Spun prop or bad engine coupler?

[boatinkansas]

I just bought a 94 Bayliner 185 merc4.3 alpha 1 and took it out to the lake this weekend and out of the hole it was alright tell i started to plane out then my rpms would jump to 5200 if i didnt let off quick. redline is 4600 in the boat. If i get weight in the front it will plane a little better but still not great. Every time it over revved the trim was all the way down or just a little above. The prop is a quicksilver laser 2 19 pitch, elevation is 2000ft. I didnt smell any burning rubber from the engine but may have a slight vibration at mid throttle. Are the over rev problems a prop or engine coupler.

 

[Bondo]

Re: Spun prop or bad engine coupler?

I just bought a 94 Bayliner 185 merc4.3 alpha 1 and took it out to the lake this weekend and out of the hole it was alright tell i started to plane out then my rpms would jump to 5200 if i didnt let off quick. redline is 4600 in the boat. If i get weight in the front it will plane a little better but still not great. Every time it over revved the trim was all the way down or just a little above. The prop is a quicksilver laser 2 19 pitch, elevation is 2000ft. I didnt smell any burning rubber from the engine but may have a slight vibration at mid throttle. Are the over rev problems a prop or engine coupler.

Ayuh,.... Welcome Aboard,... Put yer spare prop on, 'n Try it,...

if that fixes it, ya found the problem,...

 

[Laser Boat]

Re: Spun prop or bad engine coupler?

Help, I think my problem goes with this one, direct me else where or new post if needed. I have 1978 Mercury 150hp v6, bought last year. took it out then and it could iddle & slow cruise 5-10mph just fine. Give it throttle and before it could get half way it would loose grip & rev up, like slipping into nuetral. I was told spun prop, took it to prop shop, they said mine was to old and chewed up, they actually just gave me a old replacement prop back in its place for same cost as hub repair $60. i didnt get to go back out until this year. It does the same thing, this prop has brand new hub in it, gear oil is checked & good. Do i have a bad engine coupler? and im sorry buy im new to boating and not mechanic but ive searched & searched, i cant find parts called engine coupler, can you post a diagram and or show / tell me where thats at. Thank you

 

[Laser Boat]

Re: Spun prop or bad engine coupler?

ps I can floor it, giving it wide open throttle and i mean it feels great and shoots up out of the water on top in a hurry but only last 3-4 seconds before its rev's up again and looses all grip, i back off instantly thought when it happens

 

[steelespike]

Re: Spun prop or bad engine coupler?

delete

 

[steelespike]

Re: Spun prop or bad engine coupler?

You should start your own thread there is a big red tab near the top of the prop forum.
What is the diameter and pitch of the present prop.May be under the prop nut.
No numbers; you can measure diameter carefully from the center of the bore to the tip of a blade and double it.
It should be at least 14".

 

[jestor68]

Re: Spun prop or bad engine coupler?

Help, I think my problem goes with this one, direct me else where or new post if needed. I have 1978 Mercury 150hp v6, bought last year. took it out then and it could iddle & slow cruise 5-10mph just fine. Give it throttle and before it could get half way it would loose grip & rev up, like slipping into nuetral. I was told spun prop, took it to prop shop, they said mine was to old and chewed up, they actually just gave me a old replacement prop back in its place for same cost as hub repair $60. i didnt get to go back out until this year. It does the same thing, this prop has brand new hub in it, gear oil is checked & good. Do i have a bad engine coupler? and im sorry buy im new to boating and not mechanic but ive searched & searched, i cant find parts called engine coupler, can you post a diagram and or show / tell me where thats at. Thank you

There is no "coupler" on your outboard motor. What kind of boat is this 150 on?

Check the height of the motor on the transom. The AV(cavitation) plate should be even with the bottom with the motor sitting in a neutral(level) position. Make sure the motor is trimmed all the way down(in) when starting out.

A used prop from a prop shop is a 50/50 chance of being any good. A brand new Solas Rubex is only a few dollars more and will answer the question concerning the possibility of a bad hub.

 

[jestor68]

Re: Spun prop or bad engine coupler?

I just bought a 94 Bayliner 185 merc4.3 alpha 1 and took it out to the lake this weekend and out of the hole it was alright tell i started to plane out then my rpms would jump to 5200 if i didnt let off quick. redline is 4600 in the boat. If i get weight in the front it will plane a little better but still not great. Every time it over revved the trim was all the way down or just a little above. The prop is a quicksilver laser 2 19 pitch, elevation is 2000ft. I didnt smell any burning rubber from the engine but may have a slight vibration at mid throttle. Are the over rev problems a prop or engine coupler.

Any kind of trouble in the drive system would be evident; there would be plenty of noises.

The likely hood is high that you have a bad prop hub. I assume your Laser uses the Flo Torq hub system.

You can replace it with a new Flo Torq hub, or (better yet) with a Solas Rubex # 102 hub.

 

[Laser Boat]

Re: Spun prop or bad engine coupler?

hey thanks guys, i did just go out few minutes ago and started my new thread line on this, might have more info if you could please transfer over to it. titled 1978 mercury 150 v6 balckmax engine coupler

 

[Laser Boat]

Re: Spun prop or bad engine coupler?

ps Jestor, ill go over to my other posting, but in reply about the used prop, it was used prop from them but they had put a new hub in it.

 

[jestor68]

Re: Spun prop or bad engine coupler?

ps Jestor, ill go over to my other posting, but in reply about the used prop, it was used prop from them but they had put a new hub in it.

I don't see your new thread; but the reason I'm asking you to check motor height, trim angle at start up, etc.; is to try and eliminate other possible factors, such as ventilating the prop(which would cause similar results).