Hi all I just acquired a new to me snap on mid rise lift the newer table top style but it does not have the original pump with it. I'm wondering if anyone knows what the required pressure is for the lift. I have a ghs pump for a rotary lift that I can use with it but it needs a new pressure regulator and I can get different sizes. So if anyone knows what type of pressure I need that would be awesome thank you so much in advance. Here's a pic of <a href="http://s1315.photobucket.com/user/79f250guy/media/Mobile%20Uploads/IMG_20160322_200005_zpsmvz384bk.jpg.html" target="_blank"><img src="http://i1315.photobucket.com/albums/t600/79f250guy/Mobile%20Uploads/IMG_20160322_200005_zpsmvz384bk.jpg" border="0" alt="Lift photo IMG_20160322_200005_zpsmvz384bk.jpg"/></a>
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Snap on EELR338a mid rise lift pressure
- Thread starter 79f250guy
- Start date
txvwnut
Well-known member
What was the max lifting weight of the lift your pump came from. I had to buy a pump for one my mid-rise lifts and I bought a generic car lift pump setup off eBay. All I had to do was just adjust the relief valve a little and it was up and running. So you might. Get away with using the same regulator.
txvwnut
Well-known member
No I don't know what the pressures are but I will look and see if I can find my manual and see if it says anything about pressure settings. I think these are three inch bore cylinders so 2500 to 3000psi should cover it. My math may be off a little so I could be high on the psi numbers.
I really appreciate the help. I just ended up ordering a 190 bar relief valve so about 2755 psi and I will see how that works. One more question so as far as the force goes. There are 2 3in pistons so does that mean that it the square inch of both pistons times the psi is the force. If so I would think that would be more than plenty right?
txvwnut
Well-known member
That's how I've been told to figure it. Piston diameter times fluid PSI and that should give you a tons in force number.
txvwnut
Well-known member
Just looked at my pump and the relief pressure is set at 3750psi.
oh wow. From doing a little digging looking at new replacements this pump original relief pressure was set at 2250 with different options but i dont know what the max psi is. I guess ill see how it works with the 2750 relief valve. I'm guessing the pump won't handle the 3750. Any chance you could tell me the pump you have in case i would unfortunately have to buy a different pump setup. Thank you for all your help btw!
Area of the bore times pressure gives you force. BUT (and this is a big but), the cylinders are not lifting straight up due to the scissor mechanism. I have the same lift and while it is rated for 6500 lbs it will not do this from a completely folded (bottomed out) position, because the cylinders have very little mechanical advantage in that position (they are pushing nearly horizontally). So I can lift my f-150 pickup off its wheels easily, but as I recently found out, if I remove the wheels and lower it (almost) to the ground it will not pick it back up again. So while the total force (in pounds) from the cylinders is (2 x pi x 1.5" x 1.5" x pressure in psi), the actual lifting force of the mechanism is quite a bit less, especially from the bottom.
Jim
Jim
Well for future reference I installed the 2755psi relief and was not enough. It could barely lift it's self from bottomed out. Very good point about the mechanical advantage. I cant believe it can lift at all with those pistons where they are. Basically horizontal. I guess I'm going to have to some how find out if my pump can handle 3750psi.
txvwnut
Well-known member
oh wow. From doing a little digging looking at new replacements this pump original relief pressure was set at 2250 with different options but i dont know what the max psi is. I guess ill see how it works with the 2750 relief valve. I'm guessing the pump won't handle the 3750. Any chance you could tell me the pump you have in case i would unfortunately have to buy a different pump setup. Thank you for all your help btw!
One my lifts has the stock pump and for the other one I bought a generic pump off of eBay that has no tags or labels on it. The generic one would lift without anything on the lift but I had to adjust the relief valve to get it to lift with a vehicle on the lift.