1989 200 Yamaha problems under load

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Re: 1989 200 Yamaha problems under load

BenC, where is the small engine fuel filter? Is that the one on the port side. With a semi clear yellow canister.<br /><br />Didn't get a chance to check it yesterday. I forgot I had an appointment with a heater guy to fix my central heat.<br /><br />Thanks in advance.<br /><br />Erik
 
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Re: 1989 200 Yamaha problems under load

Oh and it coughs ever so slightly at idle. You have to listen closely. But it does cough, no backfire though.<br /><br />Thanks in advance.<br /><br />Erik
 
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Re: 1989 200 Yamaha problems under load

Ok, the bottom fuel pump was leaking when I pulled the 2 bolts that hold the pump to the block and primed the bulb slowly.<br /><br />I pulled it off completely and took it apart. There was a 1/4" gash/hole in the rubber gasket.<br /><br />So i'm going to replace that tomorrow and hopefully take it out for a trial run.<br /><br />The question is now, would this explain the oily plugs, the loss of power under a load, but being able to rev the motor in neutral?<br /><br />I'm assuming, for that brief moment when I was able to do 23kts. that I promptly emptied the fuel bowls and with only one good working fuel pump, I was basically only able to run on 2-4 cylinders under load?!? What is your opinion on this?<br /><br />Thanks in advance.<br /><br />Erik
 

Canuck 16

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Re: 1989 200 Yamaha problems under load

I think you have likely found the cause of your problems!<br />It would probably be a good idea to replace both of those pumps.<br /><br />Good luck... Canuck 16.
 

rodbolt

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Re: 1989 200 Yamaha problems under load

if all you need is RPM throw the prop in the creek. we explained what happens when maint is not done and pumnps fail. were it me I would do both pumps at the same time. you can take 2 plugs out and toss them in the crick and in nutral it will still pass 4K
 

bigbrownbuku

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Re: 1989 200 Yamaha problems under load

Originally posted by stangclassic66:<br /> Oh and it coughs ever so slightly at idle. You have to listen closely. But it does cough, no backfire though.<br /><br />Thanks in advance.<br /><br />Erik
at this point i would take it too a professional eric.
 
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Re: 1989 200 Yamaha problems under load

BenC, so you think replacing the fuel pump wouldn't fix the problem?<br /><br />Thank in advance.<br /><br />Erik
 
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Re: 1989 200 Yamaha problems under load

Canuck and Rodbolt, I'm crossing my fingers. We'll have the replacement fuel pumps this afternoon. We'll install it and find out.<br /><br />Thanks in advance.<br /><br />Erik
 

rodbolt

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Re: 1989 200 Yamaha problems under load

the problem with a holed diaphram is twofold. one is the fuel bowls wont stay full. the other is the already lean mix is compounded by the extra raw gas flooding the cylinders and washing off the oil. so now we have a situation that the air/fuel mix is lean on some cylinders which can lead to piston failure coupled with lack of adequate lube due to excess gas on others leading to crank/rod/wristpin bearing failures.<br /> so your choice. pay now pay later. my shirt dont say maytag anywhere :) :) . that raw fuel has to go someplace.
 
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Re: 1989 200 Yamaha problems under load

New fuel pumps installed. Took the boat for a spin. Able to go a bit further but bogged again after 5 mins. This time I checked the primer bulb and it was dang near empty.<br /><br />Do I have a bad bulb?<br /><br />Thanks in advance.<br /><br />Erik
 

Canuck 16

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Re: 1989 200 Yamaha problems under load

Hmmmmm...<br />Well, you needed those fuel pumps anyways!<br />When you say the bulb was dang near empty, do you mean it was collapsed?<br />Does your boat have a built-in tank, or are you running on portable tanks? It's starting to sound to me like you have a gas tank vent problem. And yes, you could have a bad fuel bulb.<br />Did you have a look at that inline fuel filter?<br />I'm sure Rodbolt or Ray or Ben will be along soon to point you in the right direction.<br />Maybe to make it a little easier you could give us a little more detail on exactly what the motor did.<br /><br />Cheers... Canuck 16.
 
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Re: 1989 200 Yamaha problems under load

The bulb was not collapsed, it looked visually normal but when I squeezed it, it was not firm.<br /><br />So, I took it back home, took the cover off the motor and put the muffs on. Started her up and ran her at 2200rpm in gear, steady. I was watching the fuel filter case on the motor and it slowly drained, looked like fuel was dribbling in. I pumped the primer and it filled back up.<br /><br />There is a canister style fuel/water seperator right before the bulb. I'll replace the bulb and see how it runs tomorrow.<br /><br />Thanks in advance.<br /><br />Erik
 
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Re: 1989 200 Yamaha problems under load

It's low tide when I get home from work so I will not be launching tomorrow.<br /><br />Can I run engine with muffs and bring the revs up to 3000-4000rpm safely? I know it isn't really recommended to free rev in neutral so i'm trying to really keep that to a minimum.<br /><br />Thanks in advance.<br /><br />Erik
 

bigbrownbuku

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Re: 1989 200 Yamaha problems under load

muffs arent much good past 1500rpm. water pressure is to low to keep your pump cool = burnt impellor. <br />take your boat out again with a portable tank connected and see if the problem repeats. if it doesnt its a blocked supply. if it does its engine side and its time to second guess your fuel pump install.<br />a blocked supply could be anything from a kinked hose to a blocked filter. ive even had a hose partially collaps internally. all these problems are easy to find with a vacuum guage a plastic "t" and a piece of clear hose.
 
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Re: 1989 200 Yamaha problems under load

Alright folks, replaced the primer bulb with a Tempo brand primer bulb. Also replaced the soft fuel line between the seperator and bulb. And in between the motor and bulb.<br /><br />Took the boat out but couldn't test properly in 20knt winds and 2 ft. wind waves. Need FAC water to test right.<br /><br />One thing I noticed when starting cold with the cowl cover off, is there is a bit of fuel that spills from the carb cover (flame cover?) on initial startup. Once the motor has started and choke was let go, it's fine. When the motor is running at idle there is no fuel drip at all.<br /><br />Need the winds to lay down before I take it out again.<br /><br />Erik<br /><br />p.s. I've kept my appointment with the dealer in case I can't get this sucker fixed between now and the 22nd.
 

rodbolt

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Re: 1989 200 Yamaha problems under load

the soft bulb and the half full engine filter are all normal. they are on the suction side and its just how it works. however it should only take a squeeze or two to refill the system. all the primer is is just that. once the system is primed you can throw it away. the fuel out of the airbox is not normal. could mean the drain hose is off, your using to much choke or a needle valve is bad. tempo bulbs are the technicians friend, made a lot of money of them. good luck with it.
 
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Re: 1989 200 Yamaha problems under load

Thanks for the info Rodbolt.<br /><br />Is the drain hose something I could check? Is that in the airbox or in the carb?<br /><br />Thanks in advance.<br /><br />Erik
 

Canuck 16

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Re: 1989 200 Yamaha problems under load

stangclassic,<br />When you unbolted, and removed the second part of the airbox, two small hoses should have been disconected. One, around the center of it, and one at the botom. It's the lower line that Rodbolts asking you about.<br />Also, I should have posted back telling you to steer clear of the Tempo fuel bulbs. Aparently, it's hit or miss, wether you get a good one or not. Should have got the Yamaha bulb.<br />Let us know how it works out! You may need to go into them carbs yet!
 

omar3251

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Re: 1989 200 Yamaha problems under load

I know this is an old thread, but how this fuel issue ended, please don't forget to finished those threads, that way they could be more meaningfully.
Thanks
 
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