Impeller Debris in engine

CDory23 · Posted: Fri Oct 16, 2015 9:54 am Post subject: Impeller Debris in engine

I recently had an impeller failure and the impeller broke into many pieces when it failed. There was too much debris and small pieces to be able to collect and fit it back together on the impeller to make it "whole" to see if I recovered it all. I"m now concerned that there may be some small debris in the engine that could create an overheating issue while on the water. Is there any reccomendations on trying to recover any more potenital pieces?

Motor is an 03 Yamaha F40. Maybe pull the thermostat? Is there a screen somewhere? Motor currently is running fine on the earmuffs.

tsturm · Posted: Fri Oct 16, 2015 10:23 am Post subject: Re: Impeller Debris in engine

CDory23 · Posted: Fri Oct 16, 2015 12:02 pm Post subject:

Yes, it was supposedly changed when I had bought the boat and it wasn't time to change it yet.

With that being said I had two bad habits that could have caused this issue.

1. I routinely start my motor dry just before launching at the ramp to make sure motor will run once launched and I don't hold up the line.

2. I would run the motors with the flushing attachment. I now know that with the engine should only be run out of water with earmuffs.

Either or both of these issues could create overheating and turn the impeller brittle which would create this damage.

I will be checking the thermostat housing for debris and running the boat for an overnighter lake trip tonight.

Unfortunately I ran the engines with the flushing attachment for about 10 minutes with new impellers before I realized I shouldnt be doing that. I"m ordering new impellers housing to replace once again even though everything is still running fine on muffs.

Simple stupid mistakes!

tsturm · Posted: Fri Oct 16, 2015 12:40 pm Post subject:

CDory23 · Posted: Fri Oct 16, 2015 12:52 pm Post subject:

yes, the only reason I"m not replacing all of the gaskets is I just replaced everything. I don't think the 10 minutes I ran the engine with the flushing accesory connected could hurt or overheat any other parts besides the metal housing insert and the impeller. I could be wrong.

Don't see what removing the thermostat could do as its for oil temp not cooling water. Taking all visible hoses off and flushing everything possible and inspecting for any old impeller pieces debris.

journey on · Posted: Fri Oct 16, 2015 1:26 pm Post subject:

Well, you've had a good lesson in why one doesn't run the impeller dry. If you don't do that in the future, you can expect the impeller to last.

Though I'm not familiar with the Yamaha engines, removing the thermostat is a good point to start for recovering debris. Removing and flushing the hoses is another good thought.

I'm going to add replacing the impeller to my to-do list this winter. I've changed it once since I got Journey On, new. So that's 5 years per impeller. However, I don't deliberately run it dry.

Boris

CDory23 · Posted: Fri Oct 16, 2015 2:22 pm Post subject:

Ok, there must be some thermostat other then oil temp that I"m not seeing here.

BrentB · Posted: Fri Oct 16, 2015 2:32 pm Post subject:

If it has poppet or pressure relief valve, it can be removed and cleaned

BrentB · Posted: Fri Oct 16, 2015 3:31 pm Post subject:

or replace it

tsturm · Posted: Fri Oct 16, 2015 9:41 pm Post subject:

thataway · Posted: Fri Oct 16, 2015 10:16 pm Post subject:

CDory23 · Posted: Sun Oct 18, 2015 12:28 pm Post subject:

Ok. I was looking at the engine oil overheat sensor. Will take thermostat off today. Thanks.

Engine ran fine on last trip but will still replace impeller since I ran it for 10minutes with flushing accesory.

hardee · Posted: Sun Oct 18, 2015 9:41 pm Post subject:

I would not run the OB's unless they are in the water. I have 2 Yamaha F40's. From my Yamaha Certified mechanic -- "flush the engine after running in salt water. Flush through the hose attachment only, and DO NOT RUN THE ENGINE when flushing. Change the impellers at 300 hours or every 3 years, whichever comes first." So far that has worked. I have over 1000 hours with no engine issues.

The Yamis will start every time. Pump the bulb , and use Marine Stabil every time you fill. That is working too.

Harvey
SleepyC Moon

CDory23 · Posted: Tue Oct 20, 2015 11:16 pm Post subject:

Hardee,

I still believe running the engines with the earmuffs attached on the hose is ok to flush the motors. I'm not sure if you have the fuel injected or carbuerated yami 40s but in my experience and recommendation from mechanic is that these motors should be run at least every 2 weeks. My boat sits on the trailer at home and this is exactly what I do so the fuel doesn't just sit in the carb and potentially clog it. The jets are tiny on the carbed Yamis and when you combine that with the ethanol in todays fuel it does clog these carbs.

rogerbum · Posted: Tue Oct 20, 2015 11:30 pm Post subject: