Bukh diesel - difficult to start

[jhward]

Our Bukh 10hp saildrive has allways started without any throttle for the last 2 years. About 3 weeks ago it refused to start and we bled the system before we could commence our journey.
After examination of the filter and tank we found about 10ml of water in the 5 month old Bukh filter and "dirt" in the tank and filter. Tank has been cleaned, a new "CAV" in line filter installed and Bukh filter replaced, tank dosed with bug killer and system bled.
However the engine requires 3/4 throttle to start but appears to go ok and idle satisfactorily in the original starting position. Could we have a blockage in the system some where and how do we find and fix? Could it be another problem ie dirt in the injector or problem with the fuel pump?
Regards

John H

 

[DavidWilb]

If you do not solve it then try BUKH on 01202 668840. I have a 10HP [but not saildrive] and have always found BUKH to be extremely helpful and knowledgeable.

 

[truebrit]

Probably the rack in the injector pump sticking in the off position. Next you try to start the engine, leave the throttle in your normal tickover postion, but give the injector pump two or three sharp taps with light hammer or heavy spanner!! if it starts Ok its the rack sticking. Will most likely clear itself in time .

 

[snowleopard]

i don't know that engine at all but symptoms like that would make me think the glow plugs had stopped working. my yanmars don't have pre-heat and you need 3/4 throttle to start them, similarly when the plugs failed on my diesel car it needed throttle for starting.

 

[AngusMcDoon]

The Bukh DV10 does not have glowplugs.

 

[oldharry]

The Bukh workshop manual gives the following points to check related to dirt/water in the fuel and poor starting;

Fule pump gives to small yield: air/water in the system or fuel pump filter clogged

Pressure valve sticking - dirt or water in the pump

Pump piston or cylinder worn/damaged - water /dirt in the fuel

Main Fuel filter clogged.

I have also found problems if the fuel lines have any trace of a leak, particularly between the lift and injection pumps, this can cause starting problems due to fuel starvation. Also if the fuel lift pump or its daiphragm are leaking at all.

There are no glowplugs, as Bukh fitted a manifold heater as an optional extra. I have not yet needed to use mine!

 

[silverseal]

Silly question really - have you really got all the air out? If there is still a small amount of air in the injector pump, then it will need throttle to start.

 

[jerryat]

Hi!

Used to have a B10 years ago and had a similar problem. As far as I can remember we traced the problem to the tiny filter in the fuel lift pump. If you remove the top of the pump (carefully cos there's a small spring that might leap out at you!) you will see a small circular filter that can, very occasionally become partially blocked. Worth checking anyway!

By the way, the lift pump is a standard (I think Lucas) lorry type pump available at a fraction of the BUkh price should you need to replace it!

Hope this helps,

Cheers Jerry

 

[VicMallows]

Note you comment 'Three weeks ago' when it was very cold. Bukhs do indeed have option of either an electric heater in the inlet manifold; or a thermostart (works with a diesel feed, electrically ignited by a glow-plug). I don't have either and in winter, the alternatives are to pump hot air into the manifold, or use ether ('easystart'). Would have started OK today in the South!.

Vic

 

[jerryat]

Hi Vic,

Yes, you are correct about the inlet manifold glowplug (I retro-fiited one to my current 20hp Bukh) but I wasn't sure the 'ten' had the tapping on the manifold for this. Evidently it does, so that's certainly an option for our friend.

Have to say though, that even in winter, I don't use the glow plug and, in fact, have only done so twice in 16 years 'just in case' when the batteries were a bit low!

Disagree re using 'Easystart' though. This is a difinate killer of diesel engines particularly if used regularly. If you have to, there's another basic problem with the ehgine that needs sorting.

Cheers Jerry

 

[philip_stevens]

The heater in the manifold is fitted into an extra piece of manifold that comes with longer bolts. I fitted one into/onto my DV20.

 

[VicMallows]

Sorry Jerry, but I really do subscribe to the view that the 'EasyStart' thing is just an urban myth, probably coming about because if you need to use it other than in really cold conditions, the engine probably has poor compression. Must be careful though to just give it a 'sniff' as agree you can wreck a con-rod if you create too bigger 'explosion' in the cylinder.

Recently had 3 glow-pins down on my Mondeo Diesel ..... it was near impossible to start, and that was at 15degC! (it was also impossible to change them without buying 2 specific spanners!).

Vic