Yamaha Malta

[DownWest]

If I have understood correctly though it is into the cooling water exit channel not into the inlet channel which is the more
normal place for a telltale

Um..might the inlet channel give a false indication? Won't tell if the water is going through the cooling passages of the block & head and if the water is over heated and steaming. Just tells if the pump is working.

Missed post 60..

 

[VicS]

It's normal Vic, but I've thought about it and chose to add mine to the exit so that I get notice of either impellor failure or blocked/restricted channels. I mentioned that upthread somewhere I think, and @pandos may have agreed. (There does still seem to be sufficient pressure at that point to generate a healthy pee). If I missed the bleeding obvious, do let me know because I still don't see why Yamaha et al wouldn't do it my way!

Um..might the inlet channel give a false indication? Won't tell if the water is going through the cooling passages of the block & head and if the water is over heated and steaming. Just tells if the pump is working.

Missed post 60..

Outboard engine telltales usually just indicate that the pump is pumping water up to the powerhead..

You can usually also see some water, that has passed through the power head, being blown out of the exhaust back pressure relief port although this may be no more that a mist or a few droplets.
In may small engines especially older ones this may be the only indication of water flow.

 

[Sandro]

Hi Vic,
yes it works; I don't understand why Yamaha made the telltale in the inlet channel. This way you would only know that the pump is working; would the water jacket passages be completely blocked you would not notice. Moreover with an exit channel telltale you have also a water temperature feeling.
The hole position can also be seen in the picture by Boathook in post #27.

By the way, what do you think of my drilling without dismantling? Have I been too optimistic on the harmless chips removal?

EDIT: Sorry, I started typing at 0900, then interrupted and sent just now, crossing with the other posts I had not seen.
Glad to see I am not alone. Would we be smarter than Yamaha?

 

[VicS]

Hi Vic,
yes it works; I don't understand why Yamaha made the telltale in the inlet channel. This way you would only know that the pump is working; would the water jacket passages be completely blocked you would not notice. Moreover with an exit channel telltale you have also a water temperature feeling.
The hole position can also be seen in the picture by Boathook in post #27.
By the way, what do you think of my drilling without dismantling? Have I been too optimistic on the harmless chips removal?

EDIT: Sorry, I started typing at 0900, then interrupted and sent just now, crossing with the other posts I had not seen.
Glad to see I am not alone. Would we be smarter than Yamaha?

If you know where to drill there should not be a problem. With care most of the swarf should fall away outside.
In this case any swarf that enters is only going to go down the exhaust but if it were more critical some grease on the drill bit will capture it.

 

[Sandro]

Thank you for reassuring me.

Yes, most of the swarf is sucked out by the helical shape of the drill bit but a some little is always found beyond the hole.
"If you know where to drill " and how deep, here is the real danger but just in this case the photos of the open leg made it quite safe. I would not have done it otherwise.

Sandro

 

[Mudisox]

Just shows how useful the forum can be.

 

[6294peterb]

Hi all, I've recently purchased a Yamaha Malta (2.5hp) engine. It's been stored over winter. I filled it up and it started after 2 pulls but dies after a few seconds. I'm new to all this so any advice would be greatly accepted. Cheers Pete.