argh! another fuel leak on my Yanmar!

Jul 7, 2004
8,492
Hunter 30T Cheney, KS
I tried to get out today, we finally got a break from the rain. My 2GM20F started right up but fuel was all over the stbd side of the engine. Turned out to be a leaking bleeder screw on the fuel filter housing. It looks like the nylon washer is gone, but worse than that, the screw just spins and never tightens. Hardly any force applied and it just spins like the threads are gone.
Anyone else ever experience this? Looks like I need a new filter housing !
I haven't removed it yet.
 
Jan 5, 2017
2,401
Beneteau First 38 Lyall Harbour Saturna Island
Looks like I need a new filter housing !
I haven't removed it yet.
Is it the housing threads that are gone or the screw? Could you re-tap to a larger size? I'm having a small leak problem myself. Unfortunately between the high pressure pump and the injectors. Hopefully the right parts will be here tomorrow!
 
Jul 7, 2004
8,492
Hunter 30T Cheney, KS
I've done further reading. Looks common. The fix is to oversize the housing and use a larger plug/bolt. Not really my MO. I'm pricing a new housing. This has not been a good season.
 
Jan 5, 2017
2,401
Beneteau First 38 Lyall Harbour Saturna Island
Tapping to the next size up would take just a few min. and cost next to nothing until the new part comes. Anything to get going again.
 
Jul 7, 2004
8,492
Hunter 30T Cheney, KS
Good point Michael. I should have pulled the old housing off. Now I think that by the time I get it patched the new one will be in.
 
Jan 5, 2017
2,401
Beneteau First 38 Lyall Harbour Saturna Island
As long as your supply of parts is close by! I'm out in the wilds of the west coast of Vancouver Island at the moment so I either made do or wait for them to fly in parts. The high pressure side is a little harder to stop those pesky leaks.
 
Jul 7, 2004
8,492
Hunter 30T Cheney, KS
Not close, but fast. I found some fuel line that needs replacing as well.
I loved Vancouver Island. Sorry we got there so late and had to catch the last ferry.
 
Jan 5, 2017
2,401
Beneteau First 38 Lyall Harbour Saturna Island
I loved Vancouver Island.
I agree it's a pretty nice place. You'll have to come back and spend more time. Good luck with your leak.
Wonderful things, boats. They sure can stop us from getting bored!
 

HMT2

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Mar 20, 2014
900
Hunter 31 828 Shoreacres, TX
I've done further reading. Looks common. The fix is to oversize the housing and use a larger plug/bolt. Not really my MO. I'm pricing a new housing. This has not been a good season.
Had the same problem if you are talking about the secondary filter. I just replaceded the whole unit. It took about fifteen minutes and as I recall it cost less than fifty bucks. My supplier said it was very common for that bleeder screw to crap out.
 
Jul 7, 2004
8,492
Hunter 30T Cheney, KS
Had the same problem if you are talking about the secondary filter. I just replaceded the whole unit. It took about fifteen minutes and as I recall it cost less than fifty bucks. My supplier said it was very common for that bleeder screw to crap out.
That's my plan. It is the secondary filter on the engine itself. It looks like a pretty simple job on my Hunter. Access is excellent. I'm so glad to read that they aren't going to rape me on the cost of the housing. Thanks for the response!
 
Jul 7, 2004
8,492
Hunter 30T Cheney, KS
Just ordered the new housing and banjo fitting washers from Niemiec. About $56 plus shipping. It will arrive the middle of the week. I can live with that.
If there is a pearl of wisdom to pass on. Bob says it's a common problem. The nylon washer wears thin over time and use so the plug becomes too short and will stretch the threads. He recommends replacing the washer once in a while and only use a small Phillips so you don't over torque the plug.
 
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May 24, 2004
7,174
CC 30 South Florida
Yes, we keep spare screws. A temporary fix could be driving a slightly larger screw with a seal washer into the housing.
 

HMT2

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Mar 20, 2014
900
Hunter 31 828 Shoreacres, TX
Be sure to tighten down hard on those copper banjo fittings. I didn’t the first two times and had a very small leak at the banjo fitting.
 
Jan 30, 2012
1,144
Nor'Sea 27 "Kiwanda" Portland/ Anacortes
. . . a leaking bleeder screw on the fuel filter housing. It looks like the nylon washer is gone, but worse than that, the screw just spins and never tightens. . . . Looks like I need a new filter housing!
There are 2 - 8mm and 6 mm. The smaller is the one sealed with a polyethelene washer. There is not enough room in the casting to tap to the next size - that is the thicker area where the holes are tapped are is not wide enough for larger holes and finding larger drilled screws is a problem too.

Renew the threads with a helicoil instead. That way the threads will be stainless instead of aluminum. If you don't feel comfortable at this your local automotive machine shop will do it for you.

Charles
 
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Jul 7, 2004
8,492
Hunter 30T Cheney, KS
Rather than dedicate a new thread, does anyone know the ID of the fuel line that runs from the primary filter to the fuel pump? It's old and needing replacement. Thanks!

New fuel filter housing should arrive tomorrow!
 
Jan 30, 2012
1,144
Nor'Sea 27 "Kiwanda" Portland/ Anacortes
Standard is 5/16 but I will go measure. Be right back.

Charles

Back now -- 5/16 from primary filter to lift pump is the norm. I have some in the shop now and some of those are 1/4. So -- I guess measure the banjo fitting barb at the lift pump and the one at primary filter housing output and make a descision.
 
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SG

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Feb 11, 2017
1,670
J/Boat J/160 Annapolis
I'd use a heli-coil.

You don't need a drill rig as long as can do it otherwise. Look for some other YouTube videos.

 
Jan 30, 2012
1,144
Nor'Sea 27 "Kiwanda" Portland/ Anacortes
Thanks Charles!
You are welcome. Send me the old top of the canister and I will send it back fixed. That way you get a better top - a spare. Remember the replacement still has aluminum threads.

Charles