Fuel Pump Issues.-

Sea Rider

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A shade tree mechanic just rebuilt a Tohatsu 18 HP which owner flipped at sea. All bearings were replaced. The OB has only been tested on a barrel. Starts fine, but dies after some time. When primmed again starts right up and dies same. Disassembled fuel pump and internal diaphragm looks extremely warped and excessively balooned due to E8 fuel, have any of you experienced same as for fuel pump to pump near 0 fuel due to diaphragm being kaput ?

Yes I know, install a new diaphragm and voila, sorry no replacement for the moment, will need to be ordered, bad music...

Happy Boating
 

Baylinerchuck

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Jul 29, 2016
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Yep sure have. I have had several impulse type pumps that have gotten hard over the years. From my 1978 Johnson to older Echo power equipment Walbro carbs. It definitely occurs.
 

ondarvr

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You seem to like posting about fuel pump diaphragm’s and E-8
 

Sea Rider

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You seem to like posting about fuel pump diaphragm?s and E-8

Is there an issue with that ? I find amazing that you like to systematically contradict my E issues state of the art proven with precise pics that tells stories. Sorry, proven practice contradicts plain E theory. Next time you chime in on my posts, provide at least a proper answer, that's what the forums are for...

Bottom line, if you guys have 0 issues with E fuels receive my sincere congrats, We have horrible issues with them...

Happy Boating
 

ondarvr

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What I've said in the past is, if you see issues with E-8 in your country that we don't see in the US with our E-10, then something is either different about the fuel, or different about the parts being affected. My fuel pumps do not fail in a short period of time in any motor, even the oldest ones, they might get changes every 20 years or so, and that's only if needed, most are much older than that.

There are huge numbers of Tohastu built small motors in this country and fuel pump failures are not something you hear much about, as in almost never.

I've been using E-10, or at least some blend, for around 25 years.
 
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bruceb58

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Bottom line, if you guys have 0 issues with E fuels receive my sincere congrats, We have horrible issues with them...
No issues...you must have crap fuel down there.

Maybe switch to Yamaha engines.
 

Sea Rider

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Just asked if there could be pumping issues when thin diaphragms goes bad with use. Yes if excessively warped, deformed, balooned as a circus tent independently of the fuel used. Pumpiing work will be canceled.

Don't know why so much hanky panky going on everytime I mention E fuels. To each their own fuels and related issues. Period!!

Happy Boating
 

km1125

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Aug 10, 2016
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I am certainly no fan of E-fuels, especially when they can be advertised and sold as "regular gasoline"!! However, sometimes I wonder if they get blamed for problems in an engine when the real culprit might be other additives that someone put in the fuel in an attempt to 'fix' an issue. Methanol would be one of those, which is even more corrosive to aluminum than E-8 or E-10 (IF those "E's" are Ethanol-based!), especially if overdosed. Other additives might be just as bad or worse. Who knows what a previous owner might have done.

NOTE: This is NOT to address SeaRiders history with the engines he knows and has had apart which he likely has a much better history on.
 

ondarvr

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I am certainly no fan of E-fuels, especially when they can be advertised and sold as "regular gasoline"!! However, sometimes I wonder if they get blamed for problems in an engine when the real culprit might be other additives that someone put in the fuel in an attempt to 'fix' an issue. Methanol would be one of those, which is even more corrosive to aluminum than E-8 or E-10 (IF those "E's" are Ethanol-based!), especially if overdosed. Other additives might be just as bad or worse. Who knows what a previous owner might have done.

NOTE: This is NOT to address SeaRiders history with the engines he knows and has had apart which he likely has a much better history on.

I agree strongly with you.

People tend to overdose their motors with some products that can have a great deal of alcohol in them, Seafoam is one of them, and I've done it myself.

One method of removing carbon is to add a bunch of Seafoam to a gallon of gas and run it through your motor, I've tried it, it didn't have a noticeable negative affect on the outboards, but to get rid of the fuel I ran it in my mower, tiller and weed eater, the fuel lines on the tiller and weed eater instantly swelled up and broke, it took a while longer for the mower to do the same thing. It did clean all the gunk out of each one, and after replacing the fuel and vent lines they ran fine, but I imagine the fuel pump diaphragms were affected by it too.

On outboards the fuel lines and other rubber parts tend to be thicker and higher in quality, so it didn?t have the same immediate effect, but I?m sure they were to some extent.

In Sea Riders case I would say the ethanol content in the fuel they use may fluctuate at times, While it say?s 8% on the pump, it may be higher at times resulting damaged parts. The same thing happened in this country for a while. Or there could be a common fuel additive that people use that has a high E content.
 

Sea Rider

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Some precisions,

-Local fuels are pre mixed by gas Companies at their facilities with E8 content "by law" before being sold to gas stations, gas stations are constantly monitored without prior notice by an independent Company who checks E % content, fuel quality (impurities) and right amount of fuel per gallon sold at gas stations. Fines are severe...

- "Damage" means kapput, shot, dead. never said local E8 damaged Tohatsu's thin rubber diaphragms, only enlongates, balloons them faster than non E, if removed from internal fuel pump will not fit again, eventually a fuel pump will stop doing its homework right if severely ballooned.

-The only possible way for any OB not to form internal carbon build up on pistons, rings, cylinder head, exhaust port is using carbon inhibitors, cleaners added on fuel from day one immediately new OB is installed and on a regular basis use. On used 2 strokes OB which have never been treated with these products and already formed internal carbon buil up on these parts, these products won't do a thing. Carbon buil up will need to be removed mechanically once OB is dismantled.

Happy Boating
 

ondarvr

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Some precisions,

-Local fuels are pre mixed by gas Companies at their facilities with E8 content "by law" before being sold to gas stations, gas stations are constantly monitored without prior notice by an independent Company who checks E % content, fuel quality (impurities) and right amount of fuel per gallon sold at gas stations. Fines are severe...

- "Damage" means kapput, shot, dead. never said local E8 damaged Tohatsu's thin rubber diaphragms, only enlongates, balloons them faster than non E, if removed from internal fuel pump will not fit again, eventually a fuel pump will stop doing its homework right if severely ballooned.

-The only possible way for any OB not to form internal carbon build up on pistons, rings, cylinder head, exhaust port is using carbon inhibitors, cleaners added on fuel from day one immediately new OB is installed and on a regular basis use. On used 2 strokes OB which have never been treated with these products and already formed internal carbon buil up on these parts, these products won't do a thing. Carbon buil up will need to be removed mechanically once OB is dismantled.

Happy Boating




Fuels are blended and monitored here in the same way, the E content can still fluctuate though, and at one time it was a problem.

“"Damaged”'' doesn't mean it's kapput, shot or dead. If your car gets a dent in it it's damaged, it still works though.

If all 2 stroke outboards in your area build up carbon that fast and need to run a de-carb product all the time, then again, something is different in your country when compared to here. Many de-carb products contain alcohol, so adding it increases the likelihood of raising the E content too high.
 

Sea Rider

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Won't keep arguing with you, both boat on different world conditions, so will end this post right here as you always like to have the last 100% proven knowledge of cause, don't you...

Happy Boating
 
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ondarvr

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I think you misunderstand the difference between discussing something and arguing about it. My intension is to understand, or at least come up with some reasons why you experience something different than what we see here.


I'm sorry if you feel like you're being attacked, that's not my intension.
 
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