KKtrips Posted December 7, 2007 Share Posted December 7, 2007 My oil pressure gauge is off the hems tho, over 100 which is off the gauge! Good ol high flow high pressure pump which was completly overkill to install! IMHO - if you have a hi volume oil pump you should not be getting 100psi - if you are, you have WAY too much volume or blocked oil galleries, anything over 80 will start to overpressurize the bearings and cause the surface to erode away.. I am NOT an engine builder but this is a general rule I have always worked to.. My general rule is oil pressure should be 60psi when hot and never more than 80psi when cold. PS - there is no such thing as a high pressure oil pump - it is the size of the oil galleries that determine your oil pressure. It is a high volume oil pump you talking about.. ie - LOTS of pressure becasue of the flow restriction and the volume trying to get up there.. Think something like - Hi Volume = trying to squeeze a whole salami up the eye of your pee-pee nuff said Quote Link to comment Share on other sites More sharing options...
Unclejake Posted December 7, 2007 Share Posted December 7, 2007 BDA makes a good point. The rule of thumb my engine builder uses is that you need 10psi for every 1,000rpm. I think over 7,000rpm that is getting a bit silly - and of course an oil pump needs horsepower to drive it so more oil pressure = less driveline power (until the motor blows) The race engine is set to about 65 psi hot @ 7,000 rpm. Quote Link to comment Share on other sites More sharing options...
thegreatestben Posted December 7, 2007 Share Posted December 7, 2007 your clutch is doing the same thing my chasers is doing. pain in the arse. Interesting to see if bigger master cylinder is the fix. Mint progress anywho! Quote Link to comment Share on other sites More sharing options...
Gaz Posted December 7, 2007 Share Posted December 7, 2007 Oh thought it was the pump making it high. I have a huge sump also. 6litres so that could be doing it? I knew about the too high oil pressure buzz but didnt know if this was TOO high or not. If I was going to try remedy this high OP shall I decrease volumn in sump? Gaz Quote Link to comment Share on other sites More sharing options...
thminiman Posted December 7, 2007 Share Posted December 7, 2007 nah that shouldnt matter, tank (sump) volume is irrelevant as there shouldnt be pressure in the system until after the pump perhaps having changed the pump to a higher volume one, you've made the ooil lines too small to suit it, hence the increase in pressure, or, as someone said there may just be a blockage in one of the lines or galleries Quote Link to comment Share on other sites More sharing options...
Gaz Posted December 8, 2007 Share Posted December 8, 2007 PS - there is no such thing as a high pressure oil pump - it is the size of the oil galleries that determine your oil pressure. It is a high volume oil pump you talking about.. Done a bit of research into it as It def is a problem. The pump is actually high flow and high pressure. The relief valve in the pump determines the pressure, the flow rate is determined by the design of the pump. Yes excess flow can cause pressure to rise but the relief valve should handle it. The pump which is brought from Burtons is sold as high flow, high pressure. You can buy high pressure, or high flow, or both like I did. Going to remove pump this week tho and put a standard one in to drop OP. Quote Link to comment Share on other sites More sharing options...
Gaz Posted December 8, 2007 Share Posted December 8, 2007 your clutch is doing the same thing my chasers is doing.pain in the arse. Interesting to see if bigger master cylinder is the fix. Mint progress anywho! Bigger cylinder will fix it but cheaper option might be to sleave the slave. Going to try that this week. Quote Link to comment Share on other sites More sharing options...
Blair Posted December 9, 2007 Share Posted December 9, 2007 Bigger cylinder will fix it but cheaper option might be to sleave the slave. Going to try that this week. Somehow I dont think a bigger cylinder will fix it. I bet its the travel in the fork set up. Re - adjust it. Quote Link to comment Share on other sites More sharing options...
Gaz Posted December 9, 2007 Share Posted December 9, 2007 Why is that? Wont a bigger cylinder push more oil down? My clutch works fine when the pedal is pumped a few times before starting the car/using it. This shows it is not the fork but a pressure prob. Quote Link to comment Share on other sites More sharing options...
thminiman Posted December 9, 2007 Share Posted December 9, 2007 not a leak somewhere, bad seals or badly adjusted is it? i had the same problem on thmini and turned out i'd been a newb when i bled the clutch and the adjustment screw was in too far Quote Link to comment Share on other sites More sharing options...
Blair Posted December 9, 2007 Share Posted December 9, 2007 Why is that? Wont a bigger cylinder push more oil down? My clutch works fine when the pedal is pumped a few times before starting the car/using it. This shows it is not the fork but a pressure prob. Sounds like it is "bypassing" in the cylinder and a bigger cylinder will only give you more volume and less pressure small cylinder give less volume and more pressure bigger is not always best when it comes to hydrolic oil and cylinders whether its to do with clutches or master cylinders on brakes. What you are best to do is either get another cylinder that is the same as th one you are using now or get your one re - sleeved. Quote Link to comment Share on other sites More sharing options...
Blair Posted December 9, 2007 Share Posted December 9, 2007 Also how are you bleeding the clutch??? ie rapid pumping and then opening the bleeder nipple or with an open bleeder nipple and pumping slowly, then closing once you are no longer getting any air bubbles??? As you may still have air in the system if you are using the rapid pumping method, which if you havnt guessed isnt the one to be using. Quote Link to comment Share on other sites More sharing options...
Gaz Posted December 9, 2007 Share Posted December 9, 2007 What you are best to do is either get another cylinder that is the same as th one you are using now or get your one re - sleeved. What will this do? If the one I have is leaking I would see oil woulnt I? Sorry, bit confused by what ya mean. Also I bled it the right way with slow pumps. Gaz Quote Link to comment Share on other sites More sharing options...
Blair Posted December 9, 2007 Share Posted December 9, 2007 What will this do? If the one I have is leaking I would see oil woulnt I? Sorry, bit confused by what ya mean.Also I bled it the right way with slow pumps. Gaz It could be "bypassing" in either cylinder(master or slave) and if it was you wouldnt see any fluid as what happens is, once the car is left over night or for acouple of days the fluid will flow back into the reservoir. So no you would see any fluid leak. So when which you jump back in the car and have to pump up the pedal to get the fluid that has leaked out(back into reservoir) so you have pressure again and like you say the clutch is working fine. If it is "bypassing" then you will have to get either or both looked at. I still think that it is an adjustment issue at the clutch fork. Have you use a standard clutch and pressure plate??? As the gap between the two is very important. I also see that you are using a lighten flywheel does it have a "step" in it??? As the "step" could be wrong?? I know that if I am 0.1 of a mm out when I machine a flywheel the clutch will not operate correctly. Also it could be that you clutch has some oil on it from when you had that weeee leak from the rear seal?? I hope this is helping and not confusing you more. Quote Link to comment Share on other sites More sharing options...
Gaz Posted December 9, 2007 Share Posted December 9, 2007 Nah its good as. I just thought larger would fix but might as well eliminate other areas first as it would make sense. The clutch did get a bit of oil on it but only drops. I cleaned them off with either/engine start. The car/clutch is fully usable and does'nt slip once the pressure is up. Thinking this indicates I cleaned it off enough. Am using the standard clutch and plate, no step in flywheel. The setup is usually cable type, I dont think there are any type9 standard hyraulic systems. The slave is new so I wont look there just yet. I have a rekit seal etc here for the master which I could chuck in to see if that eliminates the problem. Can check bore etc then at same time.. Quote Link to comment Share on other sites More sharing options...
Blair Posted December 11, 2007 Share Posted December 11, 2007 Cool. If you need any more help and shit, just give me a yell. Quote Link to comment Share on other sites More sharing options...
d.p.n.s Posted December 13, 2007 Share Posted December 13, 2007 looking good mate. Quote Link to comment Share on other sites More sharing options...
Gaz Posted December 13, 2007 Share Posted December 13, 2007 Cert 2moro Quote Link to comment Share on other sites More sharing options...
Unclejake Posted December 13, 2007 Share Posted December 13, 2007 Good luck mang. It looks HOT! Quote Link to comment Share on other sites More sharing options...
Snoozin Posted December 13, 2007 Share Posted December 13, 2007 Best of luck for the cert fella, the car is looking gorgeous Quote Link to comment Share on other sites More sharing options...
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