Yamaha manual needed

[Bign0703]

Anyone have a sharable link to a yamaha manual for a 2004 f50 4 stroke carb motor?

 

[turbotodd]

I don't have a manual, but the thought of a carb F50 isn't a nice thought. Those have to be one of the worst, hardest carbs to have to clean (successfully). I hated them. But once "right", that motor absolutely purrs at low speeds!

Had a tiller version on a 548 War Eagle, briefly. Too much motor for the boat.

 

[MN Fisher]

Anyone have a sharable link to a yamaha manual for a 2004 f50 4 stroke carb motor?

I found the service manual for the 2000 F50 - maybe it'll help
https://www.manualslib.com/manual/909046/Yamaha-F50a.html

 

[Bign0703]

Thank you so much!!! And yes these are an absolute PAIN!!! IM FED UP WITH THEM!!!

 

[Pappy]

You realize you need a carburetor sync tool to get them set up correctly after cleaning. You can have the cleanest carburetors in the neighborhood and the engine will never run correctly if the throttle blades are not set correctly.

 

[turbotodd]

The jetting is staggered too. As I remember, pilot and main jets differ between cylinders. Also the prime start system only primes two of the four carbs. The passages in the bowls for the prime start tend to plug up, and they are no fun to get clean. If they aren't squeaky clean it'll be hard to start and it won't idle properly even when hot. Yamaha put out a bulletin for the F40 (3 carb/3 cyl and the 4 cyl/4 carb) and F50X that addressed the cleaning procedure, but they also suggested to replace the bowls on the prime start carbs rather than cleaning them.

gotta use a manometer to sync them too, along with the correct adapters for the intakes. And people wonder why they cost so much to do the job. I wouldn't do them for less than 3 hours labor. Most of the time it was a little closer to 4 hr by the time they were properly cleaned, sync'd and then test run.

 

[Bign0703]

Well I got them exceptionally cleaned. Pulled out my sync tool only to find it broken!!! (Haven't used it in a while) but i did get in the manual and found the factory setting of everything and went through and got it set up. Carbs are set to spec and tuned it +-50 rpm per carb as specified to do. Though I don't have the tool I've not really needed one in several years. Starts beautifully! Idles great! Revs great in water! With the hood off!?!?!?! Will run out good til half throttle then big out and die. I've never had one do this. If the hood is on its literally like the carbs are starving for air. With hood off it does great until about half throttle in gear. I mean this motor has been seriously neglected. Gas left in it for 9-11 months at a time while stored, no oil change, no anything in 10+ years. So to say complete nightmare is an understatement. But it's family of a friend of mine so trying to cut him a little slack. He just turned 18 and his grandfather gave him the boat but never did anything to it but try to run it a month or 2 a year.

 

[Bign0703]

The jetting is staggered too. As I remember, pilot and main jets differ between cylinders. Also the prime start system only primes two of the four carbs. The passages in the bowls for the prime start tend to plug up, and they are no fun to get clean. If they aren't squeaky clean it'll be hard to start and it won't idle properly even when hot. Yamaha put out a bulletin for the F40 (3 carb/3 cyl and the 4 cyl/4 carb) and F50X that addressed the cleaning procedure, but they also suggested to replace the bowls on the prime start carbs rather than cleaning them.

gotta use a manometer to sync them too, along with the correct adapters for the intakes. And people wonder why they cost so much to do the job. I wouldn't do them for less than 3 hours labor. Most of the time it was a little closer to 4 hr by the time they were properly cleaned, sync'd and then test run.

Manometer? Isn't that for fuel injected? I only knew of the vacuum sync tool and tach.

 

[Bign0703]

You realize you need a carburetor sync tool to get them set up correctly after cleaning. You can have the cleanest carburetors in the neighborhood and the engine will never run correctly if the throttle blades are not set correctly.

Yes sir pappy. Thankfully mine are broken! I haven't used them in years so after the move I guess I can't be too horribly mad. They were a cheap set I bought about 15 years ago. But new set on the way and she will hopefully be ready to go by the weekend

 

[wmk0002]

FWIW, I always go to the official Yamaha website and look up the factory service manual literature number then get on Ebay and search for it. Typically find them for about $20 in like new condition. I appreciate a digital copy but I like having the book with me in the shop or to read through when I can and keep my eyes off the computer screen, which I spend all day on for my day job.

 

[Pappy]

You realize you need a carburetor sync tool to get them set up correctly after cleaning. You can have the cleanest carburetors in the neighborhood and the engine will never run correctly if the throttle blades are not set correctly.

Yes sir pappy. Thankfully mine are broken! I haven't used them in years so after the move I guess I can't be too horribly mad. They were a cheap set I bought about 15 years ago. But new set on the way and she will hopefully be ready to go by the weekend

You must have been around the motorcycle world for a while then.........!

 

[Bign0703]

You realize you need a carburetor sync tool to get them set up correctly after cleaning. You can have the cleanest carburetors in the neighborhood and the engine will never run correctly if the throttle blades are not set correctly.

Yes sir pappy. Thankfully mine are broken! I haven't used them in years so after the move I guess I can't be too horribly mad. They were a cheap set I bought about 15 years ago. But new set on the way and she will hopefully be ready to go by the weekend

You must have been around the motorcycle world for a while then.........!

Haha you guessed it. Motorcycles and atvs until about 2007. Started when I was about 8 or 9 building my own lt230 Suzuki and yamaha blaster and took to it like a natural as my father told me. Quit them in high school and started messing with outboards more. But the ole merc tunes have almost always done the trick for me over the years. But I is a new age I suppose so I guess it's been time to adapt for awhile.

 

[turbotodd]

Double and triple check your part numbers & sizes for the jets, and make sure you have them in the right places.

yes, a motorcycle style manometer for carb sync is almost a requirement, as are the correct adapters that screw into the intake manifolds. It can be done without, but with, it idles even better. The F40/F50 4 cylinder motors are silky smooth-when set up right, at idle they are absolutely silent with the cowling on.

Speaking of cowling. A very common issue IS the cowling. I've seen more than one that had the air passages restricted by dirt dobber nests or whatever. Take the cowling off, flip it over, and remove the screws that hold the baffles on. See what you can find in it. I certainly hope that is where your issue lies. I pity the poor soul that has to do carb cleanings on these F40/F50 4 cyl motors. Worst set of carbs I've ever done in my 40 some years. So when you get it figured out, I'd highly suggest running ringfree plus fuel additive or at the least a good stabilizer, and start the motor about once a week to keep fuel circulated when you aren't using it. Makes a big difference. Maybe you won't have to clean the carbs again.

 

[Bign0703]

Double and triple check your part numbers & sizes for the jets, and make sure you have them in the right places.

yes, a motorcycle style manometer for carb sync is almost a requirement, as are the correct adapters that screw into the intake manifolds. It can be done without, but with, it idles even better. The F40/F50 4 cylinder motors are silky smooth-when set up right, at idle they are absolutely silent with the cowling on.

Speaking of cowling. A very common issue IS the cowling. I've seen more than one that had the air passages restricted by dirt dobber nests or whatever. Take the cowling off, flip it over, and remove the screws that hold the baffles on. See what you can find in it. I certainly hope that is where your issue lies. I pity the poor soul that has to do carb cleanings on these F40/F50 4 cyl motors. Worst set of carbs I've ever done in my 40 some years. So when you get it figured out, I'd highly suggest running ringfree plus fuel additive or at the least a good stabilizer, and start the motor about once a week to keep fuel circulated when you aren't using it. Makes a big difference. Maybe you won't have to clean the carbs again.

Sorry I'm so late! I finally got it finished! The man is going to end up needing 2 new carbs. They are completely corroded deep into the metal! I did suggest getting all 4 while he was there but only time will tell. However I did get it back to running for him, not the greatest, but it sure runs now! He was bound and determined to atleast get to crappie fish some before he decides to buy new carbs or a new motor. I will say this tho, without being able to pull vacuum I would have never been able to get it running at all! Swore I'd never touch another and now I got a mercury thats identical to it coming in next week! Majorly dread it but the new guy don't mind spending money when it needs it

 

[turbotodd]

So you got it running, then took it back apart? Maybe I misunderstood.

Still say a manometer is required...I've done them without, F40's and F50's both (LOTS of F40's both 3 and 4 cylinder) but using some sort of manometer to adjust each carb perfectly (+/- 2 inches of mercury) yields a much more professional job. One that you can be confident that won't return or have any running issue complaints. It makes a difference. I say this because in any repair you have to consider ALL of the possibilities. If it's not running is it fuel? Spark? Compression? Air? And, if one is found and you have it running, you have to also address the other three to eliminate those possibilities. Because if you don't check it over, and it returns a YEAR later, the customer has lost confidence in you, and you've lost confidence.... "Did I check that?".....

In 2011 a guy my dad used to work with brought me a 30 foot pontoon, with a Yamaha F100 carb engine on it. Like I had room to work on a 30 foot toon. Anyway, he'd had it at 4 other shops in the roughly 70 mile radius and said if you can fix this I'll make it worth your while. I dunked it in a test tank fired it up and it idled horrible. 4 cylinder 4 carb. I mean, terrible! Out of curiousity, I grabbed my old manometer (mercury filled...) and hooked it up. The carbs were so far out of whack it was a wonder it idled at all. One cylinder was at 20"/hg and another was at 2". You get the idea.

I also did ATV's and MC from 1989 til 2000, then they took on 2 brands of tractors, and stuck with 5 different brands at the same dealer until 2019. Dealer got bought out in 2017 by some investment place (corporate) and the GM and I did NOT get along, from day one and I said see ya! Started my own gig and semi-retired now but mostly done with outboards. I do not have room for boats at my little shop.

multi-cylinder/multi-carb motorcycles are very similar to multi-cyl/multi-carb outboards. You can get close but close doesn't cut it in my book.

EDIT: The 2009+Yamaha R1 is one of those weirdo's that you can't really sync the throttle bodies....they have a spec for them and it's not all +/- 2"/hg.

 

[Bign0703]

TurboTodd, yes I did remove them again to ensure jetting as you said. They were correct but his bottom 2 carbs were rough! I told him in the beginning and he insisted that i just get it running enough to use as he was debating repowering the boat instead of replacing the carbs on a super low hour motor. Heck I even offered to buy it but he still wasn't sure. Needless to say he is super young and I'm assuming doesn't want to come out much money. He is now having lower unit issues so I'm gonna say it will he on the market soon.

But as to the carbs I finally got it completely dialed in with the manometer and WOW!!! I never thought so little would make so much of a difference. It wasn't off much but the "accelerator pump" on the bottom carb was pretty far out of adjustment and later found he had adjusted on it some before bringing it to me. But he did get a few trips on it until the lower broke something.

Just got done with a mercury almost identical to it and went without a hitch! Had it done in 2 days and runs as good as new! But he didn't mind spending the money on the $100 a piece rebuild kits that it definitely needed.

I'll definitely be sticking with my old 2 stroke omc motors haha

 

[turbotodd]

you can keep your two strokes until you can't get no more parts for em

I'll keep my 4 stroke and enjoy the lack of fuel usage, quieter operation, and overall better experience.

I dug my old 25 2 stroke (3 cyl) out a while back and tossed it on, run it around the lake a little, and as soon as I got back home I pulled it off and put the 4 stroke back on. I forgot how crude that old thing is! Pickled and back in storage for another year; unless I decide I have to sell it for whatever reason.

 

[wmk0002]

I dug my old 25 2 stroke (3 cyl) out a while back and tossed it on, run it around the lake a little, and as soon as I got back home I pulled it off and put the 4 stroke back on. I forgot how crude that old thing is! Pickled and back in storage for another year; unless I decide I have to sell it for whatever reason.

Hit me up you ever want to sell it!

 

[turbotodd]

I dug my old 25 2 stroke (3 cyl) out a while back and tossed it on, run it around the lake a little, and as soon as I got back home I pulled it off and put the 4 stroke back on. I forgot how crude that old thing is! Pickled and back in storage for another year; unless I decide I have to sell it for whatever reason.

Hit me up you ever want to sell it!

i put you on the list.

 

[wmk0002]

I dug my old 25 2 stroke (3 cyl) out a while back and tossed it on, run it around the lake a little, and as soon as I got back home I pulled it off and put the 4 stroke back on. I forgot how crude that old thing is! Pickled and back in storage for another year; unless I decide I have to sell it for whatever reason.

Hit me up you ever want to sell it!

i put you on the list.

Probably a long list lol.