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Discussion Starter #1
So I dont know if I should post this in Dyno section or here....but im choosing here because it seems to get more traffic.

So here goes, I have an oil pressure problem. Im running a little 461 bb chevy with a standard volume melling oil pump and a dooley 10 quart. When cruising im only running about 45lbs of pressure at 3000 rpm's. When I stand on it almost instantly I lose oil pressure until I let up. It drops to around 5lbs maybe less if I decided to keep my foot in it. I just pulled the motor, pulled the pan checked clearance to p/u and all is well. Nothing is blocking the p/u......basically nothing I can see. Im running 20w50. Ive tried three different weights before pulling the motor so thats not it.........The only conclusion i can come to is the pump:)bulb......Any suggestions as to what I should do? Im thinking of spending the money on a nice high volume....What to do?????????? Suggestions please, yuma next weekend is coming quick!! PLEASE HELP:)hand
 

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do you have enough clearance on the pick up, to the bottom of the pan? should be about a 1/4 inch space, less than that can cause the pump to cavitate. oops missed the fact you checked that, are you running a remote filter? any chance the lines are mixed up?
 

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Discussion Starter #5
I have about 3/8 of an inch of clearance from the p/u to the bottom of the pan. No remote oil filter directly on the block and I have 9quarts in the pan 1 in the filter.
 

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pull out 2 quarts. 9 is too much
Now im going to play dumb and ask, why would this cause a loss? Im trying to remember but I think I tried this.....maybe.....im just frustrated at this point and cant think. Spent my whole summer getting this thing on the water and everything went as planned except this
 

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Now im going to play dumb and ask, why would this cause a loss? Im trying to remember but I think I tried this.....maybe.....im just frustrated at this point and cant think. Spent my whole summer getting this thing on the water and everything went as planned except this
Oil hitting the crank causing windage foaming the oil. Most 10 quart pans only work with around 7 quarts. I had the same problem in two different 10quart pans. When you accelerate there is too much oil in the back of the motor and it gets ugly, as you can see by the oil pressure. 7 quarts in the pan is plenty. I even had this problem on the dyno we ended up with 6.5 quarts in a static situation. You could probably get away with 6 when it is in the boat.
 
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Oil hitting the crank causing windage foaming the oil. Most 10 quart pans only work with around 7 quarts. I had the same problem in two different 10quart pans. When you accelerate there is too much oil in the back of the motor and it gets ugly, as you can see by the oil pressure. 7 quarts in the pan is plenty. I even had this problem on the dyno we ended up with 6.5 quarts in a static situation. You could probably get away with 6 when it is in the boat.
I have seen this happen before as well and it could likely be your problem. I run 7 quarts total in a 10 quart pan.
 

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Discussion Starter #10
What about the cruising oil pressure, that doesnt seem low? So I have also heard of clearancing a pump to increase oil pressure a little?......Would it be wise to buy a new pump along with trying the less oil to try an avoid pulling this thing back out? The bad part is I wont be able to test before yuma...long ways to drive to still have an issue....
 

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I run a mellings HV77 pump and they have always worked well for me. They are cheap and if you have the time I would do it. along with dropping the oil level
 

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Discussion Starter #13
I run a mellings HV77 pump and they have always worked well for me. They are cheap and if you have the time I would do it. along with dropping the oil level
I believe thats the high volume? Mine isnt.....No time like the present to put another one in and it is a lot cheaper than what the other option could be:)st
 

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So I dont know if I should post this in Dyno section or here....but im choosing here because it seems to get more traffic.

So here goes, I have an oil pressure problem. Im running a little 461 bb chevy with a standard volume melling oil pump and a dooley 10 quart. When cruising im only running about 45lbs of pressure at 3000 rpm's. When I stand on it almost instantly I lose oil pressure until I let up. It drops to around 5lbs maybe less if I decided to keep my foot in it. I just pulled the motor, pulled the pan checked clearance to p/u and all is well. Nothing is blocking the p/u......basically nothing I can see. Im running 20w50. Ive tried three different weights before pulling the motor so thats not it.........The only conclusion i can come to is the pump:)bulb......Any suggestions as to what I should do? Im thinking of spending the money on a nice high volume....What to do?????????? Suggestions please, yuma next weekend is coming quick!! PLEASE HELP:)hand
This has been discussed a few times in the past, try doing a search. I remember something about the oil filter adapter can cause the problem you describe, a bypass not installed correctly or the indexing of the adapter to the block. Before you pull the engine pull the filter and remove and inspect or just change the adapter. Chevy guys will know more about this than I do as I'm a Ford guy.
 

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Discussion Starter #15
are you running a electric oil pressure guage or a mechanical? If electric, go buy a cheapy mech one and see what it says.
Just purchased a mecahnical the other day to double check the electric. That will definately be happening.
 

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Discussion Starter #16
This has been discussed a few times in the past, try doing a search. I remember something about the oil filter adapter can cause the problem you describe, a bypass not installed correctly or the indexing of the adapter to the block. Before you pull the engine pull the filter and remove and inspect or just change the adapter. Chevy guys will know more about this than I do as I'm a Ford guy.
This was also a question in my mind, I have heard of this happening. Motor is already out and pan is already off. So I will adress all of these suggestions before going back in.........I dont know what I would do without these forums!!!:)devil You guys are saviors!!(sp)
 

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While you have things apart make sure you use a quality filter. I use Baldwins but Wix, Purolator etc should serve you well. I have had 2 Frams fail, thats why I don't use them anymore.
 

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I use the HV melling and 20/50 and have never had any problems. I would get the new pump. Summit will have it here by Friday. Call now. I would try lowering the oil level as well and see if that is it. I have always run 10 in mine too with no problem but I have a windage tray. Good ideas here though. Check and see if there is any teflon tape on the sender as well that could be causing some greif. If you don't have a mech guage to check with, I have mine that I use for these types of problems.

Cy
 

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Discussion Starter #19
I use the HV melling and 20/50 and have never had any problems. I would get the new pump. Summit will have it here by Friday. Call now. I would try lowering the oil level as well and see if that is it. I have always run 10 in mine too with no problem but I have a windage tray. Good ideas here though. Check and see if there is any teflon tape on the sender as well that could be causing some greif. If you don't have a mech guage to check with, I have mine that I use for these types of problems.

Cy
I will be ordering the pump this morning. Mitch has never had an issue with 10 quarts either but I will definatley try this along with another pump. I had the teflon tape grief when I first fired the motor. I do have a mechanical but thank you for offering yours up! My pan has the windage tray as well, this is why it stumps me. but all I can do is try these great suggestions and cross my fingers....Thanks again guys!

Travis
 

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while you have the pan off check how many qts it takes to fill it.

also do you have an evacuation system of any kind? like from valve covers to
headers. I have seen this cause the symtoms your decribing.
 
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