Like Tree0Likes

Formula not up to speed. Help...

Reply
Old 01-31-2010, 08:04 PM
  #21
Registered
 
Join Date: Jul 2005
Location: evansville In
My Boats: '94 29' powerquest
Posts: 482
Default

Easiest First!!!!! Change To Good Known Props!!!!!!!!!!
speedreeder is offline  
Reply With Quote
Old 01-31-2010, 08:13 PM
  #22
Registered
 
Join Date: Oct 2009
Location: Dayton, Ohio
My Boats: Formula 311
Posts: 136
Default

i would double check the timing, and if that is ok, try swaping carbs from one engine to another, to eliminate a carb issue..
theadamv1 is offline  
Reply With Quote
Old 02-01-2010, 03:34 PM
  #23
Registered
 
AIR TIME's Avatar
 
Join Date: Dec 2000
Location: EASTON MA.
My Boats: BAJA OL 650HP/ SABER 28 Gellner unlimited with konrad ace
Posts: 6,281
Default

Quote:
Originally Posted by 336Formula View Post
Bottom of boat is very clean. Up to about 4,000 rpm, throttle is in same position for both engines. When you push up on both throttle levers at same time the port engine revs up to about 5300 and starboard only to about 4700. So you have to back off the port engine throttle to bring it back to 4700 but does not seem like the boat slows down that much.

BTW, thanks for all the attempts so far.
sounds like prop slip
AIR TIME is offline  
Reply With Quote
Old 02-01-2010, 05:17 PM
  #24
Ginger or Mary Ann?
Charter Member
Trade Score: (1)
 
US1 Fountain's Avatar
 
Join Date: Oct 2000
Location: Lafayette. IN
Posts: 10,869
Default

drive showers
__________________
Some people are like Slinkies - Not really good for anything, but they
bring a smile to your face when pushed down the stairs.
US1 Fountain is offline  
Reply With Quote
Old 02-01-2010, 05:32 PM
  #25
Registered
 
Join Date: Sep 2007
Location: Bettendorf, Iowa
My Boats: Baja 24' Outlaw Marine Kinetics Build
Posts: 1,046
Default

Quote:
Originally Posted by AIR TIME View Post
sounds like prop slip
ditto. I had a 21p mirage on my boat for a few minutes after i got my new power in it. the pvs caps were missing and it would get on plane and it would slip when i cracked power to it. it was the incorrect prop i just wanted to see what it would do. i woud switch to known good props and then if that does not work check timing and swap the carbs from engine to engin to eliminate that concern. the beauty of having two engines is that they are great for diagnostics. the ultimate donor.
Fixxxer22 is offline  
Reply With Quote
Old 02-02-2010, 01:29 PM
  #26
Registered
Platinum Member
Thread Starter
 
Join Date: Jan 2010
Posts: 18
Default

We put the drive in forward gear and attempted to turn the prop ccw. Prop would not turn.

Unfortunately the boat is currently on the lift having some touchup paint work being done. And I cannot put it back on water until this weekend.

I have a boat mechanic from a local shop telling me that it is the engine coupler failing. He says that Friday he will pull the engine, replace the coupler and if it does not solve the problem, I owe him nothing. He is very confident in his ability so I guess we will see what happens this weekend.
336Formula is offline  
Reply With Quote
Old 02-02-2010, 01:42 PM
  #27
Registered
 
Join Date: Sep 2007
Location: Essex Junction, Vermont
My Boats: Eclipse 233 sbc 383 dry piped
Posts: 303
Default

Quote:
Originally Posted by 336Formula View Post
We put the drive in forward gear and attempted to turn the prop ccw. Prop would not turn.

Unfortunately the boat is currently on the lift having some touchup paint work being done. And I cannot put it back on water until this weekend.

I have a boat mechanic from a local shop telling me that it is the engine coupler failing. He says that Friday he will pull the engine, replace the coupler and if it does not solve the problem, I owe him nothing. He is very confident in his ability so I guess we will see what happens this weekend.
I like his confidence.
Sunshadow is offline  
Reply With Quote
Old 02-02-2010, 01:43 PM
  #28
Registered
 
Join Date: Jun 2007
Location: Merritt Island, FL
Posts: 3,879
Default

Quote:
Originally Posted by 336Formula View Post
We put the drive in forward gear and attempted to turn the prop ccw. Prop would not turn.

Unfortunately the boat is currently on the lift having some touchup paint work being done. And I cannot put it back on water until this weekend.

I have a boat mechanic from a local shop telling me that it is the engine coupler failing. He says that Friday he will pull the engine, replace the coupler and if it does not solve the problem, I owe him nothing. He is very confident in his ability so I guess we will see what happens this weekend.
If it's a bravo coupler they don't slip. It is a all or nothing. You would see some shavings around it. here's two pictures, one was trashed, prop won't turn at all. The second one is close to failing but you could not tell at all. Worked just like a new one, but not for long.
You can see if the shaft turns it will trash the coupler, no way could it turn the prop and grab at all.
Attached Thumbnails
Formula not up to speed. Help...-dsc_6991.jpg   Formula not up to speed. Help...-dsc_7000.jpg  

Last edited by Wildman_grafix; 02-02-2010 at 02:22 PM.
Wildman_grafix is online now  
Reply With Quote
Old 02-02-2010, 02:11 PM
  #29
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha
My Boats: .......32............. ...............Active Thunder....
Posts: 15,748
Default

Quote:
Originally Posted by Sunshadow View Post
Here's a long shot. Could the upper gears on the port side be worn to the point that they slip (or skip) under the high speed load?
NO. They are either good or trashed. You would here all sorts of grinding and the drive would not do a thing.

Quote:
Originally Posted by 336Formula View Post
We put the drive in forward gear and attempted to turn the prop ccw. Prop would not turn.

Unfortunately the boat is currently on the lift having some touchup paint work being done. And I cannot put it back on water until this weekend.

I have a boat mechanic from a local shop telling me that it is the engine coupler failing. He says that Friday he will pull the engine, replace the coupler and if it does not solve the problem, I owe him nothing. He is very confident in his ability so I guess we will see what happens this weekend.
He may be confident, but not very smart. A coupler may let go slowly............ by slowly, that is a couple minutes at most at higher rpms.. Once it starts to go bad, it takes about 30 seconds before its completely trashed.
Griff is offline  
Reply With Quote
Old 02-02-2010, 02:16 PM
  #30
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha
My Boats: .......32............. ...............Active Thunder....
Posts: 15,748
Default

Things that need to be done.......................
Verify tach accuracy and speed accuracy
Check timing on both engines
Try a known good set of props
What are the drive gear ratios????

The boat should run about 40mph at around 3000 rpms
Griff is offline  
Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 08:27 AM.


Copyright 2011 OffShoreOnly. All rights reserved.