oil pressure and shim question
oil pressure and shim question How does shimming the spring in the pump increase pressure......here is why I ask: the spring is there to keep the bypass valve closed so all the oil goes to the motor when the pressure reaches a certain point to over power the spring it opens and bypasses oil.....so lets say the spring opens at 60psi.....the pumps oil pressure doesnt change by adding a shim....it would only keep the the valve from opening.....it now may open at 70psi..........
Please stick to the topic....I know volume is more important than pressure....etc, etc......
I want to know how shimming the spring could possible increase oil pressure at idle......
Thanks Tom
Please stick to the topic....I know volume is more important than pressure....etc, etc......
I want to know how shimming the spring could possible increase oil pressure at idle......
Thanks Tom
it doesn`t.
the point of "shimming" is to give you more pressure
before the bleed off valve opens under load.
to get more PSI at idle or at all you need to flow more,
the only real way to do that is to use a bigger pump or spin it faster.
the point of "shimming" is to give you more pressure
before the bleed off valve opens under load.
to get more PSI at idle or at all you need to flow more,
the only real way to do that is to use a bigger pump or spin it faster.
TECH Resident
Joined: Aug 2004
Posts: 875
Likes: 2
From: Portland Oregon
Shoe is right. At idle the there is not enough pressure to open the bypass at all so you would need a different pump to get more pressure at idle. Or you can think of it like this, if you blocked the bypass so it could not open at all, you would probably have 100 psi at anything over 3000 rpm, but the idle would probably be the same.
How does shimming the spring in the pump increase pressure......here is why I ask: the spring is there to keep the bypass valve closed so all the oil goes to the motor when the pressure reaches a certain point to over power the spring it opens and bypasses oil.....so lets say the spring opens at 60psi.....the pumps oil pressure doesnt change by adding a shim....it would only keep the the valve from opening.....it now may open at 70psi..........
Please stick to the topic....I know volume is more important than pressure....etc, etc......
I want to know how shimming the spring could possible increase oil pressure at idle......
Thanks Tom
Please stick to the topic....I know volume is more important than pressure....etc, etc......
I want to know how shimming the spring could possible increase oil pressure at idle......
Thanks Tom
shimming increases the oil pressure at idle since the installed height is shortened thus the pressure applied by the spring is increased on the valve. the operation of the spring is not only allowing the valve to be shut or closed, depending on pressure the valve can be moving up and down constantly, and keep in mind that the valve is partially open at idle allowing for excess oil to bypass.
volkan
Last edited by vtanju; Oct 12, 2007 at 03:20 PM. Reason: new info
