1994 200 HP Johnson Stalls above 1000RPM

[RHB]

Thanks in advance for any advise, as always much appreciated.<br /><br />Motors ran OK offshore all day until..<br /><br />Port engine stalled on ride in. The motor would start and idle OK. It would fast idle Ok. It stalled when I engaged forward and exceeded 1000 RPM. No overheating was evident.

 

[clanton]

Re: 1994 200 HP Johnson Stalls above 1000RPM

Check upper crankshaft bearing housing bolts, magnets in flywheel.

 

[RHB]

Re: 1994 200 HP Johnson Stalls above 1000RPM

I don't understand why you suggest magnets, and or bearing housing bolts? Can you give some explanation? I am not all that familiar with this sort of motor failure.

 

[clanton]

Re: 1994 200 HP Johnson Stalls above 1000RPM

The bolts come loose for different reasons, and when they do your problem is a symptom,if the bolts are backing out, and you dont catch it in time, it may ruin the crankshaft and block. The magnets in the fly come loose and wedge into the stator, or move around and the ignition becomes intermittent. May not be your problem, but worth a check, loose magnets very common problem.

 

[RHB]

Re: 1994 200 HP Johnson Stalls above 1000RPM

Thanks for the info. I will check as you suggest.

 

[RHB]

Re: 1994 200 HP Johnson Stalls above 1000RPM

I went to dealer before I went to the boat. He believed the problem was fuel related. Sold me a new VRO pump.<br /><br />I installed the new pump and new primer bulb but the problem is the same.<br /><br />I pulled the plugs, they all look good, cleaned and gapped them.<br /><br />I had no way of pulling the flywheel this trip. I'll have to buy a puller before my next trip to the boat.<br /><br />Learning the hard way.<br /><br />RHB

 

[clanton]

Re: 1994 200 HP Johnson Stalls above 1000RPM

You should be able to see the bolts and magnets without removing the flywheel.<br /> Check compression.<br /> Check spark, should jump 7/16 gap at cranking rpm with plugs in.<br /> Fuel pressure 3 lbs at idle.

 

[RHB]

Re: 1994 200 HP Johnson Stalls above 1000RPM

Thanks for the help.<br /><br />I did look at the magnets and bolts. I did not see any thing unusual.<br /><br />I'll check compression as you sugest.<br /><br />Where should I measure the fuel pressure? I assume somewhere after the pump before the fuel manifold.<br /><br />I have been reading the service manual and I am stumped by a few items.<br /> <br />The SLOW circuit has me wondering. A tan wire from the power pack is tied directly to temperature switches mounted on the power heads. The tan wire is also connected through a blocking diode to the VRO pump, a fuel vacuum switch, an oil tank level switch and is wired through the harness to the front instrument assy. How can the power pack decide what type of failure is occuring when it appears the sensors are switching the tan wire to ground? Can I disconnect the tan wire to see if this might be a cause of my trouble? (false SLOW activation)<br /><br />The manual shows an anti-siphon valve test. I don't know where the valve is located.<br /><br />Any advise whould be helpfull.<br /><br />RHB

 

[clanton]

Re: 1994 200 HP Johnson Stalls above 1000RPM

The blocking diode blocks the other sensors, disconnect tan wire at pack and try it. Check fuel pressure between the pump and carbs. Be vEry careful when removing hose from pump,nipple will break. Remove hose to vacuum sensor at T from main fuel line connect vacuum gauge. Sears has combo fuel pressure/vacuum gauge for about 20.00. What does spark look like?

 

[RHB]

Re: 1994 200 HP Johnson Stalls above 1000RPM

I have not checked spark yet but will do next trip to the boat.<br /><br />I'll check fuel pressure and vacuum. Should I expect a constant pressure or will it vary with load/speed.