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Re: It's in, running and has too high oil pressure???
[Re: dennismopar73]
#702606
05/20/10 12:03 PM
05/20/10 12:03 PM
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Joined: Oct 2004
Posts: 8,165
Left Coast
BobR
master
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master
Joined: Oct 2004
Posts: 8,165
Left Coast
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Quote:
WHAT ????
YOU HAVE THAT BACKWARDS
30 is 30
10w 30 10w 40
5w30
it is a 30 w until the temp starts falling
below the 32^
then it stats to act like thinner
wieght for easier starts in winter
i used to spec out oil for trucking companies
desil oil have certain properties to help in sludge/ breakdown additives and soot control
 
You may want to do a little research before calling someone else wrong. And if you used to "spec" diesel oil why don't know how to spell "diesel". Actually, Multi-weight oils (such as 10W-30) are a new invention made possible by adding polymers to oil
At cold temperatures, the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up, the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C, the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot. Maybe we just aren't looking at this the same way but I absolutely know that in the instance of a 20W-50 oil the base stock IS 20W and the polymer additives give it 50W properties.
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Re: It's in, running and has too high oil pressure???
[Re: BobR]
#702607
05/20/10 12:24 PM
05/20/10 12:24 PM
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Joined: Nov 2009
Posts: 2,177
ill
dennismopar73
top fuel
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top fuel
Joined: Nov 2009
Posts: 2,177
ill
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ok we just had three valvoline reps in our store rep meeting some of what you say is almost correct but if say 20 is the starting oil in 20 w 50 no which is ashland oil, makers of several oil some independant oil they cannt say so the makers must be wrong then. heating of oil will make oil pressure seam to get lower here the result , everthing expandes as motor gets warm metal expandes you agree ?? so does rod main clearances cam etc so there is where most of that pressue goes away action reaction thing wounder how 0w 20 works mmm 0 wieght in my race car thatll work  this is a good discussion i like it as for research me and my brother spect oil out so it does come from first hand knowlege  as for spelling not in school and my typing skills not the best fat fingered and need new keyboard sorry for that i will stay after school and write it on the blackboard 100 x hahaha 
Last edited by dennismopar73; 05/20/10 12:29 PM.
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Re: It's in, running and has too high oil pressure???
[Re: MR_P_BODY]
#702608
05/20/10 12:29 PM
05/20/10 12:29 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Quote:
Quote:
so how is it you guys are missing this BEFORE you drop the engine in the car?
i always prime engines while on the stand so there's no surprises afterward.
So Dram... what would you expect to see for a pressure
while priming and what size drill motor(or what
ever you use).... I know on my stuff I usually see 70
for a HV pump on a smallblock with a std. spring (not hi pressure) and wider racing type bearing clearances, i normally see 65-70 lbs. while priming with a 1/2 HP 1/2" drill at 2400 rpm, which would be equivilent to 4800 rpm engine speed.
as a rule the smaller 3/8 drills are 1/4-1/3 hp and are too weak to turn the pump at full rpm, so the pressure reading could vary quite a bit using one of those.
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Re: It's in, running and has too high oil pressure???
#702609
05/20/10 12:42 PM
05/20/10 12:42 PM
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Joined: Feb 2009
Posts: 1,532
off the grid
340B5
pro stock
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pro stock
Joined: Feb 2009
Posts: 1,532
off the grid
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Dis be whut de espurts say;  Polymers expand and contract to both ends of the spec. Wt. @ 70* is somewhere in the middle. At least thats whut they teld me in automotive skool anyhoo.
Yeah, it's got a smallblock.
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Re: It's in, running ,has too high oil pressure**UPDATE
[Re: dc426]
#702614
05/21/10 01:33 AM
05/21/10 01:33 AM
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Joined: Dec 2006
Posts: 3,667
Arizona
Chris'sBarracuda
master
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master
Joined: Dec 2006
Posts: 3,667
Arizona
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Quote:
Thanks for all the input guys.
DRAM, First off We primed it on the stand with a gauge attached. It showed 75 LBS. constant with a high torque drill. Don't know what else to expect
Last night I drained the Rotella and this morning tried a 5w-30. As the motor warmed up the pressure fell to about 75 at idle and was around 85 at 3500-4000. It looked as if it would continue to fall as the motor got hotter. I had the temp up to 160. Of course that's not necessarily the oil temp but it seems to prove as the motor gets warmer the oil pressure is falling into place.
The old oil pump stated at 65 regardless if it was hot or cold.
I would never pull an engine or the pan because my oil pressure was 5-10 pounds too high.. 
You can get real old really fast stressing about nothing.. 
Run it and have fun with it. Stop working on it.. 
Chris...
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Re: It's in, running and has too high oil pressure???
[Re: Sixpak]
#702615
05/21/10 10:31 AM
05/21/10 10:31 AM
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Joined: Oct 2007
Posts: 4,206
New York
polyspheric
master
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master
Joined: Oct 2007
Posts: 4,206
New York
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You may not see actual spark scatter, but it doesn't help.
pump does accumulate most of the pressure rest is generated by mains
No true: the pump is only refreshing the leakage from the bearings. It provides only a very small proportion of the actual dynamic pressure, most of it is RPM × viscosity × journal OD.
Boffin Emeritus
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Re: It's in, running and has too high oil pressure???
[Re: polyspheric]
#702616
05/21/10 10:44 AM
05/21/10 10:44 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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IMHO, a small hole drilled through from the pump exterior to intersect the relief piston bore just ahead of the piston at full retraction will add to relief volume (and reduce overpressure), it just won't be recirculated. This is probably not true with all pumps, but my subject pump has a .420" relief piston (.138" area), but the relief port is only 11/32" diameter (.093" area), and only bypasses 67% of the possible volume. A single 7/32" hole to the exterior will only open when the piston is fully retracted and will not affect normal operation. This brings the total bypass dump area up to .130", almost the same area as the valve itself. No, I haven't tried it yet. Anyone see anything that's going to bite me?
To be honest I think that would work well... I dont
foresee any issue because it would only open that
port at or right near max open... which in case would
help dump the aerated oil
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Re: It's in, running and has too high oil pressure??? *DELETED*
[Re: MR_P_BODY]
#702617
05/21/10 11:24 AM
05/21/10 11:24 AM
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Joined: Oct 2007
Posts: 4,206
New York
polyspheric
master
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master
Joined: Oct 2007
Posts: 4,206
New York
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Post deleted by polyspheric
Boffin Emeritus
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Re: It's in, running and has too high oil pressure???
[Re: polyspheric]
#702618
05/21/10 11:29 AM
05/21/10 11:29 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Thanks, I was afraid I was tripping over something obvious!
My subject pump has the piston just barely sealing the passage at rest, so enlarging the existing hole can only be done to the rear in any event. A diametric increase is not a good idea since it captures the piston from cocking upward under pressure.
Some pistons may be possible to just reduce the length to allow it to reach full unmask position (or modify the retainer). Check the spring to make sure it doesn't bottom out 1st, etc.
I am assuming this pump you are working with is a
in pan pump so you can dump the oil
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Re: It's in, running ,has too high oil pressure**UPDATE
[Re: dc426]
#702619
05/24/10 10:45 PM
05/24/10 10:45 PM
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Joined: Jan 2005
Posts: 1,466
malvern, ohio
3ddart
pro stock
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pro stock
Joined: Jan 2005
Posts: 1,466
malvern, ohio
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well, having posted here before, thought i'd update my progress, none!!! spent most of today switching out the sb oil pump i put in at the rebuild a month ago, it had over 100 lbs pressure and blew oil past the oilboss gasket onto the headers causing me to be black flagged. this happened above 4500 rpms. at idle it was 80 lbs and the 1 i replaced from last yr was 65lbs going down the track. 1 i put in today did exactly the same as the previous 1, reved it to about 4000 and saw smoke coming off the headers and sure enough it blew past the gasket again! now my ? is could i have done something on assembly to create this problem? pumps both came straight from melling (contingency reward) and block was cleaned with soap water and brake cleaner, honed by machine shop, and recleaned, crank was polished only and motor was reassembled. i have never had any problems like this before and thats why i'm reaching out to those of you in the know. always put some oil in the pump and assembled my motors before this and pressure was 50 to 60 at hot idle and 70 to 80 going down the track. i called melling about the 1st pump and they said they're not aware of any issues with these pumps. i called today but it was after hrs so i'll see what they say tomorrow. but in the meantime any suggestions on something i could have messed up on assembly? as always thanks in advance and thanks tom!! dave
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Re: It's in, running ,has too high oil pressure**UPDATE
[Re: 3ddart]
#702620
05/24/10 11:09 PM
05/24/10 11:09 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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I really dont think its you... sounds like they have a by-pass spring issue.... you put on 2 different pumps only to have the same issue... I would say that takes you out of the problem... you could cut the by-pass spring down some.... or take the spring out of your old pump(from the original pump that worked) clean it and install it in your new pump.... and make sure the little piston/cup moves freely
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Re: It's in, running ,has too high oil pressure**UPDATE
[Re: MR_P_BODY]
#702621
05/24/10 11:24 PM
05/24/10 11:24 PM
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Joined: Apr 2005
Posts: 1,880
USA
Ron Silva
top fuel
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top fuel
Joined: Apr 2005
Posts: 1,880
USA
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I think you said you changed the bearings? I think you literally have a good tight engine and you have to go to a standad volume Pump. You have too little flow required and the PP bypass cannot handle it. Basic physics. Most race engines in the past used big bearing clearances and big if not huge rod side clearances and needed the high volume PP. You probably have stacked all your clearances to the small side. I sure hope you did not do all that work and put another HV pump in there. Sorry if you did.
So your bearing clearances are nice and tight and possibly the Rod side clearances. Main Rod and rod side clearances affect oil pressure the most. Well rod side clearances could affect pressure if they were way too tight. Be sure and check them.
Last edited by dragrcr97; 05/24/10 11:27 PM.
SRT DEMON ONE SEAT
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Re: It's in, running ,has too high oil pressure**UPDATE
[Re: MR_P_BODY]
#702623
05/25/10 09:02 AM
05/25/10 09:02 AM
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Joined: Jan 2007
Posts: 3,695
nc
emarine01
master
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master
Joined: Jan 2007
Posts: 3,695
nc
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Quote:
I really dont think its you... sounds like they have
a by-pass spring issue.... you put on 2 different pumps
only to have the same issue... I would say that takes
you out of the problem... you could cut the by-pass
spring down some.... or take the spring out of your
old pump(from the original pump that worked) clean
it and install it in your new pump.... and make sure
the little piston/cup moves freely
 We had the same problem with HV melling in our small block, we swaped springs from a old pump and have 64 psi just about all the time, when the oil gets real hot it falls to 45 @ idle and goes right back to 64 with any rpm increase, good luck , pullin the pan was a PITA but solved the problem
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Re: It's in, running ,has too high oil pressure**UPDATE
[Re: 3ddart]
#702625
05/25/10 10:29 PM
05/25/10 10:29 PM
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Joined: Nov 2004
Posts: 892
USA
krw71ragtop
super stock
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super stock
Joined: Nov 2004
Posts: 892
USA
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Look what 100 psi did to the filter on the left.  I consider myself lucky I cought it. 416" sb
Last edited by krw71ragtop; 05/25/10 10:36 PM.
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