Great forum! This is incredible for me, an evaluator in a small-population state--Utah--where I am doing driving equipment evaluations infrequently and still must be up on the issues. Steve Townsend, M.A., OTR/L, ATP Utah Center for Assistive Technology 1595 W 500 South Salt Lake City, UT 84104 801-887-9532 >>> "Bradley, Eric" <E-Bradley@xxxxxxxxxxxxxxxx> 5/1/2009 8:52 AM >>> Yes, the use of the backup pump is necessary. If not for the client, for everyone else on the road. If you have an individual that needs the maximum reduced effort steering and lets say the belt on the vehicle breaks, how is the individual going to steer/ control the vehicle? Example: Lets say the belt breaks while on the highway at 70mph and the highway is not divided. The individual using the maximum reduced effort steering is on the inside of a turn and you were on the outside of the turn traveling towards each other and their belt breaks. This individual is not going to be able to stay in their lane and are going to travel into your lane and create a head on collision. If this happened when both vehicles are doing 70 mph that would be at a closure rate of 140mph. I do not know anyone that would like to be in that type of accident. I also inspect quite a few vehicles and the only real problem I have seen is that when the power steering pump get a lot of miles on them the clearances in the pump get greater and the pressure and volume from the power steering pump decreases. If the pump gets weak enough it can/will turn the backup pump on. A thing to remember is that the only difference in reduced effort and zero effort steering is the amount of fluid flow allowed. More flow = less effort, less flow = more effort. The power steering cooler is a good idea, but may not really be necessary. I run 75-100 lap events and run the engine at 7500 rpm and run no power steering cooler and have had zero steering failures. My race car has a steering system that you can adjust the feel/effort and the problem I run into is that when I put the maximum reduced effort valve. The power steering the pump can't keep up with the flow demands and the pump cavitates. When this happens the steering wheel becomes jerky and notchy feeling. When the power steering pump cavitates the fluid flow stop/decrease and becomes Aerated. This will definitly heat the fluid and power steering pump as the fliud is not flowing over the parts cooling them as designed. Eric Bradley From: associates-bounce@xxxxxxxxxxxxx [mailto:associates-bounce@xxxxxxxxxxxxx] On Behalf Of John Anschutz Sent: Thursday, April 30, 2009 8:07 PM To: associates@xxxxxxxxxxxxx Subject: [associates] Re: Back up steering systems What a great topic. I am not sure I know the answer. I sometimes wonder if the backup pump is a backup for a problem that could be prevented. I have a van with zero effort steering. It suffers from stress due to over-heating of the steering fluid. I think the original problem stemmed from two sources. 1. If the engine is running and the Van is parked or at idle for an extended time with the wheels turned it will overheat the steering fluid. 2. Sometimes with new drivers or in an eval our evaluators want to really check out the client's turning abilities before ever going on the road. Let me tell you that the rate of change in wheel direction with a Zero Effort (sorry I am old school - Maximum reduced effort) steering is far greater than what is typical in traditional steering. It really heats up the oil. Overheats. The problem is that if the oil gets too hot seals can fail and you can have a lot of damage and you may have need for a back up system. Would a more modern approach be something like installing a steering fluid cooler like they do in some dirt track racing cars where they put great demands on steering? I think DSI uses a cooler in their system. Also, if we had a temperature monitor on the fluid then a dangerous or damaging situation could most likely be avoided all together. If you can really do that then would you still need a backup pump? Seems like the consumer would appreciate the ability to avoid major repair. This is kind of like seeing that your car is overheating and you stop before you ruin the engine. In this case the complicating factor is that steering is so much more important for safety to the consumer. It would be nice if the consumer can avoid a problem and a failure of any kind. Once you have a need for the backup you are back to oil squirting somewhere and you could have a fire situation that you mentioned. Thanks again & I look forward to seeing other thoughts. John Anschutz Please don't anyone change there practices based on our discussion. We are just brainstorming. Please don't go out and change your practices based on these comments. On Apr 30, 2009, at 6:51 PM, cbckj@xxxxxxx wrote: Thanks for a forum to discuss our issues. It is really appreciated. I am an inspector and have the unique opportunity to poke my head into, and around a lot of converted vehicles. I am hoping to solicit opinions and guidance from this learned group of professionals, and to have some input into the general NMEDA community. Please understand, I just want to stimulate some dialogue, not propose policy...case in point: During inspections I have found that back up steering pumps are mounted in areas that are subject to damage even from minor impacts. My concern is that these systems could rupture and leak with high pressure flammable fluids spraying into the engine compartment. The pumps are frequently mounted in the front bumper. Back up steering systems have not changed in basic design for over 25 years. One of my discussion points, (besides location change and design) is the actual need for these systems. I have seen more problems with back up steering systems than I have heard reports that they serve their intended purpose. The maintenance and installation issues are numerous. Is the intended safety of this device worth the problems? I'm looking forward to your comments. C. Kerry Jones "The Space Between" cbckj@xxxxxxx The documents accompanying this transmission contain confidential information belonging to the sender that is legally privileged. This information is intended only for the use of the individuals or entity named above. The authorized recipient of this information is prohibited from disclosing the information to any other party and is required to destroy the information after its stated need has been fulfilled. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution or the taking of any action in reliance on the contents of this information is prohibited. If you have received this in error, please notify the sender immediately at the address above to arrange for the return of the original documents. Thank you Can't afford a new spring wardrobe? Go shopping in your closet instead ( http://www.stylelist.com/spring-fashion/spring-style/shopping-in-your-closet?ncid=emlweusstyl00000001 )!