How to diagnose Exhaust Riser plugging?

[Ron Hill]

Breaking : If I bought a new pump (any brand) and I installed it and it leaked!!

Guess What !!  I'd call who ever and ship it back to them and get a replacement that didn't leak!! 


A thought

[Breakin Away]

Breaking : To check if there is a blockage in the exhaust water system (from the raw water pump to the HX to the riser to the muffler) 
Just take off the hose from the RW pump and blow into it.  It should be free!!


A thought

I wanted to do that, but the hose did not extend out far enough from the motor for me to get to it, and I didn't have the needed adapters to extend it. I'll try to take together the needed parts to do that next time I go to the boat. I also borrowed a radiator tester from Autozone to do the same thing, but was chased off the boat yesterday by big thunderstorms that came through. Couldn't wait them out because I ran out of time.

[Breakin Away]

Breaking : If I bought a new pump (any brand) and I installed it and it leaked!!

Guess What !!  I'd call who ever and ship it back to them and get a replacement that didn't leak!! 


A thought

I might go one further and just ask for my money back. Not sure he'll do that, but I'll make the argument that since his pump didn't fix it immediately, I used the non-sailing time to disassemble my current pump and am prepared to do a quick rebuild.

I used your instructions to take the water side parts off. When I removed the copper C-clip, it was in great shape. However, the stuff underneath did not spring up at all. I removed all the other components, and the ceramic discs are in great shape. Disc faces are very smooth and shiny - not scored at all. The rubber bushings look good too, after cleaning. The spring and its rubber bushing were dirty, but easily cleaned. The shaft is not scored. Now when I put it all back in, the "springiness" is back.

My guess is that some grime got in under the rubber bushing (under the white ceramic disc) and prevented the spring from being able to push the discs together sufficiently. So more water got in, and then mucked up the spring.

I'm tempted to just put it all back together and see what happens. But at the same time, I might get some rebuild parts for just the water side (based on Ron's suggestion). I may have to get those parts from Hansen since they already have my money - we'll see. Otherwise, I'll be looking for other sources, including you, Ken, if you have them and are willing to sell them.

One question for Ron: Your test says that you didn't rebuild the oil side because it seldom leaks. But your pictures sure look like you bent up the oil side seal and forcibly removed it. Can you explain the discrepancy? [EDIT: I now realize that the part that was bent up and forcibly removed is the bottom of the spring assembly.]

Other suggestions?

[KWKloeber]

A radiator tester is meant to test  that the system is holding pressure, not to gauge how much flow is going thru the circuit. If you have as much as a pinhole Through a blockage in the injection wye, it will let air readily through it and you won't really be able to detect the blockage using a radiator tester because it won't hold pressure.

What you want is to push a large flow (water, air, breath) for a short period. Not hold a vacuum for a long period.

How would you attach a radiator tester to the RWP circuit?

If you're getting good flow from your RWP, out the transom, then you don't have a (significant) blockage at the wye.

Likewise, if you're not overheating then you're getting decent flow through the HX which means flow through the injection wye, which means you don't have a blockage.

On the B-series, it's a harder to troubleshoot the RWP than it is on the M-25/XP/XPA/XPA(C), M-35/A (et al). There's a just not good access to the hose on the business end.

If you pinch the RWP to Hx hose closed, or remove at the Hx and plug it, does the REP weep more? ie, blow past the seal?

If you send yours to Depco they could refurb it overnight (if I asked them nicely.) Another thought.

Or throw an Ob on in less time than you're effin around with yours!  Rebuild it later to hold for a spare.

[Breakin Away]

A radiator tester is meant to test  that the system is holding pressure, not to gauge how much flow is going thru the circuit. If you have as much as a pinhole Through a blockage in the injection wye, it will let air readily through it and you won't really be able to detect the blockage using a radiator tester because it won't hold pressure.

What you want is to push a large flow (water, air, breath) for a short period. Not hold a vacuum for a long period.

How would you attach a radiator tester to the RWP circuit?

If you're getting good flow from your RWP, out the transom, then you don't have a (significant) blockage at the wye.

Likewise, if you're not overheating then you're getting decent flow through the HX which means flow through the injection wye, which means you don't have a blockage.

On the B-series, it's a harder to troubleshoot the RWP than it is on the M-25/XP/XPA/XPA(C), M-35/A (et al). There's a just not good access to the hose on the business end.

If you pinch the RWP to Hx hose closed, or remove at the Hx and plug it, does the REP weep more? ie, blow past the seal?

If you send yours to Depco they could refurb it overnight (if I asked them nicely.) Another thought.

Or throw an Ob on in less time than you're effin around with yours!  Rebuild it later to hold for a spare.

All valid points and good ideas.

My thinking with the radiator tester is that I could fill the outlet hose with water, jam the radiator tester on the end, pressure it up a little, and get a sense for how fast the water was exiting by how fast the pressure drops. (Clearly air would go through a pinhole, but water's viscosity would make it much slower.) I think someone here mentioned doing that with his system. The tester that I borrowed from AutoZone has a couple of conical shaped rubber fittings that expand when twisted, so I could jam them into the hose end and twist to make a seal. I knew it was a long shot, but it cost me nothing, and with the boat 2 hours away I wanted to err on the side of having something extra. Ultimately I didn't get to try it yesterday because I was chased away by a pretty severe lightning storm.

The radiator tester is the same one I borrow every spring to test the freshwater side of my cooling system.

I like Ron's suggestion to just blow through the outlet hose. I'll pull together the necessary fittings to extend the hose out to where I can reach it.

As I've mentioned before, there is absolutely no sign of any blockage anywhere. Everything is working great, except for two leaky water pumps. Temperature always holds steady at 165, and there's plenty of water coming out the exhaust. No noticeable decrease from when I bought the boat two years ago.

Regarding pinching the hoses, are the inlet and/or outlet wire reinforced? I'm interested for a couple reasons, including a plan to cut the inlet and install garden hose fittings for easy belt replacement (and an easy way to winterize).

Rebuilding the Sherwood is super easy (and halfway done already), so that's my first option if I can get parts fast enough and/or re-use the current ones after cleaning them up. If I need a whole new pump the Ob will be a strong candidate.

[Breakin Away]

Question for Ron: When I referred to "forcibly removed" in my prior post, I was referring to these pictures, especially the sheet metal part with the pried up edges that you removed:





Compare those pics to my pump housing. This begs the question, have I removed everything I need to remove yet? Or do I need to pry up the edges of the sheet metal piece in the bottom and pry it out like you did? It seems to be in perfectly fine condition, so I'd be tempted to leave it unless there's something that I'm not seeing. And I'm assuming that this metal piece is the part to which the spring assembly is attached using Permatex. Is that right?

[EDIT: To partaially answer my own question, after re-reading Ron's instructions, it looks like the part I'm asking about is the "bottom of the old spring assembly" which I need to "take the end of a flat tip screwdriver and pry up the edges". I guess my revised question is if I choose to leave this piece in place (since everything looks to be in such pristine shape after cleaning up), what do I use to "re-glue" the spring assembly back into this metal bottom?]

[KWKloeber]

Gotcha on the tester, I didn't know they had those kind of expand-a-plugs.

The outlet is installed by Universal and is **supposed** to be reinforced. THe seawatere us installed by CTY, and must be reinforced, but who knows.......?

I don't know that I'd use GHT fittings on the water line side of the pump but YBYC. Lanacote or SuperLube ptfe gel on the barbs and the hose will come off like butter. I think I mentioned before that those elbows are cast brass not bronze and not recommended for salt water. Just a public service announcement. 🤓

[Ron Hill]

Breaking : You are really testing my memory from 7/8? years ago.
The reason I mentioned the screwdriver tip as I recall that piece is pressed in place.  No glue!!

As I recall I pried up the edges and clamped on with a vice grips and worked it out. To reseat the new one I recall using a piece of 1" PVC pipe with some Vaseline on the edges and tapped it in place.


Hope this helps

A thought