Cruisers Forum

Join CruisersForum Today

Thread Tools Rate Thread Display Modes
Old 17-05-2015, 05:11   #1
Registered User
dardurfr's Avatar

Join Date: Jun 2013
Location: Newfoundland, Canada
Boat: 30ft Homemade Cabin Cruiser fg/w - Perkins 4-154 62hp
Posts: 8
Transmission Replacement

I got a Perkins 4-154 62hp thats approximately 30-40 years old and works like a charm. The transmission(gearbox) is 2.91-1 reduction. I have no proof how old the trans is because the plate is no longer on it but figure it might be same has the engine. I'm thinking of replacing it with a 2.57-1 reduction. I know this will give me more rpms on the prop but wondering if it will cause any issues with the engine. Any thoughts?
dardurfr is offline   Reply With Quote
Old 17-05-2015, 06:39   #2
Senior Cruiser
Sailmonkey's Avatar

Cruisers Forum Supporter

Join Date: Sep 2009
Location: Houston
Boat: '76 Allied Seawind II, 32'
Posts: 6,232
Re: Transmission Replacement

It should only cause you problems with the engine if you keep the prop that was matched to the 2.9 gearbox. If you re prop for the new trans you'll be just fine.

Sent from my iPhone using Cruisers Sailing Forum
Sailmonkey is offline   Reply With Quote
Old 17-05-2015, 07:56   #3
Registered User

Join Date: Feb 2013
Location: Lago de Izabal, Guatemala
Boat: Seafarer36c
Posts: 4,390
Re: Transmission Replacement

It should give you about another 100rpm on the prop? Sounds like a lot of money for such a small gain. If you re-pitch the prop you will put more load on the engine and it's kind of old now for changing things.
Ecos is offline   Reply With Quote

men, transmission

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Replacement aluminum Yanmar transmission dipstick cap/tube bobatkins Commercial Posts 1 24-07-2017 14:38
Paragon Transmission replacement taiskwa Engines and Propulsion Systems 3 20-02-2015 17:04
Transmission Rear Seal Replacement boeing1 Propellers & Drive Systems 7 23-12-2014 09:56
Tips for DIY Transmission Replacement 4arch Engines and Propulsion Systems 6 23-10-2014 16:25

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 15:05.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.