Thermostat housing hole.

Douglasdzaster

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Can soak each carb with their needle seat in place, should soften any formed gunk if ever formed there. As the motor idles good, the idea is to put back all 3 Pilot's Screws at the same height position found defore being disassembled. If the carbs are not that gunked can soak the carbs in lacquer thinner for say 15 minutes and soon after squirt any Carb Cleaner Spray on each possible hole specially the tiny ones.

Happy Boating
I opened up a can of worms today. Pulled the carburetors and got started. The top carburetor which didn’t leak near like the other two. When I opened it up that bad gas smell hit me. I had no idea there were that many places for it to hide and just sit in the carburetors. The needle and float looked brand new but you can see by the pics ethanol was working. Both o rings cracking and jets had some blockage. It looked like someone tried removing the jets in all the carburetors because most where almost stripped. Someone put in new floats and needles and that was all. Middle carburetor I could not get the main jet out because it was scared when I started and made it worse. I hope you have a trick or two for it. Ethanol crust and gunk there as well. Other jet clogged. Third carburetor (the one leaking the worst. I turned it over to remove the float chamber and it’s missing a screw. Only had three the fourth hole has no threads left. So both top and bottom o rings are cracking on all three . All the jets looked pretty bad to me and if not clogged have blockage. Look at the seats and see if it don’t look like someone tried removing them with the wrong socket. Oh number three pilot screw is a little blunt on the end. I don’t see how it ran as good as it did with everything I found today. All I can say is go Yamaha. Sorry my report is so long. I would appreciate any thoughts on me removing that jet and about the missing screw. I thought maybe a self tapping.
 

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Douglasdzaster

Petty Officer 1st Class
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Messages
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I opened up a can of worms today. Pulled the carburetors and got started. The top carburetor which didn’t leak near like the other two. When I opened it up that bad gas smell hit me. I had no idea there were that many places for it to hide and just sit in the carburetors. The needle and float looked brand new but you can see by the pics ethanol was working. Both o rings cracking and jets had some blockage. It looked like someone tried removing the jets in all the carburetors because most where almost stripped. Someone put in new floats and needles and that was all. Middle carburetor I could not get the main jet out because it was scared when I started and made it worse. I hope you have a trick or two for it. Ethanol crust and gunk there as well. Other jet clogged. Third carburetor (the one leaking the worst. I turned it over to remove the float chamber and it’s missing a screw. Only had three the fourth hole has no threads left. So both top and bottom o rings are cracking on all three . All the jets looked pretty bad to me and if not clogged have blockage. Look at the seats and see if it don’t look like someone tried removing them with the wrong socket. Oh number three pilot screw is a little blunt on the end. I don’t see how it ran as good as it did with everything I found today. All I can say is go Yamaha. Sorry my report is so long. I would appreciate any thoughts on me removing that jet and about the missing screw. I thought maybe a self tapping.
Sorry I was so busy with a rant. Will it hurt to soak the jets or should I blow them out with cleaner and air and then polish?
 

Douglasdzaster

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Sorry I was so busy with a rant. Will it hurt to soak the jets or should I blow them out with cleaner and air and then polish?
Good morning im headed back out to the shop to clean and micro polish everything so I’m ready for the new gaskets when they arrive. I have a screw extraction kit I’m thinking about for that jet. I’ll be hitting it with some spray all day while working on the other parts before I do anything. I heard acetone and ATF 50/50 makes a good thread buster. Would it harm the carburetor or nozzle under the jet? I can replace the jet but can’t find the nozzle available.
 

Sea Rider

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As you have witnessed a carb exterior in mint clean cond doesn't say much, carbs could be real Pandora ones when opening them up. If all float's needles seats are just bit gunked, not scratched, check that with a flash light just micro polish them. Have never changed a single one and don't plan going that way any time soon LOL!!

Thinner doesn't harm carbs nor carb parts whatsoever been using for years now. With respect to the jets, main nozzle can soak them up with thinner for say one hour then poke the holes with a wooden tooth pick as to open them if bit closed and flush them well squirting repetitive shots of carb spray with the provided red cannula. Soak the upper carb in thinner for some hours and check if the faulty jet/jets comes out easily with whatever tool there's available at the shop. For the shade tree mechanic to have screwed the jet head in such a way must have found it really seized up on the thread. Take your time on the carbs....

Happy Boating


 

Douglasdzaster

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Messages
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As you have witnessed a carb exterior in mint clean cond doesn't say much, carbs could be real Pandora ones when opening them up. If all float's needles seats are just bit gunked, not scratched, check that with a flash light just micro polish them. Have never changed a single one and don't plan going that way any time soon LOL!!

Thinner doesn't harm carbs nor carb parts whatsoever been using for years now. With respect to the jets, main nozzle can soak them up with thinner for say one hour then poke the holes with a wooden tooth pick as to open them if bit closed and flush them well squirting repetitive shots of carb spray with the provided red cannula. Soak the upper carb in thinner for some hours and check if the faulty jet/jets comes out easily with whatever tool there's available at the shop. For the shade tree mechanic to have screwed the jet head in such a way must have found it really seized up on the thread. Take your time on the carbs....

Happy Boating


Yes sir. I think water wicked into the threads maybe. One squeaked the whole way out while unscrewing. Lol What are your thoughts on the missing screw from the bowl? Someone stripped the threads out completely.
 

Sea Rider

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Yes sir. I think water wicked into the threads maybe. One squeaked the whole way out while unscrewing. Lol What are your thoughts on the missing screw from the bowl? Someone stripped the threads out completely.
With respect to the missing bowl's screw will need to order a new one, is the thread a closed or open type in wich can screw a larger screw to exit the other side and secure with a nut ?

Have you managed to remove already the jet with screwed head, under it lays a nozzle which should be looked at, probably heavily gunked and discolored. Assume that's the ony one with issues and have already removed the other 2, right ? If possible post a pic of the stripped carb's thread to have a look...

Happy Boating
 

Douglasdzaster

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Messages
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With respect to the missing bowl's screw will need to order a new one, is the thread a closed or open type in wich can screw a larger screw to exit the other side and secure with a nut ?

Have you managed to remove already the jet with screwed head, under it lays a nozzle which should be looked at, probably heavily gunked and discolored. Assume that's the ony one with issues and have already removed the other 2, right ? If possible post a pic of the stripped carb's thread to have a look...

Happy Boating
I think I can put a screw with a nut in that spot. I’ll look and make sure. I just came in for a break. Been working on the first carburetor polishing the seat with tooth paste. They’re pretty bad so it’s taking a while. I can see the difference between it and the others now. They’re almost pin holes. Very discolored. Same for the jets and nozzles. I haven’t done anything with the screwed up jet. Scared of messing up and game over for that carburetor. I may take it to the guy that removed the thermostat bolt for me. I really appreciate all your help and telling me how to clean this stuff up. Saving me a lot of money. I don’t think those needles where sealing now that I see what the seat is supposed to look like. I’ll post some comparison pictures and also the threads on the jets. There’s stuff caked up in the tube where the small jets go with the cap on it. I gotta figure out how to get that cleaned up as well.
 
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Douglasdzaster

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A few pics
 

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Sea Rider

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When the needle's seats were brand new were shinny, toothpaste restores them to that cond. How long will need to micro polish them will depend entirely in the current condition found. If possible take the first carb to a machine shop and have that screwed jet be removed, install a new one. First carb internal parts looks in a bad shape.

Would advice to clean the cavity where the nozzle rest inside the carb, for that will need a longer wooden stick, what are you currently using to micro polish the needle's seats ? Usually clean and micro polish internal carb parts with this cheap wooden poker set once converted to wooden Q tips..

Happy Boating


 

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Douglasdzaster

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When the needle's seats were brand new were shinny, toothpaste restores them to that cond. How long will need to micro polish them will depend entirely in the current condition found. If possible take the first carb to a machine shop and have that screwed jet be removed, install a new one. First carb internal parts looks in a bad shape.

Would advice to clean the cavity where the nozzle rest inside the carb, for that will need a longer wooden stick, what are you currently using to micro polish the needle's seats ? Usually clean and micro polish internal carb parts with this cheap wooden poker set once converted to wooden Q tips..

Happy Boating


I’m using wooden skewer and cotton to make a big q tip and toothpaste. I just ordered a carburetor cleaning kit with nylon brushes. Will be here tomorrow or should I stick to the skewers at least where the nozzle cavities are? Will polish the nozzles and and jets with toothpaste. Don’t know what I’ll use for that yet. I’ll start off trying a rag with toothpaste.Couldn’t work on it today. I’m going to the machine shop Monday. Hope he gets it out without damaging the nozzle. Can’t get them anywhere but eBay about $80 after shipping. The float bowels have a chamber in the front that does not drain when you remove the drain screws. Found water in those and they looked the worst. Im so glad I have good access to non ethanol fuel for it after this.
 

Sea Rider

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Tips for cleaning external/internal carb's parts. If need to micro polish the external slow jet, pilot's screw tips and threads pic (1) Dampen with water a flat cotton piece, place jet inside, add toothpaste, close cotton to form a U shape, grab tight the cotton against the jet, insert a screwdriver to other side, both jet's groove and screwdriver's flat head must match same width. Twist the screwdriver back and forth several times while adding more toothpaste until shinny. To clean the interior, pass a thin needle, grab one side and spin the jet with fingers several rounds as in (3)

For nozzle polishing (3) hold tight nozzle ends, with a wooden cotton swab like moistened in water and added toothpaste rub the entire nozzle body sidewise, rotate it and keep polishing till shinny. Both ends must be immaculate clean. To clean the mini holes, a wooden toothpick tip rotated inside such holes will do the cleaning trick. If the nozzle is severely crusted soak it it in thinner for some hours prior poking the toothpick. Clean the interior with any wooden skewer that fits inside by rubbing it up-down against the internal wall. Wooden skewers, toothpicks will not scratch nor enlarge any hole whatsoever.

Will suggest to inspect the Pilot's Screw and the Nozzle cavities with a flaslight, if found dirty, gunked, roll a thin cotton layer dampened with thinner onto a wooden skewer and clean in circular motion the internal cavities and their threads. The rolled cotton portion must be taller than both cavity depths. (4)

Note : The cotton rolled whether CW-CCW onto the skewer must match the same CW-CCW circular motion cleaning inside each cavity, if not risk the cotton being disengaged from the skewer and be left inside the cavity which has occurred.

Some boaters following the thread will be wondering why a carb kit isn't used to avoid all the trouble and time consuming cleaning jets, nozzles. Will be much time/cost effective if being a one carbed motor, but that's a 3 carbed motor and at $85 per kit will end spending $ 255 bucks which can be used for other purposes.

A Dremel rotating tool along these polishing cotton felts (5) will do the micro polishing job way faster....

Happy Boating
 

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Douglasdzaster

Petty Officer 1st Class
Joined
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Messages
315
Tips for cleaning external/internal carb's parts. If need to micro polish the external slow jet, pilot's screw tips and threads pic (1) Dampen with water a flat cotton piece, place jet inside, add toothpaste, close cotton to form a U shape, grab tight the cotton against the jet, insert a screwdriver to other side, both jet's groove and screwdriver's flat head must match same width. Twist the screwdriver back and forth several times while adding more toothpaste until shinny. To clean the interior, pass a thin needle, grab one side and spin the jet with fingers several rounds as in (3)

For nozzle polishing (3) hold tight nozzle ends, with a wooden cotton swab like moistened in water and added toothpaste rub the entire nozzle body sidewise, rotate it and keep polishing till shinny. Both ends must be immaculate clean. To clean the mini holes, a wooden toothpick tip rotated inside such holes will do the cleaning trick. If the nozzle is severely crusted soak it it in thinner for some hours prior poking the toothpick. Clean the interior with any wooden skewer that fits inside by rubbing it up-down against the internal wall. Wooden skewers, toothpicks will not scratch nor enlarge any hole whatsoever.

Will suggest to inspect the Pilot's Screw and the Nozzle cavities with a flaslight, if found dirty, gunked, roll a thin cotton layer dampened with thinner onto a wooden skewer and clean in circular motion the internal cavities and their threads. The rolled cotton portion must be taller than both cavity depths. (4)

Note : The cotton rolled whether CW-CCW onto the skewer must match the same CW-CCW circular motion cleaning inside each cavity, if not risk the cotton being disengaged from the skewer and be left inside the cavity which has occurred.

Some boaters following the thread will be wondering why a carb kit isn't used to avoid all the trouble and time consuming cleaning jets, nozzles. Will be much time/cost effective if being a one carbed motor, but that's a 3 carbed motor and at $85 per kit will end spending $ 255 bucks which can be used for other purposes.

A Dremel rotating tool along these polishing cotton felts (5) will do the micro polishing job way faster....

Happy Boating
Thank you,thank you. The kits don’t come with any jets except the pilot and the nozzles are not even available anywhere for this motor. Besides there was a kit put in it about a year before I got it. Pilot jet,float and needle still look new. Its abvious it was not taken apart and cleaned correctly though. I took another look and the cavity that can’t be drained with the drain screw in the float chamber I described earlier is surrounded by the bottom o ring. So being that’s where I only found water . The o rings failed and it catches the bad stuff. Pic is before finish cleaning.
 

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Douglasdzaster

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Thank you,thank you. The kits don’t come with any jets except the pilot and the nozzles are not even available anywhere for this motor. Besides there was a kit put in it about a year before I got it. Pilot jet,float and needle still look new. Its abvious it was not taken apart and cleaned correctly though. I took another look and the cavity that can’t be drained with the drain screw in the float chamber I described earlier is surrounded by the bottom o ring. So being that’s where I only found water . The o rings failed and it catches the bad stuff. Pic is before finish cleaning.
Just found out Yamaha has discontinued the jet with the screwed up head. I can leave it and hope for the best or try the next bigger size which means I may have to replace all three ( not in my budget right now). Since the motor ran good but leaked fuel . I’m considering leaving it for now and cleaning up and polishing the rest . The needle seats look the worst and I’m polishing those.
 

Sea Rider

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12,345
You're welcome, Will check the screwed jet if available at a different parts source.

What you can do when all 3 carbs have finally been cleaned to perfection is to run the carbs dry if the motor won't be used contantly. Disconnect the motor's fuel connector and let the motor die of fuel starvation, can take advantage before the motor dies to flush the motor at fast idle for at least 5 minutes with fresh water.

Running carb dry avoids gunk formations inside carbs when sitting with fuel resting on them for long time periods. Cleaning carbs to a spotless condition it's a time demanding long procedure done once, that's why my 3 motors are one carbed ones LOL!!

Have you been adding additives to the fuel tank as to prevent or remove carbon build ups on your motor. If not a quick decarbon process will be good doing before the motor is put back into full open water operation, if interested let me know before the carb's air silencer is installed on them.

Happy Boating
 
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Douglasdzaster

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Messages
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Just found out Yamaha has discontinued the jet with the screwed up head. I can leave it and hope for the best or try the next bigger size which probably means I may have to replace all three ( not in my budget right now). Since the motor ran good but leaked fuel . I’m considering leaving it for now as much as I hate to and cleaning up and polishing the rest . Just wish I could get to that nozzle. The needle seats look the worst and I’m polishing those.
 

Douglasdzaster

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Messages
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You're welcome, Will check the screwed jet if available at a different parts source.

What you can do when all 3 carbs have finally been cleaned to perfection is to run the carbs dry if the motor won't be used contantly. Disconnect the motor's fuel connector and let the motor die of fuel starvation, can take advantage before the motor dies to flush the motor at fast idle for at least 5 minutes with fresh water.

Running carb dry avoids gunk formations inside carbs when sitting with fuel resting on them for long time periods. Cleaning carbs to a spotless condition it's a time demanding long procedure done once, that's why my 3 motors are one carbed ones LOL!!

Have you been adding additives to the fuel tank as to prevent or remove carbon build ups on your motor. If not a quick decarbon process will be good doing before the motor is put back into full open water operation, if interested let me know before the carb's air silencer is installed on them.

Happy Boating
Been using Seafoam and also did their decarb method. Most of the jets are open just looking bad and discolored. Even the ones with gunk in the tube and bowl . Nothing is used but non ethanol fuel as well since I’ve had it. Sorry for the double post back there.
 
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Sea Rider

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Not an issue if the big jets are discolored as long the internal holes are perfectly clean, can check that up with a magnifying glass or while holding the jets against a light source. The screwed jet is available, need to know the stamped number on it ?

Have you checked if it's possible to remove the screwed jet at a machine shop. If so and depending on the number can buy a spare new jet for around $ 14.00 + shipping. The nozzle located under the jet will surely look in a bad state, will need to be removed to clean it as the other 2.

Happy Boating
 

Douglasdzaster

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Messages
315
Not an issue if the big jets are discolored as long the internal holes are perfectly clean, can check that up with a magnifying glass or while holding the jets against a light source. The screwed jet is available, need to know the stamped number on it ?

Have you checked if it's possible to remove the screwed jet at a machine shop. If so and depending on the number can buy a spare new jet for around $ 14.00 + shipping. The nozzle located under the jet will surely look in a bad state, will need to be removed to clean it as the other 2.

Happy Boating
I just came in. I’ll look at one of the other jets for that number. Got the top carburetor ready( the easy one) except for waiting on the new o rings. The float is sitting lower than it was when taken apart. I don’t have the specs but I measured them before removal. How do I adjust? The screw is all the way down but didn’t raise it to where it was. I did bow through the fuel inlet with them right side up and air past through. Then turned it over upside down and blew and no air came out so I know it’s sealing.
 
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Sea Rider

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Is the float fixed or with an attached metal hinge ? Assume now that the seat is immaculte clean the float will rests slight under than used to sit at.

When the carb is turned upside down the float must sit at the same horizontal level to the carb's bowl square edge unless factory stated differently in the Yam's Service Manual which don't have.

Which carb 1-2-3 has the screwed jet ? The middle carb should have a slight larger jet numbert than 1-3 carbs, check that out.

Happy Boating
 

Douglasdzaster

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Is the float fixed or with an attached metal hinge ? Assume now that the seat is immaculte clean the float will rests slight under than used to sit at.

When the carb is turned upside down the float must sit at the same horizontal level to the carb's bowl square edge unless factory stated differently in the Yam's Service Manual which don't have.

Which carb 1-2-3 has the screwed jet ? The middle carb should have a slight larger jet numbert than 1-3 carbs, check that out.

Happy Boating
Sounds like the float is about right then. I guess cleaning that seat gave it room to sit lower. I’ll look at it again and get a picture . Carburetor 2 has the screwed jet. I’ll get that number. Been freezing out the last few mornings and I got honey do’s as well but I’ll be out there soon. Have not gone by the machine shop yet. Want to make real sure the jet can be replaced. Took carburetor 3 to the hardware store yesterday and got a screw and nut that should work in place of the stripped threads . Just got to open the bottom of the hole a little bit. The manual I found and downloaded had my model number included but it only covers a 2 cylinder 40 hp and the carburetors are different so they got me on that one.
 
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