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Clattering and no pressure after oil change


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Back feed oil under pressure through the system using an oil gallery.........common on expensive engines that sit......aircraft, race cars, ect. Like the one I used on my 1917 that sat for 80 years. I wrote about it a few months ago here. Similar to a power bleeder for a brake system flush. I use an old Freon tank with a shrader valve to provide an air fill. Look at the photo below. Common tool used in restoration shops and engine builders.

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Edited by edinmass (see edit history)
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An alternative to removing the distributor and using a powerful drill motor to turn the oil pump before starting the engine.

 

R r, it took a week for the oil to drain out?  Using axle grease rather than 30-weight motor oil?

 

Just some thoughts,

NTX5467

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Just fill the pan with the correct amount of oil, purge the system with the pressure pot, and you can actually fire the car up while pumping the oil backwards, just be sure to close the valve as soon as it fires up to prevent back flow into the tank. 

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1 minute ago, NTX5467 said:

The only "valve" would be in the oil filter to bypass oil when the flow is greater than what the filter can tolerate.


Some oil filters have one way check valves in them.......probably only post 1980 engines.........just a guess, as I am  a pre war guy.

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Perhaps not in the oil filter per se, as many filters now have a silicone anti-drainback flapper valve in them.  The pressure relief valve in either in the oil pump or, in the case of the spin-on-oil filter Chevy engines, the housing the filter screws onto.  When you look at the filter prior to installation, if you can see "rubber" just belot the ojuter ring of holes in the mounting plate, that's the anti-drainback valve, usually.

 

The pressure relief valve is there to keep from blowing uo the oil filter when higher rpms out more flow into the system than the filter media can flow.  Or the combination of higher rpms and cold, thicker oil.

 

Just to clarify,

NTX5467

 

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On hydraulic-lifter engines, sometimes an extended drain period will allow air to get into the oil galleys, which may not fully purge/escape when the oil filter floods the system again.  Earlier 1970s Chevy 454s had such an issue, even on a normal oil change.  Noisy lifters that would not quieten down quickly.  The factory fix was to put a .020" hole in the two screw-in, front oil galley plugs for the hydraulic lifter galleys.  The holes let the air out and also provided some additional lube to the upper timing gear and timing chain.  Initially, a TSB was issued and the particular galley plugs were later put in as normal production items.

 

Not sure if this might address your more vintage engine or not, but it might give you an idea of what might be happening.

 

Hopefully, you'll not need to disassemble the oil pump to pack it with petroleum jelly (or similar) to get the oil pump to work again.

 

Just some thoughts,

NTX5467

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We still don't know what the car is. It is posted in post war Buick, but frankly that doesn't narrow it down near enough.

 

In the absence of a pressure pot, get out the manual and look over the oiling system diagram, and see if there is a plug, sending unit, oil filter port, or anything that would allow you to pour some oil down in to the oil galleries from the pressure side in such a way that the oil would flow down into the pump. Thicker is better but probably anything would work.

 

Fill the new oil filter with oil, too. If it's a spin on, you might spill a little. C'est la vie.

 

If none of that works, and the oil pump is external to the engine, you could take it off. Or, take the cover off if the whole pump isn't easily removable. Pack the pump with Vaseline or light grease.

 

If that won't work, you are probably pulling the pan. If the car is prone to losing prime at oil changes (as some are at high mileage), it is probably time to rebuild or replace the pump while you have the pan off.

 

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Moral of the story: Change the oil more frequently if having 'clean' oil in the engine is a concern.  Letting it drain for an extended period risks draining the pump, losing prime and a dry re-start.  I also pre-fill my oil filters (as much as practical on horizontally mounted ones) to minimize the time it takes the system to build pressure.

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25 minutes ago, EmTee said:

Moral of the story: Change the oil more frequently if having 'clean' oil in the engine is a concern.  Letting it drain for an extended period risks draining the pump, losing prime and a dry re-start.  I also pre-fill my oil filters (as much as practical on horizontally mounted ones) to minimize the time it takes the system to build pressure.

Good advise.  Some people pull the plug on a hot engine and let it drain overnight to get all of the old oil out.  But most engines retain up to a quart in the galleys.   Pull the plug on a cold engine and replace when a tiny stream or drip, fill and start.

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On 12/31/2020 at 12:36 AM, Bloo said:

If none of that works, and the oil pump is external to the engine, you could take it off. Or, take the cover off if the whole pump isn't easily removable. Pack the pump with Vaseline

Right out of the Buick Shop Manual on a 455! Pack with Vaseline to prime pump. There is a long way between that oil pickup screen and the pump in the timing cover.

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A long time ago, when premium multi-grade motor oil was about $1.00/qt, I decided that to get all of the old oil out of the pan (as on most pans, the drain plug is slightly above the bottom of the oil pan), that after the main draining was almost done, I'd then pour an extra quart of new oil into the engine, to flush out that last bit of used oil.  A small investment in a complete oil change, I thought.  Then, when the last strings of oil are almost done, the drain plug would go back in and the normal amount of new oil would be added.  On vertical-mount oil filters, I'd also fill them and let the air bubbles settle out before I'd install it.

 

As current oils now cost well more than $1.00/qt and are of much better quality, I might not do that extra quart flush any more.  But the filters get pre-filled, still.

 

Just some thoughts,

NTX5467

Edited by NTX5467 (see edit history)
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On 1/1/2021 at 10:50 PM, NTX5467 said:

A long time ago, when premium multi-grade motor oil was about $1.00/qt, I decided that to get all of the old oil out of the pan (as on most pans, the drain plug is slightly above the bottom of the oil pan), that after the main draining was almost done, I'd then pour an extra quart of new oil into the engine, to flush out that last bit of used oil.  A small investment in a complete oil change, I thought.  Then, when the last strings of oil are almost done, the drain plug would go back in and the normal amount of new oil would be added.  On vertical-mount oil filters, I'd also fill them and let the air bubbles settle out before I'd install it.

 

As current oils now cost well more than $1.00/qt and are of much better quality, I might not do that extra quart flush any more.  But the filters get pre-filled, still.

 

Just some thoughts,

NTX5467

 

I also always pre-fill the filter prior to install during an oil change-

helps minimize a "DRY" start-up.

 

Sometimes if doing an oil change on a car which has really dirty oil, or has not been run in an extended time, I'll top-off, or add a quart of ATF and run it until well warm3ed up prior to draining and fresh refill

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