1995 Yamaha 200 =HP stalls stalls at idle

[Reel magic]

Hello guys I have a pair of 1995 Yamaha 200=HP engines.They have been runing excellent until the other day.We put the boat in the water cranked up the starboard engine ran great.cranked up the port engine and it cranked up but i noticed that it was idling very low rpm like 450 500 alomst stalling off.So I gave it a little throttle and it seemed to be sluggish.Kinda like it was missing on a cylinder or two.So I comtinued to let it idle again at 450 until it had warmed up.I took off the cowling to see if maybe a plug wire had came of etc.But everything looked intact.I then pulled off each plug wire 1 at a time and I noticed that when I would unplug #1 #2#5#6 plug wires that it made little different in how it was running.But when I unpluged # 3 and #4 cylinders the engine would stall out.I installed 6 new plugs and cranked it back up still doing the same thing?I did notice that all the plugs were wet with fuel so I know that the carbs are putting enough fuel into each cylinder enough to fire.I got out my Yamaha Service manuel and checked the Pulser coil it check within specs.I also checked the stator coil and it checked within specs and each coil checked within specs as well.Has anyone had this type of trouble or heard someone that has?If so what have you heard maybe what cures it?I also did a compression test before installing the new plugs and all cylinders were at 120 lbs.Help me guys.Any ideas????<br />Thanks in Advance

 

[Ray Neudecker]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

Need to check the fuel pumps next. You have done the basic electronic checks. Unbolt part way and squeeze the bulb (not too hard) and see if they leak. Replace (not repair) if leaking. The leak will be in the rear if bad.

 

[snapperbait]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

Maybe something like a fouled up sensor causing the engine to go into "limp home mode" ?? (forgot yammie system name)<br /><br />Otherwise, If your fuel system is up to par and the electrical system parts check out, I'd be looking towards the CDI..

 

[rodbolt]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

look at the fuel pumps. the cdi, if fed good voltage from the stator only stores it. if you have a min of 105volts(with a peak reading meter) on the coil primarys its probably not an ign problem. a bad pump will cause your problem as well as a bad needle valve. this is a fairly straight foward motor. works well rarely breaks.<br /> good luck and keep posting

 

[Canuck 16]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

Ray,<br />Is it ok to pull the pumps away from the block and test as you have described, and if the pump tests ok (no leaks), just tighten it back up without replacing the gasket?<br /><br />Thanks... Canuck 16.

 

[rodbolt]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

hello<br /> usually the gasket does not tear. what you are looking for is fuel leakage from the pulse hole in the aluminium back of the pump body. make sure the three body screws are tight. sometimes the pumps will leak if not bolted up. sometimes I have to but nuts on the bolt threads to keep the assy from leaking.<br /> good luck and keep posting

 

[Reel magic]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

Thanks guys for all the ideas.But if the fuel pumps or pump was bad . The spark plugs would not bet wet with fuel.Would they?<br />The cylinders that are not firing hard the plugs are all wet with fuel??<br />** Rodbolt ,,,,,What color wire should I check from the stator to make sure that I do have the (105)volts going to the CDI?I did check the Pulser coil it is reading 329 out of 256-384.Would the charge side of the Stator still charge 12.8-13.5? .Do I need to have the Batteries on for this test?Ignition switch on also?Thanks Guys

 

[Reel magic]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

To everyone that replyed to my posy.I did rebuild the carburators and fuel pump kits back in May 2004.Both engines ran super until now.The boat has been sitting for 2 months without runing.I used Yamaha Carb kits and after market fuel pump kits.I will check the fuel pumps pulse hole for fuel tomorrow.If this is true why would it only affect the 2 top cylinders and 2-bottom cylinders?I have noticed that when I pull off the plug wires off the top and bottom cylinders that the spark does not sound very loud.But when I do the middle cylinders the spark that comes from the coil wire sounds loaded?Can the Pulser coild be bad and check out OK?Thanks Again

 

[rodbolt]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

the pulser coils do not have any control over spark intensity. that is controled by the high and low speed charge coils. if a pump is leaking raw fuel into the crankcase it will make the plugs very wet. do you have a peak reading voltmeter? the cdi does not step up voltage. it passes whatever the charge coils give it when the pulser coil tells the scr to fire<br /><br /> good luck and keep posting

 

[Reel magic]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

Hello Rodbolt.I did check the fuel pumps they arte noy leaking any fuel when I unbolted them from the block and primed up my bubble.It holds very good tight bubble with no fuel from the fuel pumps .So the fuels pumps are ok.Next I will buy a Peak reading volt meter.How should I check the Peak reading from the charge coil?<br />Thanks Again

 

[rodbolt]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

hello<br /> the following do not apply if you have a P200, otherwise here are the specs.pulser coil for cyl's 1and 4 w/r(+)to w/g.<br /> cyl 2and5 w/b(+) to w/L.<br /> cyl's 3 and 6 w/y(+) to w/br.peak voltage loaded is 2.0 peak unloaded 2.5peak at 1500 rpm 9.5.<br /> low speed charge coil br(+) to r loaded145v unloaded140 v peak at 1500 rpm 170v.<br /> high speed charge coil L(+)to b/r 40 v loaded 40 unloaded and 170 v at 1500 rpm.cdi output b/w(+) to b 105 loaded and 170v at 1500 rpm.crank position sensor br(+) torunloaded cranking 3v. at 1500 rpm loaded 5.5vlighting coil unloaded cranking g-g 5.5v and 13v loaded at 1500 rpm.also check the spark plug caps 5Kohms. about now a service manual will be your best friend.<br /> good luck and keep posting

 

[Reel magic]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

I have a Yamaha Service manuel but your your spec above seem different than the Yamaha service specs?I will check this out tomorrow night.Thanks Again

 

[Reel magic]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

Rodbolt Anyway I can phone you??If so please post or (pm)me your ###.My service manuel gives me different specs than what you give me ? Like the pulser coil my Yamaha book states that the w/r-w/g should read 256-384 Q w/L-w/b read 256-388 Q and the w/Br-w/y should read 256-388Q .What I am doing or reading the manule wrong???<br />Thanks Again

 

[Ray Neudecker]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

The numbers you are quoting are if you ohm the coils. That is the impedance. Rob bolt is giving you the actual voltage while running. A more accurate test. Personally, I would be looking for a carb or fuel delivery problem such as a sticking needle. If you did not replace the bowl gaskets when the carbs were done, they will come apart and cause this problem.

 

[rodbolt]

Re: 1995 Yamaha 200 =HP stalls stalls at idle

hello<br /> i am with Ray.<br /> we just dont see many problems with that ign system, however on the rare occasion a stator will get weak and cause a low fireing voltage and cause wet fouling.<br /> email me at rodbolt40@yahoo.com