When i was putting my engine together, my dad thought it would help if i put a high pressure oil pump on. I didnt argue and we put it on. Now we have a rear main seal leak on my brand new engine, I was just wondering if the high pressure of the oil pump would make it blow by the gasket, or did i just mess up when putting the seal in? Just wondering, I just wanna drive my car, so if anyone could help thast would be great.

 

You messed up the seal.

 

I build all engines with a higher volume/ higher pressure pump. No problems out of any of them. It was either a bad seal or faulty installation.

 

theres no real need for such pumps on a stock engine, unless its really built

only need 7psi per 1k RPM

a stock design pump is more than adequate

i shake my head everytime i hear someone using a HV pump on a street engine, unless its a really built engine seeing a ton of RPM
and if so then it would need a deeper oil pan sump and other modifications


ppl think more and bigger is better but its not always so


everyone has their own opinions/lack of info/knowledge, but really you dont need an HV pump

good luck

 

I prefer the HV pump and have good reason for it. The standard oil pump just will not keep the pressure up in this climate and the loading that I sometimes have my engine under. I have the factory towing package, which gives an external oil cooler. I have a 7 quart Moroso pan, 2 quart filter, the oil cooler and I can still stress this engine enough to make the pressure drop with a HV oil pump(Oil just thins out too much). The BeCool radiator keeps it plenty cool on the coolant though. The oil temps one day were close to 275-300*(seared my fingers on the dipstick through the paper towl!!), pulled over and let it cool off, then drove on. I happened to get it so heat soaked that the 10w40 that was gurgling around in the pan only gave 10 PSI at idle, instead of the much more normal 40-50. I usually have 40 PSI even on a 90* day, without a load. The bearing clearances are actually a little tighter than I would have liked, but oh well.

The difference in HP taken to drive the oil pump is negligable anyway between a stock volume pump and a high volume. I mean, I can turn the HV up to 70 PSI of oil pressure when prelubing an engine with a 1/4" drill. Can't take too much power.

Just make sure you have a good deep pan, good oil drainback, and you will be fine.

PS-I spin my engine to 6,500 RPM!

 

Without getting into the HV versus standard oil pumps *nudge*

Are you sure it's really the rear mean seal or is it actually the oil pan gasket?

 

Good question? Don't typically see too many rear main failures compared to the pan gasket. Those 4 piece pan gaskets can be tricky. I use the single piece pan gaskets as they are AWESOME.


I haven't figured it out, I state a FACT and it turns into an debate(not just this thread, many of them).

 

Actually, you stated a preference.

HV pumps were the hot ticket back when oils were pretty lame. With modern synthetics (the "real" stuff, not the wannabes), the conditions you stated would not phase the lubricant.

Same story with larger capacity pans.

If you still think you've got "issues", an engine oil cooler will handle them and have none of the drawbacks of an HV pump or a pan sticking out where 3rd gens don't like them.

 

5/7- I do run synthetic(Vavoline Synpower), have an oil cooler and still have issues. Granted it is not a thirdgen and gets the crap beat out of it daily.

I did state a FACT not a PREFERENCE. I have not experienced ANY rear main seal failures and have used them on all my engine builds.

 

Synpower is a wannabe.

linkz, I'll have to agree that the HV pump is not part of your leakage problem. It won't do you much good as far as the engine is concerned, but it won't hurt anything, either.

As for what's leaking, you've gotten good advice so far. I've also seen intake manifold leaks that appeared to be rear main/oil pan leaks.

 

Don't forget the oil galley plugs and the camshaft plug on the back of the block, they can leak as well. Oil pressure sending unit provisions can also leak as well. There are 2, one to the driverside of the distributer on top of the engine and one by the oil filter.

If it means anything the Mobil 1 did the same thing, so I am back to synpower.

I am thinking of buying an oil-coolant heat exchanger like a boat has, in order to cool my oil better than the factory GM oil cooler.

 

you need AMSOIL, right 57?

linkz, try washing off the engine, then starting it up, about 2' up in the air, and poke around, make sure you can see it leak from somewhere... Hate to have to replace a seal that's very hard to get to, only to have to redo it. Maybe try that dye stuff? you know about that stuff?

 

I'd be more worried about why the temps are reaching 300*. There's too much friction in there somewhere.

 

Thanks for all of your input and debating. Really helpful. Ill narrow the leak down, and i hope its something easier to change then the rear main. I just assumed it was that because it was leaking straight from the midle of the flywheel, Im prolly gonna take it somehwere and have them narrow it down. I just wanna drive my car again. thankd for the input

 

3,500 RPM, 7,000-10,000 lbs(towing), 5,500 unloaded, uphill, 60-70 MPH you get the picture.

 

Don't for get about the 105+ texas day to help out with that.

 

A/C was blasting as well. The BeCool radiator is a monster and it was still running 215+ degrees. It has a HD fan clutch and 7 bladed clutch fan as well.

 

read this over carefully
IVE POSTED MOST OF THIS BEFORE BUT IT FITS HERE AS A SOURCE OF INFO FOR THE NEWER GUYS
[
ok lets look at a few things, pressure is the result of a resistance to flow , no matter how much oil is put out by the oil pump there is almost no pressure unless there is a resistance to that oil flow and the main resistance is from oil trying to flow through the bearing surface clearances and once the pumps output pressure exceeds the engines ability to accept the oilflow at the max pressure the oil return system/bypass spring allows the oil circles back through the pump ,now the amount of oil flow necessary to reach the furthest parts in the engine from the oil pump does not go up in direct relation to rpm, but it instead increases with rpm at a steadly increaseing rate that increases faster than the engine rpm due to centrifugal force draining the oil from the rods as they swing faster and faster since energy increases with the square of the velocity the rate of oil use goes up quite a bit faster due to the greatly increased (G-FORCES) pulling oil from the rod bearings over 5000rpm going to 8000rpm than the rate of oil flow increases from 2000 rpm to 5000rpm (the same 3000rpm spread) and remember the often stated (10 lbs per 1000rpm)needs to be measured at the furthest rod and main bearing from the pump not at the pump itself, next lets look at the oil flow itself, you have about 5-6 quarts in an average small block now the valve covers never get and hold more than about 1/3 to 2/3 of a quart each even at 8000 rpm (high speed photography by SMOKEY YUNICK doing stock car engine research with clear plastic valve covers prove that from what Ive read) theres about 1 quart in the lifter gallery at max and theres about 1 quart in the filter and in the oil passages in the block, that leaves at least 2 quarts in the pan at all times and for those that want to tell me about oil wrapped around the crankshaft at high rpms try squirting oil on a spinning surface doing even 2000rpm (yes thats right its thrown off as fast as it hits by centrifugal force, yes its possiable for the crankshaft WITHOUT A WINDAGE SCREEN to keep acting like a propeler and pulling oil around with it in the crank case but thats what the wrap around style milodon type windage screen is designed to stop)the only way to run out of oil is to start with less than 4 quarts or to plug the oil return passages in the lifter gallery with sludge or gasket material! now add a good windage tray and a crank scrapper and almost all the oil is returned to the sump as it enters the area of the spinning crankshaft! forming a more or less endless supply to the oil pump, BTW almost all pro teams now use DRY SUMP SYSTEMS WITH POSITIVE DISPLACEMENT GERATOR PUMPS that are 3,4,or 5 stage pumps each section of which has more voluum than a standard voluum oil pump because its been found total oil control is necessary at high rpms to keep bearings cool and lubed

NOW I POSTED THIS BEFORE BUT IT NEEDs REPEATING
ok look at it this way,what your trying to do here is keep an pressureized oil film on the surface of all the bearings to lube and cool them and have enough oil spraying from the rod and main bearing clearances to lube the cam and cylinder walls/rings. now a standard pump does a good job up to 5000rpm and 400 hp but above 6000rpm and 400hp the bearings are under more stress and need more oilflow to cool and because the pressure on the bearings is greater you need higher pressures to maintain that oilfilm.lets look at the flow verus pressure curve. [color:"red"] since oil is a liquid its non-compressable and flow will increase with rpm up to the point where the bypass circuit starts to re-route the excess flow at the point were the pressure exceeds the bypass spring pressure. but the voluum will be equal to the pumps sweep voluum times the rpm of the pump, since the high voluum pump has a sweep voluum 1.3-1.5 times the standard pump voluum it will push 1.3-1.5 times the voluum of oil up to the bypass cicuit cut in point,that means that since the engine bearings leakage rate increases faster as the rpms increase because the clearances don,t change but the bleed off rate does that the amount of oil and the pressure that it is under will increase faster and reach the bypass circuit pressure faster with the high voluum pump. the advantage here is that the metal parts MUST be floated on that oil film to keep the metal parts from touching/wearing and the more leakage points the oil flows by the less the voluum of oil thats available for each leakage point beyond it and as the oil heats up it becomes easier to push through the clearences.now as the rpms and cylinder preasures increase in your goal to add power the loads trying to squeeze that oil out of those clearances also increase. ALL mods that increase power either increase rpms,cylinder preasures or reduce friction or mechanical losses. there are many oil leakage points(100) in a standard chevy engine.
16 lifter to push rod points
16 pushrod to rocker arm points
32 lifter bores 16 x 2 ends
10 main bearing edges
9 cam bearing edges
16 rod bearing edges
2 distributor shaft leaks
1 distributor shaft to shim above the cam gear(some engines [/color] that have an oil pressure feed distributor shaft bearing.)
so the more oil voluum the better,(AS LONG AS ITS TOTALLY UNDER CONTROL ON BOTH THE PRESSURE AND RETURN/SCAVAGEING SIDES OF THE SYSTEMchevy did an excelent job in the design but as the stresses increase the cooling voluum of the extra oil available from the larger pump helps to prevent lubracation delivery failure, do you need a better pump below 5000rpm or 400hp (no) above that level the extra oil will definitely help possiable deficient oil flow and bearing cooling and a simple increase in pressure does not provide a big increase in voluum that may be necessary to keep that oil film in the correct places at the correct voluum at all times.the stock system was designed for a 265cid engine in a passenger car turning a max of about 6000 rpm but only haveing the stress of under 300hp transmitted to the bearings, Im sure the orriginal designers never thought that the sbc or bbc would someday be asked to on occasion hold up to 450-800hp and 6000-8000 rpm.nore did they forsee valvesprings that placed 500lbs and up loads on the lifters and the use of over 9 to 1 compression ratios in the original design so the oil voluums and pressures necessary to cool those valve springs and bearings at those stress levels were never taken into account for that either.

Continued (oil Pan/pump)
the oil pump can only pump as much oil as the engine clearances allow at the max pressure that the oil pump bye -pass circuit will allow, and no more. for your idea to be correct (which it could be under some conditions)the oil flow through the engine clearances would need to be so great that the pump turning at 3500rpm,7000rpm engine speed(remember the pump spins 1/2 the speed the crank does)and most likely pumping at max pressure could lower the oil level to the point that the pick-up becomes uncovered or a vortex as you call it forms and the pump starts sucking air.


now under hard acceleration it is very possiable for the pickup on ANY oil pump to to become uncovered in a oil pan that has less than 5qt capacity and with no oil control baffles as the oil rushes to the rear of the oil pan if the pick-up is located in mid pan or under hard brakeing if the pick-up is located at the rear of the pan on a non- oil baffle controlled pan.

I will grant you that it is possiable for ANY oil pump to pump a good amount of oil into the lifter gallery at high rpms IF THE OIL RETURN PASSAGES IN THE HEADS AND LIFTER GALLERY ARE BLOCKED, preventing its normal return to the crankcase

, but running a high volume oil pump will have little or nothing to do with how much oil is in the pan if the engines drain back holes are clear and your useing a milodon style windage screen. I have several times had that same complaint about lack of oil pressure under acceleration but it is caused by a non-baffled pan or the pickup mounted so close to the pan bottom that the pump cant get a good intake flow, if you carefully check youll find that on a dyno runs it seldom happens,because the oil is constantly removed by the windage screen is returned to the sump, most of the oil pumped into the system exits at the rod and main bearing clearances or at the cam bearings and from the lifter bores lower ends, its not the constant oil flow or lack of oil into the rocker arms that has the big effect on total oil flow as SMOKEY YUNICKS PHOTOGRAPIC RESEARCH PROVED YEARS AGO,its the oil flowing from the bearings and lifters and that oil flow is quickly returned to the sump by a windage screen scrapeing it off the spinning crank and rods as the spinning assembly passes over the windage screen. in effect most of the oil in an engine works like your timeing chain in that it constantly cycles top to botton and back never getting higher than the cam bearing lifter area.

[color:"red"] now what does quite frequently happen [/color] is that the guys installing a high volume oil pump just swap out the standard pump, reinstall the stock or simular pick-up and bolt on the pan with the pick-up in the stock possition on the oil pump. the stock pick-up is mounted about 3/8" off the pan bottom,the high volume pump is normally equiped with impeller gears about .3 inches longer than stock, the high volume pump body is that much lower in the pan, resultting in the pick-up being only about 1/8" from the pan bottom. the result is that on a normal chevy oil pump pick-up this leave a space of about 1/8" x 2.5" for oil to flow into the pump. at low rpms this works but as the rpms climb the pick-up that can,t get any oil to pump cavitates as it spins and fails to pump oil, result oil pressure drops untill rpms are lowered no matter how much oil is over the pick-up. simply checking to make sure that anout 1/2" of space is under the pick-up when the pan is installed cures that problem (a simple trick is to weld a 1/2" thick nut to the oil pump Pick-up base and test fitting the pan BEFORE WELDING THE PICK-UP TO THE PUMP BODY)

what it comes down too in every case that Ive looked into so far is a improperly positioned pick-up or a non- baffled oil pan without a windage screen or less than 5 qts of oil in the system, not a problem of all available oil being pumped into the lifter gallery and valve covers like some people would like you to think.

the MELLING COMPANY HAS THIS TO SAY

Most of the stock automobile engines are designed to operate from idle to 4500 RPM. The original volume and pressure oil pump will work fine in this type of application. As the demands on the engine increase so does the demands on the oiling system and pump.
The oil pump's most difficult task is to supply oil to the connecting rod bearing that is the farthest from the pump. To reach this bearing, the oil travels from three to four feet, turns numerous square corners thru small holes in the crankshaft to the rod bearing. The rod bearing doesn't help matters. It is traveling in a circle which means centrifugal force is pulling the oil out of the bearing.

A 350 Chevy has a 3.4811 stroke and a 2.111 rod journal. The outer edge of the journal travels 17.5311 every revolution. At 1000 RPM, the outer edge is traveling at 16.6 MPH and 74.7 MPH at 4500 RPM. If we take this engine to 6500 the outer edge is up to 107.9 and at 8500 it is 141.1 MPH. Now imagine driving a car around a curve at those speeds and you can feel the centrifugal force. Now imagine doing it around a circle with a 5.581, diameter.

The size of the gears or rotors determines the amount of oil a pump can move at any given RPM. Resistance to this movement creates the pressure. If a pump is not large enough to meet the demands of the engine, there will not be any pressure. Or if the demands of the engine are increased beyond the pumps capabilities there will be a loss of oil pressure. This is where high volume pumps come in; they take care of any increased demands of the engine.

Increases in the engine's oil requirements come from higher RPM, being able to rev faster, increased bearing clearances, remote oil cooler and/or filter and any combination of these. Most high volume pumps also have a increase in pressure to help get the oil out to the bearings faster.

That is what a high volume pump will do. Now let Is consider what it will not do.

It will not replace a rebuild in a worn-out engine. It may increase pressure but the engine is still worn-out.

It will not pump the oil pan dry. Both solid and hydraulic lifters have metering valves to limit flow of the oil to the top of the engine. If a pan is pumped dry, it is because the holes that drain oil back to the pan are plugged. If the high volume pump is also higher pressure, there will be a slight increase in flow to the top.

[/color] let me point out this chart





http://www.diabolicalperformance.com/clearances.html
heres other info,
http://www.babcox.com/editorial/ar/ar10180.htm

http://www.thirskauto.net/BearingPics.html

http://www.waynesgarage.com/docs/oil.htm

http://www.jimcookperformance.com/Te...s/TN%2023.html




http://www.cryoeng.com/images/Engine...itySecrets.htm

http://www.melling.com/engoil.html

http://members.aol.com/carleyware/library/engine2t.htm


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Crane suggests cutting a .030-inch-wide by .030-inch-deep slot in the lower band of the distributor housing to direct a spray of oil onto the camshaft and distributor gears. Use a Dremel tool to cut the slot into this distributor.

ITS just a tip for improving the oil flow to the distributor, BUT it HELPS a good deal with cam/distributor gear life so its a STANDARD MOD I always do!(keep in mind youll want the grouve location to spray oil into the gear teeth contact area , moving the distributor timing moves the oil spray area so the CAREFULLY CUT grouve in the block seems like a better IDEA