Bukh DV20 Engine
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This page gives information which may be useful to any Bukh DV20 owner. The spares are entered in relation to when they were purchased so the cost may not reflect todays prices. The ~ indicates approximate cost. For list of distributors world wide visit the Bukh web site at www.bukh.dk 

The engine mechanical information is something I can never lay my hands on so, being here I can always lay my eyes on it.

Engine anode
Valve Adjustments
Flywheel Bolt Torque
Fuel Pump Filter Cleaning 
Volvo Prop Shaft Seal (Every Launch)


Oil filter same as used for Ford Escort:
Ford AP1011
Halfords HOF200
Champion C104
Fram PH966B

Fuel: primary fuel filter:

The original filter replaced with CAV oil filter/water separator. When fitting the filter housing ensure that the fittings are compatible with the thread of the housing and input/output pipework. The cost of the housing complete with filter ~50.00 sterling. The glass bowl should be inspected at regular intervals for signs of fuel contaminants and the filter should be changed annually. 
Filter element: Lucas 7111 296

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Fuel: Engine fuel filter

The engine fuel filter is mounted at the rear of the bukh engine. A drain plug is situated on the bottom of the filter and a bleed screw is positioned on the filter housing, marked here in yellow. Drain a small amount of fuel into a clean receptacle if there is any doubt about fuel contamination. The filter requires changing infrequently if a good primary filter is used or at five year intervals if no fuel problems have occurred. Pt Number Bukh 610 D 0201 18.22

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Engine anode

The engine has a pencil anode fitted in a plug which is situated on the rear of the engine. This is to be replaced at least annually - cost ~7.00

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Item Manufacturer Part number Supplier ~ Cost
Starter Paris-Rhone 612A1650 Bukh (UK) 800 or recon 400
  Bosh 612A1600 Bukh (UK) 800 or recon 400
  Valeo D9E 51 12V Partco 205 Part exch
Alternator Paris-Rhone A13N 1M 14V 50A Bukh (UK)  
'V' Drive Belt   10 x 1100 APAS Engineering. 8.81
Alternator Regulator Paris-Rhone YL135 15 84 Bukh (UK)  
Oil Pressure s/w
0.8kg/cm2 (11-12psi) 1/8" BSPT
    Les Smith ~3.85
Water Pump Johnson Pumps 10-35157-3 Aquafax ~54.00
Water Pump Service Kit Johnson Pumps F35B-8 Aquafax ~12.00 ex VAT
Water Pump 'O' Ring   32.1x1.6mm Aquafax 1.44 ex VAT
Water Pump Lip Seal   05-29-139 x 2 Aquafax 5.26 inc VAT
Engine Fuel Filter Bukh 610 D 0201 APAS Engineering 18.22

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Valve Adjustments

Inlet Valve: 0.25mm 0.01inch
Outlet Valve: 0.30mm 0.012inch

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Flywheel Bolt Torque

On refitting of flywheel, the 'unbraco' bolts should be clean and dry. The threads must have Loctite applied before assembly. Tighten the bolts to a torque of:
8 - 8.5 kgm
58 - 61.5 ft/lbf

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Fuel Pump Filter Cleaning (S.E. Marchal 70BA)

Symptom: Engine hunts or splutters eventually stopping and then maybe starting again for a short period. Pump is situated at right hand side of engine. The pump includes a fuel filter which may require cleaning. To do this carefully unscrew the screws attaching the pump cover. CAREFUL! The spring may jump up.

The filter may now be cleaned and replaced.

Re-assemble in reverse order ensuring that the spring is fitted correctly. (See workshop manual).

Bukh Fuel Pump Filter

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Volvo Prop Shaft Seal (Every Launch)

When the boat is taken out of the water, the water runs out of the stern tube. At the next launch there will be air in the tube which will prevent water from reaching the rubber 'Volvo' seal (Part number: 828254 for 25mm shaft). Bukh Volvo Seal
Vent seal as follows:

The prop shaft seal, which is water cooled, must be vented after launching by compressing it at the lip seal at the same time as it is pressed toward the prop shaft. When water forces its way out of the gap the seal is vented.

Volvo Seal Greasing

Press approximately 1cubic cm of waterproof grease into the lips of the seal at every launch and every 200 hours of operation or annually.

This page was last updated on Tuesday, September 18, 2018 11:17 by Richard Spencer.