Changing oil---warming up on the hose...funky noise..

[Mandelon]

I want to change my oil. This is a BBC 454. Aluminum pan, with a hose drain on it already.
Obviously I want to warm up the motor so the oil thins and runs out more easily.
I put a tee in for the water intake. One side to the motor and one for a hose stuffed up into the intake grate. Not so far as to hit the impeller though. I checked. I did see the impeller blades are a bit nicked up.
So I fire it up, and it makes a clatter from the housing where the shaft and the engine meet. I shut it down and checked out what I could see.
Is this the u-joint? Around the thrust bearing it seems to be lubricated well. I see there is a zerc there so I will grease it up tomorrow.
Is this noise a big deal? Can I run the engine for a few minutes?
Do I need to disconnect the shaft? If so how do I do it? Never had a jet before.
I have never noticed this noise when the boat is in the water. We are leaving Tuesday for Parker.

[Rexone]

The noise you're hearing is likely the clearance between the driveshaft yoke and the pump shaft splines. You don't hear it in the water as much because the impeller is loaded and not rattling back and forth on the spline as much. Some boats will hear it at idle in the water as well depending on the clearance. The noise, if that's what it is, is nothing to worry about.

[Eric455]

ohhh man u screwed up ur motor now you cant make it out to OP6C. ohh ohhhhhh... jawdrop dont worry man j/k u'll be fine rexone couldnt of said it better.
eric

[Mandelon]

Alright. Thanks, guys. I will run the motor tomorrow and change out the oil.
Eric, why do you like to give me a hard time? I may have to steal some of your high school girls at OP6...

[Taylor LP]

A lot of people hear that noise even in the water and think they have a bearing going out.
The noise should go away (in the water) when you get it just above idle.
If it doesn't, feel the bearing housing after a good run. If it's anything more than warm, you better get that bearing replaced. If it fails it's bye-bye impeller. One of those "pay me now or pay me later" things. Now will be much cheaper than later!