Problem with the engine

[Scarabsteve]

So I'm out on the lake jetting around when all of a sudden my engine kind of sputters. At first I thought I hit something but I looked around and I was clear. I try to go again and I'm in drive but the engine just keeps revving like it's in neutral. Now I could go a little bit but not over 3k Rpms. Took me forever to get to my lift but any way got the boat up there and checked under the drive. Nothing in their nothing looked like it was clogged. So did I screw up my engine or what? I was going to take it to marinemax but thought I'd try here for help and try to save some money. Any advice?

 

[Trm1765]

Plugs Loose, Not Locked? That Would Be My First Guess.

 

[Scarabsteve]

what does that mean

 

[PaulyB]

He is referring to the Clean-out plugs on a Yamaha, he probably didn't notice you were in a Scarab. My first thought was clean-out plugs as well, but your boat shouldnt have any....

 

[Scarabsteve]

He is referring to the Clean-out plugs on a Yamaha, he probably didn't notice you were in a Scarab. My first thought was clean-out plugs as well, but your boat shouldnt have any....

What else could it be?

 

[Murf'n'surf]

You may have injested debris and damaged your impeller and/or impeller lining/wear ring. Sorry I'm not familiar with Scarab pumps -- not sure if you have a liner or housing. My guess is your liner is damaged or even missing.

You need to look at the clearance between your impeller and housing or ring. Should be no more than a few business cards thick. See any gouges? Pics would help us.

 

[Scarabsteve]

You may have injested debris and damaged your impeller and/or impeller lining/wear ring. Sorry I'm not familiar with Scarab pumps -- not sure if you have a liner or housing. My guess is your liner is damaged or even missing.

You need to look at the clearance between your impeller and housing or ring. Should be no more than a few business cards thick. See any gouges? Pics would help us.

Good idea. I'll take one tomm

 

[PaulyB]

How many hours are on the boat? Was the engine broken in properly? It sounds like it could possibly be a catastrophic engine failure. Pull the spark plugs and look for any shiny metal on the tip... I once has a problem similar on an outboard motor and ended up blowing a hole in a piston....

 

[Scarabsteve]

How many hours are on the boat? Was the engine broken in properly? It sounds like it could possibly be a catastrophic engine failure. Pull the spark plugs and look for any shiny metal on the tip... I once has a problem similar on an outboard motor and ended up blowing a hole in a piston....

I have 15 hrs on her. Yes I broke it in properly

 

[PaulyB]

How fast were you running when it bogged down? How far did it bog down?

 

[Scarabsteve]

How fast were you running when it bogged down? How far did it bog down?

I was only going about 20 mph I was in 10 ft of water then the engine started making that revving noise so I thought I hit something

 

[Bruce]

If something gets clogged in the jet cavitation will occur. While cavitating the jet will spin at high rpm without moving much water. You would likely feel vibration. With a twin engine boat vibration is the biggest indicator.

If you had clean out plugs you would stop the engine, pull the plug and reach in from above to clean out whatever is in there.

Hopefully if you put it on the trailer you will see something in the jet and be able to remove it.

 

[Williamsone46]

If you engine revs but won't go I would suspect it has more to do with the drive system and not the motor. Start checking drive shaft, impeller, wear ring, etc. It could be your reverse bucket is stuck somewhere in the neutral position, but that would be a long shot.

 

[ScarabMike]

That sounds a lot like your computer in "docking mode".

Turn on the boat to engine on, but don't actually turn it on. Hold the Set and Mode buttons for 6 seconds. Turn it back off, then start the engine. You computer should be reset. If it happens again, then get Marine Max to reload/rewrite the ECU. You should be ok after that. It only takes about 30 seconds. While your there, have them check the MAF sensor for debris.

You jet system is ok. You have a sleeve protecting your shaft.

 

[aarons1k]

Check engine light on ?

 

[Scarabsteve]

Check engine light on ?

No its not

 

[Scarabsteve]

That sounds a lot like your computer in "docking mode".

Turn on the boat to engine on, but don't actually turn it on. Hold the Set and Mode buttons for 6 seconds. Turn it back off, then start the engine. You computer should be reset. If it happens again, then get Marine Max to reload/rewrite the ECU. You should be ok after that. It only takes about 30 seconds. While your there, have them check the MAF sensor for debris.

You jet system is ok. You have a sleeve protecting your shaft.

Mike your the man. I did what you said it fixed it. What causes the computer to do that or does it just happen? Thanks everyone for the help saved me a trip to the dealer!

 

[ScarabMike]

@Scarabsteve it happens sometimes when you first start the engine, and the computer is in the middle of resetting, and getting ready for starting. Make sure when you start the boat to wait till the dash finishes its "sweep". It will then clear itself, and revert to normal.

 

[Scarabsteve]

@Scarabsteve it happens sometimes when you first start the engine, and the computer is in the middle of resetting, and getting ready for starting. Make sure when you start the boat to wait till the dash finishes its "sweep". It will then clear itself, and revert to normal.

Thanks for the tip

 

[ScarabMike]

@Scarabsteve No problem! Now you owe us pics of the ride!!