oil drain plugs larger than 1/2-20???

[chuzie]

Went to swap the oil drain plugs in my 351w pan for magnetic variants. I ASSUMED they were 1/2-20 but were too small.

Considering the potential age of this pan (30+ years), I am willing to bet it has been stripped and tapped at some point. If not, can anyone tell me if there was a 351w application that would have had dual sumps and plugs larger than 1/2-20?

Thx.

 

[Broncobowsher]

None that I know of. But I believe they sell the repair plugs in 1X oversize. And if you strip that out there is a 2X oversize, and it you keep butchering it a 3X oversize is also available. If you have stripped out the 3X drain plug you need to find a new oil pan and someone else to change your oil.

 

[chuzie]

I just wanted magnetic plugs. Guess I will just slap a button RE magnet on the existing plugs.

Thx for info.

 

[anoblefox]

I use a rare earth round flat magnet on the bottom of the pan directly next to the drain plug. Just before I remove the drain plug I first remove the magnet. The theory is the oil draining out will tend to make any magnetic (iron/steel) particles come out also. Then I return the magnet back to the bottom of the pan before I screw in the drain plug.

 

[Steve83]

I just wanted magnetic plugs.

Better a magnetic FILTER. Drop the magnet down the throat of your next new filter. Those little buttons are cheap in bulk.

Guess I will just slap a button RE magnet on the existing plugs.

I wouldn't, but if I did, I'd counterbore the drain plug tip, and glue the magnet in-place thoroughly. Glue won't inhibit the magnetic field, but a smooth coating of glue will make it easier to remove any filings it collects.

Just before I remove the drain plug I first remove the magnet. The theory is the oil draining out will tend to make any magnetic (iron/steel) particles come out also. Then I return the magnet back to the bottom of the pan before I screw in the drain plug.

That's not what's happening. Because the pan is the skin of an enclosed Iron (steel) chamber, it acts like a shield, preventing the magnetic field from reaching inside. But it's not 100% effective, and over time, that part of the pan becomes magnetized. So even though some filings will tend to collect there, removing the magnet for a few seconds doesn't release them. You'd have to flip the magnet (to reverse its field) and leave it like that long enough for it to kill the pan's field (possibly minutes; possibly hours; possibly days, depending on the permanent magnet's strength & the composition of the pan).

 

[EricLar80]

That's not what's happening. Because the pan is the skin of an enclosed Iron (steel) chamber, it acts like a shield, preventing the magnetic field from reaching inside. But it's not 100% effective, and over time, that part of the pan becomes magnetized. So even though some filings will tend to collect there, removing the magnet for a few seconds doesn't release them. You'd have to flip the magnet (to reverse its field) and leave it like that long enough for it to kill the pan's field (possibly minutes; possibly hours; possibly days, depending on the permanent magnet's strength & the composition of the pan).

Not sure that I agree. I get where you are going with it - a Faraday cage of sorts. But a compass still works inside of a Faraday cage, so magnetism is not affected in the same manner as electricity. It will work with electromagnetism, which is an AC generated field and different than a static magnetic field. I do agree that the magnets strength would be attenuated, however.

Easy way to test it out - put some iron shavings in a soup can with the lid still attached and a magnet on the outside. Close the top & shake the can. Remove top and see if anything stuck to where the magnet is.

Eric

 

[Steve83]

Easy way to test it out - put some iron shavings in a soup can with the lid still attached and a magnet on the outside. Close the top & shake the can. Remove top and see if anything stuck to where the magnet is.

I agree that would be a valid experiment, but only if 1) the magnet is left in one position on the can for about the same time as a typical oil-change interval, 2) the can's steel is largely the same blend & temper as the oil pan's (something that would be more difficult to ascertain), and 3) the filings are the same as those that might be found in typical engine oil (again: hard to confirm unless they're removed from actual engine oil withOUT the use of a magnet).

 

[EricLar80]

Nah. Campbell's cream of mushroom and some filings from some scrap cast iron would test the thought. Just make sure you wash out the can first. :-*

If you really want to blow your mind, drop a rare earth magnet through a copper pipe.

 

[ransil]

If the over sized plugs don't work, check Time sert for an insert repair.

http://www.timesert.com/

 

[707Bronk]

Nah. Campbell's cream of mushroom and some filings from some scrap cast iron would test the thought. Just make sure you wash out the can first. :-*

If you really want to blow your mind, drop a rare earth magnet through a copper pipe.

It works with Aluminum pipe too!