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Hello to all and a question, I am stumped with a raw water impeller issue.

I replaced the complete water impeller assembly, lower housing, thermostat with over-heat sensor on my 2007 Yamaha 90 two stroke roughly two month ago. After remounting the lower unit I soon started the motor using the "ear muffs" and all went well. I purchased a portable outboard water flush bag a short time after and used it about a month ago and again with good results.

Yesteday I decided to start the outboard again using the flush bag. I filled it to the appropriate level as before with a slow but steady supply of fresh water to maintain it filled (it has a 40 gallon capacity) for the sake of spillage during the run cycle.

The motor fired right up but I noticed no water flow from the "tale-tale" on the lower cowling, a bit of steam was visible. I shut the motor off after a minute and waited a bit thinking that maybe the thermostat hadn't opened. Re-started and again no flow from the "tale-tale", I let it idle for a few seconds and shut it down again and waited a bit longer for a third attempt.

On the third attempt after a few seconds of idling the "over-heat" alarm went off and I shut it down immediately. After a few minutes of cool down I connected the powerhead flush line and ran fresh water through the motor to cool it further. During this step water flowed from the "tale-tale" at a good rate. I removed the flush bag and tried with the "ear-muffs" for a final attempt. I thought to try and push water up for a result but none was achieved.

It appears the new impeller has failed and with less than a 1 hour total run time and with no salt water exposure. Any ideas what could cause a new impeller to fail so quickly and with just idle run time?

I did view very small black sediment in the flush bag which I fear may be from the impeller along with what I think are salt crystal that I have been flushing out from the powerhead since the original lowerunit removal. I thought I had flushed it out but it appears to still be present. There was a significant amount of this build up in the area of the thermostat cavity which I scraped, brushed, vaccumed, water flushed, and blew air on to remove.

Any suggestions will be greatly appreciated as I alocate time to remove the lowerunit once again for inspection.

Thanks,
Angel M.

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I also have a B90 and I replaced my pump and thermostat (for the first time myself) late last season. This spring when I was checking everything out I noticed the same thing and thought the same thing as you but I replaced the thermostat first and thankfully that turned out to be the issue.

When I pulled the old thermostat I was amazed how much salt and crap was in there even though I do flush after each use. I took out the the old thermostat and blasted it with a hose and put it in a pot of water on the stove and it did function (although I'm not sure what temp it's supposed to operate). For $24 I just left the new one in there and I'm keeping the old one in my parts bag for a backup.

When I researched DIY water pump repair a big issue to watch out for is making sure the new impeller blades bend into the cup in the direction they are supposed to spin or they will burn up quickly.

Another test to confirm it is the pump is to remove the thermostat and run the engine in a tub of water with no thermostat. The engine will run cold without the thermostat but it won't hurt it, if the pump is working it will pee a full stream, if not then you either have some blockage along the line or your pump is shot.

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Thanks Whalerbob for the reply.

I detailed in my post that the "tale-tale" or pisser functioned with a good stream when I connected the hose to the powerhead flush port. I didn't mention in the post that I used this flush port various time to better cool the block after the 3 failed attempts during start-up.

Yes, I did rotate the new impeller correctly (for the sake of the vanes) when I assembled the upper pump housing. I coated the inner stainless impeller cup and the impeller vanes with the appropriate Yamaha grease for the initial start-up 2 months ago. It has functioned twice in the last 2 months using either the "ear muffs" or the flush bag and both times it operated at idle for approximately 10 minutes with no issues.

I do remember when I installed the impeller that it fit onto it's shaft position with much effort (and yes it was aligned with the woodruff key). I inquired with a buddy with similiar Yamaha 90 regarding this fittment concern. He mentioned his impeller went on with some effort but not as difficult as mine sounded.

I am not to keen on starting the outboard with the thermostat removed, I will remove the lowerunit sometime this week and see what went wrong.

Thanks,
Angel M.

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Have you tried replacing the thermostat? $24 and 5 minutes might be worth it to know and even if it's not the problem you can keep it for a spare and use it the next time.

Funny thing about running the engine without a thermostat, what prompted me to check mine in the first place is my engine was running with the symptom of "running cold" so a mechanic friend told me to check my thermostat to see if it was stuck open. Mind you this was the first time I had ever tried to replace it myself so I was confused when I popped the cap and the only thing in there was the rubber ring from the old thermostat. Upon further investigation it turns out the thermostat had completely disintegrated thus I was running for some time with no thermostat at all.

I suppose the spring is somewhere in the bowels of my engine but it's running fine the way it is so I'm not going to mess with it.

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I have never heard of a flush bag and find the idea suspect.

Running the motor on the muffs with a hose allows the proper water pressure to cool the motor.

I would proffer that the use of the bag led to insufficient water when cleaning and burned up your impeller.

If the tell tale does not flow water within 10 seconds, turn off the motor.

There are hundreds of boaters who slip their boats and only flush 2x a year.

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Hello Phil T, the flush bags have been around for a good while now, since the mid 80's. The model I have holds 40 gallons of water and water level is just above the cavitation plate, a garden hose is still attached and keeps the bag properly filled.

Why would you think the flush bag could cause impeller failure? It only simulates the lowerunit being submerged in either ocean or fresh water. The impeller must draw water on it's own in either submerged condition. The outboard is only run at idle just like the "ear muffs".

After my initial impeller rebuild I started the outboard on the "ear muffs" and ran it for a least a good fifteen minutes but not continuously. During that period a good stream of water was present at the "tale-tale" pisser.

I used the flush bag a couple of weeks after the initial impeller break in. The "tale-tale" showed no issues then. One of the advantages to the flush bag is less exhaust noise and 2 stroke smoke. One other advantage with the bag is, one can add a bit of cleaner (degreaser, etc.) to the water mix for a thorough flush of salt contamination a least a couple of times a year.

I will know better what the failure is when the lowerunit is removed.

Thanks for the inputs...
Angel M.

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Here is a paragraph from a Boat US article on outboard flushing techniques. I have included the web link for all interested. For Phil T, there is a picture of a similar flush bag that I am using. I purchased the next model up which has a larger foot print so as to better accomodate my lower unit, it's actually for larger H.P. outboards so I benefit from better submergence and water capacity.

Yamaha

Yamaha gives three choices — with a flush bag, muffs, or hose-port connector Ñ and says all three methods work equally well. Bag and Muffs: Engine should be vertical, run no more than 800-900 rpm in neutral for 15 minutes with the prop removed. Be sure the engine is receiving cooling water (by checking the overboard indicator). If your outboard has more than one set of cooling inlets, a flush bag should be used. Flushing Port: Engine should not be running; it can be tilted or vertical. Prop should be removed. Flush for 10-15 minutes.

This is the way I did my Yamaha with the "ear muffs" and later with the flush bag.

The link:
http://www.boatus.com/magazine/2013/A...ht-way.asp

Hope this information helps clear some myths about flushing.

Angel M.

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The water pump must be submerged for it to operate.

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We are in agreement huckelberry145. My lower unit was while in the flush bag but obviously not with the "ear muffs". The lower unit removal and disassembly of the impeller housing will hopefully shed some light on the culprit.

Till then...

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Angel -

Thanks for the information on the flush bag. One learns something new every day.

In reviewing the information and re-reading your posts, one thing popped out...



Why would you add degreaser to the water cooling system? I have only read about using a de-salting product such as this:
http://www.amazon.com/Salt-Away-Mixer...B003HFVOF0

While it is your choice what to use, I, personally, prefer 100% clean water via muffs.

For the overheat alarm to go off, you must have some blockage in the water channels in the head or a tube restricted. I would investigate the flexible tubing that is on the block as well as the section that feeds the nozzle in the uppercase.

The sound of my 1987 Yamaha 90 2 stroke was not too bad on the muffs. Even my neighbors 20ft away didn't mind.

I am interested to learn the results from the disassembly.

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Hello again Phil, degreaser was just an option since I've come across a web articles where the individual or mechanic was suggesting it. They were specific in suggesting only the "Simple Green" brand and no other with a mild 10 to 1 mix ratio if it makes a difference.

I use "Salt Away" currently but the hose attachment for a motor flush is a bit of a (P.I.T.A.) at times. Added into the flush bag may be a better solution for me at least.

When I first did the disassembly a couple of months ago I discovered quite abit of salt contamination within the thermostat assembly and block cavity. I cleaned and flushed all that I could access till water drained clean from brass feed tube and exhaust manifold within the mid-section. Phil I was surprised to see a decent amount of salt crystals or sediment still coming out from the motor. The sediment was visible in the bottom of the flush bag.

While I worked on the lower unit (which took a few weeks due to a repaint) I had taken the time to spray/coat the thermostat block cavity with ample amounts of "Corrosion X" in hopes of breaking down any corrosion that was unseen further into the block water passages.

I did thoroughly water flush the penetrant/lubricant from the block prior to remounting the lower unit. There may have been some oily residue coating left but that should not have affected the impeller but, it may still be reacting with any present corrosion in the water passages. It's possible that the sediment has/had accumilated in the impeller assembly (by gravity) and tore up the impeller.

Phil what flexible hose are you refering to? I did inspect the "tale tale" hose and cowl fitting for blockage along with the block port which feeds it. To further cool down the powerhead and during each test of the impeller issue I connected the garden hose to the block flush port attachment and a strong water flow was visible at the "tale tale" pisser. I suspect the strong flow was due to the thermostat being open at temp.

I feel that there is no blockage within the powerhead assembly at this juncture. I'm hoping it's not the impeller but maybe a rubber grommet failure where the brass water feed tube connects to the top of the impeller housing.

Thanks again for the input...
Angel M.

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The circumstance of the original post was exactly one I encountered following impeller replacement on my 1991 40hp Yamaha back in 2011.

In my case it was the feed tube being incorrectly seated or mated with the impeller housing. It is not easy to get right without a helper and a good light shining between the upper and lower units.

I think the impeller vane issue is very real.....again the whole assembly process is just fiddly enough to cause one or other vane to pop into the wrong direction.

God I wish there was a mesh like a stent to prevent a broken impeller from lodging in the upper unit potentially killing an outboard.

Finally thermostat replacement is so easy and inexpensive I wonder why one would not do it at least every other year.

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Hello docsoma and I hope my situation is as simple as the brass feed tube and grommet misalignment. I did coat the stainless impeller cup and rubber veins well with Yamaha's higher grade marine grease in anticipation of the initial break-in.

Hopefully the impeller is not compromised. I am quite certain that the impeller veins collapsed in the correct direction during the re-assembly but, I am a firm believer in "Murphy's Law".

I will attempt removing the lower unit this evening if no thunder storms are forecasted for the Miami area yet again.

Docsoma I did replace the complete thermostat assembly with O.E.M. parts (impeller assembly as well). That included Thermostat, poppet valve and spring with rubber grommets/seals and gasket. Also I replaced the Over heat block sensor which mounts next to thermostat cover just above number 1 cylinder.

Please keep in mind that the Yamaha did start and run on two previous occassions for a minimum of 10 minutes with no apparent issues, that's what is baffeling me. The Dauntless has not been put to water yet since the rebuild.

Till the next update, thanks to all for the inputs...
Angel M.

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Hello W/C and an update on my impeller issue.

Pulled the lower unit off a couple of evenings ago and got into the impeller housing. Catastrophic failure of the impeller, stainless internal cup, and upper plastic housing. Impeller had only one remaining vein, the other 5 looked as if a dog had chewed them off. A definite melt-down occured, so severe that it caused the stainless cup to rotate almost 135 degrees within the upper housing which inturn caused a misalignment of the drive shaft and cup's center hole.

Remember that the impeller assembly is not concentric to the drive/input shaft. When the cup rotated the misalignment caused the edge of the center hole to rub against the shaft diameter. It put a wear ring on the shafts diameter at that location, not severe but I had to lap and polish the affected area for burrs.

I removed the thermostat cover, thermostat, and "poppet valve" with spring for further inspection. The block cavity for the thermostat was clean of any impeller debris but more salt crystals where present. I back flushed the powerhead from the thermostat area and no rubber or plastic debris was visible. Water flow through block, "tale-tale" motor flush port, and brass feed tube was excellent. I did seem to flush out a bit more of those salt crystals or sediment as with the first time and when I used the flush bag recently.

I will be ordering all new O.E.M. parts once again but I have a question. When I rebuilt the impeller assembly last I encountered some difficulty in getting the impeller to slide down the shaft and onto it's woodruff key. I had to resort to using a length of P.V.C. tubing that had the appropriate inner diameter as a drive bushing and with a moderate dead blow mallet persuade the new impeller to seat itself. From my web reviews it appears that most impeller replacements require minimal hand press force to seat the part. Can any member here with a Yamaha 90 2 stroke relate to this experience.

I am beginning to suspect that I may have originally received a defective impeller (with a smaller inner diameter)and I failed to properly seat it. The failure indicates that the new impeller was in direct contact with the stainless cup because there is barely a hint of contact on the lower stainless flat gasket that mounts atop the lower (aluminum) pump housing. I will post pictures taken during the dissassembly but any input on impeller fittment will be greatly appreciated at this point.

Thanks to all...
Angel M.

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Pictures of my impeller assembly damage have been uploaded to my Personal page for those that might be curious to view.

I am not planning to leave the pictures up for any length of time, this is one ordeal that I would certainly like to forget.

As I asked in my previous post, if any member here on W/C has done an impeller replacement on a Yamaha 90 2 stroke and was able to press the replacement impeller down on the input shaft with minimal or with hand press force I would appreciate hearing about it.

Thank again to all who have previously posted to my issue.

Angel M.

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Angel, I believe you are on the right track in analyzing your pump issues. While I have not done a Yamaha water pump overhaul, I have worked on many Evinrude, Johnson, Mercury, Mariner, and Honda outboards over a 50 year period. On all those engines (plus the few inboard engines and inboard/outboard pumps), I never had to tap on the impeller over the shaft. They all had what I would call a snug sliding fit. No tool required to slide them down. Sometime, the corrosion or exhaust deposits on the drive shaft will require cleaning to bare metal to prevent the impeller from hanging up. Some fine grit emery cloth or steel wool usually is all that is required to remove these deposits. I am certain your impeller should be a sliding fit. It has to be in order to center itself between the lower wear plate and the upper/top pump housing surface. During operation, the drive shaft will move slightly due to vibration or temperature changes/thermal growth. The impeller must center itself in order to prevent the extreme binding that you experienced.

I do think that you either had a defective impeller (smaller inside diameter or out of spec) or you somehow got the wrong impeller/incorrect part. Mistakes can happen.

I would bet that with the proper impeller and the proper sliding fit on the shaft, you will have no further issues.

Al

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Nice pictures of an ugly situation. I really like the jig holding your lower unit, did you fabricate it?

There are a couple of master Yamaha techs giving advice at: http://www.yamahaoutboardparts.com/fo...om/forum2/
Looks like you could use some expert advice, be sure to state your engine model number.

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Thank you Al for your input and sharing your past observations/experience. I was really beginning to second guess my mechanical abilities with this incident.

Al regarding the corrosion and exhaust contamination that can be present on the shaft and impeller area, I did thoroughly clean and polish the the entire visible length of the shaft right down to the upper gear case bearings when the lower (Aluminum) pump housing was removed.

The replacement impeller would just barely press onto it's diameter with applied hand force which I found to be very odd. I called a friend immediately with an older version of my motor who had recently done an impeller change. He recalled having to tap his into position but with no great force, nothing similar to what I was describing to him.

Al so in avoiding another similar impeller incident the next replacement should (with a light to moderate hand press) fit the input/drive shaft, correct? As I did before, lightly grease the impeller I.D., top and bottom contact area's, and it's immediate shaft area, correct? Apply a light grease film to the stainless cup and impeller vein edges for the initial first start,correct?

I just want to cover the basic's with this assembly, the remainder I can handle well.

Thank's again to all that posted...much appreciated.
Angel M.

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sounds too simple but are you sure you had the impeller vanes rotated into the cup in the proper direction?

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Hello tmann45 and yes to your question.

I fabricated this fixture before removing my lower unit, it attaches to an engine stand that I have. I used the fixture during the initial disassembly and asembly, for repainting the lower unit and now again for this mishap. The fixture is very handy, it allows me to rotate the assembly 360 degree's when needed.

The fixture is modular so it should accomodate various lower unit makes and size if ever a buddy should have need of it. It's composed of steel angle with MIG'ed (right angle) members for attachment to engine stand face plate. The lower unit mounting struts are Aluminum length's with round Aluminum stand-offs for fixture clearance. One end of the Aluminum struts have machined "bolt/fastener" slots for position adjustment and better centering of the lower unit within the fixture.

Thank you for the link provided, I will certainly check out the available information and help.

Angel M.

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Hello Brooks89 and yes I properly referenced the impeller vein collapse direction.

When I remounted the lower unit the spline engagement was slightly off, so I had to further rotate the input shaft. It rotated without effort and in the direction of the vein collapse.

Angel M.

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I've got to say, Angel, those photos seem to show the impeller melted to the housing from a lack of water.

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Hello Wing15601, it would appear that way from the pictures if no explaination was offered.

Repeating from my initial post, the outboard was ran for approximately 10 to 15 minutes (not continuosly) on two separate occassions roughly a week or so apart and without incident. Initial start-up after re-installing lower unit (impeller rebuild) with motor run on "ear muffs". Second start-up as described above (time and date wise) was done with 40 gallon flush bag and steady fresh water supply and again no incident. The "tale-tale" produced a steady uninterupted stream with each event with the exception of last Sunday (third start-up and a month after last run cycle).

Al who posted previously and recounts his personal outboard repair experiences feels that my description of how the impeller went onto the input shaft may be the smoking gun. I would be the first to admit and wouldn't have bothered posting to W/C if it would have been a situation of failing to supply water to the outboard.

This isn't my first powerboat and I am quite capable of doing most major repairs and maintanence as long as information (shop manuals) or "factory how to secrets" are available. No where on the web does anyone really detail how the impeller is suppose to press/fit onto the input/drive shaft, "my bad" with this incident.

Thanks again for the input...
Angel M.

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Angel, it sounds like you did all the right things. I agree with wing15601 that at some point, water was absent and the heat buildup caused the impeller to self destruct. While part of this may have been caused by an impeller that was too tight on the shaft, I am now wondering why the stainless cup rotated in the plastic impeller housing. While I am not familiar with the Yamaha configuration, most similar pumps prevent the cup from rotating by a tab or bent circumference to keep the cup in place. Is it possible that the cup rotated, blocked off the discharge port (thereby shutting down the pump's ability to move water) and once the pump was no longer pumping, the impeller failed?? I would not expect even a dry pump to be able to rotate the stainless cup. A dry pump would certainly cause the loss of impeller vanes, but the cup should remain in place and not rotate even under that scenario.

I recommend you go back to the basics when you reinstall. Check to make sure the intake is clear from the screens up to the pump. Check to make sure the engine passages are clear of any debris. Check to make sure you have the correct parts. Double check the vane direction (if engine rotates clockwise when viewed from above, you must either rotate the shaft clockwise or the impeller housing counter-clockwise). Check the anti-rotation features of the stainless housing cup and insure it is seated when you install the pump housing.

Sure wish I was close by to help, and hope the next installation goes without any problems.

Al

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Angel -

I was refreshing my memory on the impeller replacement and searched Youtube. I see one for a 1990 50hp Yamaha and after viewing it, it got me thinking:

Were you able to get the wooddrif key out of the shaft?
Did the new impeller line up with the key?

While it does not show these steps, take a look at the video and see if you might see a cause for the failure. Note, I personally disagree with the author about not changing the wear plate and o-rings.

http://www.youtube.com/watch?v=sB8lHE...D8D07801E1

If this doesn't help, sorry for the tangent.

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Hello again Al, yes the stainless cup has a formed/stamped tab for locating within the upper housing. As wing discussed and I will agree, at some point the pump unit failed to draw any water thus the over-heat and failure condition that followed.

The question is when, either soon after the outboard was shut down from 2nd run cycle over a month ago or as I attempted to start it this past Sunday??? Inquiring minds may never really know...LoL.

As you suggested Al, I have already checked water passages and flow through powerhead by back-flushing from thermostat block cavity and by also flushing with block flush port. I checked for any debris through cooling system before and during flush, none present. Exiting water flow was good through "tale-tale", block flush port, and brass up-feed tube. Water passage in lower unit have been thoroughly picked clean and flushed. Strangely enough the broken impeller veins accumulated just behind the plastic inlet screen/baffle of the lower unit.

Phil, thank you for the web link. I viewed this video and various others prior to the rebuild. Unfortunately the water pump assembly in the video is a bit different than on my 2007 Yamaha 90. The only 2 components that appear similar is the impeller and the plastic upper housing (but only in appearance). My upper housing does not use an o-ring for sealing, it utilizes a gasket and there is no o-ring used under my impeller assembly. I replaced the original wood-ruff key with a new unit from the rebuild kit. It is currently intact and with no visible damage. I may elect to re-use it.

I will certainly check and re-check every step of this second rebuild and I will mic the shaft diameter to compare with new impeller I.D. during purchase for irregularities.

Thanks to all who posted and for the suggestions...I will update after second rebuild and start-up.

Happy boating...
Angel M.

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Although I am unable to add anything more constructive than what has already been expressed by previous posters I am compelled to ask if other brands of outboard have a different and SUPERIOR water pump design.

Though few on this thread could be as inexperienced as I, the impeller replacement was easy....once I could get the lower unit off (1991 Yamaha 40hp).

My biggest gripe with the Yamaha design is the correct seating of the uptake tube (why not longer with a positive connection for something so crucial) and the absence of a mesh filter to prevent debris from clogging the water circulation channels in the upper block.....I am told this will kill the engine.

BTW, NOTE TO SELF: next impeller replacement, buy two impellers....one complete kit and one extra impeller.......it's cheap and reduces the stress of fiddling with a greasy impeller and sharp housing cup.

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Hello docsoma, after discovering the amount of salt contamination or crusting within the thermostat environment, I can only imagine what the unseen water passages might look like.

I have flushed as much as I can for now with lower unit having been removed but, I feel that (and also depending on salt water usage of vessel/motor) a chemical flush might be a good option a couple of time during the boating season. Products such as "Salt Away" and similiar and even a "Simple Green" degreaser mix with motor water flush with an appropriate dilution rate of course (10 to 1 ) ratio has been discussed on a few forums.

This was one reason why I purchased the outboard flush bag that I have mentioned during this thread.

I do not feel the pump/impeller assembly design is flawed, infact your's is much simpler than mine. My 2007 Yamaha 90 TLR 2-stroke uses more components than your 50, the issue is that there really isn't sufficient information available for the smaller assembly details. I purchased an official Yamaha manual almost specific to my motor and there is no details to impeller fittment concerns.

We live an learn I guess, I'm just really glad that I never had the opportunity to water test the boat since remounting the lower unit over a month ago. I may have certainly ruined the power head with the failure because the water test would have been intended to check for a "safe-mode" condition that presented itself back in August of last year and which I had posted a discussion thread on.

The August incident eventually uncovered (and after much testing and investigation by me and a boat repair center) that a water pressure/flow problem was developing, thus the cooling circuit overhaul. I would have never imagined this type of failure and at a W.O.T. condition. OUCH!!!

Happy boating to all...
Angel M.

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Hello to all and an update.

Rebuilt the impeller assembly this afternoon with all new parts from a local boat shop/Yamaha dealer.
I showed them the damaged parts and detailed the trouble I had with the impeller fitment.

The parts guy and one of the mechanics present were quite surprised with the damage. The mechanic's opinion is that the impeller sat high in it's location causing excessive friction with the stainless cup leading to the eventual failure.

The mechanic explained that the Yamaha 90 2 stroke impellers have a tendency to fit somewhat tight but not to the point that they most be forced into place as I had to. He recommends always lapping the shaft area with mild grit emory cloth/sandpaper to dress the diameter prior to install. Then a mild coating of grease or as he mentioned a good lubricant/penetrant such as "Corrosion X" to ease in sliding the impeller.

I mic'ed the shaft diameter before heading to the Yamaha dealer and measured the new impeller I.D. while there. The clearance diameter was good, I did a test fit once home and the new impeller fit perfectly into position and easily removable as well.

The input/drive shaft must be turned "clock-wise" to properly set the curve of the impeller veins which I did when setting the upper housing into place followed with tightening the 4 bolts down to 60 in. lbs.

Thermostat asembly is re-installed and I hope to start the outboard sometime tomorrow. I did encounter one hiccup during the lowerunit assembly the 8mm x 1.25 bolt that goes through the trim anode area up into the mid-section, during the torque sequence failed or fatigued when my torque wrench failed to register the appropriate setting. A bit of drilling and extracting and all is well again along with a newly purchased and installed bolt.

I will post the start up results, till then...
Angel M.

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Hello and good evening to all.

Wanted to update those that followed my impeller failure thread from a few days ago. I mentioned in a post Thursday evening that I had completed the second water pump rebuild. I started the Yamaha 90 yesterday afternoon with excellent results. I ran the motor in the 40 gallon flush bag and before start up I primed the cooling system through the block flush port for added measure.

I ran the motor intermittenly for 5 minutes with excellent water flow from the "tale-tale". Today I water tested the Dauntless. Through a good friend I was granted access to a substantially sized residential fresh water lake system in my immediate area.

I put the outboard through numerous (get on plane) W.O.T. scenerios with excellent results. From the numerous test runs I did today I can say that I have corrected two major issues that were plaguing my outboard.

The first was the original condition from August 2013 the "safe-mode" operation that could not be properly diagnosed even after various attempts. Eventually the culprit was the cooling circuit thus the complete water pump, thermostat assemblies, and temp sensor replacement. The lastest issue with the impeller failure which is now resolved has greatly educated me with impeller design and fitment.

I was also able to test (the new to me) "semi-cleaver" prop I had purchased some months back. Incredible stern lifting capabilities from this prop, the Dauntless jumps right on plane immediately with no effort or stuffing the stern.

The wife and I can't wait to get back out on the bay again and head to our favorite sand bars in the Biscayne National Park area's. Thanks again to all that follow and offered suggestion to my impeller thread.

Happy boating and Memorial Day holiday to all our Military families and friends still in harm's way.

Angel M.