Power steering belt snapped

[Spetz]

Hi guys, For simplicity's sake I'll give everything in bullet points. Car: - 2001 Mitsubishi Mirage coupe - 6A12 MIVEC engine from an FTO - OEM FTO PS cooler is fitted BUT it is obstructed by the front bar and has no airflow basically Symptoms/Problem: - Power steering fluid sprayed everywhere from reservoir - PS pump sounded like a supercharger (quite loud) - Black dust like debris around where PS pump is - Brand new Gates PS belt snapped Conditions during issue - Car was on a race track and was revved to 8,000rpm repeatedly - Belt snapped 45 mins in (end of 3rd 15 minute session) - Fluid was new dextron III - Pump had been making supercharger noise for a long time - The pump spins freely by hand after the belt snapped My thoughts: - Could a faulty PS pump have caused belt slippage and hence belt snap? Would this be the black belt dust near the PS pump? - Was the PS fluid sprayed everywhere from the reservoir due to overheating and could this have caused the belt snap? - One of the lines to/from the PS pump has been leaking fluid. Could this have contributed in any way? And finally are power steering pumps rebuildable? Any advice is greatly appreciated!

 

[RooflessVW]

Originally Posted By: Spetz

- Could a faulty PS pump have caused belt slippage and hence belt snap? Would this be the black belt dust near the PS pump? - Was the PS fluid sprayed everywhere from the reservoir due to overheating and could this have caused the belt snap? - One of the lines to/from the PS pump has been leaking fluid. Could this have contributed in any way? And finally are power steering pumps rebuildable? Any advice is greatly appreciated!

-Yes, and yes. -The belt snapped because the pump was killing itself slowly and eventually seized. -Yes. Air in your power steering system is bad. Cavitation causes heat and friction. PS pumps are rebuildable, but yours probably isn't. Further, your lines and rack are likely contaminated with metal from the lunched pump and will need replaced if they are.

 

[Spetz]

How can I find out whether there is metal from the pump? Can I take the pump apart and look to see if it is in one piece inside? As I really would not want to replace my rack... The lines I assume can be flushed out?

 

[Johnny2Bad]

Oils and coolants eat belts and hoses. Never run with leaking fluids if they get on engine belts or rubber vacuum lines, hoses, rubber brake lines, etc. I could have just said "never run with leaking fluids" since pumps, etc will also die if not properly filled during operation.

 

[Claud]

I think the pump failed because it was run way too fast which also contributed to both overheated and aerated fluid. Unless you have an oversize pulley fitted?. But you're at a race track, if you aren't breaking stuff you aren't trying hard enough. Claud

 

[Colt45ws]

You might look into some sort of underdrive pulley kit to reduce the speed you are spinning the accessories. And put a real cooler on it that is not blocked from air flow.

 

[bblackmon19]

As others have stated the pump is spinning too fast causing cavitation.

 

[javacontour]

Why do you still have power steering on such a small racecar? No PS pump losses means more power to the wheels

 

[Spetz]

Thanks guys. I don't think the PS pump is spinning too fast as it is within the factory rpm limit not to mention other people have not had this issue. The steering was really heavy once the belt snapped. Way too heavy to drive it well, mostly attributed to a large amount of caster. My plan of action is to remove the PS pump, inspect it to ensure that no debris went to the rack, replace the pump, add a proper cooler.

 

[RooflessVW]

Originally Posted By: Spetz

Thanks guys. I don't think the PS pump is spinning too fast as it is within the factory rpm limit not to mention other people have not had this issue. The steering was really heavy once the belt snapped. Way too heavy to drive it well, mostly attributed to a large amount of caster. My plan of action is to remove the PS pump, inspect it to ensure that no debris went to the rack, replace the pump, add a proper cooler.

Sounds like a good plan. I think the root cause of your failure was the leaking pump suction line you already identified. That can and will lead to cavitation and the groaning you were hearing. If you decide you want to underdrive it, a local starter/alternator shop should have a larger diameter pulley that would fit for cheap; no need to get anything billet or fancy.

 

[Spetz]

Would my PS pump be damaged from all this would you say? It spins freely by hand. Also how do I fix the leaks? It is leaking from what seems to be the high pressure out line