Genset bleeding

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dhays

Guru
Joined
May 26, 2015
Messages
9,567
Location
Gig Harbor, WA
Vessel Name
Kinship
Vessel Make
2010 North Pacific 43
I changed the fuel filter for my NL gender. I am trying to bleed the line and regardless of how long I pump the manual primer I am not getting fuel for M the bleed screw. I put diesel in the filter by t it wasn't filled completely. Ideas?
 
I changed the fuel filter for my NL gender. I am trying to bleed the line and regardless of how long I pump the manual primer I am not getting fuel for M the bleed screw. I put diesel in the filter by t it wasn't filled completely. Ideas?

some time the came to your feed but are at wrong position just crank 1 second you engine and you manual prime pump can work.:thumb:

Or some time to change you filter you close the fuel valve and you forgot to open :angel:

Hugues
 
I changed the fuel filter for my NL gender. I am trying to bleed the line and regardless of how long I pump the manual primer I am not getting fuel for M the bleed screw. I put diesel in the filter by t it wasn't filled completely. Ideas?

Does your pump req twist to open / enable pumping? Mine needs open before pumping and twist to close when done...
Just thinking "out loud"???
 
Tug's probly right, lift pump is on the high side of the cam and not letting your manual pump handle move the diaphram. I dislike manual lift pumps for numerous reasons, this being on of them.
 
Untighten the fuel line at the injector and prime until fuel comes out. Might try spray WD 40 in the carburetor and crank the engine. Do not use starter fluid.
 
How hard are you pressing on the pump lever? Sometimes it takes some effort.
 
I'm just guessin, but probly no carb. WD40 works if it has glow plugs. Not to safe if it has an intake heater or atomizer. As a last resort, pull the overflow plug on the filter housing and use a small funnel to fill it.
 
Thanks for all the help. I eventually got it to run.

FWIW, this is what happened. The Genset is a Northern Lights M373L3.3. Here is a picture from the manual. There is a little lever labelled "B" that is the manual priming pump. The bleed screw that I opened was "A". I have also attached a photo of my genset. You can see the little lever near the bottom of the photo. The lever is like a trigger that you pull back towards you. Very little resistance.

I must have been twiddling that lever for a good hour before I posted my question and I never got any fuel out of the bleed screw. I has backed it up enough that I could see the slot in the screw side that allows air and fuel to escape. Eventually, I gave up and tried to start the Genset. I caught but would quit. I then went back and this time took the bleed screw all the way out and again pumped away at that lever. This time, I could hear some action (maybe because the screw was out all the way I could hear it?). Looking down into the well where the screw would be, eventually I started to see some fuel rise. I replaced the bleed screw and pumped a few more times until I got diesel out of the hole. The engine then started up without having to open the second bleed screw at "C".

My guess is that Tug and kulas are right. The cam was just in the wrong position. My trying to start the engine simply put the cam in a different position so the pump worked.

You will notice the funny plastic thing around the filter in that photo. I cut the bottom off of an empty and dry water bottle. The filter wrench fit above it. When I loosened the filter, most of the fuel that spill out ran down the side of the filter an into that bottle. What little didn't was caught with a oil absorbent rag underneath. The first time I do something like this it takes me forever, mostly because I'm an idiot, but also because I spend a fair amount of time figuring out how to do it with the least mess. That bottle bottom not gets wiped out and is put in the same Rubbermaid container with all the other items for doing this job. I have to redo my container for this boat as it is all set for my sailboat.

So the next question is what about the primary fuel filter for the genset? It has a spin on Racor filter that I've never used before. It looks like the bottom of the assembly spins onto the filter and then the filter spins onto the mounting above it. Not sure how to take it off and apart without creating a large mess. Then once I get it back together, how do I go about priming that filter? I suppose I should get some diesel and fill the filter with it, but dang I hate to keep bottles of diesel fuel around for that. There is no priming pump installed other than the little manual priming pump mentioned above.
 

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David,needing to bleed my reman Onan after a filter change, there was a screw I worked out had to be the bleed screw, it was the only one with chipped paint. Opened it, pressed start, after a few seconds fuel appeared, the engine started, and ran, and I closed the screw. Perhaps that`s not the copybook method, probably 100 reasons why you shouldn`t which I`m just about to learn, but....
 
Untighten the fuel line at the injector and prime until fuel comes out. Might try spray WD 40 in the carburetor and crank the engine. Do not use starter fluid.

WD 40 also works on the 2 stroke 671 and perkins 435 which are compression. :flowers: however I do agree try the recommended way first.
 
David,needing to bleed my reman Onan after a filter change, there was a screw I worked out had to be the bleed screw, it was the only one with chipped paint. Opened it, pressed start, after a few seconds fuel appeared, the engine started, and ran, and I closed the screw. Perhaps that`s not the copybook method, probably 100 reasons why you shouldn`t which I`m just about to learn, but....

With a strong start battery (or jumper cables just in case) this is a perfectly good method to bleed diesel engines and certainly easier than messing with the fiddly manual pumps.

One needs to be careful and shut-down as soon as the engine starts to keep fuel from squirting around too much.
 
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Greetings,
Mr. dh. Congrat's on a successful (eventually) filter change. Sorry, but I must take exception to your comment "...it takes me forever, mostly because I'm an idiot,". WRONG!!! Your lack of experience does NOT make you an idiot.

Owning a different vessel which you are unfamiliar with is a learning experience. You now know about the cam location situation, how to keep things neat in THIS particular circumstance and you didn't break anything. All pluses IMO.
 
So the next question is what about the primary fuel filter for the genset? It has a spin on Racor filter that I've never used before. It looks like the bottom of the assembly spins onto the filter and then the filter spins onto the mounting above it. Not sure how to take it off and apart without creating a large mess. Then once I get it back together, how do I go about priming that filter? I suppose I should get some diesel and fill the filter with it, but dang I hate to keep bottles of diesel fuel around for that. There is no priming pump installed other than the little manual priming pump mentioned above.

2 solution

you can drain the fuel by drain plug and take you the bottom part of the filter (spins on bowl) need 2 belt-key or oil filter tool remover and after take out the filter from here clean the bowl instal new seal included on filter drew the filter on it fill with clean diesel (not the one you found on filter) and put all back together

or you can take out bowl and filter in same time and doing all mess on dock.

if you fill week diesel don't need to prim

look well some model have scroll wheel on top of silted hand screw and lift that a hand pomp after you use it screw back

have good mess

Hugues:thumb:
 
Call a trusted mechanic who does this for a living and watch what he does. Or rip out the NL genset and install a self priming Westerbeke!
 
2 solution

you can drain the fuel by drain plug and take you the bottom part of the filter (spins on bowl) need 2 belt-key or oil filter tool remover and after take out the filter from here clean the bowl instal new seal included on filter drew the filter on it fill with clean diesel (not the one you found on filter) and put all back together

or you can take out bowl and filter in same time and doing all mess on dock.

if you fill week diesel don't need to prim

Thanks Tug. Never thought about just using the water drain at the bottom to drain the filter before removing it. :facepalm:

This is the first spin-on that I've had that had a water drain. Makes perfect sense.
 
So the next question is what about the primary fuel filter for the genset? It has a spin on Racor filter that I've never used before. It looks like the bottom of the assembly spins onto the filter and then the filter spins onto the mounting above it. Not sure how to take it off and apart without creating a large mess. Then once I get it back together, how do I go about priming that filter? I suppose I should get some diesel and fill the filter with it, but dang I hate to keep bottles of diesel fuel around for that. There is no priming pump installed other than the little manual priming pump mentioned above.

Dave

I'm assuming you have A Racor 120A or similar on the Genset ...

and a Racor 500T or 900T on the main(s)...

On mine w/ these what I did was replace the drain plug on the Main 500T w/ a fuel rated petcock, hose barb, short hose & plug (for safety in case petcock gets bumped)

I use the 500T petcock & hose (vs the original plug) to drain any water - much neater... and this allows an easy way to fill the gennie R 120A canister assembly nearly full before replacing it - eliminates the need to carry carry diesel for filling and makes water drain neat & easy as well.

My Racor 500T is mounted low enough to allow gravity fill using bleed at top w/o need to prefill... so far all primary & secondary filter changes have restarted w/o much problem
 

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The Genset has a primary that is a Racor with a spin on cartridge. Not sure of the size but it is likely a 220 with a metal rather than plastic bottom. It has a drain plug at the bottom. I will have to look to see if it has any type of a bleed screw on the top. I think the fuel level in the tank is higher than the top of the filter, so it may gravity fill as long as my fuel level in the tank is high enough.

I have twin Racor 900s for the primary filters on the engine. I like your idea of using the drain on the bottom of those to supply fuel for filling the genset filter. I think they are a lower than the fuel level in the tanks as well. If I open the fuel supply line with the T handle cracked a bit, will those filters fill with gravity?

One silly question for y'all. When you drain a little fuel out of the bottom of your primary fuel filter to check for water or debris, what do you do with that nasty bit of diesel that is now sitting in your cup or bottle?



Dave

I'm assuming you have A Racor 120A or similar on the Genset ...

and a Racor 500T or 900T on the main(s)...

On mine w/ these what I did was replace the drain plug on the Main 500T w/ a fuel rated petcock, hose barb, short hose & plug (for safety in case petcock gets bumped)

I use the 500T petcock & hose (vs the original plug) to drain any water - much neater... and this allows an easy way to fill the gennie R 120A canister assembly nearly full before replacing it - eliminates the need to carry carry diesel for filling and makes water drain neat & easy as well.

My Racor 500T is mounted low enough to allow gravity fill using bleed at top w/o need to prefill... so far all primary & secondary filter changes have restarted w/o much problem
 
Well, apparently some folks put it in there genset filter, :) Bad idea, as any fuel that is drained (clean or not) has not been filtered.
 
Well, apparently some folks put it in there genset filter, :) Bad idea, as any fuel that is drained (clean or not) has not been filtered.

I never would want to try it with my Cummins QSB engine, but the Northern Lights/Lugger manual says to prefill the on engine filter with diesel fuel. That fuel has not been filtered. But then, the on engine filter is pretty small and if the cam is oriented the right way, it wouldn't take too long to prime manually.
 
As an aside to this (hijack?) I just helped my BIL change oil and filters in his NEW motorhome. It has a 6.7 liter Cummins electronic diesel engine. The engine manual stated "fill the fuel filter with clean diesel OR OIL". So, my suggestion, on numerous occasions, to fill the fuel filter with new ATF seems plausible. Even if you've never heard of anyone doing that. The main thing is that it is CLEAN.
 
As an aside to this (hijack?) I just helped my BIL change oil and filters in his NEW motorhome. It has a 6.7 liter Cummins electronic diesel engine. The engine manual stated "fill the fuel filter with clean diesel OR OIL". So, my suggestion, on numerous occasions, to fill the fuel filter with new ATF seems plausible. Even if you've never heard of anyone doing that. The main thing is that it is CLEAN.

yeah.... likely it would work out just fine but it would make me nervous. On my Cummins, supposedly it is self priming. The procedure is to key on the engine for 30 seconds, and then off. Repeat this 5 times and the new filter should be filled and bled. I will know once I actually try it out.
 
The Genset has a primary that is a Racor with a spin on cartridge. Not sure of the size but it is likely a 220 with a metal rather than plastic bottom. It has a drain plug at the bottom. I will have to look to see if it has any type of a bleed screw on the top. I think the fuel level in the tank is higher than the top of the filter, so it may gravity fill as long as my fuel level in the tank is high enough.

I think they are a lower than the fuel level in the tanks as well. If I open the fuel supply line with the T handle cracked a bit, will those filters fill with gravity?

One silly question for y'all. When you drain a little fuel out of the bottom of your primary fuel filter to check for water or debris, what do you do with that nasty bit of diesel that is now sitting in your cup or bottle?

Dave
I believe most of these types have bleeder - look for a plug w/ a screw driver slot & o-ring (Pic)
Also if it's a 220 I believe these have a priming pump built in -
see the 220/225 diagram or the 250 photo (note bleeder is removed) which I believe is similar to the 220/225

mine doesn't but mine gravity fills reasonably well same w/ the 500T / 900T as you mentioned - I loosen T - crack the inlet valve & fill via gravity... pretty easy & neat once you get the routine figured out for your situation

I usually use the drained diesel to start a campfire at our marina / park - alternate is to take home & add to the waste oil container I give to my local garage for winter heating

As others have mentioned just be cautious w/ self priming when cranking - keep it short or close cooling water inlet while purging / cranking.
 

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Dhays, look in your engine service manual and let me know what it says about filling the primary (first in the line the tank) just for my info, as I dont have one available to me. The primary on my BILs motorhome was a Racor filter. Thanks
 
Dhays, look in your engine service manual and let me know what it says about filling the primary (first in the line the tank) just for my info, as I dont have one available to me. The primary on my BILs motorhome was a Racor filter. Thanks

The service manual for the genset doesn't say anything about the primary. The service manual for the cummins main says NOT to prefill any of the filters.
 
Don, I will have to look closely. I didn't crawl into that corner this last weekend. I believe there is a screw on the top, but I don't think there is a pump. It would be nice if there was.
 
One silly question for y'all. When you drain a little fuel out of the bottom of your primary fuel filter to check for water or debris, what do you do with that nasty bit of diesel that is now sitting in your cup or bottle?
Not silly at all. I keep a 2L bottle in the ER for that purpose. When full (takes a while) I return the contents to the earth :eek:, from whence they came. The drainage is initially collected in a white cardboard type disposable coffee cup, so I can see what I drained, then poured into the 2L bottle. Hold the bottle to the light and check for water.
 
Changing the Racors on the dual filter set-up I have, I check bowl for water or crud, so far after 2 years nothing but fuel in there. I take lid off filter to be changed, pull out filter slowly, insert new, change gasket spin top back on. Lever on filters is on non changed filter. I then start engine, idle up to 800-900 rpm, then switch to just changed filter, if engine stumbles or loses rpm the I quickly change lever to other filter. After a few times all is good. Filter on front of engine, I spin off old spin on new, lubed o-ring. I either loosen bleeder plug or leave filter loose. I have someone on bridge turn on key, wait for pump to fill filter and start to dibble out, have them shut off key, tighten bleeder or filter, then restart, and check for leaks. I can fill Racors with my transfer pump, but as yet have not needed to.
 
Changing the Racors on the dual filter set-up I have, I check bowl for water or crud, so far after 2 years nothing but fuel in there. I take lid off filter to be changed, pull out filter slowly, insert new, change gasket spin top back on. Lever on filters is on non changed filter. I then start engine, idle up to 800-900 rpm, then switch to just changed filter, if engine stumbles or loses rpm the I quickly change lever to other filter. After a few times all is good. Filter on front of engine, I spin off old spin on new, lubed o-ring. I either loosen bleeder plug or leave filter loose. I have someone on bridge turn on key, wait for pump to fill filter and start to dibble out, have them shut off key, tighten bleeder or filter, then restart, and check for leaks. I can fill Racors with my transfer pump, but as yet have not needed to.

Thanks. Time to find a sturdy bottle for dirty diesel. I don't recall which engine you have in Rogue. Is it the QSB?
 
Qsb

QSB 330hp w/ electronic Morse controls and 6 kw Northern Lights genset.
 
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