Things That Go Pop At Night. According to HWH.

[Lug_Nut]

Well I got to visit HWH in Moscow, Iowa. There parking lot is something else. Some gravel but mostly mud. They did have 50 amp power however.
My problem was a ground issue which apparently is quite common on Spartan chassis's. The bolts holding the pump assembly had loosened and in one case left. THey put new bolts which would not loosen and also a #2 ground strap from the frame to the pump assembly. They also replaced my key pad. It was questionable that the key pad was faulty or not, but they replaced it anyway.

Now the "bong, bong" at night that some have experienced, though I have not. According to HWH, or at least the people I spoke to, it is caused by hydraulic fluid expansion due to temerature changes. This is common and should not be a concern.

In my opinion (and I designed hydraulic systems of all types) having any air within the system would increase this occurance due to the easier displaced qualities. I would try to remove all or most air by cycling the jacks, thereby forcing the air back to the tank.

Peter

[Lug_Nut]

Well I got to visit HWH in Moscow, Iowa. There parking lot is something else. Some gravel but mostly mud. They did have 50 amp power however.
My problem was a ground issue which apparently is quite common on Spartan chassis's. The bolts holding the pump assembly had loosened and in one case left. THey put new bolts which would not loosen and also a #2 ground strap from the frame to the pump assembly. They also replaced my key pad. It was questionable that the key pad was faulty or not, but they replaced it anyway.

Now the "bong, bong" at night that some have experienced, though I have not. According to HWH, or at least the people I spoke to, it is caused by hydraulic fluid expansion due to temerature changes. This is common and should not be a concern.

In my opinion (and I designed hydraulic systems of all types) having any air within the system would increase this occurance due to the easier displaced qualities. I would try to remove all or most air by cycling the jacks, thereby forcing the air back to the tank.

Peter

[rebelsbeach]

Peter,thank you for this post although like you I tend to "adhere" to the air in the lines being more of the cause than temperature changes in the fluid.
At least I've "heard" THAT explanation more than the temperature version...