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1979 C&C 30 Mk I - 2QM15
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Discussion Starter #1
This looks simple enough, unscrew the bell, change out the filter, screw it back on. But I've already had a couple 5 minute jobs turn into 5 hour jobs, (e.g. the frozen zinc I'm still trying to remove...). So...

When I unscrew the bell that houses the filter, how much diesel fuel is likely to spill out? And what's the best way to contain it? (I don't want to reintroduce the diesel smell that took me a month to get rid of after the first got the boat).

Am I going to have to bleed the system after I do this, or will just cranking it work out any air in the system?
 

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I would put a couple of rags underneath, to catch the spills, and have a small ice cream container to pour the rest in. Will be 1/4 - 1/2 cup or so.

When you put are putting the new filter on, fill it up near the top, so you don't have to prime as long afterwards. It takes a while to fill the whole space using the manual pump.

There are lots of posts on priming, but if the manual pump doesn't feel like its doing anything, you usually can turn the crank by hand, 1/2 turn or 1 turn and then retry - as the pump only works with the crank / camshaft on a certain stroke.
 

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The other trick for bleeding air that I picked up here is to put an outboard style priming pump in the fuel line right where it comes out of the tank.

Then there is no messing around with the manual pump that I never seem to get to work. Just hook everything back up and open the vent on the first filter and pump till diesel comes out then move on to the second filter, works great.

Gary
 

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1979 C&C 30 Mk I - 2QM15
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Discussion Starter #4
Ok... I see a bleeder bolt at the top of the filter case. But I'm not seeing anything listed in the service manual diagrams that's described as a "manual pump". Where is this located?

After installing the filter, will just cranking the engine with the starter long enough pump out the air? Or will it remained trapped in the lines until I bleed them?
 

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Fuel pump on the engine has manual level, to pump fuel up manually. It is hard to get to on Yanmar 2QM15. Fuel pump located under fuel filter, the filter’s input fuel line starts at fuel pump, it is small round shaped thingy. There is a level under the pump. You need to pump it, make sure you bring it all way up on every stroke.
2QM15 require to bleed
1. Fuel filter(screw on top). There is disposable plastic washer under it, you need to replace it frequently
2. Fuel return lines on injectors, start with rear one. There are cooper crushing washers, need to be replaced when crashed
3. Fuel lines at injectors
 

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Gary - I have thought about putting an outboard squeeze bulb on, before the racor. However, my concern was that my current fuel lines, from tank to racor, and racor to manual fuel pump, have nice "professional" fittings terminating them. I did not wasnt to cut them off, to spice in an outboard type hose with hose clamps, for example. I was afraid of having air leaks.

How did you connect the squeeze bulb? Can you get them with "standard" fittings to connect to the existing fuel line?
 

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I also use the primer bulb for bleeding. They can be purchase with different size hose barbs.
I believe the little Yanmar filter is a five micron, I use a two micron in the Racor that way I figure I never have to mess with changing the Yanmar filter?
Bill,
 

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My engine mechanic used a motorized pump that he used to suck the oil out of the drip pan. He added a small metal tube insert on the hose end, and attached it to the return hose after the injectors, that also goes back into the top of the fuel filter housing instead of the tank on my 2QM15. When he applied the suction, the fuel was pulled from the tank, through the Racor filter, past the mechanical pump on the engine, into the fuel filter housing, into the injector line, and when some came into the waste oil bucket, he shut the pump down, and re-attached the return hose to the fuel filter housing. Thus priming the entire system. Worked really well. My engine started up on the first try. You could do the same thing with a hand pump as well.
 

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I just used the little SS hose clamps to install the primer bulb. Bill you should use a 10 or 20 micron pirmary filter before your Yanmar secondary filter. The Yanmar secondary filter should be replaced at least yearly. Even water can cause it to break down so.
With the priming bulb it is dead easy to replace both of them and then get the engine running.

Gary
 

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I disagree with a few things above. Do not pre-fill filters more than half way. You can end up with an air slug that gets forces into the high pressure side of the fuel system. If you do that you will have to bleed to air at the injectors as well. If you properly bleed the low pressure system you don't have to bleed the air from the high pressure side during a filter change.

The squeeze bulb isn't necessary at all. The manual lever on the lift pump actually pumps more than you would think based on feel. I don't pre-fill my filters at all and it really doesn't take that much pumping to fill the Racor primary and the engine mounted secondary filter.
 

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Steve - I am not doubting you. But what exactly is an air slug? And how would filling a filter =, say 3/4 full, leaving 1/4 volume to be forced/ bled out by incoming fuel be more of a problem that having it empty, and having to force out / bleed the whole volume.

Again. not being a smart$ass!! Just would like to learn - see if I am overlooking something. I haven't had a problem with filling them as much as possible b4 bleeding, but have only had to do it a couple of times.
 

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An Aussie Sailor
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Having suffered from a stoppage due to a fuel blockage,I reckon you cannot have too many filters.
My set up is a follows.
Tank to line with fuel bulb for priming to first canister filter "Ryco" brand, larger and cheaper to replace element the the genuine Yanmar article, connector line to Yanmar canister filter, line to engine mechanical pump then the small secondary filter.

The head of fuel in the tank pretty much will refill both the large canister filters but the primer bulb speeds it up.
The manual lever on the engine driven pump then primes up the low pressure side of the system. No problems re-starting, no airlocks on high pressure side.
I also regularly add a water absorbent additive to the fuel and a biocide.

Mychael
 

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Splashed
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1. Put a plastic bag around the filter before removing it using the right tool. That will capture all the diesel. Put the plastic bag under the "belt" of the filter tool, the grip will not be as firm, but should be adequate still.
2. Bleed the system, it takes 2 minutes.

If it is still running a little rough, loosen the bleed-screw first, and if that's not enough, loosen the nuts on the injectors one by one, while the engine is running bleeding that last air out that might have been captured. But be careful though, it can easily penetrate your skin.

Typically it's a 10 minutes job.

This looks simple enough, unscrew the bell, change out the filter, screw it back on. But I've already had a couple 5 minute jobs turn into 5 hour jobs, (e.g. the frozen zinc I'm still trying to remove...). So...

When I unscrew the bell that houses the filter, how much diesel fuel is likely to spill out? And what's the best way to contain it? (I don't want to reintroduce the diesel smell that took me a month to get rid of after the first got the boat).

Am I going to have to bleed the system after I do this, or will just cranking it work out any air in the system?
 

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Steve - I am not doubting you. But what exactly is an air slug? And how would filling a filter =, say 3/4 full, leaving 1/4 volume to be forced/ bled out by incoming fuel be more of a problem that having it empty, and having to force out / bleed the whole volume.

Again. not being a smart$ass!! Just would like to learn - see if I am overlooking something. I haven't had a problem with filling them as much as possible b4 bleeding, but have only had to do it a couple of times.
If you pre-fill the filters you can create an air slug by trapping some air at the top of the filter, then pumping the lift pump a bit which forces the air into the supply lines. You think you have clear fuel to the secondary so you stop priming and button every thing up. But in reality their is air in the lines behind the clear fuel. You start the motor, which runs fine for a few minutes until the air slug is forced into the high pressure side. Then the engine quits and now you have to bleed the low pressure side, then the high pressure side too. A mechanic explained this to me. I realized I had done this exact thing myself. You can get away with a little pre-filling at little fuel but I'm not really sure it's worth it.
 

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Disposable diapers soak up more liquid than anything else on earth. Put one beneath where it will catch any drips and you will be in good shape
 

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we went a added a small electric fuel pump between the Racor and the engine. Put a switch close by. Works super easy to prime when changing the racor or the engine filters. I just flip the switch and open the bleeder. Pump was around $20. Have the Yanmar 2GM
Thisisus
Islander 32
Mobile AL
 
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