Dry-sump construction

[brett_celicacoupe]

yep i found that website earlier but i fear their prices if i was to call them .

its basically a money thing. if i can do it cheap enough then i will go dry sump, otherwise ill wing the original wet sump.

i tried my 5me air pump but i think its stuffed. i had a 18rc one a while back and it felt like it could pull a good vacuum. im trying to hunt down another 18r pollution air pump now to test this.

another interesting attachment to teh 5me pump is a 1-way valve. this could stop the oil running back through the scavenger pump to the sump if i was to leave it on.

thanks for the reply bill

[Billzilla]

yep i found that website earlier but i fear their prices if i was to call them .

its basically a money thing. if i can do it cheap enough then i will go dry sump, otherwise ill wing the original wet sump.

i tried my 5me air pump but i think its stuffed. i had a 18rc one a while back and it felt like it could pull a good vacuum. im trying to hunt down another 18r pollution air pump now to test this.

another interesting attachment to teh 5me pump is a 1-way valve. this could stop the oil running back through the scavenger pump to the sump if i was to leave it on.

thanks for the reply bill

A single-stage pump is something like $900 or so, a dual-stage (which is the one you need) is about $1,100 I think.
Max revs on them is about 4,500.

[thechuckster]

i think the 1-way valve would be quite restrictive ... but novel idea.

those pumps don't produce a huge amount of pressure - they're a volume pump. Some of the older ones (barrel with the shaft offset from the centre and with sprung vanes for seals) are much like vacuum pumps found in diary equipment.

[Billzilla]

i think the 1-way valve would be quite restrictive ... but novel idea

... and not really needed. All you do is angle the pipes so the gears in the pump stay 'wet' with oil, so it'll pump right away after the engine cranks.

[brett_celicacoupe]

a dual-stage (which is the one you need)

please elaborate on this. i cant see in the text above where it indicates i need one for my purposes (dual vs single stage)

[Billzilla]

please elaborate on this. i cant see in the text above where it indicates i need one for my purposes (dual vs single stage)

It's the problem of volume Vs revs for the pump.
I rang that BDG mob and asked how much volume the pump had and the maximum revs it could do. Turns out the max revs they're happy with continuous is about 4,500rpm. They'll briefly run faster but they suffer from inlet cavitation problems.
So you have to plan on running them slower, and if you do that then you're going to come up short on the volume you need - hence a two-stage pump.
And with frictional losses going up with the square of the revs compared to two-stage pumps making twice as much friction, there's probably a slight benefit in running a big(ger) pump slower.

[thechuckster]

bill - do you still use the engine oil pump for the pressure supply? or is there are third stage on your pump providing positive pressure supply?

[Billzilla]

bill - do you still use the engine oil pump for the pressure supply? or is there are third stage on your pump providing positive pressure supply?

Straight from the bottom of the scavenge tank into the side of the existing oil pump on the front of the engine ->



Useless trivia - the oil pump gears in a Suzuki G13B twin cam are exactly the same as a 4AGE.

[Billzilla]

Some other more recent photos, as the car is undergoing a major rebuild at the moment and I've changed a few things.

Here's the front of the engine without a lot of the crap in the way ->



You can see the modified pump inlet there.

And I also turned the scavenge pump around and eliminated the alternator. It wasn't used so was just dead-weight anyway. The only hassle is that the pump inlet is now at the top and the outlet at the bottom. It has to be that way because of the way the pump turns.



This diagram shows why ->

[oldcorollas]

?? if your gears are like in the pic... and the engine spins the normal direction (ie crank turning clockwise when viewd from the front of car... and you are turning the gear that is left in that pic.... then inlet is at bottom?

if not, make new endplates and make RHS gear the driven one

[Billzilla]

?? if your gears are like in the pic... and the engine spins the normal direction (ie crank turning clockwise when viewd from the front of car... and you are turning the gear that is left in that pic.... then inlet is at bottom?

if not, make new endplates and make RHS gear the driven one

Damn!
I thought I worked it out ....

[rick q]

I've been told by a bloke who races clubmans in NZ that a couple over there are using the two stage power steering pump off the V6 Camry (one stage for P'steer - the other for the hydraulic engine fan) on 3SGE's.

It's used as a two stage scavenge, with the existing engine oil pump as pressure. The power steering pump can't be run at more than half engine speed apparently, because cavitation causes it to stop pumping at higher revs - a couple have apparently lost engines this way.

See http://www.toymods.net/forums/showth...t=28604&page=2

[thepeter]

Thanks, this info will no doubt come in handy as I've begun prep for dry-sumping my 4a mid next year.

I'm using cut up hard-drive magnets in the sump plate as the 'catch' field is broader than a standard/cobalt magnet. Grabs up a whole lot more metal shards.

Also, the mesh idea is great. though the use to fine of a mesh would cause restriction, and/or possibly frothing the oil even more?

[Billzilla]

Thanks, this info will no doubt come in handy as I've begun prep for dry-sumping my 4a mid next year.

I'm using cut up hard-drive magnets in the sump plate as the 'catch' field is broader than a standard/cobalt magnet. Grabs up a whole lot more metal shards.

Also, the mesh idea is great. though the use to fine of a mesh would cause restriction, and/or possibly frothing the oil even more?

Make sure the magnets aren't too fragile and break-up.
And yes, the mesh has to be a bit coarse, it's mainly to stop the rocks, not the finer partcles.

[brett_celicacoupe]

in this photo mic posted, http://img167.imageshack.us/img167/2...bddsssadu9.gif , where the oil from the tank goes through the pump and into the engine, is it still going through the engine's internal pressure pump?.

if so will there be relatively high pressures in the line between the 3stage scavenge pump and the engine's pump? this is given that the scavenge pump will be moving a higher volume of oil then the internal pump.

are all your (bill) systems running gravity fed oil from the tank to the internal oil pump?