Tech Wiki

Diesel Engine

The Catalina 34 has had at least three different motors. The

  • M-25, a 3-cyl, 21 hp engine, was installed on the the early models.
  • M-25XP (3-cyl, 23 hp) became standard in 1988.
  • M-30, a 4-cylinder producing 28hp, became an optional engine about the same time and is standard in the Mark II.

All are produced under the Universal Motors brand (now Westerbeke Corporation). Due to lack of available supplies, the factory occasionally installed a Yanmar engine (note: Yanmars are higher-compression engines, which do not require glow plugs).

General

CRITICAL UPGRADES includes a lot of engine information: Critical Upgrades http://c34.org/bbs/index.php/topic,5078.0.html

RESOURCES – good M25 engine information,from a C36 owner

Spares for a Long Cruise

http://c34.org/bbs/index.php/topic,4590.0.html

Bleeding 101 http://c34.org/bbs/index.php/topic,6377.0.html

Cooling

The first part pertains more to C30's with M-25s/Oberdorfer pumps, than to M-25XPs -- but it's interesting background anyway....  The second part pertains to all those with Ob pumps, and is subtitled "Yes, you're right ...but we don't tell customers that." --KWKloeber 15 May 2015 
Thanks to Ken for that one, I'm tired of repeating it. - Stu  5/25/2015 
  • Engine Thermostats
 M-25/XP/XPA; 35/A; early M-25XPB (to March 1998) use these 38mm diameter thermostats:  160* F - Universal p/n 301358 or Kubota p/n 1E399-73010 (replaces 19203-73014, 19203-73013, 19203-73010.)  180* F - Kubota p/n 15531-73014 (replaces 15531-73013, 15531-73011.)  38mm Gasket - Universal p/n or Kubota p/n 16851-73270 (replaces 15676-73270, 15531-73270, 15676-73272.)    Later M25-XPBs (after March 1998) 44mm 160* F thermostat  Universal p/n 201001 or Kubota p/n 19434-73014 (replaces 19434-73010, 19434-73013)  44mm Gasket - Universal p/n 298843 or Kubota p/n ?    See Service Bulletin #107, Kubota Tstats likely won’t have a bypass hole, so drill a 1/8” hole, or two, thru the inside edge   of its flange so there is a constant coolant flow thru the exhaust manifold when the Tstat is closed. 

Electrical

Exhaust System

The hot exhaust gases are mixed with cooling water in the exhaust elbow and water muffler on their way to the exhaust outlet in the stern of the boat.

Fuel

Mechanical

[NOTE] The filter interchanges at the above OTT website can't necessarily be trusted; double-check if you use them.  For instance, OTT lists NAPA p/n 3389 for both fuel and lube application.  I brought this to OTT's attention and suggested they correct its list.  OTT asked ME to provide THEM all the correct interchange numbers  nd they would revise the website.
I don't THINK so.  :-) --KWKloeber 21:33, 29 June 2014 (PDT)

Transmission

Misc Projects

  • Options to Route Crankcase Breather Hose to Air Intake VIEW THE PDF – K KLoeber May 2015

Shaft & Propeller

Also of Interest

Westerbeke/Universal now has the owner manuals online. You can download them at http://www.westerbeke.com/Products/OnlineManuals.aspx

Kubota Block Equivalents (you have to scroll down) http://www.ericsonyachts.org/infoexchange/showthread.php?10241-Universal-5432-amp-M40-engine-information&highlight=kubota+block

and

http://c34.org/bbs/index.php/topic,8113.msg56648.html#msg56648