Rodbolt and Yamaha Prime Start - Awesome

[Loggerhead52]

Hey Rodbolt,
I performed a search on the subject and quickly discovered that your knowledge of the Yamaha Prime Start system goes way beyond the scope of the average owner to comprehend and even beyond most trained technicians so I commend you and appreciate your willingness to explain what many of us just scratch our heads over. As a result of the explanation you included in several of your past posts, I am now convinced that my "stubborn cold starting" problem is with the Prime Start. I consider myself to be somewhat above average when it comes down to the care and maintenance of my outboard motors so when I have a problem, I've already eliminated the typical and obvious and have moved on to the more technical. Unfortunately, I do not have a service manual to refer to so like many others, I'm on here asking the same questions that you've probably rolled your eyes at a dozen times and I apologize for that but appreciate your patience. First, should the owners of "Prime Start" equipped Yamaha outboards be able to hear any sign of a clicking, whirring, hissing or any sound at all to indicate that the "Prime Start" solonoid is working when the key switch is turned on or is the internal rod movement within the solonoid too insignificant to make noise? Second, to your knowledge, is the solonoid "fuse protected"? I'm assuming that it operates at a full 12 volts so I need to check and make sure that current is available to the solonoid before I move into the dissasembly stage. I guess my third and final question would address the R&R and service procedure for the "Prime Start". If it needs to be done, is it simple enough to do without the assistance of a service manual? Thanks so much for your help!

Gary

 

[triumphrick]

Re: Rodbolt and Yamaha Prime Start - Awesome

Hey Rodbolt,
I performed a search on the subject and quickly discovered that your knowledge of the Yamaha Prime Start system goes way beyond the scope of the average owner to comprehend and even beyond most trained technicians so I commend you and appreciate your willingness to explain what many of us just scratch our heads over. As a result of the explanation you included in several of your past posts, I am now convinced that my "stubborn cold starting" problem is with the Prime Start. I consider myself to be somewhat above average when it comes down to the care and maintenance of my outboard motors so when I have a problem, I've already eliminated the typical and obvious and have moved on to the more technical. Unfortunately, I do not have a service manual to refer to so like many others, I'm on here asking the same questions that you've probably rolled your eyes at a dozen times and I apologize for that but appreciate your patience. First, should the owners of "Prime Start" equipped Yamaha outboards be able to hear any sign of a clicking, whirring, hissing or any sound at all to indicate that the "Prime Start" solonoid is working when the key switch is turned on or is the internal rod movement within the solonoid too insignificant to make noise? Second, to your knowledge, is the solonoid "fuse protected"? I'm assuming that it operates at a full 12 volts so I need to check and make sure that current is available to the solonoid before I move into the dissasembly stage. I guess my third and final question would address the R&R and service procedure for the "Prime Start". If it needs to be done, is it simple enough to do without the assistance of a service manual? Thanks so much for your help!

Gary

GARY...Get a service manual!!!!!

You can order them form most anywhere, find them on ebay, get them within a day and then you can learn about all kinds of significant as well as insignificant things about your motor!!

 

[Loggerhead52]

Re: Rodbolt and Yamaha Prime Start - Awesome

Why order a manual when I can interogate the service tech!!!???... I'm kidding of course!!! and I know I know!!!...That's usually the first thing I purchase but I neglected to order it for this one...nobody to blame but myself but I really hadn't planned on keeping this rig...it was a bank repo that I had planned on turning but I ended up liking it too much to part with.:redface:

 

[Dunaruna]

Re: Rodbolt and Yamaha Prime Start - Awesome

Why order a manual when I can interogate the service tech!!!???...

This could get ugly, I hope he has had his morning coffee before he sees this...................

 

[rodbolt]

Re: Rodbolt and Yamaha Prime Start - Awesome

morning coffee or evening beer.
cant recall what motor we were disscussing so its a moot point.
according to the tuneup spec guide even EFI motors are prime-start motors so depending on the model yes you may hear whirring or clicking.
some prime start models use the lighting coil for a voltage source,some use 12V and some use the ecu and its sensor inputs.
that outta about cover it.
but I dont mind usually, just be aware some folks say I can be acebric ,even abrasive.
dont ask a question if you dont want an opinion.

 

[Loggerhead52]

Re: Rodbolt and Yamaha Prime Start - Awesome

Well I try not to be overbearing when I ask for help but by all means, be as blunt as you need to be and don't hold back on the opinion on my behalf 'um, you had that beer yet Rodbolt? O.K, I pulled the G3 out of the garage and into the 65 degree north Florida climate when I got home from work. I hooked up the old flushing attachment, pumped the primer bulb and turned the key switch to the "on" (run) position and didn't hear a peep out of the prime start solonoid. Now, that is assuming it is supposed to get its power in the "on" position and not the "start" position otherwise, I wouldn't be able to hear anything over the spinning starter. Anyway, I attempted approximately three 5 second to 10 second starting engagements to no avail. I flipped the red emergency starter valve lever to the "on" position and gave it another attempt. The 50 fired right up like it was suppposed to and after about ten seconds, I flipped the lever back to "closed" and let it idle for awhile. I guess my next step will be to check for current to the solonoid and make sure it's getting power. If power is available then the solonoid rod should activate and make noise right? If not, then the next step would be what, remove it and inspect it to see if there is something preventing it from activating? Hopefully, the solonoid is O.K. since it lists for $127.51

 

[rodbolt]

Re: Rodbolt and Yamaha Prime Start - Awesome

its not a solinoid and wont click ever.
its a thermal valve that uses a wax pellet heated by current,on your 50, from the stator lighting coil so no key on power.
it can be tested by removing and hooking the leads to a 12V battery making measurements both hot and cold and comparing them to the service manual.

 

[triumphrick]

Re: Rodbolt and Yamaha Prime Start - Awesome

it can be tested by removing and hooking the leads to a 12V battery making measurements both hot and cold and comparing them to the SERVICE MANUAL.

YES!!!!

 

[Loggerhead52]

Re: Rodbolt and Yamaha Prime Start - Awesome

I see it...repeat after me...SERVICE MANUAL!!!...Ugh!...I WILL get one as soon as the fish quit biting!...PROMISE!!! I just came in from checking current with a test light and since it isn't supposed to get current with the key switch in the run position, I'm assuming that the stator should send voltage during the cranking procedure (starter engaged) but I'm not getting any current to the "thermal valve" at any time. No one has tampered with the wiring on this motor but in attempting to trace it to the supply source, I lose it behind the starter mounting bracket and can't pick it up again beyond that. Drat!...Maybe I'll have time to stop by the Yamaha dealer tomorrow and see if I can look at a wiring diagram...maybe I can pick up one of those SERVICE MANUAL's while I'm there... Thanks guys.

 

[CatTwentyTwo]

Re: Rodbolt and Yamaha Prime Start - Awesome

My only experience with the thermal valve was on a 95 9.9 Yamaha, so take this for what it is worth. I think that you are getting confused between the solenoid and thermal type enrichment systems. The solenoid type would have power on it and enrich the mixture if you push in on the key. On a cold motor, the thermal valve type should already be in the enriched position without any power to it. After the motor starts, voltage is applied to the valve and the needle will begin to extend and close off the enrichment circuit after a minute or two. On my 95 motor, the thermal valve only had power on it when the motor was running. I would not be looking for an electrical problem unless the motor was starting but never coming out of the enriched mode.

 

[Loggerhead52]

Re: Rodbolt and Yamaha Prime Start - Awesome

I'm sure I sounded confused in my explanation by callng the thermal valve a solonoid and I apologize however I am familiar enough with the Prime Start system to know that although my key switch does push in, the act of doing so serves no purpose in my case since my choke system is not accomplished with butterfly plates. Thanks to this forum and the generous folks who are willing to share their knowledge, my understanding of how the Prime Start system works is expanding. So if my the thermal valve is supposed to be in the enriched position when the engine is cold, it should fire off quickly but as the engine begins to warm up, failure of the thermal valve to close off the enrichment circuit should cause the engine to load up or run rich. Well Hmmmmmm O.K., I have to flip the red manual switch to the "open" position which allows the enrichment to be accomplished and then I flip it to "closed" after a few seconds which closes off the enrichment passage and allows the correct air/fuel mixture to enter the engine. All of this said, the thermal valve is supposed to perform the same task automatically as power is applied when the engine is running...O.K., now I can visualize how it works and it simply sounnds like I need to remove it and test it as Rodbolt suggested. Thanks for clarifying ryoung...dang...that makes perfect sense...it doesn't need the power to actvate the enrichment...it needs it to turn it off...geez...I need that dang SERVICE MANUAL!!! Thanks for your patience all!

 

[rodbolt]

Re: Rodbolt and Yamaha Prime Start - Awesome

now I am gonna toss another prime start curve ball at ya.
the thermal valve wont "turn off" unless the engine stops or the lighting coil goes bad.
second is there is a small fuel pump located behind the cover that the red tag is on that supplies fuel under pressure to the system on that 50.
all of it has to work correctly or the automatic enrichment system simply wont work.
thats why it works manually.
ya gotta find what broke or is out of adjustment and fix it.

 

[Loggerhead52]

Re: Rodbolt and Yamaha Prime Start - Awesome

Here's the latest. I had to go into Gainesville today and while I was there, I stopped in at the Yamaha dealer hoping to speak with a technician. Well as I expected, I was pretty much blown off by a guy who I think was the owner and he basically just told me I needed to bring it in so they could go through the carburetors in exchange for my first born child...I thanked him and went on my way. Anyway, I removed the thermal valve and put 12 volts to it just to see how much the rod extended which was roughly about 1/8". I know I need a SERVICE MANUAL to know exactly how much it's supposed to move but I mainly wanted to see how it reacted to the current. Next, I disassembled the entire "fuel pump" that you described above Rodbolt and found absolutely nothing suspicious. There was no trash, no gum deposits, and no corrosion, just clean fresh fuel. In fact, it was soooooo clean in there that it appeared as if it had never been run. The fact that it was in this conditon served to reinforce the 20 hours of use that the broker stated was on it when I purchased the . I went ahead and shot air through the passages, checked the diaphragm for cracking and holes and then reassembled everything. I re-set the red emergency lever in the "normal" position and will see what it does first thing tomorrow morning. I doubt that what I did changed anything however...stay tuned for the outcome.if this didn't do anything to help, are the adjustments that you speak of too hard to tackle without a SERVICE MANUAL Rodbolt?

 

[Dunaruna]

Re: Rodbolt and Yamaha Prime Start - Awesome

The gaskets and diaphragm are o/k? Circuits clear?

 

[Loggerhead52]

Re: Rodbolt and Yamaha Prime Start - Awesome

I have that diagram and as far as I could tell, the passages were clear but I shot air through them anyway...I'm headed out to try it now.

 

[Loggerhead52]

Re: Rodbolt and Yamaha Prime Start - Awesome

Nothing like the sweet smell of success!...I hit the starter once for about 5 seconds...nothing...hit it again for another 5 seconds and she fired right up and ran for about 10 seconds and died once but fired right back up and ran at a high idle and slowly came down to a low idle... Thanks Rodbolt and all who helped me with this problem...obviously the shots of air through the passage ways cleared something out of the way 'cause I couldn't see anything physically wrong with the Prime Start. Hopefully, others will benefit from this exchange of information in the future...thanks again all...now, gotta go locate a Yamaha SERVIC MANUAL for future reference!!!...

 

[erniefish]

Re: Rodbolt and Yamaha Prime Start - Awesome

that is why this place and all its people are the best!!!!!!!!!,i do not even have prime start,but will be able to help any of my friends now,

 

[Loggerhead52]

Re: Rodbolt and Yamaha Prime Start - Awesome

That's absolutely correct Ernie. It's refreshing to know that there are still good hearted people in the world who are willing to lend a hand to total strangers who have never laid eyes on one another. I'm sure you read my post about the guy at the marina blowing me off and telling me I needed to just bring my rig in...I guess I could understand why he didn't want to being that it's why he's in business but what he failed to realize was that by helping me that one time, he could have gained my trust and quite possibly, I would have returned at some point in the future when I needed something done that I couldn't figure out...well, he kind of ruined the chance of that happening and now I feel like they would have charged me for carburetor rebuilds when they really didn't need it...oh well, it's water under the bridge and now anyone who performs a search on "Prime Start" will get a thorough lesson on how it works and how to repair it...well done to all who participated and thanks to Rodbolt and all technicians who freely share their knowledge with amateurs like myself...Thanks!

 

[Dog1234]

This thread looks old, but I just purchased a used 1999 90HP and need help. It is very hard to start on initial start up. After initial start up runs like a clock!!!!!. I have read several thread and it appears the prime start is always active until the engine warms up? (meaning letting extra fuel to #1 and #2 carbs)? I have taken the pump apart and all looks normal. The thermal valve moves as it should when I apply 12V to it. The diaphragm seem a little (crispy) in my opinion when move by my hand, but I am not sure whats normal texture of that.

So after cleaning checking reed valves and blowing air through fuel passages, I resembled the fuel pump. I checked crank case pulsation before it enters pump and appears to be good. I connected hose back, then I pumped the bulb tight applied the started with the hose going to #2 carb disconnected. (NO FUEL) coming out as starter turns. So if the fuel pump is working correctly shouldn't fuel be coming out that hose if the thermal valve is open until the engine warms up?

I am thinking maybe the diaphragm is not pulsating as needed. Any clarification would be great.

 

[GA_Boater]

This thread looks old, but I just purchased a used 1999 90HP and need help. It is very hard to start on initial start up. After initial start up runs like a clock!!!!!. I have read several thread and it appears the prime start is always active until the engine warms up? (meaning letting extra fuel to #1 and #2 carbs)? I have taken the pump apart and all looks normal. The thermal valve moves as it should when I apply 12V to it. The diaphragm seem a little (crispy) in my opinion when move by my hand, but I am not sure whats normal texture of that.

So after cleaning checking reed valves and blowing air through fuel passages, I resembled the fuel pump. I checked crank case pulsation before it enters pump and appears to be good. I connected hose back, then I pumped the bulb tight applied the started with the hose going to #2 carb disconnected. (NO FUEL) coming out as starter turns. So if the fuel pump is working correctly shouldn't fuel be coming out that hose if the thermal valve is open until the engine warms up?

I am thinking maybe the diaphragm is not pulsating as needed. Any clarification would be great.

Yeah - Over ten years old. Start a new thread.

Closed.