fuel bleed "knurled knob" (old news)

[Ken Heyman]

I changed my Racor yesterday and it being a beautiful day in Northern Illinois ( near 80), I decided to test my patience. I wanted to see how efficiently opening and closing the knob on the injector pump would bleed a large volume of air form the system. In the past, I have minimized air intrusion by clamping the fuel line  at the filter and also adding fuel to the Racor bowl before reinstalling. This time I simply turned off the fuel at the tank and removed and reinstalled the filters. I primed the system by turning the ignition on in the cockpit (with the battery switch off) and then activating the electric fuel pump with the battery switch down below. I opened and closed and basically played with the knob (on the injector pump). There was quite a bit of pump rattle for a longer period than when I add fuel to the bowl and limit air intrusion but still the whole interval to pressurize and get that rhythmic ticking was only about 4 minutes. --no mess--no fuss with the bleed valve by the secondary filter on the engine. BTW, the Racor bowl filled in about 30 sec. I recommend that those that don't have a self bleeding system try this and ignore the more involved instructions in the engine manual.---just be patient.

Ken

[Mike and Joanne Stimmler]

But Ken, now you've missed all the fun of playing in the diesel fuel.   

On the other hand, maybe you've saved enough time that you can come back to San Diego for another visit. We enjoyed our time with you.

[Ken Heyman]

---as did we Mike/Joanne

BTW how did you make out re: shaft/cutlass bearing.   I sure hope you weren't shafted.

Ken

[Mike and Joanne Stimmler]

We're picking it up tomorrow and everything seems to be OK. I'll post the final results on our original post after we actually get the boat back and spend some time on it this weekend.

[Ron Hill]

Ken : No comment on your "short cut" !!  I will continue to fill my filters with fuel or injector cleaner.
Just remember their are two things in the fuel that will stop a diesel - water and AIR.  A thought

[Ken Heyman]

I agree Ron and this was actually the first time I defied the "bleeding Gods". I was just curious how efficiently that one bleed point could rid the system of air.

Ken

[dbpaul]

Ken

Is this the knurled knob?

paulj

http://picasaweb.google.com/1dbpaul/Fffffff#5455569684065890818

[Stu Jackson]

Ken's become our "resident expert" on fuel bleeding for M25-series engines.  His earlier "Theoretical Engine Bleed" post is here:  http://c34.org/bbs/index.php/topic,2884.0.html

Paul, the later silver engines are self bleeding, you don't have to go through all this nonsense.

My experience is that when the primary fuel filter is changed Ken's ideas work perfectly: filled or unfilled bowl in the Racor, the fuel pump will purge the air.  

When doing the engine mounted secondary, I need to crack the nut on the top of the filter bracket; that's why I installed a fuel pump cut off toggle switch in the engine compartment, it's too far away to use the 1-2-B switch for that purpose.

[Ron Hill]

dbpaul : Thanks for the picture of your M25XP engine made by Westerbeke. It could be an A or a B engine.
Stu is correct about the self bleeding, but you better make darn sure that you crack the nut on the top of your engine fuel filter when you change the filter.  Not too sure if your engine is wired so the lift pump only comes on when you in-gage the glow plugs and then sustains ON when the engine has oil pressure or not.  You probably need to fill your filter with fuel !!

The bottom line is to make sure that the advice you are looking for matches the engine that you have!!! These people are talking about a M25XP made by Universal (Oshkosh, WI)  
I believe that your engine and its wiring could be and probably is differant!!   A thought

[Stu Jackson]

What Ron's talking about is the different wiring for the fuel pumps, discussed at length in this topic: http://c34.org/bbs/index.php/topic,3347.0.html

[dbpaul]

Ken
Did not mean to hijack your thread.
My engine is a M-25XPB.
I was unsure about changing fuel filters and bleeding..... so the best thing was to check the 34Catalina site as always.
The engine manual Pub 200550 1st Edition Jan 2000 came with my boat.
After reading the comments here by Stu and Ron I checked and found an updated manual on-line Pub 200550 Revision 2 Feb 2010.......seems I have a self bleeding system.

from http://www.westerbeke.com/

Thanks everyone

paulj

[Ken Heyman]

Paul

----glad to have you. no apology necessary as there is no pride of ownership with threads. Its always good when someone stimulates a "robust" discussion that morphs away from the original topic.

good luck,

Ken

[gwp]

When replacing racorracor and secondary filter on my m25xp last weekend I opened bleed petcock started engine. It ran for about 5 seconds and died (expectedly). Restarted without incident and all was well??? Was I just lucky? ?? Also....scuse me but did I read in this thread that westerbeke also make there version of the 25 XP?

[Ken Juul]

Westerbeake bought out Universal and now manufactures the "Universal" engines.  I think the proper name for the new engines is Westerbeake - Universal Mxxxx.  In replying to these threads the Westerbeake name usually gets dropped.

The proper way to use the knurled knob:  After changing your filters, open the knob fully.  Activate the electric fuel pump by turning on the key (or jumper in some cases).  The pump will rapidly click then eventually slow down when the air is out of the lines.  Close the knurled knob, the pump should click every couple of seconds.  If desired crack the knurled knob 1/4 to 1/2 turn.  Engine start should then be normal. 

[Stu Jackson]

Ken's right about the knurled knob operation, but please be advised that it is my understanding the M25 engines require (?) the knob to be closed for normal operation, while the M25XP can have the knob cracked (as "self-bleeding").  The later engines are different.  On my M25, once bled, the knob is kept closed all the time.

That's why many times we say: "You NEED to identify which engines you're talking about" and why we suggest you include that in your posts and/or your signatures/avatars.