How much water?

[Bob707]

Anyone know how much water should flow from the prop when you run the motor on the flush muffs?

 

[steelespike]

Re: How much water?

I guess that would depend on how large the telltale is.

 

[QC]

Re: How much water?

And what motor. There are tests for this stuff. Let us know what exactly we're working on here and I'll move it to the appropriate forum. Not really a prop topic. Welcome aboard BTW

 

[Bob707]

Re: How much water?

Thanks very much for your help. The motor is 93 yamaha 225. Tell tail stream is very good. Sorry to post in the wrong forum. Trying to diagnose a spun hub problem. Prop guy says I must not have enough flow. I ran it with muffs and at idle I get a little running out the hub.

 

[QC]

Re: How much water?

OK. Going to move to the Yamaha forum. They'll get you squared away.

 

[Capt Ken]

Re: How much water?

Huh? Water flow equates to spun hub? That's a first. Find another prop guy. All water except for what comes out pee tube exits out the prop. If you was not getting enough water flow, you would be running hot. Sounds like the prop guy is grasping for excuses.

 

[QC]

Re: How much water?

I didn't want to comment as I don't know Yammies, but seemed like as much of a stretch as the guy counting exhaust out the prop has thrust . . .

 

[TwoFish]

Re: How much water?

If you do suspect a spun hub for reasons other than water flow it is easy to diagnose. Put a mark on the inner hub and another on the outer hub. Make sure rubber section is between the two marks. Take the boat for a run. Do a few quick starts. If the marks don't line up anymore the hub is spinning.

 

[99yam40]

Re: How much water?

Yes I have heard of prop hub getting to hot from lack of cooling and causing problems, but I do not have enough knowledge to help you trouble shoot the water flow through it.

Make sure lower anode is in place as I have heard that does effect prop cooling on some motors some how

 

[etracer68]

Re: How much water?

Im not sure about Yammies, I have a 1987 90HP Johnny. I have two water outlets that are at the top, backside, of the midsection. As I understand, these outlets are for high end rpm, the water cant pass through the thermastats fast enough at higher rpms, there are two spring loaded water passages between the thermostats, that (springs) compress at high rpm, and water pressure, and dump out those two holes, upper backside of midsection. It still should be flowing water through the prop to. Maybe you have a part blockage, and its heating the hub. Just my .002, and dont know if Yammies have the same setup.

 

[Capt Ken]

Re: How much water?

The exhaust relief holes are a thing of the past. They were for slower speeds where it reduced the back pressure on the engine until the boat started moving through the water fast enough for the exhaust to get sucked through the prop.
If the exhaust is getting hot enough to cause the hub to slip then the engine is fried.