On my VW golf pump I can't figure out why there's no flow out of the hydraulic line fitting which is now just cut off at the hardline connection coming out of the pump with the fitting. I was going to just attach a length of steel reinforced hydraulic hose that I have for the inlet to my DC. The pump has 2 nipples, one larger which would be the inlet, one smaller which figures to be a reservoir connection. But when I attach a hose with VO flow gravity pressured all I get is a flow from the larger to the smaller nipple and nothing out the hydraulic port. So does that mean the pump is no good, or is it something else? This is holding up my CF so I'd really appreciate some clues here.

BTW: yes this thread is revisited - like my attempts at VO running - as I've been assembling a close top barrel CF setup. That involves the CF flowing into the 2" bung on a barrel. The bypass from the CF is able to flow back into the barrel - via a T - with a shutoff to the barrel also allowing an outlet for the finish drain . The CF has a 45 angle on it so it's vertical when the barrel is tipped 45 degrees laterally giving good gravity pressure out the smaller bung. OK I shared - your turn now thanks.

This message has been edited. Last edited by: muzak,

Got to bump this one up - I think the pump is messed up.

First the obvious head-banging thing sometimes overlooked: is the pump drive rotation correct?

Is the volume/rate you get out at the smaller nipple about what you'd expect from the gravity feed? If so the pump impeller/gears may be locked/stripped or the bearings may be shot.

What hapens if you plug the smaller nipple? Maybe on reservoir-type pumps the fluid finds the easy way out? (Mine is not reservoir-type, so I wouldn't know...)

If all else fails you might try googling for a manual or schematic of your pump. I was able to find some good diagrams for mine ('86 Acura).

Is this pump a vane or gear pump? If it's a vane pump you may not be getting enough pressure to turn the CF, especially with colder oil. Also vanes are more likely to fail than gears.

One other thing - with your closed-top setup you will not get the benefits of flash evap for dewatering. I have a (mostly) closed system where I'm using a 120CFM CPU pan to blow air across a cross-fitting below my CF outlet; you might try adding something like that if you want to avoid relying on the CF action alone for dewatering (makes the process take longer).

SunWizard would be my subject-matter-expert-of-choice for these questions...

quote:

Originally posted by jmhpolar:
First the obvious head-banging thing sometimes overlooked: is the pump drive rotation correct?

OMG LOL x 20. That notion hit me about 2 hours after I updated this thread and it was almost enough to pull an all nighter but not quite so thanks for somebody braving my ignorance. I've never seen a pump that would mount with the body in front of the pulley but this is the one from an 80's rabbit. The motor pulley facing the pulley of the pump now spins it correctly! Leave it to the Germans...

Cheers all.

<On the flash evap I'm not quite grasping your setup but I do have a 2" T on the bung with a capped opening that faces outwards at a 90 (and thus could be vented upwards) so what would that require if it was opened up...suction perhaps? >

Attached is a shot of the manifold section of my rig. The cross is below the CF, and the fan blows across it. The fan is plugged into a simple AC/DC transformer that is wired into the pump motor circuit.

Below the cross is a ball valve that I open on pump/CF shutdown to dump the rotor contents to a catch cubie. It's hard to see but the nipple that runs out the other side of the cross to the outlet tee is angled slightly upwards from the cross so the rotor contents don't drain into the drum during dump.

The ventilation exits the top of the outlet tee, which just has 2 small hoses (bypass and pressure-relief discharge) dropped through it and is otherwise open to air. Since the drum is otherwise closed, the vapor should (theoretically ;-) take the easy way out of the top of the outlet tee.

I went for blowing instead of sucking because I didn't want to foul the fan over time with oil and junk.

Someone else on here posted pics of their closed system with a nice high CFM blower fan blowing directly into the drum I think, which should also work, but if you want the most flash evap and aren't going to leave the CF discharge open to the air, you probably want the ventilation to cross the CF outflow as close to the CF as possible, where the oil is hottest and most turbulent.

I also went this route because it let me keep the number of drum penetrations down to 1 (supplying the pump inlet and located in the bottom), and makes good use of the existing bungs.

manifold_front_1.JPG (21 Kb, 10 downloads) CF Rig Manifold - front

Hmm, that tank looks similar to the saddle tank I've moved on to. I notice you separated the inlet for the CF and I'd rather not do that. I've got a post about it up here (trying to heed the topic sections) If anyone would like to explain the dynamics of flash evaporation I'm all ears and thanks for the info.

I'm well aware of it happening and it's a very cool process: when I pump oil out of my collection barrel with a standpipe pump there's great clouds of steam that pour out of even a carboy getting filled and it often surprises me when the oil isn't even warm. But I'm not clear on where that natural process ends if the CF drum has adequate venting - or how an open barrel does more than an opening in a barrel. Clearly condensation can reform on the interior but if you're truly eliminating emulsified water doesn't that water evaporate with enough pressure to force it through any opening that's not sealed air tight?