Another 470 question about power steering pump

"I recently bought an aftermar

"I recently bought an aftermarket alternator kit and Pertronix electronic ignition system for my 1988 3.7lx 180hp (470). In the process of putting the alternator kit on the engine I had to remove the power steering pump to attach high pressure hose fitting to power steering pump in order to have enough room to work. Anyway, I noticed that the power steering pump had a little front to back play when I pulled on the pulley in and out away from pump housing. Question: Should the pump have any forward,backward play. There is no side to side play just front to back. I just don't want to mount the pump and end up broke down on the water. Finally, the power steering pump is a NLA part and if you could get a new/old part they run around $350. What is the difference between an automotive power steering pump and a marine power steering pump? I could almost swear it looks like the power steering pump out of a 1980's Ford 351-M less the mounting bracket. Do marine power assist pumps run at the same psi as auto power steering pumps? Any help would be appreciated! Thanks, Tom"

"Yes, some do look identical.

"Yes, some do look identical. Many of these pumps are basically the same as an automotive unit.... but remember the uniqueness of the 470!
Some of the automotive over-haul kits may work.

The end play may not be an issue...... Why not run it and see if this causes a leak? It can't be all that difficult to remove later on!

."

"Thanks Ricardo E, I was going

"Thanks Ricardo E, I was going to test it but was not sure if it would be a problem. It is probably the original pump and I am adding the Hunn-Finn aftermarket alternator kit and I am hoping it will work alright. I had to order a new high pressure line and found the low pressure line at a local boat yard. The guy told me that the marine pumps run at around 800psi and are different from the auto pumps but the pump housing looks identical. I was afraid to put an auto power steering pump on in case it might blow out something in the power assist. The pump has been sitting around for quite some time. I drained it about a year ago,washed it out with soap and water and blew it out with high pressure air so there is absolutely no oil in the housing at this time. I guess I will have to try it out but hate like heck to fill up with oil and have it all over the place. lol. Finally, what kind of oil do you guys generally run in these systems and how much do they hold? Thanks Ricardo E,
Tom"

Power Steering on boats use po

Power Steering on boats use power steering fluid.. you could hook up a pressure gauge to them(with a T fitting) and see what you get. I beleive them to be the same.

"Sorry to ask such such a sill

"Sorry to ask such such a silly question Brian but was not sure what the Mercruiser Power Assist required. I kind of figured it would be power steering fluid but wasn't sure. thanks, Tom"

"Silly questions don't exi

"Silly questions don't exist, thats a misnomer. "