1997 Larson 186 Losing power and stalling

I just purchased a 1997 Larson 186 LXI with a Volvo Penta 3.0 liter I/O. The boat randomly loses power (hesitates, RPM drop) at various speeds and stalls out quite a bit at idle. It always restarts immediately. This happens on both a cold and warm engine. It does not appear to be related to speed or temperature. I'm sure its a fuel issue of some kind. The previous owner had the fuel pump replaced last season (so he says). Could be a carburator issue which I am confident I could pull and rebuild. But before I do all that, are there any other quick troubleshoots I should do first. This is my first boat, but I do have some experience working on engines (cars and bikes), so not a total novice here.

Tried to search, but I am not finding much and I can't get the advanced search to load.

Thanks in advance for any advice/tips you guys have.

-Joe

Re: 1997 Larson 186 Losing power and stalling

Howdy,


The only time I had a problem like that was when I had debris in the tank. it would clog (intermittently) the fuel pickup screen.



Your best bet for a suspected fuel blockage problem is to start at the tank fuel pick-up and work towards the carb.

If it's an old boat, or a boat with a fiberglass tank, there could be other problems with E10 fuel exacerbating the problem (fiberglass interaction with E10). Cleaning everything helps. If you have a fiberglass tank, you may have to replace it (if that's possible)


Cheers,


Rick

Re: 1997 Larson 186 Losing power and stalling

Ayuh,... Start by checking,+ changing the Fuel Filters...

Re: 1997 Larson 186 Losing power and stalling

Here is how you test it to find where the problem is.

http://forums.iboats.com/showthread.php?t=283269

Re: 1997 Larson 186 Losing power and stalling

Thanks for the help so far. At this point I do not think it is fuel system related. Heres the UPDATE!!

So I believe I was wrong the first time. The problem only seems to happen when the engine reaches operating temperature. So now I am leaning toward something ingnition related? Any thoughts.

The engine is again is a volvo penta 3.0 GS PLKD

Thought I read something about a similar problem, but I have been searching and I can't find the thread to save my life.

-Joe

Re: 1997 Larson 186 Losing power and stalling

The problem only seems to happen when the engine reaches operating temperature.

Click to expand...

Ayuh,... That's when the Choke fully Opens,...
It still sounds like Crap in the Carb..

Re: 1997 Larson 186 Losing power and stalling

DeaconBlues said:

Thanks for the help so far. At this point I do not think it is fuel system related. Heres the UPDATE!!

Click to expand...

I had the same thing, in a different boat. It was a clogged fuel pickup. Exact same symptoms.

So now I am leaning toward something ingnition related? Any thoughts.

Click to expand...

Build the tool in DonS's link. Then you will *know* if it's fuel delivery related or not. Taking the guesswork out leads to much happiness out on the water.

Thought I read something about a similar problem, but I have been searching and I can't find the thread to save my life.

Click to expand...

Here is my thread with symptoms and the fix. You can read it all, or scroll down to "Third issue" and skip the rest. Bonus: it contains the same link DonS posted.

Re: 1997 Larson 186 Losing power and stalling

Ok, went throught the fuel system checks per the instructions. Everything is good to go. Drained the fuel as well in case it was old.

Problem is still occuring and still only at operating temperature (around 150)

Rebuilt the carb, and was pleasently surprised at how clean it was.

Problem is still occuring and still only at operating temperature

On to electrical/ignition. Distributer looks good. All connections all over the boat are secure. The boot on the wire to the coil is burnt orange. Didn't notice it at first because I thought that was just the color it was originally, but it is gray on the inside. I changed this wire and the problem is noticably better. now it only dies every few minutes or less as apposed to every 30 seconds. And these stalls might be related to some old gas still in there. This was all performed on muffs, so we will know more when I get it in the water. Good be the coil getting hot and that would explain the burned up looking boot on the wire right. So if Its not gone when I run it on the lake, I suppose I will order all new wires and a new ignition coil.

Thoughs?

Re: 1997 Larson 186 Losing power and stalling

Have you replaced the filter element in the fuel pump?

Re: 1997 Larson 186 Losing power and stalling

No that I did not do. Althought the pump was new in July of last year.

Re: 1997 Larson 186 Losing power and stalling

DeaconBlues said:

No that I did not do. Althought the pump was new in July of last year.

Click to expand...

Ayuh,... A load of Crud the next day would make that a moot point...

It's worth Checkin'...

Re: 1997 Larson 186 Losing power and stalling

Good point. Its a $15 dollar part. I'll get one on order.

Re: 1997 Larson 186 Losing power and stalling

It dies suddenly, like I reached down and turned the key. No spuddering, no RPM hesitation. I have been leaning toward a problem with the coil, distributer, or something along those lines from the beginning. I agreed with the croud though that it made good sense to check the fuel system first.

I just read the common symptoms to a bad ignition coil, and I swear that is what I am experiencing. But its about $80, so I don't want to jump to that without checking the other stuff first.

Re: 1997 Larson 186 Losing power and stalling

FIXED

So I replaced the wires, distributer cap, and coil. The boat ran awesome.

Thank you all for helping me work through this.