Bertram31.com General Bulletin Board

Improved RPM's

Posted By: Paul J
Date: Monday, 5 December 2005, at 8:49 a.m.

I have GM 350 ci, 260hp's with about 800 hours in my B28. Bought the boat in February 2005 (very cold). Had it surveyed in February and sea trials showed both engines turning ~4100 RPMs.

In August I found the motors running hot (~195 - 200) and replaced the risers and rebuilt water pumps. Also did a major tune-up. Cooled things down to ~175-180 on both during full run. Sea water temps were ~85 degrees. During my sea trials and offshore runs in Sept - Oct, I couldn't get them to turn over 3700 RPMs. Thought something was wrong.

This weekend FL temps droped below 40 degrees. Water temps around 65 degrees. Engines now running ~165 and RPMs are able to run up to 4200.

Does engine temp have an effect on top end RPMs? Is there something else going on here?

Messages In This Thread

Improved RPM's
Paul J -- Monday, 5 December 2005, at 8:49 a.m.

Re: Improved RPM's
Ken -- Monday, 5 December 2005, at 8:49 p.m.

Re: Improved RPM's
Capt. Dave Kosh -- Tuesday, 6 December 2005, at 11:15 a.m.