BMC 1.5 starting problems.

[pete.i]

Hi all.

 

I have had a starting problem for the first time since I bought Keb early 2010. I know BMCs can be pigs to start in the cold but I haven't had any problems. Anyway after that last cold snap we had I went down to start the boat, as I do every other day, and it wouldn't start. There was plenty of battery and the starter was spinning the engine over beautifully but it wasn't even trying to fire. There was no smoke coming from the exhaust which I have been told was indicative of no fuel getting to the injectors. I had plenty of fuel in the tank so it wasn't that. I took one of the connectors off from an injector and all I was getting was a dribble of fuel from the pipe. At that point I decided to call it a day.

 

I went back down to the boat today to bleed the fuel system to, hopefully, sort things out. Bleeding the fuel system did indeed get it going again. I tightened some of the fuel pipe unions up which were weeping diesel and everything seems to be okay now.

 

I do have a couple of questions though. When bleeding a diesel engine, specifically a BMC 1.5, I would have expected the power of spurting fuel from loosened pipe unions etc to be a lot more powerful than what I appeared to be getting. I started at the lift pump and loosened the coupling to the filter. Fuel pumped out from that ok when I operated the lift pump. I worked back to the injector pump and the power of the pumping fuel seemed to be weak at the input to the injector pump but it was pumping. I loosened off the first bleed screw on the injector pump and nothing came out. I loosened it further and still nothing came out. I then took the screw right out and each time I operated the pump a small quantity of fuel dribbled out. As the level of fuel was right up to the lip of the screw hole I replaced that screw and went to the one on the top of the pump. Again I had to remove this screw completely to see any fuel coming out. To be fair the guy on You Tube, who shows you the bleed sequence for a BMC 1.5, says that you don't get much fuel out from this bleed point. The next points I did were the injector unions. I loosened all the union nuts and turned the engine over with the stop lever fully forward and the throttle fully open as per the instructions. I got fuel dribbling down the four pipes so I tightened two up. and turned the engine over again till fuel dribbled down the two remaining pipes. I tightened up those two nuts and then started the engine after heating the heaters and it started and ran fine.

 

So should I expect more power to the force of the fuel from the various bleeding points or is what I was getting okay. It obviously worked but is it possible for the lift pump (or even the injector pump) to be not as good at pumping as it should be I am fairly certain (one for you here Leo) it is the original lift pump, as is the injector pump, so they would both be 30 odd years old I would think.

 

I don't really know why the engine didn't start. I'm assuming that some air had got into the system from the slightly loose pipe unions or that the cold snap caused the fuel to wax and that blocked the system temporarily.

 

Cheers

 

Pete

[bizzard]

Hi all.

 

I have had a starting problem for the first time since I bought Keb early 2010. I know BMCs can be pigs to start in the cold but I haven't had any problems. Anyway after that last cold snap we had I went down to start the boat, as I do every other day, and it wouldn't start. There was plenty of battery and the starter was spinning the engine over beautifully but it wasn't even trying to fire. There was no smoke coming from the exhaust which I have been told was indicative of no fuel getting to the injectors. I had plenty of fuel in the tank so it wasn't that. I took one of the connectors off from an injector and all I was getting was a dribble of fuel from the pipe. At that point I decided to call it a day.

 

I went back down to the boat today to bleed the fuel system to, hopefully, sort things out. Bleeding the fuel system did indeed get it going again. I tightened some of the fuel pipe unions up which were weeping diesel and everything seems to be okay now.

 

I do have a couple of questions though. When bleeding a diesel engine, specifically a BMC 1.5, I would have expected the power of spurting fuel from loosened pipe unions etc to be a lot more powerful than what I appeared to be getting. I started at the lift pump and loosened the coupling to the filter. Fuel pumped out from that ok when I operated the lift pump. I worked back to the injector pump and the power of the pumping fuel seemed to be weak at the input to the injector pump but it was pumping. I loosened off the first bleed screw on the injector pump and nothing came out. I loosened it further and still nothing came out. I then took the screw right out and each time I operated the pump a small quantity of fuel dribbled out. As the level of fuel was right up to the lip of the screw hole I replaced that screw and went to the one on the top of the pump. Again I had to remove this screw completely to see any fuel coming out. To be fair the guy on You Tube, who shows you the bleed sequence for a BMC 1.5, says that you don't get much fuel out from this bleed point. The next points I did were the injector unions. I loosened all the union nuts and turned the engine over with the stop lever fully forward and the throttle fully open as per the instructions. I got fuel dribbling down the four pipes so I tightened two up. and turned the engine over again till fuel dribbled down the two remaining pipes. I tightened up those two nuts and then started the engine after heating the heaters and it started and ran fine.

 

So should I expect more power to the force of the fuel from the various bleeding points or is what I was getting okay. It obviously worked but is it possible for the lift pump (or even the injector pump) to be not as good at pumping as it should be I am fairly certain (one for you here Leo) it is the original lift pump, as is the injector pump, so they would both be 30 odd years old I would think.

 

I don't really know why the engine didn't start. I'm assuming that some air had got into the system from the slightly loose pipe unions or that the cold snap caused the fuel to wax and that blocked the system temporarily.

 

Cheers

 

Pete

 

Your lift pumps internal operating lever was probably partially up on the camshafts cam instead of the cams back preventing full strong strokes on the external hand lever therefore lessening its pumping force and delivery.

[pete.i]

Thanks for that Bizzard. That is a possibility although the guy on You Tube did mention that possibility so I was aware that that could happen. I did turn the engine to where I thought the lift pump would be off the cam and at one point when I was trying to see the fuel coming out from the first bleed screw on the injector pump I turned the engine over on the ignition.

 

Cheers

 

Pete

[LEO]

Hi all.

So should I expect more power to the force of the fuel from the various bleeding points or is what I was getting okay. It obviously worked but is it possible for the lift pump (or even the injector pump) to be not as good at pumping as it should be I am fairly certain (one for you here Leo) it is the original lift pump, as is the injector pump, so they would both be 30 odd years old I would think.

 

I don't really know why the engine didn't start. I'm assuming that some air had got into the system from the slightly loose pipe unions or that the cold snap caused the fuel to wax and that blocked the system temporarily.

 

Cheers

 

Pete

 

Hi Pete,

 

I would think that the lift and injector pumps are original - the engine was marinised by J.G Meakes in the early 80's.

 

When I had to bleed the engine, I found it difficult and did not use the lift pump but turned the engine over on the starter, having 'cracked' nuts on the injectors.

 

It sounds to me as if you have a problem with fuel contamination, not sure if you have pumped out the bottom of the fuel tanks, as if not, it is quite possible that these have not been cleaned since the boat was new. About 18 months ago I ran the 50 gallon tank which supplies fuel to the diesel heater on Keb's replacement boat to virtually empty. This left about 1.25 inches of diesel/crud at the bottom of the tank.

 

I pumped this out and the crud which came out was amazing. You have 2 fuel tanks connected by a balancing pipe, one tank can be easily pumped out through the fuel inlet, the other by removing the fuel vent. You should make up a pump by using 15mm copper pipe (or less dia. for one tank) and incorporate an electric drill pump and run this until clean looking fuel comes out.

 

Then change the main fuel filter.

 

This may help the situation, unless a water trap has been fitted you will not be able to check for fuel contaminates.

 

You may also have problems with the dreaded 'fuel bug' and how old is your diesel? - you could be having difficulties caused by the new low sulphur fuel.

 

I used to treat the fuel with 'Fortron' when I had the boat.

 

Hope this helps, these BMC 1.5 are great engines and really should be up there with the classic vintage engines, looked after they will run for ever.

 

Mike.

Edited March 21, 2013 by LEO

[trackman]

On the 1.8 I used to help care for the pressure from the lift pump varied, from a gentle bubble to a reasonable spurt according to circumstance, much as Blizzard described.

 

The real pressure only comes from the injector pump, obviously, and you don't went to mess with that, it can penetrate the skin with nasty results.

 

I always bled the injectors by cracking the union on each, one at a time, until no froth emerged.

 

I would recommend Marine 16 as the fuel additive to stop diesel bug. Search on here for the discussions that point to that conclusion. However, it does not emulsify any water so that it gets passed through the engine as some additives claim. This is probably a good thing but does mean you really must get any water out of the tank by other means, as already described.

Edited March 21, 2013 by trackman

[pete.i]

Thanks for the replies.

The diesel was topped up last week it took 47 litres. Of course, because I don't run the tank to empty, old diesel will still be in there. I do use an additive which, I think, is Marine 16. It could be crud but I don't think it's diesel bug or the new (crappy european forced on us) diesel because I have been using that diesel for a while now without any problems.

 

I have been told that the diaphram in the lift pump can deteriorate and/or develop pinholes over the years and not pump as well as it did when new. The reason why I'm hedging that way is that the power of the flow did not seem to be sufficient at the bleed points before the injector pump. Thanks for the heads up about the pressure from the injector pump Trackman. Whilst I am appreciative of the warning I was aware of that and in fact said that the first thing I did was take one of the injector feed pipes off and all I got was a dribble from the it when I turned th engine over. I had expected a huge, extremely powerful, stream of diesel from there and I didn't get that. At that point my first thought was the injector pump. But having said that there was no way in the world that the pressure from the lift pump was sufficient to push diesel past the first bleed screw on the injector pump. I had to remove the screw to see any flow at all. So I think I am going to replace the lift pump, as these are not too expensive, and see how it goes. As I have said after bleeding the system the engine did start and ran fine for a hour and a half but I still don't know why it stopped in the first place other than the fact that there was no fuel getting to the injectors.

 

Whilst I am on the subject does anyone know if there are service kits for the various lift pumps fitted to these engines. I will also clean out the diesel tanks as per your suggestion Leo, although, I am not going to do that just yet. It's okay for you lot dahn souff living in sub tropical temperatures us Yorkies (and no I didn't write that thread about a business) are b****y freezin up here, which could also have stopped my engine running.

 

Cheers

 

Pete

[bizzard]

Thanks for the replies.

The diesel was topped up last week it took 47 litres. Of course, because I don't run the tank to empty, old diesel will still be in there. I do use an additive which, I think, is Marine 16. It could be crud but I don't think it's diesel bug or the new (crappy european forced on us) diesel because I have been using that diesel for a while now without any problems.

 

I have been told that the diaphram in the lift pump can deteriorate and/or develop pinholes over the years and not pump as well as it did when new. The reason why I'm hedging that way is that the power of the flow did not seem to be sufficient at the bleed points before the injector pump. Thanks for the heads up about the pressure from the injector pump Trackman. Whilst I am appreciative of the warning I was aware of that and in fact said that the first thing I did was take one of the injector feed pipes off and all I got was a dribble from the it when I turned th engine over. I had expected a huge, extremely powerful, stream of diesel from there and I didn't get that. At that point my first thought was the injector pump. But having said that there was no way in the world that the pressure from the lift pump was sufficient to push diesel past the first bleed screw on the injector pump. I had to remove the screw to see any flow at all. So I think I am going to replace the lift pump, as these are not too expensive, and see how it goes. As I have said after bleeding the system the engine did start and ran fine for a hour and a half but I still don't know why it stopped in the first place other than the fact that there was no fuel getting to the injectors.

 

Whilst I am on the subject does anyone know if there are service kits for the various lift pumps fitted to these engines. I will also clean out the diesel tanks as per your suggestion Leo, although, I am not going to do that just yet. It's okay for you lot dahn souff living in sub tropical temperatures us Yorkies (and no I didn't write that thread about a business) are b****y freezin up here, which could also have stopped my engine running.

 

Cheers

 

Pete

If you set the lift pumps lever on the cams back and remove the outlet delivery pipe from the lift pump holding a thumb over the pipes end to prevent air from entering and pump the hand lever with the other hand quite a strong gushing flow of fuel should spurt from the pumps outlet port. You will probably have to do a little bleeding after this test.

Only a small pulse of fuel is ejected from each injector pipe at every second revolution of the crankshaft but under very high pressure nevertheless.

Lift pump overhaul diaphram kits were commonly available for all petrol and diesel lift pumps at one time. I've overhauled numerous pumps in the past using the kits, but rare to find these days. AC being the most common make of lift pump. Try ASAP.

 

There are also pattern lift pumps around as AC replacements usually perfectly good if not better. Moprod springs to mind.

Edited March 21, 2013 by bizzard

[pete.i]

If you set the lift pumps lever on the cams back and remove the outlet delivery pipe from the lift pump holding a thumb over the pipes end to prevent air from entering and pump the hand lever with the other hand quite a strong gushing flow of fuel should spurt from the pumps outlet port. You will probably have to do a little bleeding after this test.

Only a small pulse of fuel is ejected from each injector pipe at every second revolution of the crankshaft but under very high pressure nevertheless.

Lift pump overhaul diaphram kits were commonly available for all petrol and diesel lift pumps at one time. I've overhauled numerous pumps in the past using the kits, but rare to find these days. AC being the most common make of lift pump. Try ASAP.

 

There are also pattern lift pumps around as AC replacements usually perfectly good if not better. Moprod springs to mind.

 

Thanks for that Bizzard. I will try the pump test when I go to the boat tomorrow. I can get a new pump off EBay for around £20 ish plus postage so they aren't expensive. I was just thinking of overhauling the old one so that I had a spare although the one I have has lasted 30 odd years so I doubt I would ever need a spare.

 

Pete

[ditchcrawler]

Thanks for that Bizzard. I will try the pump test when I go to the boat tomorrow. I can get a new pump off EBay for around £20 ish plus postage so they aren't expensive. I was just thinking of overhauling the old one so that I had a spare although the one I have has lasted 30 odd years so I doubt I would ever need a spare.

 

Pete

A fine selection at ASAP and £20 for a BMC 1.5 http://www.asap-supplies.com/search/Diesel+lift+pump

[pete.i]

A fine selection at ASAP and £20 for a BMC 1.5 http://www.asap-supplies.com/search/Diesel+lift+pump

 

Cheers Ditchcrawler that lokks the same as mine I will order that.

 

Pete

 

lokks???? I meant looks.

Edited March 21, 2013 by pete.i