i purchased my oliver from a machine shop who just rebuilt the motor due to a log puncturing the oil pan. its always ran perfect but it has low oil pressure it will start off at about 20psi and about 15 to 20 minutes later it will drop to 5lbs. i droped the oil pan and checked the bearings and they were all good. i called zimmerman to get a price on a new oil pump and its $450. i was reading im my shop manual and saw it had a pressure relief valve so while i had the pan off i took the relief valve off. it seemed like it was really easy to compress the spring with my finder. should the valve be hard to compress or very easy like mine is?
is this a 4cyl. or 3 cyl. ? the 4cyl. has an adjustable relief valve. Did you plastigauge the crank journals? Is the 20psi at idle or full throttle?
its a 3 cyl. yes the clearences are good. 20 psi at full throttle and while im moving dirt with it about 15 minutes later it has gradually dropped to 5psi.
I did a little story on a bearing leak detector for the wheel tractor guys. Send me your e-mail and phone number and I will e-mail you a copy and talk through it. John
If you have 20psi cold ,then your relief valve should not release to at least 20psi no matter what the engine temp. is . How hot is the engine getting and what weight oil are you using ?
My grandfather always said that 5 psi oil pressure was all you needed on these engines. All it is doing is circulating, not operating hydraulic lifters or such.
Blake
Many of the manuals give a minimum oil psi. of 5 at idle and 15 at governed speed with the engine hot .
i had 10w30 in it then i switched to 10w50 and added an stp oil treatement to try and thicken up the oil and that dident help. i dont think its running to hot its inbetween 160 and 180. once the pressure drops it makes a clanking noise, not a knock but like a radling noise but i think that is just the timing grears. could i get a nother relief valve could that be the problem? does the spring wear out in them? it does not seem like it takes much to compress the spring if i push on it with my fingers.
You could try stretching the spring a little to give some more tension . be sure the relief valve is seating properly. While you have the pan off remove the pump and put the pick up in a parts washer or some kerosene and spin by hand .If you get fluid out the pump should be ok.
I just was cleaning and putting a few items in there correct places. One being a manual for the GO series Hercules. They want the oil pressure to be between 30-35 psi while the engine is running under load. If you have the pan off now is the time to pump it up and see what the problem is. Send me a phone number for details. John
i did that already i pulled it apart streched the spring put the relief valve together and put the pan back on it and it dident make a difference. i have an external oil filter that i bypassed and it made a little bit of a difference like 2-3 pounds
It has been a while since I had the pan off of a GO130 but I remember a copper line on the bottom of the block that carries oil . Since your the engine went down because something went through the oil pan could this line or its connection been cracked ? Is the pick up in good shape and could your pump be cracked or the mounting surface warped ?