First time start up. 10psi oil pressure HELP
11-25-2014, 12:46 PM
#22
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The basic principals of bearing coating is correct as you have explained but you are wrong about pressure not separating the friction surfaces. The more load that is applied, the more pressure needed in order to maintain your pillow of oil between the two surfaces. This is basic stuff. As many motors as you've put together and your going to tell this guy 10psi hot idle is ok? Will it work? Sure becuase its under no load. Is it anywhere near desirable? Absolutely not. My freshly built boost built motor hot idles almost 20 psi more than this and you can believe my tolerances are loose. This is with 15W30. OP I wish I had more advise for you but I stick by my guns.10psi hot idle is unacceptable in my book.
11-25-2014, 12:59 PM
#24
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well **** tacos. I guess I just get the car finished and then pull the engine and break it down worst case. I mean you gotta pay to play right? Lolol I ******* hate life
11-25-2014, 09:28 PM
#25
The basic principals of bearing coating is correct as you have explained but you are wrong about pressure not separating the friction surfaces. The more load that is applied, the more pressure needed in order to maintain your pillow of oil between the two surfaces. This is basic stuff. As many motors as you've put together and your going to tell this guy 10psi hot idle is ok? Will it work? Sure becuase its under no load. Is it anywhere near desirable? Absolutely not. My freshly built boost built motor hot idles almost 20 psi more than this and you can believe my tolerances are loose. This is with 15W30.
OP I wish I had more advise for you but I stick by my guns.10psi hot idle is unacceptable in my book.
OP I wish I had more advise for you but I stick by my guns.10psi hot idle is unacceptable in my book.
Not really as long as were talking about just a start up and seeing no oil pressure and shutting it down. If your leaving it idle for a length of time, then obviously that is not a good idea for any length of time. Seen a lot of ppl leave the barbell out of the back or O-ring pickup tube etc... and had started the car multiple times after trouble shooting a few things each time. After fixing issues with the car they ran great had great oil pressure and most are still on the road.
11-25-2014, 09:53 PM
#26
Well everyone is entitled to there opinion for sure. And I'm not saying nothing is wrong with it. But even GM won't do anything about a motor with 10-12lbs of oil pressure at hot idle! Ask me how I know! But yeah its not the warm fuzzy feelling you going to get with say 40psi of hot idle. I had a motor that HKE and I put together with really large clearances 2.7-3.0 thou. and an aluminum block will grow another 1.0 thou. when hot so effectively 3.7-4.0. Plus they just bleed oil from the lifter bores for the same reason and everywhere in general. car had 9-10lbs of hot idle with 20W50. WOT it was around 40-45lbs. Lived for two years making north of 1K+ rwhp. Actually longer than that as we only took it apart to change the reluctor as it was the same motor that I ran for a 1.5-2yrs earlier in my Black SS making almost 1200rwhp in that car. And was still running fine when I changed motors. That was just to provide you with a direct example of what I mean by 10 PSI being ok as long as it is you know everything is good and working correctly. So with that said I would do some checking of a few things before running it hard etc... Not really as long as were talking about just a start up and seeing no oil pressure and shutting it down. If your leaving it idle for a length of time, then obviously that is not a good idea for any length of time. Seen a lot of ppl leave the barbell out of the back or O-ring pickup tube etc... and had started the car multiple times after trouble shooting a few things each time. After fixing issues with the car they ran great had great oil pressure and most are still on the road.
As far as him not trashing the bearings on a few dry runs goes. I'd say that has a lot to do with the amount/type of lubrication he used on assembly. I know when Erik and I put the final touches on mine these are some of the very questions I asked. But the more I think about it I highly doubt a few seconds (2) times would do any damage unless the bearings where bone dry.
Last edited by oscs; 11-25-2014 at 10:07 PM.
11-26-2014, 12:59 AM
#27
Yeah I hear you and not disagreeing with you. Just tying to give the guy a different perspective to make SURE something is messed up before pulling the motor completely. Checking the oil pump bypass spring to make sure its not broke or stuck bypassing oil etc... I don't care if its new, Ive seen new **** messsed up right out of the box! Making sure the pressed in oil galley plug is in place behind the front cover etc... I've seen a TON of little stuff like that etc... GL!
11-26-2014, 03:24 AM
#28
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The basic principals of bearing coating is correct as you have explained but you are wrong about pressure not separating the friction surfaces. The more load that is applied, the more pressure needed in order to maintain your pillow of oil between the two surfaces. This is basic stuff. As many motors as you've put together and your going to tell this guy 10psi hot idle is ok? Will it work? Sure becuase its under no load. Is it anywhere near desirable? Absolutely not. My freshly built boost built motor hot idles almost 20 psi more than this and you can believe my tolerances are loose. This is with 15W30.
Oil pressure is in the oil galleys not on the bearing surfaces in general as they are open to bleed off the oil,if you think about it the pressure feed for the crank then is on the opposit side of the load bearing surface and it gets pressure every revolution when the oil holes on the mains line up with the block oil holes
The 10psi per every 1000rpm is allso contradicting what you are saying about it being to low as its 10psi at lets say idle of 750prm,the cold start cranking compression that pushes on the assembly of lets say 200psi is 40 times greater then the oil pressure of 5psi at 500rpm and the oil is definetly going to get squshed out,pressure will not seperate the parts as its fed from the top to the main bearing surface that is not loaded
Yes your oil pressure is high because you have a good block that has the lifter bores tight and higer volume pump/thicker oil but mains/rods loose and that should point out to you that the pressure is related to the total volume of clerances of the parts in the motor and pump volume
Last edited by Ari G; 11-26-2014 at 06:30 AM.
11-26-2014, 07:55 AM
#29
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I hear you and there is always exceptions to the rule (especially with eriks motors) personally I just hate to see such low pressure and would be tearing stuff apart if mine did the same. As far as him not trashing the bearings on a few dry runs goes. I'd say that has a lot to do with the amount/type of lubrication he used on assembly. I know when Erik and I put the final touches on mine these are some of the very questions I asked. But the more I think about it I highly doubt a few seconds (2) times would do any damage unless the bearings where bone dry.
11-26-2014, 07:59 AM
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Yeah I hear you and not disagreeing with you. Just tying to give the guy a different perspective to make SURE something is messed up before pulling the motor completely. Checking the oil pump bypass spring to make sure its not broke or stuck bypassing oil etc... I don't care if its new, Ive seen new **** messsed up right out of the box! Making sure the pressed in oil galley plug is in place behind the front cover etc... I've seen a TON of little stuff like that etc... GL!
11-26-2014, 08:00 AM
#31
Yes its ok as long as it rises with rpm Oil pressure is in the oil galleys not on the bearing surfaces in general as they are open to bleed off the oil,if you think about it the pressure feed for the crank then is on the opposit side of the load bearing surface and it gets pressure every revolution when the oil holes on the mains line up with the block oil holes The 10psi per every 1000rpm is allso contradicting what you are saying about it being to low as its 10psi at lets say idle of 750prm,the cold start cranking compression that pushes on the assembly of lets say 200psi is 40 times greater then the oil pressure of 5psi at 500rpm and the oil is definetly going to get squshed out,pressure will not seperate the parts as its fed from the top to the main bearing surface that is not loaded Yes your oil pressure is high because you have a good block that has the lifter bores tight and higer volume pump/thicker oil but mains/rods loose and that should point out to you that the pressure is related to the total volume of clerances of the parts in the motor and pump volume
Last edited by oscs; 11-26-2014 at 10:24 AM.
11-26-2014, 08:03 AM
#32
Yeah I hear you and not disagreeing with you. Just tying to give the guy a different perspective to make SURE something is messed up before pulling the motor completely. Checking the oil pump bypass spring to make sure its not broke or stuck bypassing oil etc... I don't care if its new, Ive seen new **** messsed up right out of the box! Making sure the pressed in oil galley plug is in place behind the front cover etc... I've seen a TON of little stuff like that etc... GL!
11-26-2014, 10:10 AM
#33
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Well guys I appreciate all the help all the info has given me a better idea of what to look for. Imma gonna run the motor till I get it finished and then maybe slap a new oil pump in it. Go from the m295 to the 10296. And see what happens. And after that if problem still persist. Then I'll run it till I get my lq4 finished and then swap motors. And go with that.
11-26-2014, 10:19 AM
#34
Well guys I appreciate all the help all the info has given me a better idea of what to look for. Imma gonna run the motor till I get it finished and then maybe slap a new oil pump in it. Go from the m295 to the 10296. And see what happens. And after that if problem still persist. Then I'll run it till I get my lq4 finished and then swap motors. And go with that.
11-26-2014, 11:52 AM
#35
Again these are obvious things your pointing out. The only point your making is that yes your motor CAN start and idle on 10PSI. The question here is why is it only making 10PSI when it should be making 30. Also the relationship between 10psi of oil pressure per 1000RPM is directly related to load. In no way are your bearings under any significant load at idle. Again 10psi will keep your bearings coated at idle but to me indicates possible underlying issues. Just my .02 take it as you will
With that said, I agree with Ari. I've run M10295 on engines that should have had a 10296 or 10355 pump and they were just fine with 10-15psi at idle. That's enough to operate the lifters, which is really all that's needed at idle.
Regardless, Ari also addressed that the M295 is probably the reason for the low oil pressure, which I also agree with.
11-26-2014, 11:56 AM
#36
I think the point he is making is that gauge pressure is not the same as the pressure of the film on the bearing, so an increase in gauge pressure with an increase in RPM isn't necessarily indicitive of supporting more load. The eccentricity of the bearing has more influence of the oil film pressure than the gauge pressure. With that said, I agree with Ari. I've run M10295 on engines that should have had a 10296 or 10355 pump and they were just fine with 10-15psi at idle. That's enough to operate the lifters, which is really all that's needed at idle. Regardless, Ari also addressed that the M295 is probably the reason for the low oil pressure, which I also agree with.
I never meant to give the impression that pressure on the gauge and actual bearing surface oil pressure are the same, rather that with an increased load an increase in pressure is needed to maintain the pillow. Also I'm running a M295 on my boosted iron block with twice the hot idle pressure. As inspector12 stated, Everyone is entitled to their own opinion. At the very least this is bringing up some good info on the subject.
Last edited by oscs; 11-26-2014 at 12:12 PM.
11-27-2014, 12:01 AM
#38
Cool! Glad you verified this stuff and its one of the benefitts of putting stuff together yourself. Of course there is a ton to be said for experience doing it as well. I would jump right to the Melling 355 in the future. Although I hate Melling pumps due to the conversation I had with them but thats personal etc... But not a ton of options on that lol. GL! hopefully you eventually figure it out. Your issue turned into a decent tech topic LOL.
12-03-2014, 10:48 PM
#39
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ALRIGHT!!!!!! soo actually tearing down a complete 6.0L i bought about a month ago. and i think i may have solved my oil pressure issue not sure so someone chime in and tell me if you think this could be it! Cam retainer not installed. have a CEL for Cmp and have installed a new cam sensor and everything code still returns. i know its in time and its a brand new cam! i know now looking at this cam plate on this engine (6.0) i did not install anything that looked like it and it would explain my cam code and my oil pressure issue? im pretty sure it seals the oil galley does it not??
12-04-2014, 08:52 AM
#40
ALRIGHT!!!!!! soo actually tearing down a complete 6.0L i bought about a month ago. and i think i may have solved my oil pressure issue not sure so someone chime in and tell me if you think this could be it! Cam retainer not installed. have a CEL for Cmp and have installed a new cam sensor and everything code still returns. i know its in time and its a brand new cam! i know now looking at this cam plate on this engine (6.0) i did not install anything that looked like it and it would explain my cam code and my oil pressure issue? im pretty sure it seals the oil galley does it not??