EricJRW
Chief Petty Officer
- Joined
- Feb 3, 2010
- Messages
- 488
Since my gut is telling me this is not a prop problem (I've been through 3), I'm posting here in the Evinrude forum. If you deem this to be a prop problem, then please move it to the proper propeller forum (I know there is only one, I just wanted to say "proper propeller).
Overview: After an hour of running or so (might be 2nd or 3rd trip), on various props, the motor suddenly will over-rev. Only backing down to about 3000 RPM will prevent this from occurring.
Anything above 3000 RPM and the over-rev'ing will occur again. At 3000 RPM, the boat is only going 4 or 5 MPH. If I was going to make a car analogy, I would say it sounds like the clutch is slipping. But outboards don't have a clutch that than can slip, or do they?
Motor: 1993 Evinrude 2-stroke 50HP Outboard, Model E50BEETB, Electric Start
Prop: 13 x 11 Aluminum (no idea of make)
Boat: 1993 Lowe 18'9" Aluminum Pontoon Boat
Details:
Bought the boat last June. On it was a pretty beat up prop, but while cleaning out some stowage, I found another prop. Here's the chronological order of my mishaps.
Any ideas what could be causing this? Was I wrong the suspect the prop and is the problem actually with the motor? It's the only logical answer, but since it seems to come only after sustained running, though I have never dropped the boat back in the water after an incident (I meant to this week, but the weather was bad), I don't know what could be the source.
Thank you in advance for your help.
Sincerely,
Eric
PS. Sorry for the length, I'm trying to be as detailed as possible.
Overview: After an hour of running or so (might be 2nd or 3rd trip), on various props, the motor suddenly will over-rev. Only backing down to about 3000 RPM will prevent this from occurring.
Anything above 3000 RPM and the over-rev'ing will occur again. At 3000 RPM, the boat is only going 4 or 5 MPH. If I was going to make a car analogy, I would say it sounds like the clutch is slipping. But outboards don't have a clutch that than can slip, or do they?
Motor: 1993 Evinrude 2-stroke 50HP Outboard, Model E50BEETB, Electric Start
Prop: 13 x 11 Aluminum (no idea of make)
Boat: 1993 Lowe 18'9" Aluminum Pontoon Boat
Details:
Bought the boat last June. On it was a pretty beat up prop, but while cleaning out some stowage, I found another prop. Here's the chronological order of my mishaps.
- The fairly dinged prop was on the boat. One blade also had a "nibble" out of it. Used this prop for several trips (3 ~ 4 hrs each) without incident.
- Found a prop, in better shape, though it had obviously been filed down a bit. Plan was to swap props in the winter and have dinged prop repaired.
- Installed found prop which game me failure #1 on second or third trip (thought maybe this is why the prop was off the boat).
- Installed repaired prop, and it seemed to work fine (1 or 2 trips). In the mean time I had the found prop "re-hub"ed, thinking bad (rubber) bushing.
- Next trip out the repaired prop gave me the same over-rev problem (incident #2). I have the rehub with me, so I install it. Not 30 minutes later, I get the same over-rev problem with the re-hub'd prop (incident #3, same day as #2). So, unless the dinged prop has the same bushing problem (due to age?) as the found prop, AND the repair work was not done right (I don't think so, the propeller shop I used has been around since 1971), logic would indicate the problem is with the motor, not the prop.
Any ideas what could be causing this? Was I wrong the suspect the prop and is the problem actually with the motor? It's the only logical answer, but since it seems to come only after sustained running, though I have never dropped the boat back in the water after an incident (I meant to this week, but the weather was bad), I don't know what could be the source.
Thank you in advance for your help.
Sincerely,
Eric
PS. Sorry for the length, I'm trying to be as detailed as possible.