351 C oil pump

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boilermaster

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I have replaced many an oil pump, but have never rebuilt one, even with my many years at the Ford Dealership.

I am wanting to shim the spring on a new standard volume pump and wish to know a few things first : should it matter which side of the cup that a 1/8'' or 3/16'' washer goes ? and once the cotter pin is removed

how heavy a press is the cup ?.

Have already specked the rest of my new pump and it checks OK.

Thinking the cup has to be a press fit so it won't bleed oil past it.

Would rather remove the cup and inspect and clean it's bore, but also thinking one could also just measure and press the cup in the same amount of the spacer washer.

Don't want to have to waste the cup in the new pump just to remove it because T don't know where I could get another cup without buying a rebuild kit.

No guesses please !

Boilermaster

 

MeZapU

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If anything is wrong with the oil pump on a Cleveland I would say that the bypass circuit in the oil pump is not large enough. Even my old engine and a stock volume pump, I would have almost 80psi at idle when cold (5w30 oil) and when warm it would go down to 40psi at idle. I made the high volume pump mistake years ago and broke several distributor gear roll pins and went through several bronze gears. It's just not needed. If you have loose bearing clearances then that may change things. High pressure pumps were a crutch when not addressing other high rpm oiling issues. High pressure is almost as bad as high volume when to comes to distributor gear wear.

Unless your engine is going to live its entire life at the dragstrip, I highly suggest you research other oiling modifications(restrictors and lifter bushings) and stick with the stock oil pump as it was designed. It is overall a better choice.

 

boilermaster

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If anything is wrong with the oil pump on a Cleveland I would say that the bypass circuit in the oil pump is not large enough. Even my old engine and a stock volume pump, I would have almost 80psi at idle when cold (5w30 oil) and when warm it would go down to 40psi at idle. I made the high volume pump mistake years ago and broke several distributor gear roll pins and went through several bronze gears. It's just not needed. If you have loose bearing clearances then that may change things. High pressure pumps were a crutch when not addressing other high rpm oiling issues. High pressure is almost as bad as high volume when to comes to distributor gear wear.

Unless your engine is going to live its entire life at the dragstrip, I highly suggest you research other oiling modifications(restrictors and lifter bushings) and stick with the stock oil pump as it was designed. It is overall a better choice.
Well MeZapU,

Perhaps that's exactly what I needed to hear as I have fully grooved

Main Bearings and the restrictors for the cam bearings (new cam bearings) and new lifters that are .001'' Oversize with metering to the pushrods.

also just picked up an upgraded oil pan.

Boilermaster

 

barnett468

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Yes the hole in the oil galley plug is a good idea, however, .030 is actually way to big . . Even an .020" hole will spew MASSIVE amounts of oil on it so .020' is WAY more than big enough.

another hole the same size in the other oil galley plug will oil the bejesus out of the timing chain, and gears, and thrust washer on the cam.

I wouldn't run fully grooved bearings in a high revving engine because it reduces the size of the oil wedge formed under the crank . . It's common practice to only use partially grooved bearings for that purpose.

If you plan to beat on it, I would use Tri Metal bearings.

If the front bearing gets installed too deep in the journal, it can expose a lot of an oil passage which will allow oil to gush from it . . The factory depth for this bearing is only .003" from the front of the block.

I would NOT rely on the press fit of the cup to to hold it in place . . It is far safer to use a flat washer.

Remove the bypass piston and make absolutely certain that it moves freely the length of the hole and if you even think it does not, use a small ball hone to enlarge the hole slightly.

The oil hole in the block that the oil pump mounts up to is often smaller than the hole in the pump so i drill the passage out to the size that matches the pump . . you can also just taper/bevel the entrance to the hole . . of curse thousands of engines run fine without a lot of these mods but it never hurts anything by to doing them and i just look at it as basically free insurance to do them.

i driil the cam restrictors out to around .090"

you can also install a plug with a .120 hole in it in the front crank journal oil passage that leads to the right side lifter galley most puople use a solid plug but i prefer to see that particular journal still get some additional oil.

 
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MeZapU

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The distributor shaft below the gear is already pressure fed oil on a 351c, so it is overkill to drill any extra oiling holes in my opinion. If you are not running lifter bushings, I would be extremely hesitant to doing this mod as you are bleeding off oil pressure at the point furthest away from the pump. Enough to make a difference? Maybe. But every little bit helps when the rpms start getting high. Just run a std volume oil pump and you should be fine. High pressure/volume oil pumps are the main factors to premature distributor gear wear.

 
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barnett468

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Yes, the gear is pressure fed, however, there have been many cam gear failures for whatever reason, and many of those have been fixed by adding a hole in the galley plug, so imo, if one is going to rev their engine high, or has a bronze cam gear or a high volume oil pump etc, it is better to be safe than sorry and I have never seen a case where adding more oil to a gear or bearing created damage.

As far as a .020" hole creating any tangible reduction in oil pressure. I can guarantee unequivocally that it will not irregardless of the condition of the rest of the system . . Pressure inside a hydraulic system will be exactly the same everywhere unless there are some anomalies, it simply has no other choice than to be the same, therefore, it makes no difference whether the hole is in the beginning of the system or at the end.

If you calculate the actual area of a .020" hole and the area of the .001" space between the lifter and the bore, or compare it to the amount of oil lost between both ends of the push rod etc, you will see that it is not a lot . . Also, as I mentioned, a .020" hole is way bigger than needed in this area so if one is concerned about using a hole that size, they can simply move down to a smaller one like .015" . . One really has to see how much fluid comes out a hole this size with 40 psi of pressure to fully appreciate it.

Also, as pressure goes up, volume goes down, so the higher the rpm, the less oil that will flow thru the hole.

If you look closely inside the lifter bore at 30 seconds into the video, you can see just how much oil gushes out of a tiny .020" hole when using just a tiny hand pump


.

 
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basstrix

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Barnett468, will you please qualify the statement "as pressure goes up, volume goes down, so the higher the rpm, the less oil that will flow thru the hole."? This goes against first principles of fluid dynamic theory.

 

barnett468

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Barnett468, will you please qualify the statement "as pressure goes up, volume goes down, so the higher the rpm, the less oil that will flow thru the hole."? This goes against first principles of fluid dynamic theory.
Yeah, that's a bit vague to say the least and thanks for noticing so I can modify it.

As the pressure in the oil galley increases, the velocity of the oil exiting the hole will increase, however, the volume of oil exiting from the hole would be exactly the same as the volume of oil entering the galley if there were no other leak sources in the galley.

.

 
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boilermaster

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Well.

I had previously set the front cam bearing @ 0.003'' good there.

Someone had already massaged the oil pump passage at the block

and just to be super careful I mocked up the distributor and seated it as to not leave the distributor driveshaft loose when torqueing the oil pump bolts.

I had also manually ran a couple of quarts of oil thru the pump before bolting it up.

will remove distributor and prime her up once the pan is on and lifters are in, and again before start up.

Looks like I can get back into the garage tomorrow.

Boilermaster

 

barnett468

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I had also manually ran a couple of quarts of oil thru the pump before bolting it up.
I use Joe Gibbs break in oil.

 
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Having worked in a NASCAR engine shop many years ago I agree with many of the statements about the high volume or high pressure oil pumps. The major failures we would see would be broken valve springs causing broke valves and then you know the results. The other thing you would see when doing a tear down was that the bearings had began to wash out. Not caused by rpm, stress or bad bearings but caused by oil pressure and flow. You do need good pressure for lubrication and cooling of the bearings at high rpm but that also results in early bearing failure. DON'T blame the bearings.

An engine with a wet lifter gallery needs to have attention paid to the clearance between lifters and bores. You can get the lifters plated with hard chrome if you cannot find oversize ones but you will need to centerless grind them to final size to true them back up and get rid of the feathering that plating gives.

Pontiac engines were notorious for having oversize lifter bores that lets too much oil leak out and starve the bearings.

I got out of the shop before the cleveland engines made their way in so did not get to learn anything there.

For a street stock engine I would not use a high pressure or high volume pump.

David

 
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It was just so much easier for us to hone the bores to a size and plate and grind the lifters since grinder was there. If you have to ream and hone the bores then install bushings and hone again that is a lot of work.

I guess it depends on what you have to work with.

David

 

barnett468

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the oil pressure should 60 psi in most high perf street engines . . the prob is that some of these pumps are set by melling for 47 psi and you just wont know until its in and the engine is in so i install 60 psi springs when i feel they are needed and when they are avail . . it is impossible for 60 psi of oil pressure to damage the gears unless they are simply made wrong or are chinese . . also high oll pressure will not damage bearings . . . . . te dc wed frmed by the rtating crnk ndd ca is actly fr hher in prre t

 
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MeZapU

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From my experiences...

Installing lifter bushings is quite an investment financially and in labor. It is almost certainly the single best oiling improvement you can do to a Cleveland. Bushings along with restrictors pretty much fixes every oiling concern. If you are having bearing issues after these mods, then there are other problems with the build that were likely not identified/addressed during mock-up/assembly. In all honesty, these mods are not even needed if the engine is built around a modest street combination that will not see past 6000 rpm's. Only if you are planning a significant assault on horsepower would these modifications be warranted.

These modifications are not about "mores law" but about controlling what is already there. More oil and more pressure ware essentially an easy crutch back in the day before these racing oiling concerns were properly understood and addressed. Internet forums propagate misinformation, rumors, hearsay, racer fixes and redneck bravado while very frequently the real solutions are ignored as they don't have the same level of charisma. The real fixes are often not cheap or easy. These modifications do hot have any prospects of making a single horsepower. $500 and many hours spent on these mods is not what most people want to hear when a $50 oil pump seems like a sufficient solution. I don't care how much oil you spray on a bronze distributor gear, it will wear just as fast regardless. The gear degrades due to material fatigue and not specifically wear due to lack of lubrication. Bronze is inherently a metal that has a higher lubricity than a cast iron or steel gear. That in itself would require less lubrication than normal. I would find brass slivers shaved off the gear in my oil filter inspections telling me the real story.

Groves in the bearings are always from foreign matter and no fault of the oiling system.

http://www.7173mustangs.com/thread-new-351c-build?page=2

 

basstrix

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From my experiences...

Installing lifter bushings is quite an investment financially and in labor. It is almost certainly the single best oiling improvement you can do to a Cleveland. Bushings along with restrictors pretty much fixes every oiling concern. If you are having bearing issues after these mods, then there are other problems with the build that were likely not identified/addressed during mock-up/assembly. In all honesty, these mods are not even needed if the engine is built around a modest street combination that will not see past 6000 rpm's. Only if you are planning a significant assault on horsepower would these modifications be warranted.

These modifications are not about "mores law" but about controlling what is already there. More oil and more pressure ware essentially an easy crutch back in the day before these racing oiling concerns were properly understood and addressed. Internet forums propagate misinformation, rumors, hearsay, racer fixes and redneck bravado while very frequently the real solutions are ignored as they don't have the same level of charisma. The real fixes are often not cheap or easy. These modifications do hot have any prospects of making a single horsepower. $500 and many hours spent on these mods is not what most people want to hear when a $50 oil pump seems like a sufficient solution. I don't care how much oil you spray on a bronze distributor gear, it will wear just as fast regardless. The gear degrades due to material fatigue and not specifically wear due to lack of lubrication. Bronze is inherently a metal that has a higher lubricity than a cast iron or steel gear. That in itself would require less lubrication than normal. I would find brass slivers shaved off the gear in my oil filter inspections telling me the real story.

Groves in the bearings are always from foreign matter and no fault of the oiling system.

http://www.7173mustangs.com/thread-new-351c-build?page=2
Well put!

 

barnett468

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distributor and cam gear wear and damage is caused by many things which include poor quality material, incorrect mesh, incorrect clearance, poor finish, insufficient oil, and poor quality oil etc, however, it is never caused by increasing the amount of oil to them . . there is absolutely no harm whatsoever in increasing the amount of oil to the gears or the timing chain etc and it is something that some very big name engine builders that have a long history of building reliable quality engines have done for years and continue to do to this day, but there is harm in having too little oil go to them, its that simple, therefore as i mentioned drilling this hole is added insurance which costs nothing to do, and only takes maybe 10 minutes from start to finish . . you are free to not do this yourself but its wrong to imply that it definitely wont help or may do harm by decreasing oil pressure.

Although these gears did not have any excessive wear problems in stock engines, one thing people overlook is the fact that they are not using stock parts when they rebuild them . . a comp cam or lunati cam is not a stock cam and may very well be made from lower quality material than the factory one and/or the finish on the gears may not be as good . . the same goes for distributor gears on after market distributors etc and i know for a fact that msd has a lot of their parts made in china although i dont know every part they have made there, however i do know that they use one of the highest quality bronze gears available, but unfortunately, that means absolutely nothing if the placement of the gear on the shaft is incorrect or the cam gear is crap etc.

there are MANY stories on the net about broken distributor gears and cam gears, especially regarding comp cams for some reason, yet i have never broken, damaged, or worn out either of these gears in 40 years of driving and building engines, and i have in fact used high volume pumps in several apps AND bronze distributor gears, maybe i was just lucky and didn't get crappy parts, i just dont know

this being said, i now inspect ever distributor and cam gear closely and if the edges of either are razor sharp which they have been on a few, i dull them slightly, and if the finish on the face of the bronze distributor gears is not smooth, i will run it over a wire wheel . . i have known people that were have premature wear on bronze distributor gears, so the finally took the exact same brand of gear and ran it over a wire wheel but changed nothing else and never had another prob with it . . they then began doing the same thing on all the bronze gears they used in engines and never had another problem so there is obviously something to doing this on the bronze gears at least.

i also know someone that had a similar prob with bronze gears, and all they did was drill a hole in the galley plug and install a new gear from the same mfg and they now have around 20,000 miles on it . . these cars did not come with bronze gears and in this case, increasing the amount of oil to it did fix the problem however odd that may sound to some.

im not saying that increasing oil to the gears is a cure all for bad gears, however, my point remains, it can not possibly do any harm but it may help, so why not do it?

 
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basstrix

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I seem to have come across more distributor gear probs with comp cams also. I wonder if they're doing something different with their cam gear?

 

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