Plastic prop hub (Quicksilver) melting

[michaelshilling]

Evinrude 250HO. Burned up the third quicksilver plastic hub (square). Melted, then spun inside of prop. Went through entire water system, no issues. Has anyone ever seen this? Thanks.

[ThomasD]

Check cooling passage hole on trim tab.

[michaelshilling]

Not sure exactly where you mean.

[cwilt]

Not sure exactly where you mean.

Screenshot_20211001-195903_Gallery.jpgScreenshot_20211001-195903_Gallery.jpg

This is the hole. Different manufacturers have different styles.

[1BADAIR]

evinrude exhaust is very hot. Reason they went to the TBX hubs. What year is it? 05/06 they had a cooling kit you could add. They have acooling hose off the back of the block that could also be blocked

[michaelshilling]

I am running a Merc Tempest, so only the quicksilver will work. Is there a TBX for a 2008 250HO M2 gearbox with a mrec prop?

[michaelshilling]

​20211010_084316.jpg20211010_084312.jpg20211010_084304.jpg Think this could be the cause?

[michaelshilling]

My thought is this intake rarely sees any water above 60 mph https://studio.youtube.com/video/UieWcO2qikI

[Ranger391v]

I've got a '09 250HO w/M2 ......... your sacrificial anode is correct. It should be flat and have a square cut intake hole.

Yours does look like someone probably repainted the gearcase and didn't coverup the anode ...... and it looks like it has been struck by the prop blades at some point (both the streaks and the square hole looks rough in that one corner with a chunk taken out).

You never said how quickly you're melting down the Merc hub .......... but I've been running a Fury4 for about 3yrs now and have not had a problem.

With all that said, I think you're not getting enough cooling water on it. Chances are there is a passage somewhere that's not flowing enough.

You might want to try posting this on the JohnRude board and let those guys try to help. Just make sure you post your model number, etc.

[ThomasD]

​20211010_084316.jpg20211010_084312.jpg20211010_084304.jpg Think this could be the cause?

My money is on this. Before your prop chopped the front off there was an opening that funnels water to the exhaust to cool it as it goes through the lower unit. Etecs run very lean and have higher exhaust temps then other 2 strokes. This is causing the prop hub to melt on extended high speed runs.

[Ranger391v]

My money is on this. Before your prop chopped the front off there was an opening that funnels water to the exhaust to cool it as it goes through the lower unit.

The eTec sacrificial anode DOES NOT have a 'scoop'. It is merely a square cut hole. The OP's is correct ..... with the exception to it looks like someone painted it when repainting a gearcase, prop blade tip strikes, and the blade tip 'chipping out' the one corner of the 'square cut hole'.

[KandKKustomz]

Try a michigan wheel xhs #200.. I ran a etec 200ho and a 225 ho w merc props neither melted a merc insert. I run the xhs #200 and like it better then the flo torq

[Procraft180Pro]

I’m having the same issue with my 05 Yamaha F250 running a Merc Rev 4 prop. Ran fine for 5 seasons, but now I’ve melted 2 Flo Torq inserts in 3 trips. It’s a saltwater boat with only 290 hours on the motor. Religiously flushed with Saltaway after every use.

Solved: Sure enough, the hub cooling line from the trim anode to the hob was clogged with salt.