UBUC Maintenance Documentation

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Engine Millie is currently working


Other Attributes

Part Attributes
  • colour = Silver
  • manufacturer = Tohatsu
  • mass = 65kg
  • model = M40C
  • newvalue = 2900
  • power = 40Hp
  • propdiameter = 18.5cm
  • proppitch = 11inch
  • serial = 010324XE
  • status = working
  • year = 2005
Engine Operation
Engine Storage
Engine Inspection 2016-02-07 6
Engine Service 2018-04-05 12 200



Date Member Supplier Cost Comment
2018-04-05 Sam Walder Millie Serviced by Chris and Josh (with input from many others)
2017-03-01 UBUC Daemon 200.00 Engine Service; out of date
2016-02-07 Tim Walsh Wet Bristol 250.00 Millie serviced by Simon and Leon, carb, water pump, spark plugs, fuel pump, gear oil all replaced and thermostat checked and operational
2016-02-07 Tim Walsh Wet Bristol Millie is missing a fuel clip (ref 5-11, partno 338-02215-0), nut (ref 8-19, partno 930113-0800), clamp (ref 8-20, 309-06972-0), Choke Bush (ref 4-14, 345-67195-1) and has problems with the starter handle missing O-ring (ref 11-1-23 partno 350-05136-0), rope anchor (ref 11-2-22, partno 338-05131-0), plate rope anchor (ref 11-1-24, partno 345-05134-0). The thread is going in one of the around the M6 studs holding on the carb. Float pin mount still broken
2015-09-22 Tim Walsh 350.00 There are some issues outstanding from the record of 2014-12-07, namely 1) The broken mount for the float pin rectification is a new carb (Part No 345-03200-0) likely cost 200 2) The cross threading of the lower spark hole requires new cylinder head gasket (Part No 345-01005-0) likely cost 60 3) The missing parts from the pull cord handle likely cost 25 4) There is also an outstanding question as to whether the tiller arm meshing issues have been fully solved or whether the engine mounts (part nos 345-61301-0, 345-61302-0) (17-27 & 17-33 in parts list) needed inspection
2015-09-17 Hayley
2015-05-08 Hayley McLennan The fuel pipe between the filter and pump that was shortened on the maintenance course was replaced in Jan/Feb (Part No 98AB-5-0270)
2015-03-08 Tim Walsh Engine performed flawlessly on boat handling course
2015-02-24 chris coltman killcord switch replaced, needs testing. linkage snap clip replaced.
2014-12-08 Tim Walsh Millie should operate at 5000 rpm (Engine Manual pg12). The calculation of 11 inch propeller pitch * 5000 rpm translates to a boat speed of around 45 kts. When the speed of quite lightly laden boats was recorded on the last boat handling course, neither boat exceeded 12 kts. This suggest that a lower geared prop might be more performant. Ruby has a 7inch prop and we have spare 5 inch props so should to do a systematic investigation.
2014-12-07 Tim Walsh The On/Off lanyard switch (Part No 398-06830-0) is not functioning properly - Duncan had to bypass it to start the engine. Within the carb body, the mount for the float pin has broken on one side and we may soon need to replace the carb (Part No 345-03200-0). A rod snap clip 345-05223-1 needs replacing on the gear interlock. To fix a fuel leak the fuel pipe between the fuel filter and fuel pump was shortened (Part No 98AB-5-0270), this pipe has an o.d. of 10mm and an i.d. of 6mm. The lower spark plug hole has been cross threaded this can be repaired in workshop, but the task will removal of the cylinder head and replacement of the cylinder head gasket (Part No 345-01005-0). The pull cord handle is missing some sub components - partnos(350-05136-0, 345-05134-0, 344-05116-0). Duncan proposed that the reoccuring problems with the throttle mechanism might originate from too much movement between the throttle engine and proposed there may be an issue with the engine mounts (Part no to confirm but likely Figure 17 of parts list). Mixture setting was set at 1.75 turns back from endstop
2014-10-16 Dmitro Khroma Over summer I placed 3 washers into the tiller arm mechanism to remove the free play and enable the gears to mesh properly. Dry test appears to have fixed the problem. This is a temp solution. A full repair will need to be made once the correct tools are attained.
2014-05-07 Alex Bourla Issue in which tiller arm does not mesh correctly appears to have worsened making it increasingly difficult and occasionally impossible for engine to reach full throttle. Additionally, the the bolt/nut connecting the tiller arm to the throttle mechanism inside the engine kept coming off at sea, probably simply be a case of replacing this bolt/nut.
2014-04-14 Jon Spark plugs replaced, carburetor cleaned and sytem drained of fuel at PK
2014-01-07 Tim Walsh EU environmental legislation has prevented the sale of light powerful 2-stroke engines like Millie. There are modern 2-stroke engines like Evenrudes ETEC and Tohatsu TLDI engines and also 4 strokes. However all modern 40Hp engines have a mass of 1.5 times that of Millie. Consequently Millie must currently be assumed to be irreplacable
2013-08-26 Sascha Troscheit No problems with Millie except that the throttle cog can still disengage when the tiller handle is lifted but uncertain whether that is a design feature
2013-05-25 Tim Walsh Wet Bristol 92.64 Tiller throttle fixed
2013-05-07 Tim Walsh Universal Pinon gear in throttle mechanism is damaged.
2013-04-08 Tim Walsh 2900.00 Current new replacement cost=£2900
2013-03-19 Tim Walsh Carb Casket replaced by Gus
2013-03-19 Jon Hauser Top cylinder compression=125psi, lower cylinder compression=120psi
2013-02-23 Kieran.Wood Replaced pull cord
2013-01-09 Tim Walsh Wet Bristol 50.00 Corroded Main Carb Jet Replaced
2012-11-11 Andy Kiddier Millie Serviced by Andy, John, Alex, Hamish and Hazel