I just scored....

[Charlie_R]

... a Pac Fab Dynamo 3/4 hp pump and a smaller Hayward sand filter.

Doing some freelance work for someone, and trying to teach him a bit about the TFP method of pool care. He's wanting to get rid of items that he'll never use again, and this set was among the stuff going to the trash.

Motor bearing at the wet end is gone, caused by the shaft seal leaking. I haven't looked into it yet, but I'm thinking a bearing and seal kit is all I'll need, and a lot of careful disassembly. The only thing I've done so far is applied power. The shaft is seized, so possibly an impeller for it as well, if I can't get that off without breaking it. Model # DYNII-N1-3/4.

Will most of the go-kits for Pentair/Pac Fab Dynamo pumps work for this?

The filter multiport valve sticker is a bit faded, but I can get most of the model number from it -- SP ?711 ?I3. Question marks denote unreadable digits. Rated for 75 psi, and 75 gpm.

The filter body has these numbers still barely readable: GM 142K1575, and 300G14.

Not having done anything with a sand filter before, I took a pic of what looks to me to be mason's sand in the filter.

Here's some pics of the goods:











Yes, that is a lawn mower body that I have the filter sitting on, just to move it around the yard.



This sand doesn't look right to me, but I don't know what it is supposed to look like.

Any help would be appreciated.

 

[zea3]

The filter sand should be 20 silica sand. Since you are not sure what you have it is no big deal to replace the sand, and it gives you a chance to make sure the laterals have not been damaged.

 

[Charlie_R]

Had the time to take the pump apart today.

It was immediately obvious that the seal had been leaking a very long time. Long enough for the shaft to rust enough to crack the impeller, behind the threads, in the hollow area that fits over the motor shaft.

For some strange reason, the bearings have survived this treatment. Reassembled the motor minus the wet end and it runs like a champ! Bearings run smooth, no roughness or bearing noise.

Reassembles the wet end onto the motor with the old seal and partially broken impeller. Hooked it up to the pool with 1-1/4" hoses, and plugged it in. Now THAT'S some water flow!

Found the go-kit for it, and have at least that on order. I'll be ordering the impeller tomorrow, after a trip to the bank.

Next up will be getting the sand filter ready for installation. I'll see if I like it. If this works out, I know who will get a pump and filter unit for their Intex pool, with the modified filter canisters.

Does the #20 silica filter sand look like a fine white sand, with all particles looking roughly the same size?

 

[Charlie_R]

Does anoyone have any idea how much sand is supposed to be in this model filter?

 

[zea3]

According to the owner's manual it holds 50 pounds of sand.

#20 Silica sand is coarse and looks like this

 

[Charlie_R]

Thank you for finding those, Zea!

From the pics of that sand, I may have the correct sand in there.

The OM helps out immensely, I had been looking for that, with no luck.

I will have to purchase a new band clamp, or figure a way to repair the one that is on it.

I look at it this way: The set didn't cost me anything, so even with repairs, I'm $$ ahead.

 

[zea3]

You're welcome! Good luck with the repairs!

 

[Charlie_R]

Parts for the pump are ordered and shipped as of today.

The only thing I've found wrong with the filter is the band clamp needed reworking. A couple of hose clamps, a little welding, and that's fixed. I find evidence on the outside of leaking at the joint between the multiport and body, I think it's safe to assume it was never installed properly when the sand was replaced. Former owner was "pool stored".

What I've learned for this type of band clamp is that you tighten it snug, tap all around the clamp with a rubber faced mallot (16 oz deadblow works quite well) to seat the clamp, then snug it again. Rinse and repeat a few times until you get no movement of the clamp. These are used on many types of heavy equipment, and some aircraft engines. Very secure attachment system, when done properly.

 

[Charlie_R]

Well, got the parts today, it took me about a half hour to fix the pump.

Plumbed it into the system, through my cart tower. With only 30 sq ft of filter area, I'm back to having a blowthrough problem. That pump is just to much for that small of filter area. I'll put the sand filter in, and see if I like it. I'll still complete the second tower, just as an experiment to see how well 60 sq ft would do with the more powerful flow.

 

[Charlie_R]

A quick update:

The sand filter I was given does have a hairline crack near the top. I think due to UV degradation. It leaks a little, and I'm not sure how long it will last like that.

Now that I've gotten used to the differences between sand and cart filters, I will be replacing this one, probably with a Hayward S144T.