Need help!

[Robert_o]

@Robert_o. I would still consider bringing it to a good Yamaha dealer. There may be something Yamaha will do if this is a known issue.

That's exactly what I will do, I have exhausted my very little knowledge I have. I will keep everyone posted and thank you again for all of your suggestions .

 

[2nazt]

Can you please explain step by step how you tested compression? You said you were at WOT? My thought why. I think you did the test wrong.

 

[Robert_o]

Can you please explain step by step how you tested compression? You said you were at WOT? My thought why. I think you did the test wrong.

Hi, removed all the spark plugs, place throttle in neutral ,removed lanyard,screwed the gauge into the 1 cylinder then I turned key to start. I then went down the line to the other 3. The reason I said WOT is because at first I thought it would be like a car when testing compression , but then I remembered that our boats won't start if not on neutral . Sorry for the confusion .

 

[swatski]

@Robert_o All I can say is I'm watching and routing for you!

 

[Gym]

Hi, removed all the spark plugs, place throttle in neutral ,removed lanyard,screwed the gauge into the 1 cylinder then I turned key to start. I then went down the line to the other 3. The reason I said WOT is because at first I thought it would be like a car when testing compression , but then I remembered that our boats won't start if not on neutral . Sorry for the confusion .

What we're your readings @Robert_o?

 

[2nazt]

Wait removed lanyard?

 

[Robert_o]

What we're your readings @Robert_o?

I didn't get any!

 

[Bennie]

I didn't get any!

That's not right!

You should get some compression. Even if your chain was completely broken you would still get more than zero. Maybe low teens, but still you will get more than nothing.

 

[Hana]

I didn't think the motors would turn over with the lanyard removed.

 

[2nazt]

They should crank but no spark, with all plug removed though you didn't really have to pull lanyard. Did motor crank?

 

[Robert_o]

They should crank but no spark, with all plug removed though you didn't really have to pull lanyard. Did motor crank?

Yes it does crank

 

[njmr2fan]

If the Pistons are moving up and down and forcing puffs of air out are you still looking at a broken timing chain?

 

[Gym]

@Bennie is correct. The Pistons are connected to the crank shaft. The timing chain only operates the valves. Turning the key engages the starter motor which turns the crank shaft causing the Pistons to pump air. You should get some readings and one cylinder will be on the compression stroke with closed valves giving you a normal reading. The rest of your cylinders will give low or no reading.

Is there a compression release knob or button on your compression gauge that may be in the open position? Some gauges have this feature so you can disconnect the gauge and keep the reading on the gauge until you record it. Then you turn the knob or press a button on the gauge to zero the gauge for another reading.

 

[veedubtek]

It's highly possible to have 0 in all cylinders. Actually very likely if it broke at speed. It bent the valves. And pulling the lanyard was correct, as that will disable the injectors as well. Excess fuel in there not burning can alter compression readings by washing the oil off the cylinder walls.

 

[Robert_o]

OK guys update... dropped boat off today a dealer and within 3 hours I was called back and was told that the boat has ZERO compression, yes its crancking but the cams not turning. The engine will have to be pulled apart and search deeper into what the problem is. Yes I think we all know now that its a broken chain but I am hoping its nothing more. Like I stated in my OP , the boatonly has 98 hours,babied , how did this happen? anyone have any experience with Yamaha on issues like this?
thanks

 

[2nazt]

I've heard isolated cases. Maybe a bad run of parts from supplier? Either way I hope no other problems and you get on the water again soon.

 

[itsdgm]

Sorry to hear that @Robert_o not sure where you're at with a warranty, but I'd put a bit of pressure on Yamaha to help you if you're out of warranty. Best of wishes, keep us up to date.

 

[McMark]

Timing chain mojo on the way.

 

[Gym]

@itsdgm is correct. Yamaha is aware of these issues and if pressures should help out.

 

[njmr2fan]

Well I had hoped for better news for you, but that was my fear early on. Sorry to hear. I wonder does anyone here have an ear of someone at the company that could help?