bmc engine wont start

[Captain Nitromors]

Hi my bmc engine wont start, i think it was due to running out of diesel, however i dipped my stick in tank and was about 4 inch up the stick, is this a level that is empty? Anyway i put 30 quids worth of deisel back in and still wont start is this due to air in the system now as i have no idea how to bleed it

[RLWP]

It will be less than four inches if you stand on one side of the boat. and, yes, it's pretty common not to take fuel from the bottom of the tank where the sludgy stuff lives. And yes, your engine needs bleeding

 

Which BMC have you got?

 

Richard

[Captain Nitromors]

1500 bmc was running belting with no problem then sunday morning just turns over now till battery goes flat

[RLWP]

Bleeding a BMC 1.5: http://www.nauticus.co.uk/bmc.pdf

 

Richard

[Captain Nitromors]

sounds easy but not sure were the componants are that it mentions as im pretty thick were engines are concerned

[RLWP]

OK. First, the bits you are looking for are the fuel filter for steps 2 and 3, plus the lift pump, which is on the left side of the engine

 

The lift pump has a lever on the bottom, and often a wire handle with a circular loop on the end. Pulling this loop, or lifting the lever, pumps fuel through the filter and injection pump

 

The fuel filter will be somewhere around the top of the engine, and will have several pipes running into it. It may also have a bleed screw, a bolt on the top offset towards the bracket (not the central bolt)

 

If you do steps 1, 2 and 3, it might start.

 

If not, the next bits are on the injection pump. This is the thing sticking out of the right hand side with loads of metal pipes. Examine it carefully and you'll find the two bleed screws in the diagram, so you can do step 5

 

The injectors are on top of the engine, four things each with a big pipe going into the side and a little pipe joining them together along the top. Step five is about slackening off the nut on the end of two of the big pipes to any two injectors

 

If you are not confident, if you can find someone to help you, point them to the document I found. It'll make it easier for them

 

Richard

Edited May 12, 2014 by RLWP

[Tony Brooks]

I would strongly advise that as inexperience you totally ignore the bleed screw on top of the turret on the injector pump. ON may pumps it is part of the idle stabilisation damper and far too often people mess up the adjustment when being ham fisted with the bleed screw there. The whole fitting is also glued into the pump and these get ripped out in a similar way. Just use the belled screw on the side and keep bleeding for at least 30 seconds AFTER you think that you have all the air out.

 

As Richard says the filter is usually mounted at the back of the cylinder head and offset to the right. Very often teh bleed screw is the banjo bolt that holds the injector leak off pipe or pipes to the filter head. When you loosen or tighten it make sure that you do not allow the pipes to twist or you will be buying new ones.

[RLWP]

Thanks for adding that Tony, you have far more experience of recalcitrant BMCs than I do

 

Richard

[b0atman]

1 are you getting white smoke out of exhaust on start attempt

2 if not check fuel stop is ok .

Then replace fuel filter before starting maybe full of sludge .

My old BMC1500 self primed with a squirt of easy start .

good luck that its simple.

[Traveller]

What happens if, as in the case of a local Broads type cruiser, the feed from the tank by-passes the lift pump? Is there another way to circulate the duel?

[Tony Brooks]

In that case they are relying on the transfer pump in the injector pump to pump the fuel OR the tank is higher than the engine. In the latter case the fuel should just flow through by gravity. However I am not sure you have fully investigated the fuel system. Are you sure that you have not been tracing the leak off pipe rather than the feed. The other option is that the engine is fitted with an electric fuel pump as per certain Vetus and Izusu. In that case simply turn the ignition on.

 

Even if it was gravity fed I do not see what is gained by bypassing the lift pump as its on the engine anyway.

[Traveller]

It is not my boat, Tony, but is certainly a BMC 1.5 where the fuel feed does seem to pass the lift pump! I reckon the tank is higher than the engine and to be honest the lift pump is not easy to get at. May be a convenience thing?

Thanks

Colin

Edited May 12, 2014 by Traveller

[FORTUNATA]

It is not my boat, Tony, but is certainly a BMC 1.5 where the fuel feed does seem to pass the lift pump! I reckon the tank is higher than the engine and to be honest the lift pump is not easy to get at. May be a convenience thing?

 

Thanks

Colin

I've had some experience with electric fuel injector pumps. As Tony stated they require no mechanical lift pump at all and are electrically energised. It seems clear your BMC does have a normal lift pump but just thought I'd chip in. You can hear an electrically energised injection pump click when switched on and only then will it function as normal.

Another point I'd make is a lot of the primer levers for lift pumps are enough to try the patience of a saint. Some take ages to draw fuel. I found a much easier system is to use a clean brass sump oil pump and apply the nozzle to the fuel filter till you see diesel bubble out. Takes literally 2 or 3 draws of the pump and presto.