30 AMP fuse blowing - Montana Owners Club

cmawendy · 05-11-2009, 12:37 PM

Whenever we raise our front or back jacks without bottoming them out, it will burn out the 30 amp fuse that runs the slides and the jacks. I've tried to stop short of running them up tight but no matter what I do it will still burn the fuse. Any ideas? Thanks Mark

boylanag · 05-11-2009, 01:19 PM

When raising or lowering, if I quickly change direction without waiting for the motor to stop, it will blow the fuse.

HamRad · 05-11-2009, 01:45 PM

cmawendy,
If it blows every time then it must be binding somewhere or you have a weak or bad electrical connection somewhere along the line. It should not burn out in a normal situation. If under warranty get it in for the fix. If not then trouble shoot yourself or pay someone to do it.

Good luck and let us know what you find out.

HamRad

H. John Kohl · 05-11-2009, 02:24 PM

Quote:

quote:Originally posted by cmawendy

Whenever we raise our front or back jacks without bottoming them out, it will burn out the 30 amp fuse that runs the slides and the jacks. I've tried to stop short of running them up tight but no matter what I do it will still burn the fuse. Any ideas? Thanks Mark

No sure which trailer you have but our slides are hydraulic and the jacks are electric. We have a 50 amp fuse on the bulkhead for the hydraulic pump and a 30 amp fuse for the electric motor that powers the jack.
They are not on the same fuse with our wiring.

Waynem · 05-11-2009, 02:40 PM

As stated, you need to see if there is a problem.
What I did on our 3400RL was put a 30A AGC Circuit Breaker in the place of the 30A fuse. If it tripped, it reset after about 10 or 15 seconds.

It has been mentioned in other posts that a loose ground will cause the current to go up, and some have reported that the ground wire from the jack motor was not a good ground. After fixing the ground, they no longer had the fuse blowing. Check all the wiring to and from the motor, and all ground leads.

Good luck.

cmawendy · 05-11-2009, 03:11 PM

Thanks for the ideas I will check them out when we reach Iowa

cmawendy · 05-11-2009, 03:13 PM

oh and ours is a 2008 3665 RE Montana

stiles watson · 05-11-2009, 03:18 PM

When I first got this unit, the ground was inadequate. I relocated to a more solid ground and stopped blowing fuses. Since then the only time I have popped a fuse is because I forgot to loosen the stabilizers before trying to move the legs. This increased the amperage sufficiently to blow the fuse.

The point is that there is some reason for the elevated amperage, i.e., poor ground or binding, etc.

iowaone · 05-11-2009, 04:35 PM

Dealer switched me to a 40 amp fuse. Not problems since

RickW · 05-11-2009, 06:34 PM

I replaced the 30A fuse with the 30A Thermal Circuit Breaker.

http://www.westmarine.com/webapp/wcs...classNum=14180

Have not blown it since I switched but it is nice to know all I have to do is reset if tripped instead of worrying if I have a 30A mini blade fuse.

grampachet · 05-11-2009, 07:23 PM

CW in Burlington, WA replaced my motor under warranty, said it was bad. I replaced the fuse with the circuit breaker and have no problems now. I now question CW's ability to fix anything. The kitchen faucet was leaking under the handle so they say we will replace it, $96 dollars under warranty. I brought it home and took off the handle and tightened the adjusting nut and no more leaks. Do all they know is to replace??

Glenn and Lorraine · 05-12-2009, 12:09 AM

1st thing to do is re-ground the motor. Even the folks at Lippert, during our visit, relocated the ground wire to a much better location. Their reasoning was a possibility of blowing the fuse.

rames14 · 05-12-2009, 12:46 AM

Glenn -
Do you know where they change the ground to? If possible a picture. I haven't gone looking for problems on the new unit yet, so I don't even know where it's grounded. I have so many electronic do-dads on the new Big Sky that when I power up the lights dim in Milwaukee.

billben1 · 05-13-2009, 05:44 PM

We had the same issue with the front jacks on our 2009 3400rl. Dealer replaced the 30A fuse with 50A self resetting breaker and no problem since. Dealer said that was what Keystone recommended...

Bill

NCFischers · 05-14-2009, 12:58 AM

I lowered the landing gear about 1/4 inch and put a band of black electricians tape around the drivers side leg. When I can't see metal leg above the tape when I'm raising the gear, it's up far enough. Now I don't put a bind on the motor and blow the fuse. I still carry extra fuses just in case.

hookman · 05-14-2009, 01:46 AM

I was told tomove the ground wire to the same place that the battery ground wire id attached to the frame.I also put a 40amp fuse in to replace the 30amp one.

sreigle · 05-22-2009, 09:39 AM

Some Montanas come with a 30 amp fuse and some with a 40, even in the same model. Ours has the 40. We've blown the fuse once. You can either go to a 40 or get an auto reset 30 amp breaker from an auto parts store. The 30 amp breaker has the same blades as the fuse and should fit in the fuse holder. That breaker will reset after maybe 30 seconds if it should pop. Then you're good to go. I'm not sure if that breaker actually fits the holder. If not you might have to get a different holder.

NCFischers · 05-24-2009, 01:58 AM

Being an electrician for more than 40 years, as I've stated in other threads, the 10 gauge wire for the jack motor should be protected with no more than a 30 amp fuse or circuit breaker no matter what the dealer, Keystone or anyone else says. A 40 amp fuse will NOT protect the wire from overheating and can cause a fire. Based on the bigger fuse theory, why don't you put 40 or 50 amp circuit breakers on all your house circuits? They are sized for a reason based on wire capacity and the ratings of the things they are supplying power to. You are just asking for trouble by oversizing fuses.

SlickWillie · 05-24-2009, 02:29 AM

Quote:

quote:Originally posted by NCFischers

Being an electrician for more than 40 years, as I've stated in other threads, the 10 gauge wire for the jack motor should be protected with no more than a 30 amp fuse or circuit breaker no matter what the dealer, Keystone or anyone else says. A 40 amp fuse will NOT protect the wire from overheating and can cause a fire. Based on the bigger fuse theory, why don't you put 40 or 50 amp circuit breakers on all your house circuits? They are sized for a reason based on wire capacity and the ratings of the things they are supplying power to. You are just asking for trouble by oversizing fuses.

Well, I realize you are an electrician, but I'm gonna respectfully disagree with this. I believe that chassis wiring is a little different than our household wiring. From what I understand, 10 gauge wire will handle over 50 amps in this situation. JMHO

dsprik · 05-24-2009, 02:43 AM

My 2007 3400 came with 40 a amp fuse. I understand what you are saying, Jim. Are you saying that Keystone made a mistake when they put 40 amp fuses in some of these units?

I need to pop off my black caps off the top of my legs to check for lube. Many are reporting that one or both of their legs are completely dry and once lubed with gear lube they work much easier. I have a tendency to blow fuses (my tech just blew one last week while working on my Montana). I would never go over the 40 amp fuse that came with the unit.

Also, if you have your front legs on uneven ground, you can put a bind on those legs wich would also blow fuses. I will eventually put in a breaker - probably 40 amp? I will also look to reground that motor (as per a recent topic post) and check for loose screws on the motor.

Just coming out of 3 shoulder surgeries this month has been frustrating as I have to run around and find son-in-laws/nephews to do a lot for this work for me - for a while anyway...

You may also like: