200 hp yr 2000 lower unit rebuilt

[fatfrank]

Just had my lower unit rebuilt and after six long weeks put boat back in water. Used to plane at 3M r p m cruise at 4m r p m. Now it doesn't plane until I get to 4m R P M and wot is, get this, 7m R P M. Supposed to be governed at 6000 R P M. Won't take it back to the liars who rebuilt it and charged me enough to buy a new lower unit. Boat runs great at 4m rpm and above, worried about running to hot. Any suggestions? 24' wellcraft/hrd top

 

[Hooty]

Re: 200 hp yr 2000 lower unit rebuilt

This is just an idea but look at the back side of the tach and make sure the selector switch is set on "6". The "6" is not for six cylinders, it's for six pulses from the alternator.<br /><br />c/6<br />Hooty

 

[fatfrank]

Re: 200 hp yr 2000 lower unit rebuilt

Thanks Hooty for the tip I will check that out.<br />Apparently though after four seasons my prop has started to slip on the hub which results in sluggish acceleration and run away at wot. Hasn't fully broken lose yet but very close. The rebuilders said they tested the boat in open water but I really doubt that because soon as I put it in the problem occured. New hub being pressed on as I type will let you know results.

 

[Hooty]

Re: 200 hp yr 2000 lower unit rebuilt

Slippin' hub? That makes sense. Hope tha new hub takes care of it for ya.<br /><br />c/6<br />Hooty

 

[fatfrank]

Re: 200 hp yr 2000 lower unit rebuilt

Originally posted by fat frank:<br /> Thanks Hooty for the tip I will check that out.<br />Apparently though after four seasons my prop has started to slip on the hub which results in sluggish acceleration and run away at wot. Hasn't fully broken lose yet but very close. The rebuilders said they tested the boat in open water but I really doubt that because soon as I put it in the problem occured. New hub being pressed on as I type will let you know results.

 

[fatfrank]

Re: 200 hp yr 2000 lower unit rebuilt

still not planning off at 3000 like it used to<br />even with new hub in ss prop ? ? ? ?

 

[Dhadley]

Re: 200 hp yr 2000 lower unit rebuilt

Whats the tach set on?

 

[fatfrank]

Re: 200 hp yr 2000 lower unit rebuilt

tach was not touched original settings from new only 4th season in water and short seasons at that

 

[fatfrank]

Re: 200 hp yr 2000 lower unit rebuilt

I believe that they installed wrong gear. Different gear ratio...checking out part # installed.

 

[Dhadley]

Re: 200 hp yr 2000 lower unit rebuilt

Regardless of the gear ratio the motor wont turn 7000 rpm unless they unhooked the rev limiter.<br /><br />Lets do the simplist thing first and look at what position the tach is set on.

 

[rodbolt]

Re: 200 hp yr 2000 lower unit rebuilt

I am kinda with Dhadley here. its odd to get that much RPM out of it. but I did a merc 115 inline a few years back.replaced the gearcase and the man came back saying I had messed up his motor cause it would only turn 2300. after much knashing and thrasing we discovered that somewhere some one had replaced the gear set with a 4cyl set with a 2.4 ratio and I had replaced it with the correct 2.0 ratio so the prop was now way to big. was it my fault that I repaired the motor with the correct factory parts? was it the last guys fault for frankenstiening it? could also be that the correct parts are in place now but not before. If I were you I would take it back and explain what is happening and that it no longer runs like it did. I am not a god(no matter what the wimmins thank) I am a technician. your the one who has to tell me if something is different this time compared to last time. or it could be like my OMC tach sometimes I look down and its sitting on 7k, a quick rap on the cystal with a knuckle makes it go back to 4800.Dhadley is steering ya in the right direction. check the easy simple stuff first. tachs dont last forever.

 

[fatfrank]

Re: 200 hp yr 2000 lower unit rebuilt

thnx will check out the tach..factory says they are the correct gears..with rehubbed prop no longer runs to 7m but to proper 6250 at wot..one problem solved at least

 

[Dhadley]

Re: 200 hp yr 2000 lower unit rebuilt

Are you sure you have your original prop? Even at 6250 you might be on the limiter if its at 6200.

 

[fatfrank]

Re: 200 hp yr 2000 lower unit rebuilt

yes same original prop boat is now "loaded with full 99 gallons of gas" once i burn some fuel off it might perform better..ugh..this is really got me going. Talked to a guy at the dock who has the exact same set up, becuase I thought I was wrong but he confirms boat plains out between 2500 to 3000 rpm That is what mine used to do.

 

[fatfrank]

Re: 200 hp yr 2000 lower unit rebuilt

Well you guys were right..instrument cover was tampered with and I found that the tach switch was not where it should be...it was between 6 and 4. When I reset the thing to 6...boat runs great now. Now I just have to catch some fish ! ! !

 

[Dhadley]

Re: 200 hp yr 2000 lower unit rebuilt

Glad ya found it. Makes a person wonder whay they went to all the trouble to mess with that setting??<br /><br />Good luck!!