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21 195S won't launch

Phang

Member
Messages
11
Reaction score
3
Points
12
Boat Make
Yamaha
Year
2021
Boat Model
195S
Boat Length
19
Hi all, Well I just change out my impeller and wear ring on my 2021195S and the boat won't accelerate or launch like it use to after the replacement. Before the replacement if I would just WOT at a dead stop the boat would launch up and go but now with the replacement. If I do that it would just rev up like when seaweeds gets stuck in it. I would have to slowly accelerate to about 10 mph to pick up speed then at that point I can slowly accelerate to top speed. I do get up to the same top speed as before. Just can't launch at at dead stop like it use to. Any help would be greatly appreciated! **The impeller and wear ring was replace with OEM**
 
Seems that something didn't go back together correctly. Why did you need to change the impeller and wear ring on such a new boat?
 
Seems that something didn't go back together correctly. Why did you need to change the impeller and wear ring on such a new boat?
I think I saw on a different thread that he had sucked up a rock.
 
Seems that something didn't go back together correctly. Why did you need to change the impeller and wear ring on such a new boat?
It seems I did put everything back. The big different is that I only hand tight the impeller and didn't torque it.
 
It seems I did put everything back. The big different is that I only hand tight the impeller and didn't torque it.
Coming from an aircraft mechanic background - I'd say that's probably the problem - and risky! I've seen improperly torqued items that spin at high speeds similar to an impeller in catastrophic failures. The result is never pretty and I've been fortunate enough not to experience any loss of life, however, the damage is usually extensive. I think (hope) that you are implying that you have identified the problem and will take the proper corrective actions?
 
The impeller is reverse threads and will self tighten. Just needs to be not loose when you reassemble.
 
Something is causing cavitation. What is out of place inside the pump tunnel?

What is the gap between the impeller and pump housing?

Did you install the correct impeller? I believe the 195 uses a larger diameter impeller than the normally aspirated 1.8s.

How is the caulk in the cracks in the pump tunnel?
 
Bet the problem is the silicone in the joints. Has to be perfect.
 
Something is causing cavitation. What is out of place inside the pump tunnel?

What is the gap between the impeller and pump housing?

Did you install the correct impeller? I believe the 195 uses a larger diameter impeller than the normally aspirated 1.8s.

How is the caulk in the cracks in the pump tunnel?
This is the impeller I got:

Yamaha - Impeller - 6GN-R1321-10-00
 
The impeller is reverse threads and will self tighten. Just needs to be not loose when you reassemble.
I see- that makes sense. I digress - my mechanic ocd took over for a minute! One too many failures due to things not being installed correctly.
 
This is the impeller I got:

Yamaha - Impeller - 6GN-R1321-10-00


Partzilla shows that part number for a list of boats, nothing 19' and nothing newer than 2010.

You sure that's right part?

Edit: yamahapart.com shows it's right, weird.
 
Have you measured the tolerance between the impeller and the housing? I think the max gap is 3mm. I'm on vacation and don't have easy access to my manual.
 
Perhaps a dumb question, but are you sure you reattached the bucket to the cable?

And: pics would help, if you can get them. Side shot of the jet; shot up the intake...
 
Have you measured the tolerance between the impeller and the housing? I think the max gap is 3mm. I'm on vacation and don't have easy access to my manual.
I didn’t measure anything. I thought it was plug and play. I will say that when I clean out the port recently I can feel the impeller closer than when it was stock. Like I can just touch it right away as before I have to reach back to touch it. Was I supposed to measure it? And if so how? Thanks
Perhaps a dumb question, but are you sure you reattached the bucket to the cable?

And: pics would help, if you can get them. Side shot of the jet; shot up the intake...
I did attach it. But it was something to look at.
 
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