Why did this pump break??

[renoman69]

Went to winterize my fiver last weekend and when I tried to pump the antifreeze through the system I got no action. Took the pump out and took it apart to find this.






The pump worked fine about 3 weeks earlier and we had no frost yet. It is broken on the "dry" side of the pump head too so it can't have been from freezing. Any thoughts?

[renoman69]

reasley wrote:
If you wish to repair the pump, the part you need is 94-238-03. It consists of a wobble plate with the bearing, the plastic housing and diaphragm. The suggest list price is $35.75.

....and 65.00 to ship it to Canada

[reasley]

If you wish to repair the pump, the part you need is 94-238-03. It consists of a wobble plate with the bearing, the plastic housing and diaphragm. The suggest list price is $35.75.

[Old-Biscuit]

mlts22 wrote:
The downside is that it is a C-note or two for a new pump. At least you can get a variable pump or stick in an accumulator tank so it doesn't short-cycle or pulse when you are running the sink very lightly.

You can get a Shurflo 4008 (3 gpm/55psi) for $65

It will cost you twice that to rebuild/new Shurflo 2088

[mlts22]

The downside is that it is a C-note or two for a new pump. At least you can get a variable pump or stick in an accumulator tank so it doesn't short-cycle or pulse when you are running the sink very lightly.

[reasley]

Dog Folks wrote:

renoman69 wrote:
I've already bought a new one but this pump was not "not used" but used sparingly and the type of failure is more than a bit unusual.

I agree. We used the same pump in business and had a lot of them on the road. Never seen a failure like that.

Actually this is not all that unusual a failure. While not as frequent as switch or motor problems, we see a few each year. Usually when there leak between the diaphragm and the motor housing, the motor will seize because there is no seal on the motor shaft. On occasion if just the wobble plate bearing seizes, this type of destruction will occur. We sell several hundred diaphragm pumps each year and have seen just about every possible failure.

[Dog_Folks]

renoman69 wrote:
I've already bought a new one but this pump was not "not used" but used sparingly and the type of failure is more than a bit unusual.

I agree. We used the same pump in business and had a lot of them on the road. Never seen a failure like that.

[renoman69]

The motor runs just fine but there IS some rust there on the bearing which leads me to believe the maybe last year there was water in there and when I winterized the anti freeze did not get in there because the leak was so small and it cracked just enough to weaken it. I did use it this summer and it was fine.

[reasley]

It looks to me like the bearing in the center of the wobble plate seized. If you turn the wobble plate does it turn the motor over?. The plate when detached from the diapgagm, should turn freely without turning the motor. The wobble plate is mounted on the motor shaft at a slight angle. As the motor turns it causes the wobble plate to wobble, which is how the diaphragms move back and forth. If the center bearing seizes, it turns the plate breaking the the support webbing as in your picture.

From the appearance of rust on the the bearing in the photo, it would appear that there was a small leak into the housing behind the diaphragm causing the seizure.

[Al__B]

It definately could be freezing. I had a failure similar to this caused by freezing. The rubber diaphram expands from the ice and voila! Broken pump.

[renoman69]

I've already bought a new one but this pump was not "not used" but used sparingly and the type of failure is more than a bit unusual.

[robsouth]

renoman69 wrote:
Well this pump has been used sparingly. Hooked up to city water more than 90% of the time.

Therein lies your problem most likely. Dry rot from non use. Anything mechanical is subject to break down at any time. Just replace it and move on. JMHO.

[renoman69]

Well this pump has been used sparingly. Hooked up to city water more than 90% of the time.

[dougrainer]

Things break. It is that simple. Do NOT rebuild. It will cost more to rebuild than it is worth. Buy new. Doug

[sch911]

Hard to tell for sure from the photos but, I too agree it appears to be fatigue.