couple minutes we sputtered to a stop in the middle of nowhere in Missouri. To our luck there was a farmer at a building where we pulled off. He called a tow company and suggested we not use the company that he was going to recommend because they were crooks and get towed to the dealership. The dealership was a three ring circus, when I explaned the ACR, I got the deer in the headlight look from the tech, he went to the Mgr and said he didnt understand what a ACR system was, Went out to the van and it started! The tech checked it and said he couldnt find a problem, I looked at the Mgr and said there is a problem and that the voltmeter was reading low and I want the alternator replaced and he agreed. Next issue, they didnt have the alternator in stock so the sent a driver to ORiley Auto Parts down the street which took about 2 hours! and doubled the price. The first thing I did when the problem developed was disconnect the ACR and the house batteries and checked the 75A fuse from the alt to the ACR and the 75A fuse at the end of the circuit back at the house batteries which were both good, eliminating the house system. The new alternator has been no issue for several trips but it always in the back of my mind and never take my eyes off the voltmeter. Im interested in you post to see if anyone can come up with a explanation of this issue. Any other super long trips I will probably take a backup alternator. When I look back it could have been a lot worse having happened in the backcountry and not on an interstate.
 

Try RV LIFE Pro Free for 7 Days

  • New Ad-Free experience on this RV LIFE Community.
  • Plan the best RV Safe travel with RV LIFE Trip Wizard.
  • Navigate with our RV Safe GPS mobile app.
  • and much more...
Try RV LIFE Pro Today
Back
Top