Electric Oil Feed and Scavenge Pumps

Turbocharger oil scavenging has always been an issue. You might have 50 psi feeding the turbo but the slightest restriction in the "drain" will immediately send oil past the exhaust seals. In the case of remote mounted turbo systems, or in systems mounted below the engine oil level, some form of positive scavenging has to be engineered. Typically this involved belt driven scavenge pumps from companies like ARE (Avaid), Moroso, Stock Car Products, Peterson , Barnes and others.

Some people like STS (Squires) Turbo, Callaway, Lingenfelter and others use auxillary scavenge systems either mechanical or electric. If you have any sort of drain issue you are going to have oil going past compressor and exhaust seals. The slightest restriction will cause immediate "oiling".

A brief look at how this has been handled by RB Racing and others can be helpful in solving turbocharger issues.

RB Racing has, for more that 28 years, engineered out solutions for turbo oil feed and scavenge systems. Early SOHC Hondas had the pen-ultimate dry sump systems that were bullet-proof. Later on, all the motorcycle engines went wet sump which mixed up clutches, transmissions and everything in the same oil bath. Harleys remained dry-sump systems but, with roller bearing crankshafts, were low pressure designs with lousy dry sump capability and leaking check balls that routinely filled the lower end with oil.

Hondas, with their plain bearings, had excellent oil pressure and you could not kill the turbos due to the superb design of their dry sump oil systems. Oil pressure bypass and back-flow valves were incorporated in the design. We still see 30 year old CB750 SOHC Hondas running around. Early Kawasaki and Suzukis had roller bearing cranks and had problematic turbo feed and drain problems due to low oil pressures and a propensity to send debris to the turbocharger bearings. This lead us to separate electric oil feed systems.

In any of these systems the rider had to avoid stupid mistakes like having the turbo spinning 180,000 rpm and then suddenly killing the engine and pulling in the clutch to do a "plug check". Bye bye turbo bearings.

In the early 1980s we used to put close tolerance Weldon 8000 series 12v electric vane aircraft transfer pumps on our race bikes to feed or scavenge the Rajay and IHI turbochargers. The pumps were extremely sensitive to debris and, if manually activated, were subject to rider brain fade which resulted in destroyed turbocharger bearings when the rider forgot to turn on the pump before a burn-out began. Then came the phone call..."Your turbo went bad". They all lie.

Above is a Weldon Tool 8000 series pump that we used to use. Customers were fond of tearing them up. Our competitors bought a few from us and then we told them to just buy them from Weldon. Model 9200 vane pump pictured below.We moved on.

Clean oil. We tell people the turbo has to be free of debris and they routinely pipe unfiltered oil to the turbocharger. Filters clog or bypass oil when things are cold and all the crap goes to the turbocharger. Don't pump any debris through these.

Lay on the floor for four to six months taking oil pans on and off. Plumb sensitive Magnehelic gauges into various cavities. Take oil pans on and off hundreds of times on different bikes. Drench youself in oil. Machine parts. Remachine parts. Make complicated custom internals, mill fixtutres, cad programs. Test and retest. Bring the parts to market. Then for the next 20 years have people call you on the phone saying they have copied your designs and they want to "buy the oil system". Sell a turbo kit to a customer. He creates a website to tell of his speed conquests and implies that he designed the parts and will tell everyone how he designed the oil system. He never does. He has no knowledge.

Mechanical system that is really difficult to make. We won't go into the details even if waterboarding is authorized. However if you have certified proof that you have waterboarded Dick Cheney we might talk to you.

Tilton has a differential oil pump that people have resorted to who gave up trying to buy "Just the Oil System" from us. Usually it was the Suzuki crowd. Flojet makes pumps like these. These are diaphragm pumps not spur gear nor gerotor pumps. They were never designed to hot pump oil. They work, but there is always a question. 2135 series.

Shurflo makes a similar diaphragm pump that has been used for scavenging of oil on turbochargers. These also were never designed to pump hot oil. 8000 series. One of the people we dealt with in the past has attempted to make a mail order business out of selling these for three times the cost after he gave up trying to figure out our mechanical scavenge system on the Suzuki GSXR series. He tried to pry the information out of us for more than a year. We told him to go sling hamburgers as this would be closer to his engineering expertise. These are not spur gear nor gerotor designs.

VDO has a pump (part # 4050400010001) that was used primarily to send engine oil to an oil cooler. Expensive. Don't ask us where to get them. They are prone to failure in scavenge situations as they were really designed to pump no-aerated oil to coolers.

Jim Feuling has passed on but his oil pumps are still keeping Twin Cam Harleys running better than the oem part. This is gerotor design as opposed to the normal spur gear. Take apart any new Japanese bike and you will find gerotor pumps submerged in their wet-sump systems. They offer smooth oil delivery which is directly related to the number of teeth. They work best submerged, not lifting oil.

Virtually most oil pumps use some form of spur gear design. It's cheap. It works, and it's really good at scavenging oil where it is not submerged in the sump. Tolerant of much abuse, it is a time tested design. Some Harley aftermarket pumps use spur gears to scavenge the crankcase and gerotors to pump the oil. There is a reason for this. VW pump pictured. Straight cut gears are more "noisy" than helical cut so we use helical cut gears.

Bronze helical (quiet) gears. Bronze pump body. No diaphragms to fail. Gear design for maximum scavenge. 12Vdc with splash resistant wiring. Silicone seal Weatherpack connector. Proven in years of use. Metric thread O-ring boss seal (3/8" BSPP) on pump body. 3/8" NPT male entry and exit.

These pumps are suitable for remote turbo systems as oil scavenge pumps. In this case the engine supplies the oil pressure and the pump simply returns the turbo oil to a point above the sump level. They are also suitable as turbo oil feed pumps where gravity drain is possible and is often used where a separate turbo oil supply is used which keeps engine oil and turbo oil separate.

Three pumps are available, Small, Standard and Super. The Standard and Super have the same pump gears, the only difference being the Super pump has a stronger electric motor. Larger just means it's longer and larger in diameter and more powerful. The larger pump is rated at 3 gallons per minute whereas the smaller is rated at 2.6 gpm. The Small pump uses smaller gears than the other two and is rated at 2.0 gpm. All gears are hand-lapped.

If used for pressure feed, both larger pumps will pump up to 40 psi but the Super pump is rated at 40 psi constant whereas the Standard pump is rated at 25 psi constant. It's a question of the torque required. The Small pump is rated at 2 gallons per minute and 20 psi constant. Keep in mind that turbos do not need 3 gallons per minute feed, so to prevent overworking the pump motor the oil must be by-passed back to the feed side of the pump or to the oil reservoir.

Available with viton seal backflow 1 psi check valve for oil scavenge applications. Also available with 20 psi pressure relief valve for oil feed situations. 3/8" NPT female fittings. This is installed on the pump discharge port on a scavenge, or with a "T" on oil feed installations. On oil feed installations the oil is looped back to the feed or bypassed to the supply source.

A 1/8 NPT, 1 psi viton seal check valve is available for the turbo oil feed port. This prevents capillary bleed-down of oil in the engine from entering the turbo after engine shutdown.

Pumps can be ordered with special O-Ring sealed AN8 (1/2" i.d. line) 37 degree flare fittings. The cost is an additional $15.00 per fitting or $30.00 for two. You may choose to use one AN8 fitting on the inlet side and use our 03-1036 1 psi backflow check valve on the pump exit.

Timed delay of pump turn off insures that either scavenge or pump action occurs up to 90 seconds after engine shut down. Incorporates internal 30 amp relay. Simple screwdriver adjustment of the time of the delay from zero to 90 seconds.

The oil scavenge pump has precise bronze gears. If you send any debris through the pump it can either jam or damage the pump gears. Filtering the oil before the turbo or after the turbo is a good idea. Any debris that is in the oil lines that got there during assembly or if you damage an engine and send broken parts everywhere this can ruin a pump the oil is unfiltered. A number of companies make various kinds if screened filters. One from System 1 shown.

All pumps should be on a 10 Amp fused circuit. We offer an inline Weatherpack sealed 10 Amp fuse option for $25.00. Failure to run the pump on a fused circuit will cause pump failure if the pump is jammed by debris.

Everyone wants to go fast and do it themselves. It's often the journey that's the important part.

Customer writes: " I would like to thank you for setting me up with your super scavenge pump 03-1035 for my remote turbo project! I took my 1997 mustang gt and built a twin turbo set-up for it in my back yard. I used your pump for the return oiling. I just wanted you to know how impressed everyone is when they see how well this thing works. I used stainless tubing to help with quality and looks. The set-up completed my project and if it wasn't for the pump set-up my dream would have not become reality.

I drive this car as my daily driver and the pump has worked flawlessly for 12,000 miles now. The car makes 412rwhp and 427ftlbs. to the rear wheels on 8psi. I have enclosed a few pics of my build for you. Thanks for the great product! This winter my goal is to swap out my motor to a built 4v cobra motor and turn up the boost for a goal of 750-1000rwhp. I eventually want to take my daily driver to the salt flats with a goal of 200+ mph. Thanks again I look forward to supporting your business, even my tuner was shocked at the quality of the pump system and loved the idea. Thanks, James M."

03-1040	Oil Scavenge Pump Small, 3/8" NPT Male exit/entry, 3 lbs, 2.0" x 4.5"	$225.00
03-1034	Oil Scavenge Pump Standard, 3/8" NPT Male exit/entry, 5 lbs, 2.5" x 5.5"	$275.00
03-1035	Oil Scavenge Pump Super, 3/8" NPT Male exit/entry, 7.5 lbs, 3.0" x 6.5"	$430.00
03-1036	Viton Check Valve, 3/8" NPT, 1 psi scavenge backflow	$49.50
03-1038	Oil pressure feed relief valve	call
03-1037	Turbo Timer 30 Amp, Timer Delay 0-90 seconds	$49.50
03-1039	Viton Check Valve, 1/8" NPT, 1 psi, turbo oil feed. Bleed-down prevention	$29.50
03-1041	AN8 Fitting Option. Per (1) fitting	$15.00
03-1042	10 Amp Weatherpack (silicone sealed) Inline Fuse Option	$25.00

Note: Some people want to use these pumps on very old motorcycles that have minimal charging systems that will not even support an electric fuel pump. If you do not have enough charging capacity you should not use electric pumps for feed or scavenge.

Secondly: You must use #AN8 (1/2" i.d.), AN10 (5/8" i.d.) or even AN12 (3/4" i.d.) on scavenge lines. Using lines below 1/2" i.d. will result in a dramatic reduction in scavenging.

Mike Geokan's Bonneville Bullet. 132" Watercooled ORCA engine. Dry sump engine (Harley) and Dry Sump Oiling system for the larger Garrett turbocharger. Check out Mike's progress as he goes for 2007 speed records. Viet Nam Vet. Uses electric turbocharger feed pump with timed relay. Mike has used electric oil pump systems from RB Racing for 15 years.

Read more about these dual egt and boost dashes that we manufacture. We use these on our turbo systems and on our race projects. New for 2008.