New Manis/Riser. New pump. Overheating. (UPDATED: RESOLVED)

[Philster]

1996 Mer 502 Magnum. 315 Hours. Bravo One. Salt water boat. Rack stored and flushed regularly.

Last run, she got hot @ 200*.

Since then:
She has been tuned up.
New belts.
New Manis/risers (was due)
New water pump kit.

Now... She runs hot (my merc tech called ). Say that they can see some bubbles in the clear plastic fitting of my flush out. Explains it is common for the water tube coming in from the drive (at transom) to be squeezed or corroded. Will check t-stat and wants to pull the drive to get to that hose/tube.

Thoughts? First few times out this year, she ran at 175-180. No signs of trouble.

 

[Don S]

Re: New Manis/Riser. New pump. Overheating.

Re: New Manis/Riser. New pump. Overheating.

Air is why it's overheating. If they can see air in your clear hose, I would be looking at the air leak there insteads of the transom hose.
An airleak on a flushing system will prevent water from being sucked into the pump.

 

[Philster]

Re: New Manis/Riser. New pump. Overheating.

Re: New Manis/Riser. New pump. Overheating.

Don S, I just took a mind-clearing lunch walk... and wanted to add this:

The flush kit was installed after all my good runs. Since she is a rack-stored boat, an internal flush kit was needed (goes from water to an indoor rack via forklift). So, I ran her good a few times/days, went into the service office and told 'em to put a kit on 'er.

They did. Next time out, she was running hot. I don't like these kind of coincidences, and if there is air, the leading suspect is definitely the flush kit at this point!

I come back from my lunch walk, I sit down, and read your post, and called my merc service manager to remind him of the chain of events:

Ran hard and fine
(noted steamy exhaust)

Ran hard and fine
(noted steamy exhaust)

Flush kit installed
Ran hard and heated up

Invested in maintenance mentioned.

Finally, they ran it hard and noted engine was strong but temps rose and bubbles were visible.

:::just hung up phone with service manager::: Okay, he says he will check the flush kit, but feels (based on his experience with Bravo Ones on boats this old) that the hose coming in from transom is leading culprit.

 

[Philster]

Re: New Manis/Riser. New pump. Overheating. UPDATED INFO!

Re: New Manis/Riser. New pump. Overheating. UPDATED INFO!

RESOLUTION

Removed drive.

Removed/Replaced hose coming in from drive (after waiting a day for the special tool to connect the new hose).

Replaced drive.

Corrosion had almost closed off the old (likely original) hose.

She runs 160-175 now.

Let the cooling waters flow. Take note of this if you have a cooling issue, and all your other pieces are new.