Ok, well I've gotten to work on it some. Based on what Hoser John said it don't look like it's the seal. I filled the pump with water, and covered the intake hole to see if it was leaking anywhere and it's not leaking.
It does have the big rubber o ring it looks to be in good shape, but a little flattened so I replaced it. I also cleaned the old silicone residue off it, and put some gasket former on the housing before I put it back together.
I'm back to thinking that I was just sucking air somewhere. Either around the housing from it not being put back on properly, or that intake hose. I'm not real thrilled with the intake hose either way, and it's been suspect #1 the whole time. I'm going to try to rig something up with it and go give it a try again here this evening. A few extra hose clamps and some water seal tape should eliminate and chance of that hose leaking air.
I'll post results later tonight.
. I have an older, yellow P180 that I am rebuilding for a 3 inch dredge I am making and I want to put a new seal and bib in it.
If old school pump it used a thick paper seal at the pump-only newer ones used the rubber ring black buna style. On ol'school there was a spacer also on the shaft to keep the impeller in place and many different lengths. If your using(mixing)old/new the O rubber ring does NOT index the outer housing far enough from the impeller hense you run a little-then die as impeller binds up as WAY too close. I could fix in a few minutes with a dial indexing slide micrometer but......put back together,pull starter rope--does the impeller turn?then add water does the seal on the shaft leak water?? if no leaks not the problem. Does the pump outer housing have a hose bib cast into the housing to attach a garden hose to
