AQ131C w/ SP-CD rattling at WOT

[retriever]

I have an AQ131C w/ SP-CD drive on a 1989 Sportcraft Sprint 1900 CC. We have had the boat for 3 seasons now. The first Summer we worked out the normal bugs due to the boat sitting for a few years. The first Winter we had the gimbal replaced and last Summer we replaced some soft spots in the floor and recarpeted. I was hoping for a problem free summer and as many weekends on the water before baby #2 comes in late August but yesterday we were pulling my niece in a tube and I heard a rattling sound coming from the engine compartment. I looked back and saw an empty soda can in the cup holder. The first chance I got, it went in the trash and we continued tubing. I heard the noise again and slowed down, it went away. We pulled the tube in and I began to trouble shoot, neutral - no noise, low throttle - no noise, WOT - noise. We made it back to trailer and after getting home checked the drive and motor oil - both clean, no water or shavings. There was a little air pressure in the drive that escaped when I loosened the screw but that was the only odd thing I noticed. Pulled the spark plugs thinking a piston or valve might have been hitting - all 4 were dry and clean with no signs of contact. I am a little gun shy because I recall a similar sound prior to the gimbal going 2 seasons ago. Can anyone give me some advice on the next step, what should I check or am I just paranoid and need to enjoy the water while I can for the year?

Thanks in advance for your expertise.

 

[captmello]

Re: AQ131C w/ SP-CD rattling at WOT

Is it possible the prop is bent or beat up just enough to cause a vibration? Does it vibrate in nuetral while giving throttle? Need to isolate the problem.

 

[Don S]

Re: AQ131C w/ SP-CD rattling at WOT

I recall a similar sound prior to the gimbal going 2 seasons ago.

Not sure what was replaced, but your drive does not have a "Gimbal" assuming you meant gimbal bearing.
If you are referring to the bearing in the flywheel cover, did the bearing fit tight in the housing? if not, the bearing may be rattling around in the housing.
or you may have ujoint problems. Was the ujoints checked and was there water in the bellows before? Was the bellows replaced?

 

[rbh]

Re: AQ131C w/ SP-CD rattling at WOT

Could your valves be rattling due to timing being out???

 

[retriever]

Re: AQ131C w/ SP-CD rattling at WOT

Thanks for the quick responses... The prop is in great shape so I will rule that one out, the gimbal bearing was replaced by a local shop. The exhaust and drive bellows were both replaced and yes there was water in the oil. I am not sure about the u-joints but did not have this noise all last year after the work was completed. It might be worth checking the timing but would it be different when running WOT on the water in gear from running WOT in neutral on ears in the driveway?

Thanks again -

 

[fishinpa]

Re: AQ131C w/ SP-CD rattling at WOT

Yes it could be very different!

Also WOT on the muffs is def not a good idea.
wondering if your valves or more arent rattling after reading above !


fish