Stern Drive Mystery

[rtoedtman]

Recently pulled my Sea Ray 185 out of storage. Dropped in the battery checked the fluids and set it up for a dry land start. Turned over just fine and started. Allowed the engine to come up to temperature and all seemed great. Put the boat up for sale and sold it. The new owner has come to me now indicating that when he took it out for the first time the engine started and ran up the rpm's normally. However when he put the drive in gear and attempted to bring the boat up to speed it would only run no more than 5-10 mph. If anyone has any idea what might be the problem I would appreciate your reply. Thanks.

 

[nola mike]

Recently pulled my Sea Ray 185 out of storage. Dropped in the battery checked the fluids and set it up for a dry land start. Turned over just fine and started. Allowed the engine to come up to temperature and all seemed great. Put the boat up for sale and sold it. The new owner has come to me now indicating that when he took it out for the first time the engine started and ran up the rpm's normally. However when he put the drive in gear and attempted to bring the boat up to speed it would only run no more than 5-10 mph. If anyone has any idea what might be the problem I would appreciate your reply. Thanks.

Likely fuel related, would start by checking the filters. Although we have no idea what's pushing the boat

 

[rtoedtman]

Likely fuel related, would start by checking the filters. Although we have no idea what's pushing the boat

Thanks for your reply but it doesn't explain why you can rev the engine up out of gear yet when in gear it won't rev up allowing the boat to come up to speed.

 

[Chris1956]

Engines will rev up just fine in neutral, with dead cylinders, partially clogged filters and antisiphon valves, bad spark advance, bad spark plug wires etc. Neutral testing RPM is meaningless, as it requires little power.

 

[Scott06]

Recently pulled my Sea Ray 185 out of storage. Dropped in the battery checked the fluids and set it up for a dry land start. Turned over just fine and started. Allowed the engine to come up to temperature and all seemed great. Put the boat up for sale and sold it. The new owner has come to me now indicating that when he took it out for the first time the engine started and ran up the rpm's normally. However when he put the drive in gear and attempted to bring the boat up to speed it would only run no more than 5-10 mph. If anyone has any idea what might be the problem I would appreciate your reply. Thanks.

As mentioned by others reving in neutral doesn't mean anything. This is why they always recommend doing a water test under load. Of course as the seller I wouldn't insist on it ... last time I sold a boat he didnt even ask me to start it.

How long did it sit? Could be contaminated fuel gummed up carb, or ignition issues (are they points) . What year and what engine ?

 

[racerone]

Agreed---revving an engine in neutral means nothing.-------Is the buyer trying to get a bit of a discount now ?-----Do you feel the buyer is honest here.

 

[nola mike]

Thanks for your reply but it doesn't explain why you can rev the engine up out of gear yet when in gear it won't rev up allowing the boat to come up to speed.

It does though. Check your fuel system

 

[racerone]

In gear on muffs is still neutral as the prop does no work moving air.------In the water the prop puts a load on the engine.----If the motor is in poor shape ( needs tune-up ? ) it can not do the work.-----An 200 HP engine does not produce 200 hp while idling.----It only produces enuff power to keep itself running !------

 

[tpenfield]

I'd be cautious in taking on the new owner's issue. Not your problem anymore unless there is some sort of warranty that may apply to the sale.

As stated revving in neutral means nothing.

 

[rtoedtman]

Agreed---revving an engine in neutral means nothing.-------Is the buyer trying to get a bit of a discount now ?-----Do you feel the buyer is honest here.

Just asking to help him with the problem. No money just advise.

 

[rtoedtman]

As mentioned by others reving in neutral doesn't mean anything. This is why they always recommend doing a water test under load. Of course as the seller I wouldn't insist on it ... last time I sold a boat he didnt even ask me to start it.

How long did it sit? Could be contaminated fuel gummed up carb, or ignition issues (are they points) . What year and what engine ?

Sat from Nov 2023 to Mid March 2024.
Only use non ethanol fuel.
1999 and 4.3L EFI Alpha I MCM (210 hp)

 

[Dillusion808]

Just start with the easy stuff.

Hook up a couple gallon tank with fresh gas.