AQ125 not going beyond 2000 RPM under load

[redpanda07]

Hi,
I have a bayliner 20 feet with Penta AQ125 and 280 outdrive in it. The the boat runs fine on driveway without load but in the lake it does not go over 2000 RPM. I got the card redone, new spark plugs with new wires, new coil, exhaust manifold is cleaned, fuel pump is good as well. Can you please help, Could it be timing of the distributer ? or prop(right now I think it 15x19 prop.)

 

[kenny nunez]

Did the engine turn up the maximum rpm before? Is the propeller the one that has always been on the boat? How long have you had the boat?

 

[redpanda07]

Did the engine turn up the maximum rpm before? Is the propeller the one that has always been on the boat? How long have you had the boat?

I recently purchased and never ran it in the water and the prop came with the boat. It goes up to 6000rpm without load but not in the water.

 

[kenny nunez]

If my memory is correct a 15X15 propeller should be on the drive. Volvo can have either a left or right hand propeller so be sure to get the correct one.

 

[ThomW]

If you are only getting 2000 RPM's on the water, I don't think it is a prop issue. Even dropping from a 19 to 15 pitch won't get you were you need to be. Does it seem to idle fine in the water? It very well could be a timing issue.

 

[redpanda07]

If my memory is correct a 15X15 propeller should be on the drive. Volvo can have either a left or right hand propeller so be sure to get the correct one.

I changed the prop to a smaller one that came with the boat and changed the air filter as well. Will try today.

 

[redpanda07]

If you are only getting 2000 RPM's on the water, I don't think it is a prop issue. Even dropping from a 19 to 15 pitch won't get you were you need to be. Does it seem to idle fine in the water? It very well could be a timing issue.

Yes, it idles fine and start in half key turn. it accelerates as if its going to reach 40mh, I mean it pick up the speed quick but feel like it hits the wall at 2000 rpm.

 

[Scott Danforth]

It's never the coil

However it could be the points. What did you set the dwell to? Did you adjust timing?

 

[redpanda07]

It's never the coil

However it could be the points. What did you set the dwell to? Did you adjust timing?

I feel its a little off, I will look at it today.

 

[redpanda07]

I feel its a little off, I will look at it today.

Update: I took the boat yesterday with a smaller prop, carb rebuilt and engine timing adjusted to 10 degrees at 1000 rpm but unfortunately nothing changed. The engine started misfiring at higher RPMs, I put it back to 30 degrees and its working fine again but still not going above 2000 RPM.

The only 2 thing I am doubting is now is the fuel and fuel pump, But again the fuel is running fine in driveway where the boat goes up to 6000 rpm and I feel the pump is also ok as I saw the nozzles were pushing a lot of fuel in carb on WOT.

 

[Scott Danforth]

Update: I took the boat yesterday with a smaller prop, carb rebuilt and engine timing adjusted to 10 degrees at 1000 rpm but unfortunately nothing changed. The engine started misfiring at higher RPMs, I put it back to 30 degrees and its working fine again but still not going above 2000 RPM.

The only 2 thing I am doubting is now is the fuel and fuel pump, But again the fuel is running fine in driveway where the boat goes up to 6000 rpm and I feel the pump is also ok as I saw the nozzles were pushing a lot of fuel in carb on WOT.

what is your dwell set to?

file points
adjust point dwell
then set timing, in that order

 

[redpanda07]

what is your dwell set to?

file points
adjust point dwell
then set timing, in that order

Yes, I set the roter to the first cylinder and cleaned the points and all other contact in the cap. To my surprise the engine is running 30 degrees at 1000 rpm, when I reduced that to 10 degrees it started misfiring. not sure why its happening.

 

[Scott Danforth]

Yes, I set the roter to the first cylinder and cleaned the points and all other contact in the cap. To my surprise the engine is running 30 degrees at 1000 rpm, when I reduced that to 10 degrees it started misfiring. not sure why its happening.

and what did you set the dwell to? (3rd time asking)

 

[redpanda07]

and what did you set the dwell to? (3rd time asking)

I will be honest, I have never even heard of this term before. But I did some googling and now I know it . So obviously I did not touch it, but ordered actron CP7677 and going to use it tomorrow or do you think upgrading to a electronic system would be better.

 

[captmello]

does the motor have the original timing belt, tensioner? if you can't get the timing to adjust correctly, it may need a belt and tensioner. the automotive equivalents are ok to use, and much cheaper.
the dwell is the points gap adjustment. the dwell meter gets it right on. once the dwell is set, then set the timing.

 

[kenny nunez]

Sierra Marine has an electronic conversion which is better than points since the parts are not affected by moisture and the dwell is always steady.
Sierra # 18-5292
For Bosch distributor #0231178017. Just check the number on your distributor.

 

[redpanda07]

does the motor have the original timing belt, tensioner? if you can't get the timing to adjust correctly, it may need a belt and tensioner. the automotive equivalents are ok to use, and much cheaper.
the dwell is the points gap adjustment. the dwell meter gets it right on. once the dwell is set, then set the timing.

The timing belt is new and the tensioner looks good too. I will check the gap, there are kits for converting the point to electronic. what do you think about it.

 

[redpanda07]

Sierra Marine has an electronic conversion which is better than points since the parts are not affected by moisture and the dwell is always steady.
Sierra # 18-5292
For Bosch distributor #0231178017. Just check the number on your distributor.

I have a volvo penta AQ125 and I found people using this one

PerTronix 1146A Ignitor for Delco 4 Cylinder. https://www.amazon.ca/gp/product/B000JUXGAC/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1​

 

[captmello]

The timing belt is new and the tensioner looks good too. I will check the gap, there are kits for converting the point to electronic. what do you think about it.

I had concidered going to electronic ignition but ince I got my points and timing adjusted properly, it didn't seem necessary. I still have points.
they both work. have you done a compression test?

 

[redpanda07]

I had concidered going to electronic ignition but ince I got my points and timing adjusted properly, it didn't seem necessary. I still have points.
they both work. have you done a compression test?

Updated to the electric ignition and changed the fuel pump as well. after doing so much of work I finally realized that the engine is all good its the outdrive. Its a V8 outdrive and mine is a 4 cylinder. now I am looking for an outdrive that i compatible with my more. may be a 270, 275 or a 280.