Can't get over 3000 RPM

[ssurfer24]

1985 Bayliner Capri Cabin Cuddy
Volvo Penta AQ125A with 270 outdrive

So a few weeks ago when I took boat out it was surging a little bit off and on but it went away after a bit. This past weekend I was down to about a quarter tank of gas so I added some 91 octane which brought it up to about three quarters of a tank. Got out on the lake and it started surging a little bit then cleared up. 30 mins later went back to the dock to pick up a 2 more people (4 total). Once loaded I cruised past the no wake part and went to throttle up and couldn’t get over 2500-2800 RPM. I popped the engine cover and manually tried to pull throttle cable to get it to rev up but nothing worked. I went back to the dock slowly and tied up. I can put it in neutral and get full power with no problems but as soon as I put it into gear it bogs down and can’t get RPM up.

So only thing I can think of is that I have a plugged carburetor jet and/or something caught on the propeller shaft that I picked up when loading up at the dock.

On a side note at one lake I was in the spring (first time out this year) at I was cruising around at about 30-35 mph but at this lake (third time) I haven’t been able to get over 25 MPH and now this. The 2 lakes are 30 miles apart in different elevation but not much. At the higher lake I got more speed than lower lake.

Any thoughts on where I should start looking? It will be a few weeks before I can even work on the boat (ankle surgery) but I want to get a game plan so I know where I’m going to look first… or second…

 

[LightningBob]

When you say full power in neutral do you mean that you have it out of gear and you’re manually operating the linkage on the carburetor?
Because if that’s the case I wouldn’t be looking around the carburetor too much but that’s just me.
to me if the carburetor is eliminated from the equation I’d first take a look at the prop like said that would be the fastest thing to do. Makes me wonder if it’s an issue related to one or more of the cables

 

[ssurfer24]

I can get over 4000 rpm in neutral out of gear. I can manually operate linkage with same results. I'll look at the prop first. One of my coworkers thought it might be the high speed jet in the carburator that is plugged. I think it might be the prop but not sure until I take it off. It'll be another week or 2 before I can work on that (ankle surgery)

 

[Bt Doctur]

replace the sparkplugs and wires

 

[LightningBob]

I can get over 4000 rpm in neutral out of gear. I can manually operate linkage with same results. I'll look at the prop first. One of my coworkers thought it might be the high speed jet in the carburator that is plugged. I think it might be the prop but not sure until I take it off. It'll be another week or 2 before I can work on that (ankle surgery)

Yeah check out the obvious first, maybe I’m wrong and someone else can better explain to me but out of gear you’re getting 4K rpm and it’s running normally but in gear it all changes, I just can’t see it being a carb problem then because it’s not a variable.

if you have something binding up your prop that could make sense because it’s only spinning when it’s in a gear and it would probably be fluctuating

if it’s something in the outdrive going out, it would probably be audibly obvious

2nd thing I would do is a visual inspection on your cables?

 

[kenny nunez]

If the carburetor has not been cleaned it would not hurt to go through it. There are some removable plugs that have screens that can be plugged. Most times the gaskets can be re used.

 

[Georgian blues]

I currently have this problem.aq125 with 270. I took apart the outdrive and found a milkshake with a rusty u joint.

 

[ssurfer24]

Still haven't been able to get at this problem. Can't put any weight on my ankle until Sept 7th (wife won't help). Once I take off the prop and look more into the outdrive I should know more.

 

[Georgian blues]

I hope you get it sorted when you get to it. FYI upon further inspection. I found a pinhole in my drive bellow that slowly caused the pds bearing to rust and fail. I'd have the new one in but auto store closed early today.

 

[ssurfer24]

Well I had a new drive bellow installed this spring due to a leak. One thing I forgot to mention before.. So first trip out this year I was doing fine then I hit a sand bar which pulled outboard away from transom about 1/4" at the bottom. Found out one of the nuts was missing that helped hold it in place which is why it pulled away. I fixed that and resealed it with 3M 5200 sealant. Fast forward a few weeks and took it out to a different lake and I had it up to 3500 rpm I believe but wasn't getting over 22 mph which was strange but it was really choppy that day so I didn't think to much about it. The 2nd time I didn't take it out very long as wife just wanted to go swimming off the back so we just farted out there and farted back in. 3rd time is when I really noticed it and 4th time I couldn't get it running good at all. I want to pull off that propellor and look at that and what's behind it. I want to get a new prop but am unsure what size I need. Any ideas? I found the volvo propellor guide online but there are so many to choose from. I'm not sure the specs on the prop currently installed...