volvo aq125 loses power after a few min.

[tevans720]

I have been working on a 83 bayliner. It was over heating so we changed out the impeller. Someone put in the wrong one. It still heats up but not for a while and only at WOT. I think I might have narrowed it down to it pulling air in. Will put a clear hose on to check.

The other problem is we push the throttle wide open and she only runs at 3500. I'm guessing it should run about 4500. After it runs at 3500 for say 3 min or so she loses all power and backs down to around 2000 1500. If you back off to idle for a min or so and back to WOT it will go up to 3500 again but after a few min right back down again.

I have no idea what it could be. Maybe a good carb cleaning not sure. Your thoughts would be greatly appreciated.

Thanks

 

[freeboats]

Re: volvo aq125 loses power after a few min.

I would look farther upstream than the carb.,

try changing out the fuel filter, I put an inline clear filter so I could see.

drain the old fuel. and look in the tank to see if there is anything gross in there or mabey some water.


I have the same boat and had the same issue last year

 

[tevans720]

Re: volvo aq125 loses power after a few min.

Yea was thinking it was something with the fuel. My buddie says he has a bad feeling its loosing compression. I don't think so what you all think? Should I keep on the fuel idea or move over and test compression?

 

[bruceb58]

Re: volvo aq125 loses power after a few min.

Probably fuel related. Could be a tank venting issue. Get a portable tank and run from that to see if you have the same problem.

 

[Fishermark]

Re: volvo aq125 loses power after a few min.

What he said. ^^^^ I would second the fuel tank vent being the problem.

 

[tevans720]

Re: volvo aq125 loses power after a few min.

ok will try to see what we can get done today. It's raining here so not sure if I will get to work on it. How do I go about finding the vent in one of those inboard tanks? I'm used to out boards first time working on a inboard.

Thanks

 

[bruceb58]

Re: volvo aq125 loses power after a few min.

ASa quicky test, you can try running with the gas cap off. The vent goes to a fitting at the side of the hull. Often it is also near the gas cap.

 

[tevans720]

Re: volvo aq125 loses power after a few min.

O OK yea I remember where it is now! Brain fart LOL.

Thanks again I will try to get to it tonight.

 

[mcleaves]

Re: volvo aq125 loses power after a few min.

Don will love me for posting this.

Check all your fuel line connections. Make sure the clamps are tight and the hose is not collapsing. I had a similar problem years ago with my 125. Turns out it was pulling just enough air in at the tank fitting. to keep form from going over 3500. Of course when Don told me to check ALL the fitting I didn't think he really meant ALL. After a month of chasing my tail 1 turn of the screwdiver solved my problems

At any rate it sounds like a fuel problem to me and all the other advice about checking the fuels system is good as well.

BTW it never hurts to check compression if for nothing else it provides a baseline year over year. But I don't think compression would affect you the way you describe

-M

 

[tevans720]

Re: volvo aq125 loses power after a few min.

Still havent got to it the 2 kegs got in the way last weekend. Now its just too damn hot was 95 and humid yesterday.

As soon as we get to it I will post my findings.

Thanks again.

 

[tevans720]

Re: volvo aq125 loses power after a few min.

Well got it out this weekend to try it out. Took the gas cap off and ran it still the same only to 3500rpms. So we poured Seafoam right in the carb little bit a few times while running it at 2000rpms then a bunch till she killed. We waited about 5 min then started it back up. She smoked like hell for a bit then got it up to 4000rpms.

So I think we just need a good carb cleaning or even a rebuild and we should be fine for that problem im guessing. All the lines look a little rough so gonna replace them and put in a inline fuel filter as well.

Its still pouring coolant out of the cap what is that all about? we replaced the cap and still the same. It only does it when going over 2500rpms. Not sure if this has to do with the overheating or not. After the impeller change it takes quite a long time to heat up but it will get to about 220f 230f and when at idle she will cool off quickly. Right below the strainer housing(I think thats what its called) where it meets that other housing it leaks a little bit of water just a tiny bit could that be a issue?


Thanks for the help