Pump seal

[Bonaro]

Ok, so as a matter of habit I always run a garden hose into the dredge pump intake and run it for a half hour or so before I head out to go dredge, just to make sure everything is good to go.

Last week as I was preparing to go dredge for a week, I followed my ritual and discovered a blown pump seal was slinging water everywhere....glad I tested it.
I had a spare and it was a good excuse to change the compressor belt so I tore it down and went through everything.

The rubber skirt that connects the ceramic seal face to the brass part had completley tore in half, all the way around. It was like the rubber had deteriorated. This was a very curious failure considering I had replaced this very seal only 3 years prior. I would expect at least decade of run time on something like this.

Any ideas why this rubber failed so quickly?
Is there a way to preserve it during storage?
I was planning on dousing it with WD-40 from the outside but I would like to hear opinions.

[libertydave]

A couple of decades ago a miner I met while dredging on the Klamath told me he always uses WD40 both before and after operating his pump. Seemed like simple insurance as WD40 does not affect the integrity of the rubber seal and it does provide some minor lubrication. Been doing it ever since and have not had a pump seal failure in the last twenty years.

LD

[Hoser John]

WD 40 is a aggressive penetrating oil and the last thing I'd ever put on a rubber/plastic seal of any kind. It is specifically designed for metals. I'd be looking at footvalve screen for holes or keeping it off the bottom and away from excessively dirty grit filled water. Can says it removes grease,tar and adhesives-which hold that seal in place I'll bet. Lotza luck-John

[polekaat]

I read somewhere that the main ingredient in WD-40 was fish oil. This would need to be confirmed but, if so, I wouldn't hesitate to use it on just about anything that I own.

Trevor

[Bonaro]

In a previous life I was a boat mechanic. After every service we would spray the entire engine with WD-40 to prevent rust and corrosion. I don't think WD would damage rubber but that would depend completely on the kind of rubber, I guess.

John, here in Washington we have to run an additional screen on our footvalves with 3/32" openings to prevent fish from being sucked into the terrible vortex. I dont think I sucked any grit.

[Hoser John]

All ingredients listed on the can=chlorinated hydrocarbons. I use the stuff religeously on anything metal and a great chemical to detar your car/ages old grease removal,locks,hinges etc-John

[russau]

years back I used to spray the undersides of my dirt bike to help the removal of mud when out riding. with WD-40 the mud would fall off instead of clinging to the bike. plus it helped when washing off the bike before putting it way. but im getting off topic!

[Hoser John]

3/32 is a decent size but terrible vortex-what them insideous environutz thinking?? BUT particles smaller than than that can still chew up seals if bottom feeding.Dredges suck'm up and make fish food so much insanity now a days-John

[libertydave]

You all may chuckle at this but I knew of one dredge mechanic who always assembled dredge pumps 'wet' using WD40 to protect the seal surfaces. During one urgent job he noticed he was out of WD40 so he used KY Jell and said..."well, it worked".

LD

[russau]

NOPE ! Im NOT going to say it!:) ill bet John grining!!!