Bleeding A volvo MD2020

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woody001

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Hi,

Iam changing the pre filter and fuel filter on my md2020, I havent yet tried bleeding this engine.
I ahve been on the rya diesel course, and think i'll be ok.
Do you guys have any hints/tips on bleeding this engine quickly?

cheers all

respect.

woody.
 
On my 2030, I always change the pre-filter first and then run the engine until the air from the new pre-filter gets into the system. That has the effect of sucking up the fuel into the new pre-filter that saves a bit of waggling on the lift pump. If you seem to be getting nowhere, turn the engine over in case the lift is sitting on the cam and not getting a full stroke. Slacking the bleed nipple on the fuel filter is normally sufficient on my 2030 and I find I don't have to slacken at the the injectors as spinning it on the starter briefly will get it going. Sometimes it takes longer than others but it always gets done.
 
When I bleed a diesel I always do it the same way.
1 Change all the filters.
2.Tighten the pre filter bleed screw.
3. Loosen both engine filter and injector pump bleed screws and open throttle 50%.
4. Using the ignition key - turn the engine over continuously until diesel appears at the engine filter bleed screw.
5. Tighten it. Engine still turning over!
6. When diesel appears at the injector pump bleed screw tighten it. Engine still turning over!
7. Engine should fire up!

The trick is to keep turning the engine don't stop until the engine fires or you're not getting diesel from the engine filter after (say) 10 secs. If that happens check for air leaks.

Peter.
 
Fill your diesel tank right up to the top of the fill up pipe.
Gravity will save a lot of pump waggling.
 
Why would you want to do it quickly? As far as I can see, the whole point of doing any type of maintenance on a boat is that it should be as painful, and take as long, as posible. Otherwise those clever people at Volvo would have put all the service points where you could get to them without excrutiatingly painful contortion!

Seriously though I did the same job on my 2020 a couple of weeks ago and, without any 'tricks', the bleeding took about 10 mins. The old thumb was a bit sore (top tip; wear a glove!) but in the whole scheme of things it didnt seem like an excessive amount of time / pain - and the engine fired up first time.

Mark
 
The bleed positions are all at the front of my Yanmar. The in-line fuel lilter is at the back of the engine but WTH, you can't win them all and even back there I can replace it from the front at a pinch so no removing the cockpit sole needed.
 
Beware - flooding risk!

I'd be very wary of turning the engine over for any length of time without first closing the inlet cooling seacock. Unless the engine's actually running, there's nothing to force the cooling water out of the exhaust, with the possibility of the exhaust filling with water and causing hydraulic lock which could wreck the engine.

It also seems a bit risky tightening bleed screws whilst the engine's turning over, but then this sailing game is risky, isn't it?
 
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If you seem to be getting nowhere, turn the engine over in case the lift is sitting on the cam and not getting a full stroke.

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This is a very good point. The most controlled way to turn the engine over is to use a spanner to turn the nut on the alternator belt drive pulley. Turn it a quarter of a turn at a time and check if fuel squirts out of the filter housing (only fit the filter when you can see that fuel is being pumped out). Next time I do it I plan to count how many strokes it takes to fill the filter.
 
Re: Beware - flooding risk!

[ QUOTE ]
It also seems a bit risky tightening bleed screws whilst the engine's turning over, but then this sailing game is risky, isn't it?


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Not risky at all - the only pressure there is that generated by the lift pump!

Peter.
 
Re: Beware - flooding risk!

[ QUOTE ]
And also the starter only has an advised 30 second run time !


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Steve as I said in my post if nothings happening within 10 secs - stop and have a look.

If however the system is air-tight then it should take less than 15 secs to bleed the engine out and start it.

If you feel safer by closing the sea cock then by all means do so.

One nice thing about the new Yanmar 3YM30 is that you only have a bleed screw on the engine filter now - the injector pump is self-priming.

Peter.
 
changing ya filters

Well seeing as no one has told you.... /forums/images/graemlins/confused.gif

On your 2020, same on 2030, 2010 etc etc you need to rotate engine, easy enough with spanner, socket etc so that the mark on the pulley is aligned with the 'top' marking. Or else the lift pump will do/lift [--word removed--] all.

On the lower pulley, on its inside face is a clear notch, if new enough probably find a splash of yellow paint highlighting said notch. This needs to be in line with 'top' marking on the adjacent cover. Roughly about 10 o’clock, if your thinking that way.

If pump action still poor, and bear in mind its not that good anyway, rotate engine a further turn so that notch lines up.

Start with bleed screw on engine fuel filter, which should be more than sufficient. Dont be of the belief you should expect to see squirts of fuel, it dont often happen like that ok. A dozen or more 'pumps' should be all you need.

If per chance thats not sufficient, which is unlikely, release the delivery pipe at the injectors a few turns. Set the throttle wide open, max rpm. Run engine on starter until fuel pisses out of delivery pipe, and then tighten delivery pipe nuts. Tighten torque 20-25 Nm, if you want to appear really flash!!!

You may need two pairs of hands, as no doubt you wont reach panel from engine, but its totally plausible to DIY on your own.
 
Think about doing all of this in anger at sea! Why not consider adding a diesel-rated rubber bulb pump into the fuel line, painting the bleed screws bright red or yellow and labelling the spanner size on the filter casing? Undo screws a few turns, couple of squeezes of bulb until clear fuel comes out, tighten screws and way you go.
 
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