SeaWater Exit on 7.4L w/ Bravo One???

[Darin Jordan]

When I'm running my 1990 Maxum w/ 7.4L Bravo One, the bulk of the fresh-water being drawn into the system appears to be exiting from up near the transom, coming out around the steering gymbal/mounting area. Is this correct?

I'm only asking because while I have it apart for the other work I'm doing, I just wanted to make sure that there wasn't anything else I needed to fix as well. Looking at the diagram in the manual (cooling system - 6B37), it appears that all the fresh water exist through the exhaust, so I was expecting to see the water coming out through the lower unit down near the cav-plate or through the prop hub (does this unit have through the hub exhaust??)... but the bulk of the water comes out as described above, up near the transom from under the steering gymbal assembly, by the outdrive mounting plate.

 

[HT32BSX115]

Re: SeaWater Exit on 7.4L w/ Bravo One???

When I'm running my 1990 Maxum w/ 7.4L Bravo One, the bulk of the fresh-water being drawn into the system appears to be exiting from up near the transom, coming out around the steering gymbal/mounting area. Is this correct?

Completely normal.

 

[Darin Jordan]

Re: SeaWater Exit on 7.4L w/ Bravo One???

Completely normal.

Phew! Kind of what I thought, but I couldn't really tell by looking through the service manuals... That's a relief!!

Thanks...

 

[Fishermark]

Re: SeaWater Exit on 7.4L w/ Bravo One???

That's a relief!!

Ironically enough I think you are literally correct. I think those are called exhaust reliefs.

 

[Bondo]

Re: SeaWater Exit on 7.4L w/ Bravo One???

but the bulk of the water comes out as described above, up near the transom from under the steering gymbal assembly, by the outdrive mounting plate.

Ayuh,.... It's entirely Possible that if it's Ever been run without a solid flow of Water,...Even a short time,...
The Shutters might have Burnt Up,...
And fallen down into the lower pipes, causing the flow to be diverted to the Idle Relief ports....
Without knowing any History of course,....

 

[Darin Jordan]

Re: SeaWater Exit on 7.4L w/ Bravo One???

Ayuh,.... It's entirely Possible that if it's Ever been run without a solid flow of Water,...Even a short time,...
The Shutters might have Burnt Up,...
And fallen down into the lower pipes, causing the flow to be diverted to the Idle Relief ports....
Without knowing any History of course,....

Hmmmm... Well... I haven't run it without water flow since I've had it, and I don't think the previous owner (my late father) did either....

So, these "idle relief ports"... I'm assuming these switch once off-idle to divert the majority of the water down through the unit with the rest of the exhaust?? What is their purpose? How does one inspect them?

I'll go look in the manual to see what it says....

Better safe than sorry....

 

[Don S]

Re: SeaWater Exit on 7.4L w/ Bravo One???

They are alway there, and always open. Exhaust comes out of them too when off idle, but the exhaust and water are all looking for the path of least resistance. At idle, it's through the idle relief ports (IN the water) and through the prop at speed (in the water)
On land and on muffs, the water usually come out the idle relief ports first simply because the boat is usually bow down. (again) path of least resistance.