Reply
 
Thread Tools Search this Thread Display Modes
 
Old 07-20-2023, 01:21 PM   #1
Lt. Commander
 
Join Date: Apr 2019
Posts: 112
Default Engine swap 4.3L to 4.5L

Howdy forum..

Looking to swap the engine in a 2001 Maxum 1800sr from a 4.3L to 4.5L however the dealer is not comfortable putting in a 250HP. Dealer mentioned the gear ratio of the A1G2 wouldnt be able to handle it.. Its 1.8 so thats fine.. Then mentioned A1G2 wouldnt be able to handle the extra HP.. Said that was BS as its rated to 300HP.. Then said the hull wont be able to handle it and unfortunately I dont have any documentation or anything solid to say it can..

Does anyone know what I can say here? I rang mercruiser support and they said 50hp doesnt make that much of a difference and should be fine.. however recommended I contact the boat manufacturer

Any advice would be very much appreciated.
__________________

__________________
Proud owner of a 2001 Maxum 1800SR.
Engine: 2023 Mercruiser 4.5L 250HP
Outdrive: Alpha1 Gen2 with 1.6gear
Keen interest in anything electronic or gadget related!
fester is offline   Reply With Quote
Old 07-20-2023, 03:34 PM   #2
Admiral
 
mmwjr's Avatar
 
Join Date: Feb 2012
Location: Essex, Maryland
Posts: 11,058
Default

What gear ratio does mercruiser recommend? Yes the Alpha is rated for 300 HP. IMO the extra horsepower shouldn’t be and issue especially since you don’t run at that peak power regularly.
__________________
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2

Mike
mmwjr is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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 Off
Pingbacks are Off
Refbacks are Off


» Popular Tags
3.0 4.5 1994 1995 maxum 2000 maxum 1900 2003 maxum 3300 2007 2600se 2100sc 2800 scr 2800scr air in water lines basic service bilge pump bimini bimini top boat engine boise idaho bow thruster cabin heater canvas convertible top cooling cover for ladder damaged electrical excellent cond fool front locker fuel consumption fuel economy fuse block fuse panel fuses galley galley sink gas strut glass glovebox hardware harness highfield 310 hinges hurley latches leaks maintenance manifold manual 2300sr maxum 2400 scr maxum letters mercruiser 4.3 mercruiser shift switch navigation lighting no possible way oil change screw a light here... seals servicing ski locker hatch stater thruster transom rear door vacuflush vibration waste pump water in bilge window winterization wiring yacht
Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 08:22 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2026, vBulletin Solutions, Inc.