No acceleration!

[Dandydan]

Boat is a 1994 Sea Sport, with a 302 Ford with a new long block last summer, which I installed myself. It drives a Volvo Penta DP C-1. It has been running very good for several outings now that the bugs have been worked out, until the last couple of trips. Now we are having issues of another nature. They started like this..
It seems that after an extended period of no wake speed, or with a cold engine, when able to accelerate, and shoving the throttle lever forward, the engine does not want to respond. I thought I had dirty fuel filter issues and changed them out, finding that the filter did its job and there was a fair amount of water/dirt in the filter. In the past, after a brief period, (30-45 seconds) the engine took off and ran normally, the boat came up on a plane, and all was well. Cause for concern, but not to panic.
Today, after running out through the no wake zone, when the throttle was engaged, the engine sped up, but the boat did not. It was like the prop was not engaging, so I’m thinking the outdrive is messed up. The RPMs were up over 4000, but the boat did not speed up at all.
I have included the recent operational history, because the results are similar in nature, though I am not sure they are related. I am mostly concerned with what seems to be a slipping clutch type problem but don’t really know how to diagnose that issue.

 

[Fireman78]

I don’t know much but could be a spun prop

 

[Dandydan]

Thank you for the response. Well I wonder if that is it. It is a Duo Prop and I don’t know if there is a rubber hub in there. I checked the oil and it is fine. Thanks alot

 

[Fireman78]

Some duoprops are rubber hubbed. If there’s no water in the oil that could be it

 

[Dandydan]

I appreciate your input. I am rather hoping it is a spun hub. I am due for a new prop anyway. My existing prop has a few lumps and bruises. It is probably the original, which would make it about 25 years old.

 

[Dandydan]

I pulled the props. They are indeed rubber hubbed. Or course you cant tell by looking, but they seem pretty rugged looking. Like maybe they have spun. Good call. I will let you know when i get some grease for the prop shaft. Then test it out!

 

[Sparkinator]

Mark the rubber bushing and and prop so you can see if it slipped. Also, how did the engine coupling look when you changed the engine?

 

[Scott Danforth]

your DP-C will have rubber prop hubs. only about 2-3 places left in the US that will repair them

do you have the shift linkage adjusted correctly?

use the same grease you put in your axle bearings on your prop shaft

 

[Dandydan]

Many thanks to all of you who responded. Indeed it seems to to be the hub as the new Volvo Penta props I installed pushed her right out of the hole and up on the top. Ran great all day except for that little annoyance of the engine not picking up RPMs when it is cold. When accelerating for the first time after fishing all afternoon on the new 4 cycle kicker, it runs up to about 1500 and just stays there for maybe a minute. Then it seems like it figures out it is supposed to be going and with no further fiddling with throttle lever, it accelerates up to where its supposed to be and runs great. It does not do the same thing on subsequent start ups while the engine is warmed up. Choke? Other ideas? I will start a new post soon.