mercury motor- very sick- needs a doctor

[waterdog101]

first let me say thanks, to all that responded to the post no this motor being hard to start. now i need some advice on a new problem, same motor. this is the newest motor i've ever owned,it's a 90 hp two stroke 2006 mercury. and it has been hard to start but always run great, last week i was fishing, fired up and going down the lake about 40 mph and it just shuts off like it's out of gas. it fires right back up, planes off runs great for 2 minutes shuts off again, it does this all the way back to the boat ramp and never any power loss. i bring it home. i replace the fuel filter with a new one, i replace the pump up fuel bulb with a new one, replace the plugs with new ones. take it back to the lake, fire it up and it runs great with plenty of power, planes off runs up to 5300 rpm. i stop it and try it again, it runs great only i hear this new sound it never made before, it sounds like a old car engine that the valves are picking in. it runs great but after this has happen, it sounds really bad, any one ever had this problem, or know what my problem could be. please, let me know. i'll have to try to fix it myself. thanks for reading this and hope some one can help.

[dausefarms]

Need to have the compression checked. Mine done the same thing and ended up blowing the motor on my merc. 200efi. This new gas is killing motors left and right.

[waterdog101]

Need to have the compression checked. Mine done the same thing and ended up blowing the motor on my merc. 200efi. This new gas is killing motors left and right.

thanks, for the reply. I will check the compression, i don't know how much it should be. but they all should be the same. if one has less compression, does that mean a broken ring? and could it have a broken ring and still have plenty of power. and if all check the same, now what would you think the picking noise could be.

[steemer1]

Check the compression I blew a rod completely through the top of my 200 Johnson venom. Now I have a new 225 Etec Evinrude on the back of my 201 Stratos.

[Embrey]

Check the compression I blew a rod completely through the top of my 200 Johnson venom. Now I have a new 225 Etec Evinrude on the back of my 201 Stratos.

well a rod probly wont show any different on a compression test sadly. but if he was starving it for gas, it could have definately hurt a rod ,being a 2 stroke. if it makes that noise at idle, you could pull one plug wire at a time and see if it goes away on a certain cylinder. might lead to figuring out whats up

[waterdog101]

well a rod probly wont show any different on a compression test sadly. but if he was starving it for gas, it could have definately hurt a rod ,being a 2 stroke. if it makes that noise at idle, you could pull one plug wire at a time and see if it goes away on a certain cylinder. might lead to figuring out whats up

I've been busy today, but i did go get a compression gauge. it was dark out so i didn't warm the motor up before i checked the pressure. i'll have to do it over. but the cold check was 130 psi on all 3 cylinders. and i thank you for the reply. what you said about the noise at idle, and pulling a plug wire. made me think of something. when at full throttle the noise went away, or i just could not hear it. so if it is a rod barren making the noise while at an idle or low throttle. when at full throttle it would have enough pressure on it to take the noise away. does this make sense?

[Embrey]

could be...rods usually make the most noise at idle or after revving on the way back down. not always, but usually

[waterdog101]

could be...rods usually make the most noise at idle or after revving on the way back down. not always, but usually

thanks, for the reply. that could be it. I will try pulling the plug wires one at a time. to find the one it is. it just don't make sense, almost a new motor. and it's gone bad. and the last motor i had was a rebuilt 20 year old johnson, and i ran it 7 years trouble free.

[dausefarms]

Is the motor fuel injected? If it is possible injector.

[Embrey]

true...but if its that, he would notice major performance loss i would think

[waterdog101]

true...but if its that, he would notice major performance loss i would think

I went to the lake today, this motor has plenty power. i laid down and put my head back close to the motor. while it was idling. the sound, sounded like it was in the area at the bottom of the motor, and at the top of the shaft. how can i tell if it has a problem with a rod or bearing. with out tearing the motor apart. and standing behind the motor, the prop can be pushed in about a inch. is this normal for the prop to have enough play to push in and pull out about an inch.

[Embrey]

probly not much of a way other than pulling the plug wires. did you try that? and the prop doesnt sound right. id take it off and see whats up there. does it make the sound in neutral, in gear or both? if it does it in neutral also, is say the prop and lower unit isnt the problem, cause it shouldnt be spinning in neutral