Help Please! I’m completely losing it!

[KeelsonGraham]

I think I must be going nuts. I'm trying to replace what I believe to be the hose from the freshwater pump to the HX. That's the hose circled in red in the attached photo? Is that right?

Because if it is, then I ordered the correct part from CD, the hose with a 7/8th in internal diameter. But when I tried to fit it on today it's way too big. The existing pipe is on there at the moment and it fits just fine (with its smaller ID).

I don't have some non-standard HX, so whatever is in there at the moment must be standard. So how in hell is it not a 7/8th ID hose????

[robbjd]

I think you need 5/8" hose. Your Sherwood pump has 1/2" ports.

[Ron Hill]

Keel : 5/8" hose is what you need.
I don't know the routing of that hose to the raw water thru hull, but if your hose does NOT make any acute turns you do not need a wire reinforced hose and you can get a replacement hose at an auto parts store!! Heck of a lot cheaper!! $$

Why are you replacing that hose??

A thought

[KeelsonGraham]

Thanks guys. So, it sounds like the catalog part that CD shows is actually wrong?

Am I right that the 5/8th is the outlet from the pump?

[Ron Hill]

Keel : 5/8" hose is both for the inlet and the outlet. I believe that you have the inlet hose circled!!

What I did was to move the inlet hose so it is under the outlet hose. That way you can change the drive belt without having to remove a hose from the Sherwood.!!

A thought

[KeelsonGraham]

The other one definitely has a larger ID. So it looks like I have a 5/8ths inlet and a 7/8ths outlet. Catalina Direct doesn't list any 5/8ths hose at all, so maybe that's what's confusing me. EDIT yes it does, under raw water inlet hose.

Actually, I've also confused myself by thinking erroneously that the raw water pump takes water from the HX. Which, of course it doesn't! So that 5/8th pipe must come straight from the strainer, presumably?

I think I must have hit every branch of the stupid tree when I fell out of it.

[Ron Hill]

Keel : Look at the M35BC engine manual!!

A thought

[KWKloeber]

@Keel

You circled the seawater SUPPLY elbow (a 1/2" NPT elbow/inlet to the PUMP) and its hose barb is 5/8" ID HOSE.

If you follow the hose (easily done) you'll see that it DOES NOT go to the Hx - it comes from the 5/8" barb on the seawater thruhull (or strainer.) 

The hose from the TOP hose elbow (which is also 1/2" NPT but 7/8" ID HOSE) goes to the Hx.

I previously posted resources on this forum showing the "B engine" hose routing and it is on the wiki:
https://c34.org/wiki/index.php?title=Flow_directions_in_engine_cooling_hoses_(both_early_and_B-series_engines)

Cheers
Ken

[KWKloeber]

@ Everyone

On EVERY Universal engine. EVERY ONE. The pump (facing it) turns CLOCKWISE, so it is easy to tell which hose barb the impeller SUCKS from (raw seawater from the thruhull) and which hose barb the impeller PUSHES through (to the Hx.)


**I have climbed the stupid tree and I own one in the backyard**!!

EDIT:

I've also confused myself by thinking erroneously that the raw water pump takes water from the HX.

Also, many believe that the freshwater coolant pump "pumps" from the engine, TO the hose on the front of the gear cover. 
It DOES the reverse,  the coolant pump SUCKS from the hose on the gear cover and pumps coolant TO the engine block and TO the Water Heater (via the hose barb on the of the freshwater coolant pump.)

 

[KeelsonGraham]

Keel : Look at the M35BC engine manual!!

A thought

I did, the trouble is it shows the hose ends going into the HX and it shows the water pump end in a separate image, minus hoses and minus labels telling you which is the inlet and outlet. There's no diagram showing the overall hose layout.

[KeelsonGraham]

Thank you Ken, those are excellent pics.