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Roachie
02-24-2009, 22:32
G'day from down-under,

I'd been having a bit of diesel dripping from the mechanical fuel pump on my n/a 6.5 and suggested to my spanner-man that we should be able to do away with it altogether.

I also have 2 electric lift pumps (one behind the "top hat" in the middle of the "V" and the other down the back above the main tank), so there should be no need for the mechanical lift pump.

Just wondering if other owners have also done away with the mech pump?

Regards,

Roachie

simon
02-24-2009, 23:12
G'day from the far north[Can].

with 3 lift pumps on it you could pump crude.

why 3 LP's? but you can skip the mech pump, altough they are less failprone than electr ones. you can leave it on to block the hole. if you dont want to have it rattling along, take the pushrod out.

hope this helps.

Roachie
02-25-2009, 00:53
Thanks Simon.

I guess I've done a bit of overkill by adding the 2nd electric pump, but the rig had the mechanical + one electric pump when I bought it.

It runs 2 fuel fiters plus a de-bug unit ( see www.morison.com.au (http://www.morison.com.au) ) to combat any problems from algae etc which can sometimes be a concern in the outback regions of Australia.

With this extra restriction, I figured if I added a 2nd electric pump down the rear, it would ensure that I was pushing the fuel up the front. The new pump is just a small Facet pump of about 5psi capability.

Thanks again,

Roachie

DmaxMaverick
02-25-2009, 01:12
For your engine, 5 PSI is about all you need or want. Over 10 PSI, you can have IP issues (skews injection timing). Any pressure more than zero is good (under all conditions, of course).

I am no a fan of electric pumps. Especially when reliability is needed. Electrics fail often and without notice, comparatively. Electrics are good for engine-off priming, but mechanicals excel beyond that. I suggest replacing your mechanical with a mechanical. No harm in having an electric in stand-by, though.

Roachie
02-25-2009, 01:27
For your engine, 5 PSI is about all you need or want. Over 10 PSI, you can have IP issues (skews injection timing). Any pressure more than zero is good (under all conditions, of course).

I am no a fan of electric pumps. Especially when reliability is needed. Electrics fail often and without notice, comparatively. Electrics are good for engine-off priming, but mechanicals excel beyond that. I suggest replacing your mechanical with a mechanical. No harm in having an electric in stand-by, though.


Thanks for the advice Dmax

Cheers,
Roachie