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chuckg5
06-10-2010, 06:43 AM
Hello, I've been lurking here for a year now an finally come out to ask a question because this just came up. for two years, my ford lehman 65hp runs fine. last month put in new racor and secondary filters. No problem. yesterday didn't want to start. switched on the axuliary electric pump (http://www.sailnet.com/forums/autolink.php?id=55&script=showthread&forumid=183), cracked the two bleed screws on the high pressure fuel (http://www.sailnet.com/forums/autolink.php?id=58&script=showthread&forumid=183) pump (http://www.sailnet.com/forums/autolink.php?id=55&script=showthread&forumid=183) - fuel (http://www.sailnet.com/forums/autolink.php?id=58&script=showthread&forumid=183) comes bursting out but no fuel at the ends of fuel line (http://www.sailnet.com/forums/autolink.php?id=75&script=showthread&forumid=183) into the injectors even after tightening the two screws. Wife is top side pushing the starter, turning the engine an fuel pump. Shouldn't I see plenty of fuel at the loosened injector lines (http://www.sailnet.com/forums/autolink.php?id=75&script=showthread&forumid=183)? My mechanic, over the cell phone, miles away believes the fuel pump is fine. afterall, he says , it cost thousands to rebuild - really? the shut off valve was fully pushed in - already went thru that once

Dan Newton
06-10-2010, 07:02 AM
Chuck, I'm far from an expert on this, as you'll soon see, but don't you have to pour some fuel into the filters before you reinstall them and try to crank it up?
We've heard so many air in the fuel line horror stories that we havn't even changed our primary in three years. (I probably shouldn't have admitted to this here at WBF)
Glad you're out of the closet!

Garret
06-10-2010, 07:44 AM
Hi -

Most fuel pumps are far better at pushing than pulling, so if you don't have gravity or pump feed to the injector pump, the line wants to be as full as possible - so you get better efficiency.

If you didn't fill the filter bowls, you probably have a cup or 2 of air in the system. With the quantity the injectors put out, this will take a long time to bleed out. If your aux. pump fills everything to the main pump (which could cost $1000 or more to rebuild by the way), I'd suggest loosening one of the injector lines enough so you can remove it from the injector & aim it into a jar or cup (re-tighten the pump end so it doesn't leak there!). This 1) means less spill when it does start pumping & 2) gives full flow w/ less back pressure. Do not bend the metal lines - doing so will fatigue them & also make it really hard to realign them to go back on the injector.

If you truly have fuel at the main pump, you should get fuel out of the injector lines in 20-30 seconds or so of cranking. It may take a little more, but don't crank for more than 15 seconds or so at a time - let the starter cool a bit (30 sec. to a minute) between cranking episodes.

I am spoiled by my new(ish) Yanmar, as they are self bleeding & don't require all the fun & mess. However, I've seen older engines take a long time to bleed. Mercedes diesels take forever to empty all the air! For engines like this, if you can get the engine to run at all, do so & then bleed them cylinder by cylinder to save wear & tear on the starter. It'll bleed faster too, as even idle speed is way faster than what the starter turns.

HTH

Breakaway
06-10-2010, 08:39 AM
I may be repeating a bit of what Garret said,but try cracking and bleeding the injectors one at a time.

Kevin

chuckg5
06-10-2010, 11:53 AM
thank you. I'm going down to the boat tommorow and retry cracking loose the injector lines. I'm figuring with fuel coming out of the bleed screws, I've just got to prime that pump enough to pump. dam - sometimes swearing helps
i'm a sailor, what the hell

Mike Vogdes
06-10-2010, 12:08 PM
Chuck, you should just give Bob Smith a call and probably get the remedy over the phone... http://www.amerdsl.com/

boattruck
06-10-2010, 12:11 PM
Chuck, No expert, but from the sound of it, repeat your bleeding up to the injector pump. You want to work out any problems before this guy...If, when you get it running, it loses its prime again, you likely need to look to the fuel filters seals, and or the washers/coppers in the fuel line connections, both common areas for leaks, best of luck,Cheers, BT

chuckg5
06-10-2010, 08:16 PM
thank you. it has been awhile since i checked the copper washers and gaskets on the filters an lines. i'm hitt''n it tommorow

starbacca
06-22-2010, 08:06 AM
I just spent at least 30 hours troubleshooting an air/fuel problem on a Perkins 4-108. I would bleed and bleed and bleed and the engine would run for 10 minutes and then quit. Turns out it was a tiny air leak at the diaphram on the lift pump. Just because your fuel pump works does not mean there is no problem.

chuckg5
06-22-2010, 10:00 AM
thanks, starbuck
took off the injector fuel pump off this past friday, first taking everything else off to get to the thing. brought it to stuart, fl. injector service. first thing they said was " wow, haven't seen one of those for a long time" - not what ya want to hear. Then he said 'do ya know those pumps have an oil resevoir to lube the shaft?"
Well, nope- never was told that. probably 30 or so years since that was checked. today he had looked at it and said the reserve was all goopy and by the end of the week he'll get to take it apart.
let ya know