Question for Little Giant pump users

Delphinus · #1 07-05-2002, 09:12 PM

I'm running a 4MDQ ... the pressure rated version not the flow rated version.

After a few hours of having it cycle water in my sump, there is a definite electrical smell in the air, and the pump is quite hot to the touch. Hot enough that I can't keep my hand on the motor for more than a second or two.

Is this normal? I don't like this, I don't want to leave this pump unattended at all.

This is a new pump, although, it has been sitting for about two months unused. Should I oil it maybe? (I had oiled it when I first bought it, but I didn't run it for more than a few hours back then. I figured as such I didn't need to oil it right now.)

Canadian Man · #2 07-05-2002, 09:27 PM

Well Tony, you know that my pump does not have this problem but i did oil it quite a bit when i got it used from Alan. What type of oil did you use?

Do you want me to stop by on my way home and give you a hands on opinion?

#3 07-05-2002, 09:30 PM

You might have this one covered already but anyway... is the input restricted at all??? you cannot restrict the inlet in any way, you can choke down the output but not the input...
just incase..

Delphinus · #4 07-05-2002, 09:38 PM

Well ... that is a good question. The inlet DOES go through two 90 degree bends. I asked in here about whether this was advisable; the advice I got was to step up the pipe diameter -- so the 90 degree bends are both 1.5" whereas the sump bulkhead is 1" as is the pump input.

Hmmm. If that is not going to work, I am going to have a real headache on my hands. %$#%$#!!!!! Back the @#$!!! drawing board.

Jon -- yes I think I would like a second opinion. Can't be tonight unfortunately. How is your time on the weekend?

Doug · #5 07-05-2002, 10:00 PM

Tony I have to 3MD pumps. One is fan cooled, so stays cool. The other is like yours, just air cooled. It gets very hot. My Iwaki,s do the same. Thats how they expell the heat. I have a small fan blowing on the pumps to keep them cool. Dont know what everyone else does.

Fudgey has 2 4MD,s running. He would be the guy to ask. There is no smell from mine.

Canadian Man · #6 07-05-2002, 10:18 PM

Tony, I dont think your 90"s are the problem,
I have 1 90 and quite a length of pipe before the pump. But then again i have a 1.5" bulk head in the tank i got from you.
could be it.
yes
now that i think of it the pump may be stressing to try to pull that much through the 1" bulk head.

cut back the output of the pump for a few hours/minutes and see if the slower flow helps with that problem.

Bryan · #7 07-05-2002, 11:45 PM

If the little giant is fanless it will get quite hot to the touch, if not the fan should keep it warm to very warm. I wouldn't worry about it getting so hot it catches on fire. They are all internally protected and will shut off it gets too hot.

stephane · #8 07-06-2002, 02:37 AM

dont worry mine are hot like your for more than 4 years and never fail

Delphinus · #9 07-06-2002, 02:15 PM

This seems a little goofy, but I have both the flow rated version of the 4 and the pressure rated version of the 4. The flow rated has an internal fan, whereas the pressure rated one does not. You'd think it would be the other way around, I would have guessed the pressure rated version is the one who works harder.

So anyways. Yes. We are talking about the non-fan-cooled pump here. So it is normal for it be a hot coal? Like I said, I can -touch- it, so it can't be hugely hot; but the flip side is that I can't touch it for more than a second, it is hot enough that you can't touch it for long without discomfort.

I'm used to using all my pumps submerged, my new tank is my first foray into inlines. It's been a long battle, of trying to get the plumbing "just right" -- been plagued with microbubbles from the get-go.

I mean I guess I could throw a fan to blow air on it, that'll deal with the heat. But the other weird thing is the smell. That's the one that really kind throws me off here.

[ 06 July 2002, 10:24: Message edited by: delphinus ]

ldzielak · #10 07-06-2002, 02:52 PM

Delphinus,
I have the Flow rated version of the 4MDQ with the fan, it runs almost as hot as you decrib with no fan on your, must be much quieter. They do have an over temp protection (on mine I know). So I would not be worried about the heat. But after all my learning about 90 elbows and stuff on my overflows, I would not be suprised if you are starving the input. I have a 2" bulkhead, then 2" 90, then goes down to 1" line for 12" and then the 1" ball valve and union on the inlet. I have contemplated re-doing mine to give more smooth flow. If your using a 1" bulk head, with screens, you have a problem.

Lee