Chattering at 3K and hot sputtery death

[SSTKO81]

Hello from vacation. Took her out on the first run of the season and she ran beautifully up to 3500 RPM where I noticed a a chattering noise that ran in tune with the exhaust hum of the engine. I slowed down and the chatter quieted down. Seems sporadic.
Ran RPMs back uP to 3000 and noticed burning rubber/oil smell. -was running hot (190). Then she suddenly died and wouldn't start without a lot of cranking and throttling.
Before you say impeller, it's new. So is the thermostat. I was almost leaning toward detonation... But I don't know. Just a weird set of Problems.

 

[searay3]

Re: Chattering at 3K and hot sputtery death

You could have lost a coupler. Did you lose forward thrust? Look at the back of the motor and see if there is powdered rubber. That would cause your overheat. Could have locked up the outdrive assembly. If that checks out ok, look at the big rubber hoses at the top of the engine on the exhaust. If they have melted you have lost water circulation to the exhaust and will have to troubleshoot from there...

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

I did actually lose forward thrust just before it sputtered and died. I didn't notice a rubbery powder though... As far as the exhaust water circulation are you referring to the down pipe running from the manifold thru the transom? -no leak there.

 

[searay3]

Re: Chattering at 3K and hot sputtery death

Once the coupler goes, the outdrive stops spinning and there is no water circulation. I would suggest you get it out of the water, on a trailer, pull the drive and see whats what...there would not necessarily be a leak if the water stopped circulating to the exhaust...there are a couple of things that could cause the outdrive to stop spinning and overheat the engine.

 

[Bondo]

Re: Chattering at 3K and hot sputtery death

Hello from vacation. Took her out on the first run of the season and she ran beautifully up to 3500 RPM where I noticed a a chattering noise that ran in tune with the exhaust hum of the engine. I slowed down and the chatter quieted down. Seems sporadic.
Ran RPMs back uP to 3000 and noticed burning rubber/oil smell. -was running hot (190). Then she suddenly died and wouldn't start without a lot of cranking and throttling.
Before you say impeller, it's new. So is the thermostat. I was almost leaning toward detonation... But I don't know. Just a weird set of Problems.

Ayuh,... That's probably what the noise was,...
Donno why ya lost thrust,...
Check the drive oil, if ya don't find ground metal,..
Pull the drive, 'n look at the coupler...

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

I was going through a few basics earlier; changed the plugs out and made sure the oil was clean (it is). In doing so I noticed there was a little play in the rockers. I tightened almost everyone of them down by 1/8-1/2 turn. -cOuld helP explain the chattering. What do I do to check the possible detonation issue? The old plugs were pretty burnt looking. -no white on the ceramic.
As far as the coupler, it'll be a couPle days before i can check it. Is that pretty much what ties the drive to the engine? -the drive/lower unit is my personal weak point...

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

So if the coupler is trashed am I going to have to pull the engine? Or is it some thing that I can get to when I remove the drive? Is there a diagram for this somewhere?

 

[alilley]

Re: Chattering at 3K and hot sputtery death

if it is the coupler, yes you will have ot pull the engine but dont sweat it as it is a hole lot easier to pull the engine in a boat then a car or truck.

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

A little follow-up. Went down and started her up this morning. Decided the tuning wasn't quite right so after a lot of tweaking i finally got it where I'm happy. But while doing this I noticed it never even got close to over heating after and hour of idling. -no load, I realize. But I put it in gear, made a few short runs around the cove and she was fine... Still sound like a coupler? Only problem I noticed this time was lower oil pressure.

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

Went out for a run across the lake yesterday, she got a little warm (180) but never got in the red. Is the coupler one of those Parts that just goes? Or will it slowly disintegrate with a few tell tale signs? -like what? -cause I lost power about half way back; in WOT she only got to 2500 RPM (?)
Thanks guys

 

[Bondo]

Re: Chattering at 3K and hot sputtery death

Is the coupler one of those Parts that just goes?

Ayuh,.... All or Nothin',...

What do I do to check the possible detonation issue? The old plugs were pretty burnt looking. -no white on the ceramic.

That sounds like Detonation...

Gota picture,..??

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

I don't have pics right now but I can tell you two of em were black on the ceramic and had some carbon chunks on the electrodes (and these were the platinum type). The other two were fairly normal looking, grey ceramic, but still a little carbon.

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

I checked the timing just a week ago on the muffs once engine was warmed up. It's set to factory 6BTDC. And I'm running new 91 octane fuel on new filters. I'm wondering if I need more advance or retardation? It's vibrating relentlessly right around idle and just doesn't wanna stay running unless I continually throttle up.

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

Alright, went out for a run today and she started right up and idled nicely out of the cove but once I got out and tried to open her up it sounded like a lawnmower and had no power. So I backed her down to 1500 and limped her home. I swear it sounds line the sputtering is coming from the carb itself. Thoughts?

 

[SSTKO81]

Re: Chattering at 2K and hot sputtery death

Re: Chattering at 2K and hot sputtery death

[/B][/B][/B][/B]
Quick look at the plugs I pulled. Still not sure how to fix the detonation issue. I went back and tried retarding the timing a couple of degrees and that only seemed to hurt the situation.
I've been thinking of worst case scenarios and I'm wondering if it could be a cracked head or manifold. I'm going to pick up a pressure guage today to I can try to track down the problem. I took off the intake/exhaust manifold and found what looks like burned/rusted spot on the manifold, gasket, and heads. Not to mention rusty spots on the valves inside. Normal?

https://picasaweb.google.com/111125...&authkey=Gv1sRgCPfY8Mrwor76DA&feat=directlink

Also included this video link for some sight and sound on my issue.

 

[SSTKO81]

Re: Chattering at 2K and hot sputtery death

Re: Chattering at 2K and hot sputtery death

back to top:::

 

[Bondo]

Re: Chattering at 3K and hot sputtery death

Alright, went out for a run today and she started right up and idled nicely out of the cove but once I got out and tried to open her up it sounded like a lawnmower and had no power. So I backed her down to 1500 and limped her home. I swear it sounds line the sputtering is coming from the carb itself. Thoughts?
Still not sure how to fix the detonation issue.

Ayuh,..... My guess is it's Starvin' for Fuel...

The #1 leading cause of Detonation....

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

I agree completely. However, if I run a water hose through my manifold I don't think I should see watter flowing through the exhaust ports should I? there appears to be a large crack between the manifolds water jacket and the exhast runners. Couldn't this act as a serious obstruction to flow causing back pressure and Detonation-like symptoms?

 

[Bondo]

Re: Chattering at 3K and hot sputtery death

I agree completely. However, if I run a water hose through my manifold I don't think I should see watter flowing through the exhaust ports should I? there appears to be a large crack between the manifolds water jacket and the exhast runners. Couldn't this act as a serious obstruction to flow causing back pressure and Detonation-like symptoms?View attachment 102480

Donno,... Put on a set of new manifolds, 'n Try it...

 

[SSTKO81]

Re: Chattering at 3K and hot sputtery death

LOL... right on top of that. I'll post on how it goes.