Killing power steering pumps

[mackconsult]

So I use early 90's power steering pumps belted to a 4 HP electric motor to pump WVO into my centrifuge. It also pumps my clean WVO through a filter so that I can dispense it to my car. At not time is it ever high pressure, its just flow ....

About every 6 to 8 months I have to go to the junk yard and find a new pump because they start to freeze up and become very stiff. I have broke one open and tryed to figure out why the gear pump would become so stiff but still can't figure it out.

Any ideas? I am pretty sure its a seal issue or something. Obviously pumping hot WVO is much different than pumping power steering fluid, but if I could come up with a solution it would be better.

Sail Smart, Sail Hard, Then think about Sailing Fast !!!!!

http://www.mackconsult.com/

Some day I will sell everything, buy a cascade 36 or a cal 40 sailboat, and turn left at the Columbia River Bar !!!!

 

[Compositepro]

Waste vegetable oil contains fatty acids that can react with air and aluminum to form waxes and soaps. You are probably getting waxy deposits and crud under the vanes of the pump that prevent them from sliding freely.

 

[mackconsult]

It's a gear pump


Sail Smart, Sail Hard, Then think about Sailing Fast !!!!!

http://www.mackconsult.com/

Some day I will sell everything, buy a cascade 36 or a cal 40 sailboat, and turn left at the Columbia River Bar !!!!

 

[MikeHalloran]

I have been under the impression that virtually all P/S pumps were variants of vane pumps.

Please post pictures of the interior of the pump you broke apart.

At least tell us what make/model/engine it was removed from.



Mike Halloran
Pembroke Pines, FL, USA

 

[mackconsult]

Let me see what I kind find of my server. Usually when I tear something apart at least take the time to take pictures of it. I can verify that early 90's honda civics used gear pumps for their power steering pumps. That is why I use them for my WVO filtering.

Sail Smart, Sail Hard, Then think about Sailing Fast !!!!!

http://www.mackconsult.com/

Some day I will sell everything, buy a cascade 36 or a cal 40 sailboat, and turn left at the Columbia River Bar !!!!

 

[Compositepro]

Gear pumps for hydraulic power applications have very tight clearances and are not suited for dirty service because they will jam.

 

[mackconsult]

That is a good point. Although I do remember that when I pulled the pump apart last time there was no noticeable buildup or deposits on the gears them selves. I am thinking it is more an issue with bushings, seals, or bearings.

Sail Smart, Sail Hard, Then think about Sailing Fast !!!!!

http://www.mackconsult.com/

Some day I will sell everything, buy a cascade 36 or a cal 40 sailboat, and turn left at the Columbia River Bar !!!!

 

[ornerynorsk]

WVO inherently contains moisture. Corrosion in the bearings?

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[Tmoose]

What are you using the vegetable oil for?

Online infos suggest later Accord pumps are vane type.

This exploded diagram of an alleged 1990 Civic pump does show some intermeshing gears.

http://www.lingshondaparts.com/hpl/images_car/18SH401/imge/E__1900.jpg

I think An autopsy of a failed pump would be required to come up with a real diagnosis.
In the mean time I might perform a non recirculating flush of some kind of petro oil after each use. First to flush out whatever might come out and prevent it doing harm, but also to see //what// comes out. If you're making biodiesel maybe One of the many automotive snake oils might actually be effective at cleaning, but also blend and burn right along with the waste vegetable oil.

 

[mackconsult]

Yep that is it ..... I process the WVO cleaning and drying it then use it as a fuel in my sprinter van. Unfortunately I do not do bio-diesel. Afraid of the methanol and lye, both are not very kind substances and one is quite explosive.



Sail Smart, Sail Hard, Then think about Sailing Fast !!!!!

http://www.mackconsult.com/

Some day I will sell everything, buy a cascade 36 or a cal 40 sailboat, and turn left at the Columbia River Bar !!!!

 

[Tmoose]

http://www.lucasoil.com/products/display_products.sd?catid=2&iid=26

http://www.lucasoil.com/images/medialibrary/MSDS10003-10-10-12.pdf

http://www.lucasoil.com/images/medialibrary/44D56CE8B244DE6C40C6C668131E1823.pdf

 

[Tuckabag]

I suspect your correct, the seals are most likely incompatible with the WVO.
Standard Buna-N (Nitrile) seals are not recommended for use with oils such as Canola (rapeseed), corn or olive oil which I expect would make up a fair content of the WVO you're processing?
I'd wager the seals are swelling around the pump shaft making it difficult to rotate.
Switch the seals out to Viton, or find an alternate pump that uses Viton seals as std.

 

[golfpin]

As usual the various contributors have got it right. Tuckabug has it on the head, I think. Had a similar problem once, as an aside same reason to be very careful of the spec of oils for modern day cars [probably API oil spec SJ onwards causes major problems] Not confined to engines [seals etc] but P/S G,boxes autoboxes, diffs. Here in RSA possibly the biggest selling oil is SAE 40 API spec SG turn back the clock !!!!!!!!! .

My T/W
Golfpin

 

[mackconsult]

Thanks Tuckabag. I designed a urea pump for the Audi Q7 a while back and yeah we had to put all viton seals in. For others information permatech ultrablack was also something that we were able to validate as having a similar resistance to viton as a sealing solution. The validation path was basically everything you could find around an automobile as while as stuff on the common road or garage.

Sail Smart, Sail Hard, Then think about Sailing Fast !!!!!

http://www.mackconsult.com/

Some day I will sell everything, buy a cascade 36 or a cal 40 sailboat, and turn left at the Columbia River Bar !!!!