3.0 Sea Ray dies at idle

[Becka]

2008 Sea Ray 175 will not run at idle speed.
I have drained all gas, replaced with fresh. Tried adjusting the idle setting. Pulled and soaked carb jets. Replaced gaskets and re-installed. Still having the same problem.

When I crank it cold, it runs until up to temp(auto choke?) then dies. I can keep it running with throttle, but just not at idle.

Any Suggestions??
Thanks!!

 

[tdappleman]

The TKS has an electric choke which may be sticking. Have you looked to see it is fully opened when it has warmed up? I'd also check all of the linkages to make sure they are all moving freely and lubricate them if you haven't already done so. I have to remove my throttle linkage on my engines to move all of the linkages. Does running it without the flame arrestor make any difference at all? May be time to clean it before you reinstall.

 

[BonBini]

From your description, this sounds to me like your engine is starving for gas possible due to the idle circuit being plugged.

When did this problem surface?

Does your carb have a set of idle mixture screws?

Can you keep it running when you choke the top of carb with your hand?

 

[Becka]

From your description, this sounds to me like your engine is starving for gas possible due to the idle circuit being plugged.

When did this problem surface?

Does your carb have a set of idle mixture screws?

Can you keep it running when you choke the top of carb with your hand?

Problem started after the boat sat up for 2-3 months. I didnt use any gas treatment as I usually run the boat often. Boat ran fine for about 5-10 minuites, then died, and I was able to putter back to the ramp. Drained fuel, replaced with fresh. Now the boat runs fine in nuetral with throttle(above 1.5K RPMs) Ran new gas threw at different RPMs for over an hour. Still dies at idle. Now, when I start it cold it idles fine(high, due to auto choke). I removed the carb, disassembled and did a soak, replaced, and the same issues exist. Will run choked, or with throttle.

There is not a mixture screw on this carb. The only adjustment is an idle setting on the throttle linkage, Ive tried every setting possible.

I guess I need a complete carb rebuild? Less than 2 yrs old, I figured that wouldnt be nessasary. The inline filter at the carb inlet was clean, not a spec.

Thanks for the help, Im just at ends with this one....

 

[sr330daguy]

From your description, this sounds to me like your engine is starving for gas possible due to the idle circuit being plugged.

When did this problem surface?

Does your carb have a set of idle mixture screws?

Can you keep it running when you choke the top of carb with your hand?

What he said...

 

[Fun Times]

When the engine is warm try unhooking the hose going to the pvc valve or the fitting on the valve cover, That is if your application has one going to the valve cover, Because so far I have seen in the past that on the V6 and V8 engines, If the engine stays running after unhooking the hose, you are going to need a new carburetor, I do not think a rebuild is going to fix it. I had no luck with rebuilding the carburetor.
When the (TKS) engine is running right, The engine will normally die when you unhook that hose going to the valve cover, But if it stays running then I have had to replace the carburetor each time. But I have never messed with the 3.0 TKS to know if it's the same way as the V6 and V8.

Did you buy the extended Product Protection plan?

 

[BonBini]

If you've got no mixture screws on the lower throttle plate body portion of your carb... Are they hidden behind a factory cap or plug?... Or do you perhaps have an electric sol device down in that area?

I'm not familiar with TKS. I'm assuming there must be some sort of idle circuit!

 

[stuckinforward]

MFT, choke, or vacuum leak, but without being on the boat its hard to troubleshoot,
always keep in mind when troubleshooting, the boat needs 3 things, air,fuel, spark. a choke would fall under air, vacuum would fall under air. if those check out move onto the fuel side, i find it easier to troubleshoot this way or you will be using the ole parts swap process of elimination. a vacuum test at idle will tell you many things, dont concentrate on one thing.....anything is possible

 

[wakeup 19]

I am sure you changed the water separator, but I didn't see it mentioned. If not you may want too.

 

[Lazy Daze]

I'm not able to give much info on the TKS... other than the basics of how it works - but that is pretty basic. What I can tell you is that it seems as though it's one of those things that either works great or has problems. Your symptoms sound an awful lot like complaints we've gotten where the problem ended up being the TKS. Not sure that's worth a full 2 cents, but you can have it regardless! :smt001

 

[Becka]

I'm not able to give much info on the TKS... other than the basics of how it works - but that is pretty basic. What I can tell you is that it seems as though it's one of those things that either works great or has problems. Your symptoms sound an awful lot like complaints we've gotten where the problem ended up being the TKS. Not sure that's worth a full 2 cents, but you can have it regardless! :smt001

TKS? Im a Sea Ray ameture here, My previouse was a 1986 Correct Craft. But anyway, TKS=Turn Key Start. I thought that just meant its carborated. Are there electronics involved that could be malfunctioning?

The first thing I tried to do is check the separator. I found out quick that this model doesnt come with one. I will be installing an aftermarket. This is the main reason Im leaning toward carb issued, but if it was just moister, a good soak should have cleared things up.

Thanks for the feedback fellows!!

 

[Lazy Daze]

It's an "auto" choke feature that uses a wax-like substance to control the choke. When the wax is cold, it holds the choke - as it warms up, it slowly starts to release. Sometimes it doesn't behave and it doesn't release. It may or may not be your problem - but it does sound awful familiar. You can probably find out more about TKS either on Merc's site or just Googling.

I'm sure Travis was thinking the same thing.

 

[Becka]

It's an "auto" choke feature that uses a wax-like substance to control the choke. When the wax is cold, it holds the choke - as it warms up, it slowly starts to release. Sometimes it doesn't behave and it doesn't release. It may or may not be your problem - but it does sound awful familiar. You can probably find out more about TKS either on Merc's site or just Googling.

I'm sure Travis was thinking the same thing.

OK thanks for clearing that up. Im thinking that feature is operating correctly, just when engine warms up, the choke closes, then the engine dies. As far as I can tell, you are extremely limited as far as adjustments to this particular carb. It seems to be very basic, but thats what has me baffled!!

 

[BonBini]

Is this your carb?

Item 25 is idle mixture screws that look to be factory sealed. They are adjustable.
Item 1 is an enrichment module. Most likely only influences the main circuit like a power valve.

Try holding your hand over the carb to choke it. If your idle speed returns to normal, most likely the idle circuit. If your idle returns and is abnormally high, most likely a big vac leak.

Let us know... And this thing is firing on all four cyls right? Its not doing something like droping one hole at low idle and then coming back in with rpms!

 

[govols019]

OK thanks for clearing that up. Im thinking that feature is operating correctly, just when engine warms up, the choke closes, then the engine dies. As far as I can tell, you are extremely limited as far as adjustments to this particular carb. It seems to be very basic, but thats what has me baffled!!

Just so you don't feel alone, mine does the same thing. Once it's warm it doesn't like to stay running at idle. Have to keep the throttle at a fast idle while at the dock. Done it since day one.

 

[Fun Times]

Just so you don't feel alone, mine does the same thing. Once it's warm it doesn't like to stay running at idle. Have to keep the throttle at a fast idle while at the dock. Done it since day one.

You should get that boat in for a check up also,:wow: You still have Warranty?

Within two years I have had to replace five TKS style carburetors that ran like this under Warranty.

(FYI) MerCruiser does not like to do rebuilds if it's still under Warranty in some cases.:smt038

 

[Lazy Daze]

Just so you don't feel alone, mine does the same thing. Once it's warm it doesn't like to stay running at idle. Have to keep the throttle at a fast idle while at the dock. Done it since day one.

I'll give a big "ditto" to what Boat Tech said. I sure hope that no one told you anything like "Don't worry, that's just the way those 3 liters are". Overall, it's a very good little engine - but something isn't right. It should idle just like any other engine.

 

[Becka]

Is this your carb?

Item 25 is idle mixture screws that look to be factory sealed. They are adjustable.
Item 1 is an enrichment module. Most likely only influences the main circuit like a power valve.

Try holding your hand over the carb to choke it. If your idle speed returns to normal, most likely the idle circuit. If your idle returns and is abnormally high, most likely a big vac leak.

Let us know... And this thing is firing on all four cyls right? Its not doing something like droping one hole at low idle and then coming back in with rpms!

That is very close to my carb. I did not access item 25 when I had my carb out. All I really did was remove it, soak the jets, and replaced it. Now Im thinking about either a complete carb rebuild kit, or just replace the carb, like boat tech said. Its not under warranty any more. Any suggestions on where to get any of these items?

 

[govols019]

You should get that boat in for a check up also,:wow: You still have Warranty?

Within two years I have had to replace five TKS style carburetors that ran like this under Warranty.

(FYI) MerCruiser does not like to do rebuilds if it's still under Warranty in some cases.:smt038

Yeah, still have one year left on my warranty. Guess that gives me something to do tomorrow.

It idles great at 1,000 RPM out of gear. The normal idle RPM out of gear is around 800. At that point it will idle rough until it dies.

At no wake speed it runs but will just be a little rough.

Lazy Daze is right. I've been told that 3.0 was just a rough idling motor. That was from previous owners of 3.0's and not from my repair shop. I'll run the boat by there tomorrow. Hope they can get to it soon.

 

[BonBini]

Becka: If you've decided its a carb issue and your without warranty, you should be able to work those factory seal caps off. Usually destroying them, you wont be putting them back on! Pull the carb back off to do it. They look very similar to ones used on GM carbs some years ago. Some times the screws have a different type head.

Fully seat the metering screws (gently!) counting the turns on the way in for reference. Now remove the screws completely and blast the hole with carb cleaner from the straw(watch your eyes). You should get flow from a hole near throttle plate and an air bleed in the ventury area. Blast these exits too if you can. Take turns blocking these exits with your finger to get passage ways cleared good.

The Merc guys are most likely right on replacing the carb, but to me it sounds too much like component based troubleshooting. You really haven't confirmed it is the carb, so if you replace it and the problem remains, your out allot a bucks... A test carb would be nice!