Power steering pump/pulley

[Kevin G.]

Are the power steering pump and pulley (3834720?)Corvette specific on my sb 72? Somehow the shaft gave out allowing for it move forward about 1/8", causing the pulley to stripout the wooddrift (sp)key and the notch in the pulley. Lucky for me I stopped the motor before any further damage, pulled the belt off and limped home without power steering. Both the pulley and shaft are damaged beyond repair. The rebuild kits that I've seen do not include the shaft, I thought that I might find something at my local you pull it?

Thanks in advance,

Kevin

[Jim S.]

Re: Power steering pump/pulley

The power steering pump driveshafts were all the same in that time frame (up until 1975). There is an internal snap ring that retained the shaft from pulling out of the pump. If the snap ring failed there is a good chance that broken pieces could have damaged the rotor and/or the thrust plate inside the pump.

I believe that you can purchase a core pump as a replacement. You then install the flow control valve, spring, and discharge fitting from your original pump. (This will provide the correct flow and pressure relief.) You also use your original reservoir and studs.

I don't have any info on the pulley.

Jim

[Kevin G.]

Re: Power steering pump/pulley

Jim,
I have disassembled the pump and removed the large retaining spring that holds a large cup shaped cap. This is as far as I was able to take it apart? I haven't been able to figure out how to remove the shaft yet? I'll check for the retaining ring you mentioned. Do you know where to find the core replacement?

Thank you,

Kevin

[Joe L.]

Re: Power steering pump/pulley

Jim,
I have disassembled the pump and removed the large retaining spring that holds a large cup shaped cap. This is as far as I was able to take it apart? I haven't been able to figure out how to remove the shaft yet? I'll check for the retaining ring you mentioned. Do you know where to find the core replacement?

Thank you,

Kevin

Kevin-----


As Jim mentions, you will need to find another pump to salvage the shaft from. You can get one from any 1967 to 1974 Chevrolet vehicle and, likely, any 67-74 GM vehicle. If you don't want to go salvage yard picking, you could buy a rebuilt pump just to get the shaft. A pump without reservoir is the least expensive way to go. Delco #36-516254, aka GM #88985203, is one way to go for about $40-50 bucks. Another is A-1 Cardone #20142. Actually, you could use either of these pumps as complete units in conjunction with your present reservoir and avoid all the rebuilding effort and pitfalls.

The pulley, GM #3834720, is a Corvette-only piece and it's GM-discontinued. However, it is available in reproduction for about 100 bucks.

[Kevin G.]

Re: Power steering pump/pulley

Kevin-----


As Jim mentions, you will need to find another pump to salvage the shaft from. You can get one from any 1967 to 1974 Chevrolet vehicle and, likely, any 67-74 GM vehicle. If you don't want to go salvage yard picking, you could buy a rebuilt pump just to get the shaft. A pump without reservoir is the least expensive way to go. Delco #36-516254, aka GM #88985203, is one way to go for about $40-50 bucks. Another is A-1 Cardone #20142. Actually, you could use either of these pumps as complete units in conjunction with your present reservoir and avoid all the rebuilding effort and pitfalls.

The pulley, GM #3834720, is a Corvette-only piece and it's GM-discontinued. However, it is available in reproduction for about 100 bucks.

Joe,
I spent some time at the yard today, without this information I was unsure that the shafts were exactly the same. An after market pump has been ordered from NAPA and should be here in the morning. This pump should be a direct fit into the reservoir I have? Second, will a 3834720 pulley bolt onto this after market shaft, in the event that I'm able to locate one? I also discovered while searching today, that there is a spacer or washer between the nut on the shaft and the pulley, that is missing on my pump. I have to assume that the previous owner must have removed it causing the gap which in turn created the damage.

Thank you for your help Joe,
Kevin

[Joe L.]

Re: Power steering pump/pulley

Joe,
I spent some time at the yard today, without this information I was unsure that the shafts were exactly the same. An after market pump has been ordered from NAPA and should be here in the morning. This pump should be a direct fit into the reservoir I have? Second, will a 3834720 pulley bolt onto this after market shaft, in the event that I'm able to locate one? I also discovered while searching today, that there is a spacer or washer between the nut on the shaft and the pulley, that is missing on my pump. I have to assume that the previous owner must have removed it causing the gap which in turn created the damage.

Thank you for your help Joe,
Kevin

Kevin-----


If the NAPA piece you ordered was their part number 81693, it should be the equivalent of the part numbers I mentioned previously. In that case, it should replace your pump and be installable onto your reservoir.

There is no spacer which installs between the pulley and the nut. The nut is a special thin locknut and is used without any sort of spacer or washer. The shaft has a slightly tapered end and this fits into a matching slightly tapered orifice in the pulley. The nut then retains the pulley directly to the shaft end vi the threads on the end of the shaft.

[Jim S.]

Re: Power steering pump/pulley

I am not sure if your core pump will come with a woodruff key in the driveshaft slot. It should be 1/8 x 1/2.

Jim