Impeller sharpening

[Seth]

How do I know if I have a stainless impeller? Also what size motors benefit from them? I've heard that 90 horse and up benefit and also heard that 150 and up are the only ones that benefit.

 

[Lil' Blue Rude]

Most pumps come stock with a zinc alloy impeller. The stainless have very thin blades. Stainless are also VERY HEAVY, at least 2lbs heavier than a zinc one. I'm going to guess a 6 7/8 stainless would be around 7-8lbs if not more than that. I know that the 6 1/8 are around 5lbs where a zinc one is 4 1/4lbs and a aluminium is 3 1/2lbs. The stainless are also very durable.
As for what size motors benifits it depends, my motor is a 40/28 evinrude that I've done a little work to and it gained me 1mph when I put a stainless 6 1/8 in.

 

[georgiaken]

It seems you guys have figured it out, but for clarification, the Snyder boats article says:

"It is important to create a clean edge within 1/32 of an inch. Do not to bevel the leading edge or create a double chisel point."

Chris wrote the article and also is in the Backwoods Angler video...

In other words, DON'T sharpen the blade from BOTH side...

 

[georgiaken]

Regarding polishing...I am no expert, but what I have read pretty much says:

Polishing will increase performance...until you ingest a small stone or sand and the polish job is ruined.
For the amount of time and effort required to polish the blade, the positive effects won't last very long...

 

[Lil' Blue Rude]

It seems you guys have figured it out, but for clarification, the Snyder boats article says:

"It is important to create a clean edge within 1/32 of an inch. Do not to bevel the leading edge or create a double chisel point."

Chris wrote the article and also is in the Backwoods Angler video...

In other words, DON'T sharpen the blade from BOTH side...

I know what the "experts" say about sharpening impellers but my knolege comes from first hand experience of sharpening diffrent impellers in diffrent ways and the methods that I stated early are the ones that I've had the best results with.

If Snyders method is the correct method of sharpening an impeller then you explain to me why a impeller that was sharpened in the method he explains is 3mph slower than the same impeller sharpened in the way I described. I would love to here how he came up with his method of sharpening impellers. We've been sharpening impellers like this for over 10 years now and every time I hear of someone sharpening an impeller like Snyder explains they have problems with their boats spining out when they take off. When they sharpen it like I described the problems stopped.
Sharpen how you want I'm just telling you what I've learn in my experience with outboard jets.
As for polishing your impellers it isn't a mod that will be felt in the seat of your pants, it's one of those list of small things that need to be compined to make a diffrence. Polishing the pump makes a bigger diffrnece then the polished impeller but it might not be noticble by the seat of your pants but it does help, it doesn't have to be polished to a mirror finish it just needs the casting smoothed down.

 

[moelkhuntr]

Just came in from sharpening my impeller the way Lil' Blue Rud has suggested. Trying to get things ready for next weekend when I go run with the big dogs. My little 60/40 E-TEC just ain't going to hang with those big dogs, But I will say I will have just as big a time getting there. Last I saw it was calling for halfway nice weather but in MO you just have to wait and see. See you'll Sat. if the sky doesn't fall.

 

[bulldog]

I sharpened my impeller yesterday the way lilbluerude described. My new deck makes my boat basically jump out to the water like I have never felt and after looking at my impeller when I got home it was not sharp and you could tell I had sucked some stuff up last year. I'm anxious to see if it makes a difference. I can't even tell you how careful I was to not even breath on the bottom edge of the impeller. :lol:

 

[georgiaken]

It seems you guys have figured it out, but for clarification, the Snyder boats article says:

"It is important to create a clean edge within 1/32 of an inch. Do not to bevel the leading edge or create a double chisel point."

Chris wrote the article and also is in the Backwoods Angler video...

In other words, DON'T sharpen the blade from BOTH side...

I know what the "experts" say about sharpening impellers but my knolege comes from first hand experience of sharpening diffrent impellers in diffrent ways and the methods that I stated early are the ones that I've had the best results with.

If Snyders method is the correct method of sharpening an impeller then you explain to me why a impeller that was sharpened in the method he explains is 3mph slower than the same impeller sharpened in the way I described. I would love to here how he came up with his method of sharpening impellers. We've been sharpening impellers like this for over 10 years now and every time I hear of someone sharpening an impeller like Snyder explains they have problems with their boats spining out when they take off. When they sharpen it like I described the problems stopped.
Sharpen how you want I'm just telling you what I've learn in my experience with outboard jets.
As for polishing your impellers it isn't a mod that will be felt in the seat of your pants, it's one of those list of small things that need to be compined to make a diffrence. Polishing the pump makes a bigger diffrnece then the polished impeller but it might not be noticble by the seat of your pants but it does help, it doesn't have to be polished to a mirror finish it just needs the casting smoothed down.

Well, I can't argue with experience...I've only owned my jet for 2 weeks and I've never had it in the water yet (as the pilot). I am just passing on things I picked up while doing my research. So, I won't even begin to make any argument to the contrary.

As for the polishing...if you have the time and the interest, it certainly won't hurt anything. It will make the jet more efficient for sure. It's just that sand and pebbles will find their way into our intake and will negate whatever we gain from polishing. I'm not saying it's a bad thing...just that you might ultimately waste your time. Polishing pre-fab parts that come off an assembly line will, in most cases, improve them...I polished my baitcasters and they definitely improved...but I don't have abrasives running through them, since it's easy to keep them clean.

I tend to be a perfectionist, so I certainly understand...

 

[Lil' Blue Rude]

Sorry if I came across too harsh. Sometimes you have those days ya know.

 

[fender66]

Good discussion guys. Really good info and some from different perspectives. Remember...you can't tell someone's tone from a post, and more importantly, we are all family here. The worst thing that should happen is we agree to disagree. No harm in that.:mrgreen:

I think all is good Lilrude.

Seems like this discussion is more directed towards "speed" performance. I'd be interested in fuel consumption performance. I'm guessing that none of this will help in that area though?

 

[georgiaken]

Sorry if I came across too harsh. Sometimes you have those days ya know.

No apologies necessary (but certainly appreciated). I didn't take your response as too harsh.

I figure, people are passionate about the things they care about and no one wants a fellow angler to be misinformed with BS.

So, I didn't take it badly at all...

It's actually good to know that I have some options...and I'll know what to do if I follow those instructions and end up with no juice out the bottom end.

Regarding speed and fuel economy, I tend to think along the lines of...if you want more speed (and your current rig is set up right), get a bigger motor. If you want better fuel economy, get a 4 stroke, one of the newer high tech 2 strokes or ease off the throttle. The little things we do to tweak stuff often works, but sometimes it's not worth the trouble...

 

[fender66]

Regarding speed and fuel economy, I tend to think along the lines of...if you want more speed (and your current rig is set up right), get a bigger motor. If you want better fuel economy, get a 4 stroke, one of the newer high tech 2 strokes or ease off the throttle. The little things we do to tweak stuff often works, but sometimes it's not worth the trouble...

I'm already running a 225 Merc.....no chance I'm getting anything bigger. It's bigger than I want already. :LOL2: Very seldom do I run WOT unless I'm messing around on my way back in on the river. Most of the lakes that I fish freak when I show up with my rig anyway, so I go pretty easy on those. It just sucks gas....and I'm used to it I guess....and I'm blessed to have it! Besides...I want to go fish way before I want to go fast.

 

[georgiaken]

There might be some folks out there who know how to "tune" an outboard for max output and better fuel economy...I don't doubt that.

My truck gets better gas mileage now than it did "new" and it's 15 years old.

It was a matter of upgrading my spark wires to racing wires, upgrading my spark plugs, cleaning EVERYTHING (engine top end, throttle body, intake) and changing over some of the fluids to higher end stuff (like Royal Purple). I got another 3mpg out of it all...over the long haul, it's paid itself off.

If we have folks who know how to do that with outboards, I am all ears

 

[optaylor823]

I agree with fender. I run a 175 and would love to see better gas mileage. It is hard to miss some of the rocks in the river I fish at 40 mph, so I usually don't run wide open. I may have missed this in the post, but I can say from experience that it does not matter how sharp you get the impeller if you do not shim it to the 1/32 gap.

 

[moelkhuntr]

Do they make any shims that are HALF the thickness or do you just shim it down where moving a shim to the top makes it hit. A person could get it down to the nitty gritty with shims half the thickness. Or, if a person is that dang close it's going to make that much difference.

 

[optaylor823]

I shim it as close as I can get to 1/32 and not closer. The impeller will have some wobble in it, so if you get to close it will hit and you do not want that.

 

[bulldog]

I have heard of people grinding the shim washers down to half the thickness but it sure would be nice if they made them that thin.

 

[Lil' Blue Rude]

Glad I didn't upset anyone, just read back over it and thought it could have been taken the wrong way.
Putting on exhaust,carbs(or re jeting carbs) and raising compression is the normal mod around here and most guys say they get better gas milage and perfomance from their set ups. It makes sense. If your boat runs better it's not laborig as hard so you don't use as much throttle getting around. Setting your boat up for speed is the best way to get better gas milage in my book, as long as you don't have a lead foot(or hand in this case) :mrgreen:
You don't want to get your impeller shimed down to for because they do tend to wable a little.

 

[Codeman]

I was going to pull my impeller and sharpen it before this weekend. I just checked, IT'S TOO FREAKIN' COLD OUT THERE. LOL Looks like it won't be coming apart before Saturday. She'll run what she runs. moelkhuntr if you are afraid of running way back of those big motors, just throttle back a bit and I'll catch up and keep you company. LOL

 

[moelkhuntr]

If the temp keeps dropping I may be running really slow as to not blow out the fire that I will have in a five gallon bucket to keep warm. HaHaHa. Started out to be 43 for Sat and it went down to 31 now it's up to 38 again I see. One thing about MO, give it five minutes and it will change for sure.