Another bleeding BMC thread

[Berengaria]

Following my water coolant woes a few weeks ago, I've got another problem which I'm going to try and tackle...but I'm a bit stuck.

 

Last weekend I was running the engine whilst moored up (and keeping an eye on the temperature lol) when it suddenly cut out. No drama, just quietly cut out quite gracefully. My initial thought was I'm out of fuel, as I'd been running it pretty close to empty, even though I was planning a top up the very next day.

 

I'd read that engines can need bleeding in cases of fuel running out, so tonight, after putting 20 litres in (and still not being able to start the engine), I attempted to bleed the system using info found on various threads here. As I'm posting here I've obviously been unsuccessful, and as I don't want to completely flatten the battery, I need some help please.

 

I'll run through exactly what I did, and apologies beforehand as I don't know all the names of the engine parts yet - I'm learning this as I go along. I'd really appreciate anyone pointing out something I might have missed, or did incorrectly.

 

1) I'd read that it might be a good idea to change the fuel filter whilst I was doing this bleeding malarkey, so as I had a spare, I ensured the fuel stop switch was engaged and undid the bolt holding the fuel filter in. I added the new one and tightened it all back up.

 

2) Now on to the actual bleeding. I opened the fuel stop again. Then, on top of the fuel filter, there's a place where the fuel comes in (I believe) from a metal fuel pipe. There's a bolt at this point, so I loosened the bolt a few turns and started pumping the manual lift pump. After a while (I assume because the new fuel filter was being filled) I started getting fuel evenly dribbling from the bolt, so I tightened it up.

 

3) Next, I did the same thing with the injector bolt immediately next to the fuel filter. And then the next, and next, moving away from fuel filter all the way to the fourth and last one.

 

I assumed now that the system was free of air, and tried to start the engine again. Still the same. It turns over but just won't catch at all. So I checked that the fuel stop switch was working properly, moving back and forth and checking the engine end.

 

The engine turn over sounds fine enough (apart from the fact the battery is now beginning to suffer a bit). Have I missed anything vital?

 

Many thanks!

 

Jason

[David Schweizer]

Assuming that you have actually filled the filter and purged any air up to that point, you now need to crack a couple of injectors open and wind the engine until fuel, free of bubbles, emerge from them. the engine should now start if you follow the normal starting proceedure.

[Berengaria]

Assuming that you have actually filled the filter and purged any air up to that point, you now need to crack a couple of injectors open and wind the engine until fuel, free of bubbles, emerge from them. the engine should now start if you follow the normal starting proceedure.

 

Thanks for the reply David. Now I've got the laptop again I've been able to look online a bit easier, and realised I've completely missed the fuel injection pump part out of the process. Is this a vital step? I would have assumed (lol) that if the injectors were leaking fuel, that would mean the pump is also full?

 

I also don't know if this is important, but I've been bleeding fuel from the banjo connectors on top of the injectors, and not the big 1 inch-ish bolts on the fuel lines below them....

[RobinJ]

1) I'd read that it might be a good idea to change the fuel filter whilst I was doing this bleeding malarkey, so as I had a spare, I ensured the fuel stop switch was engaged and undid the bolt holding the fuel filter in. I added the new one and tightened it all back up.

 

2) Now on to the actual bleeding. I opened the fuel stop again. Then, on top of the fuel filter, there's a place where the fuel comes in (I believe) from a metal fuel pipe. There's a bolt at this point, so I loosened the bolt a few turns and started pumping the manual lift pump. After a while (I assume because the new fuel filter was being filled) I started getting fuel evenly dribbling from the bolt, so I tightened it up.

 

3) Next, I did the same thing with the injector bolt immediately next to the fuel filter. And then the next, and next, moving away from fuel filter all the way to the fourth and last one.

Firstly, you don't say which BMC, but I'll assume 1.5.

There was no real need to crack the 'plug' on the fuel filter, but right idea.

You don't say whether the injector pipe was the return pipe (on top) or the delivery pipe (on the side). Cracking the return pipes, does exactly the same as the plug on the filter, and you only need to do the one farthest away (No.4 counting from back).

 

On the 1.5, the injector pump is just below the filter and there are 3 bleed valves on the inlet, body and outlet, which if necessary need to be bled in turn. Finally the air need to be bled from each of the injector delivery pipes. All this has to be done while turning the engine over, so you'll need plenty of starter battery!

[Berengaria]

Firstly, you don't say which BMC, but I'll assume 1.5.

There was no real need to crack the 'plug' on the fuel filter, but right idea.

You don't say whether the injector pipe was the return pipe (on top) or the delivery pipe (on the side). Cracking the return pipes, does exactly the same as the plug on the filter, and you only need to do the one farthest away (No.4 counting from back).

 

On the 1.5, the injector pump is just below the filter and there are 3 bleed valves on the inlet, body and outlet, which if necessary need to be bled in turn. Finally the air need to be bled from each of the injector delivery pipes. All this has to be done while turning the engine over, so you'll need plenty of starter battery!

 

Thanks Robin, it's a 1.8 sorry.

 

And no, I didn't touch the delivery fuel lines at all, I did all four ones on top lol

Edited February 3, 2013 by Berengaria

[by'eck]

Even with supposedly self-bleeding injection pumps there comes a point where some much air has been pulled through, you need to crack open the feed pipe unions to the injectors. Ideally all of them to see a fine spray coming out of each alternately and with the throttle wide open and engine cranking. This after successfully bleeding further down the line of course.

 

Nip up each union and with throttle still wide open, crank engine and it will start.

[Berengaria]

Even with supposedly self-bleeding injection pumps there comes a point where some much air has been pulled through, you need to crack open the feed pipe unions to the injectors. Ideally all of them to see a fine spray coming out of each alternately and with the throttle wide open and engine cranking. This after successfully bleeding further down the line of course.

 

Nip up each union and with throttle still wide open, crank engine and it will start.

 

By 'union' I assume you mean the big bolts that connect the fuel line to the injectors?

 

Thanks

[RobinJ]

It's a 1.8 sorry.

And no, I didn't touch the delivery fuel lines at all, I did all four ones on top lol

Turning the engine over has probably sucked some air into the injector pump, the 1.8 is more sensitive than the 1.5 (I think it uses slightly more volume and possibly because its higher up?).

The bleed valves on the 1.8 are similar, but difficult to get at, the one in the middle at the side should get rid of most of it, but you will still have to crack the injector feed pipes too!

Also check that you have a good seal on the filter, if its wet after pumping the priming lever, it may suck some air when turning the engine over!

[RLWP]

I'll see if I can find my BMC 1.8 manual and copy the diagrams for the bleed points on the pump that Robin is talking about

 

Our 1.8 won't start unless you bleed the pump properly

 

Richard

[RLWP]

I have copied the process as well as the diagrams. Hope this helps:

 

 

Richard

[David Schweizer]

Thanks Robin, it's a 1.8 sorry.

 

And no, I didn't touch the delivery fuel lines at all, I did all four ones on top lol

I am glad I didn't tell you that the injection pump is self bleeding as I believe that only applies to the 1.5, which has a completely different pump to the one which Richard has posted.

 

However for the benefit of any 1.5 owners reading this, I can confirm that the injection pump on the 1.5 is self bleeding, or should i clarify that the one on our 1.5 definitely is. I once inadvrtantly forgot that i had turned the fuel tap off and started the engine, only for it to die a few minutes later. A passing boater adviswed me that the pump should be self priming, so I filled and bled the filter, cracked open two injectors and wound the engine, (this is where you need a well charged battery and a starter motor in top condition) After about two minutes, I was beginning to dispair when suddenly the engine started spewing fuel from the two cracked injrectors.

[by'eck]

By 'union' I assume you mean the big bolts that connect the fuel line to the injectors?

 

Thanks

 

Well nuts usually but yes. Undo and pull back each pipe slightly so you can see whats coming out.

Edited February 4, 2013 by by'eck

[alan_fincher]

I am glad I didn't tell you that the injection pump is self bleeding as I believe that only applies to the 1.5, which has a completely different pump to the one which Richard has posted.

Yes,

 

I think you would be very lucky indeed to get a 1.8 injector pump to self bleed.

[Tony Brooks]

I am glad I didn't tell you that the injection pump is self bleeding as I believe that only applies to the 1.5, which has a completely different pump to the one which Richard has posted.

 

However for the benefit of any 1.5 owners reading this, I can confirm that the injection pump on the 1.5 is self bleeding, or should i clarify that the one on our 1.5 definitely is. I once inadvrtantly forgot that i had turned the fuel tap off and started the engine, only for it to die a few minutes later. A passing boater adviswed me that the pump should be self priming, so I filled and bled the filter, cracked open two injectors and wound the engine, (this is where you need a well charged battery and a starter motor in top condition) After about two minutes, I was beginning to dispair when suddenly the engine started spewing fuel from the two cracked injrectors.

 

 

I do not know how many 1.8s are fitted with the mechanically governed pump that is illustrated because I have never seen one. All those I have seen use the hydraulic pump which looks exactly like the 1.5 one except some have a bleed screw on one injector pipe union. I would ignore that and use the union nuts on the injectors. The bleed screw for the pump is in a very similar position to that illustrated, its the top of the pump that is different.

[RLWP]

I do not know how many 1.8s are fitted with the mechanically governed pump that is illustrated because I have never seen one. All those I have seen use the hydraulic pump which looks exactly like the 1.5 one except some have a bleed screw on one injector pipe union. I would ignore that and use the union nuts on the injectors. The bleed screw for the pump is in a very similar position to that illustrated, its the top of the pump that is different.

 

That's because I'm an idiot and have scanned the pages for the BMC 2.2, not the 1.8

 

Whoops, thanks Tony

 

Richard

[Flocal]

You have dis-engaged the fuel stop switch

[Tony Brooks]

You have dis-engaged the fuel stop switch

 

 

Many marine 1.8s still use a manual stop but whichever it is you do have to make sure the stop is in the run position.

[Berengaria]

Many marine 1.8s still use a manual stop but whichever it is you do have to make sure the stop is in the run position.

 

 

Yeah the fuel stop is in the run position, the throttle open.

 

I just returned back from the boat - no luck unfortunately. I bled the fuel filter, also made sure that the fuel lead into the injector pump itself was free of air too.

 

Got to the injector pump, managed to locate and loosen one of bleed screws (near the top, 45 degree angle down the side), turned the engine over and saw fuel 'spitting' out in spurts, two or three times a second I'd say. Tightened it back up but had no luck loosening a nearby screw that was more upright on the top.

 

Opened up all four injector lines and turned the engine over again...by this time the battery was starting to suffer somewhat. Couldn't see any fuel at all coming out the injectors however, I was led to believe there should be a 'mist' or spray of fuel, but there was nothing at all. When I tightened them back up however my fingers did detect fuel around the connections, so I'm not sure whether this was evidence of fuel coming through the system, or some older residue.

 

I've had to bring the battery home to charge now, but it's not looking good. I'm out of ideas really.

 

EDIT - I do have to say thanks to Lisa Jarvis though, mooring enforcement officer. I've kept her in the loop and she's been highly hoopy about it all.

Edited February 4, 2013 by Berengaria

[Chris Pink]

 

 

 

I'm out of ideas really.

 

 

 

From my experience of the Devil's Brood (which some call a BMC engine) the vital thing is the grey smoke from the exhaust. Grey smoke - will start eventually. No grey smoke - will never start.

 

Try a blowtorch in the air intake. That'll sort it out - if 1. above.

[RLWP]

<snip>

Got to the injector pump, managed to locate and loosen one of bleed screws (near the top, 45 degree angle down the side), turned the engine over and saw fuel 'spitting' out in spurts, two or three times a second I'd say. Tightened it back up but had no luck loosening a nearby screw that was more upright on the top.

 

<snip>

 

This is the wrong way to do it. For the two bleed screws on the injector pump, you use the manual method, pumping the low pressure pump. You must do both

 

Richard

[Berengaria]

This is the wrong way to do it. For the two bleed screws on the injector pump, you use the manual method, pumping the low pressure pump. You must do both

 

Richard

 

Ah ok...the other one is an absolute bitch to get a socket to because of all the rigid fuel lines lol. Thanks Richard.

[RLWP]

I seem to remember using a small open ended spanner on that one

 

Richard

[Berengaria]

I seem to remember using a small open ended spanner on that one

 

Richard

 

Yeah I've got an 8mm socket I was trying to use. The adjustable spanner I have can physically go to 8mm but no way is gonna fit inside all that spaghetti.

[alan_fincher]

Got to the injector pump, managed to locate and loosen one of bleed screws (near the top, 45 degree angle down the side), turned the engine over and saw fuel 'spitting' out in spurts, two or three times a second I'd say. Tightened it back up but had no luck loosening a nearby screw that was more upright on the top.

Be very careful to only loosen the things on the injector pump that the manual says you must.

 

One of the thinks you can screw out actually has a small ball bearing that should be there to form a seal, but which can spring out and get lost.....

 

........ but please don't ask me how I know that....

 

 

Opened up all four injector lines and turned the engine over again...by this time the battery was starting to suffer somewhat. Couldn't see any fuel at all coming out the injectors however, I was led to believe there should be a 'mist' or spray of fuel, but there was nothing at all. When I tightened them back up however my fingers did detect fuel around the connections, so I'm not sure whether this was evidence of fuel coming through the system, or some older residue.

If you are just removing the high pressure feeds to the injectors, (or more correctly just loosening them at the nut at the injector end, the you will not get "mist". "Mist" is what comes out of the injectors themselves, and you'll not get to see that. If fuel is coming through a properly bled injection pump, then as the engine turns over, significant amounts will be spat out of the "cracked open" injectors. If you are not seeing enough to make a small mess, then I don't think you have adequately bled the injection pump.

[Berengaria]

Be very careful to only loosen the things on the injector pump that the manual says you must.

 

One of the thinks you can screw out actually has a small ball bearing that should be there to form a seal, but which can spring out and get lost.....

 

........ but please don't ask me how I know that....

 

 

 

If you are just removing the high pressure feeds to the injectors, (or more correctly just loosening them at the nut at the injector end, the you will not get "mist". "Mist" is what comes out of the injectors themselves, and you'll not get to see that. If fuel is coming through a properly bled injection pump, then as the engine turns over, significant amounts will be spat out of the "cracked open" injectors. If you are not seeing enough to make a small mess, then I don't think you have adequately bled the injection pump.

 

 

Thanks very much. Yeah I did read about your ball bearing issues elsewhere

 

I think you're right, the pump must not be bled right, but I'm darned if I know how I'm going to be able to loosen that other nut...it's practically impossible to get a grip on it because of the positioning.

 

I swear I'm never EVER running out of diesel again..