Engine drain plug magnet

Moto Guzzi V700, V7 Special, Ambassador, 850 GT, 850 GT California, Eldorado, and 850 California Police models

Created: 2014 March 24

Updated: 2014 April 29

I extracted this information from Kim Schick off of the old Yahoo! Loopframe_Guzzi news group (which has now moved to Groups.io). In Kim's own words...

Cow magnets are an excellent alternative. Much less $$ than the magnetic plugs that are available and they have increased magnetic attraction for collecting the metal filings, etc. If it's good enough to collect barbed wire in cow stomachs, it must be good enough for our Guzzi's!

Cut one to length and groove with a Dremel tool. Note: They are very hard and difficult to cut, but are the perfect diameter. Prior to using JB Weld Original, ensure fitment into the filler cap is acceptable. Clean the magnet and grooves to remove residual oil/etc. Fill cap and apply pressure to remove air. Allow to cure for 24 hours.

Have not had a failure 50,000+ miles, and that includes JB-ing the dipstick too. Found the stock dipstick on the cow magnet during an oil changed with no harm to internals...

My $0.02...

Thanks to Kim Schick for the additional information he e-mailed to me:

Cutting the magnet down also allows for you to use it in the transmission and rear drive...

Thanks to Kevin Kelly for sending me these photos and description of how he added a very strong magnet to drain plug. In Kevin's own words:

With no oil filter on our loop frame machines, I have always been concerned about metal fillings in the oil. The screen may take out the really big ones but little else. The small magnet they sell that goes in the drain plug is so small and so far from where the oil is circulating I rarely see very much on it. The last oil I bought was over USD $6.00 per quart so do not like changing the oil all the time from what other say to do. So what to do?

One day while at the farm store I noticed some Cow Magnets ¹⁄₂ inch wide by 3 inch long and they were very strong, priced 3 for USD $12.00. The next time I brought along a spare drain plug and looked at the situation. It looked easy, there is a cavity inside our stock and replacement drain plugs that the magnet would fit right into, along with some JB Weld, I had a real magnetic drain plug.

The magnets are very smooth so I used my grinding wheel and ground 6 small groves on the side of the magnet where it will fit in the drain plug. On the drain plug I got my dremel tool and carefully cut some shallow groves inside of it. Cleaned the whole thing with contact cleaner. I then mixed up about ¹⁄₂ teaspoon of JB Weld and put some in the drain plug hole and around the magnet and inserted the two together. Made sure we had good contact with some coming out the top of the plug and excess was easily wiped away. I then set the drain plug with the magnet pointing straight up and made sure it was straight by checking it at two different 90° angles. When doing this keep at least one foot away from any metal as it has a strong attraction and can tilt to it. I usually check it a couple of more times in the next hour to adjust and be sure it is still straight. Does not have to be perfect but close. 24 hours later it was done. Total investment USD $5.00.

It does displace about 1 tablespoon of oil so no issue there. If for some rare reason the magnet would come out, I did check to see where it would go and it lodged being held in place by the oil dipstick and the return pipe from the breather, perfect.

I have used these in my three loops for the last 3 years and was amazed how much magnetic material is attached to it. And when you do change your oil you can see all the material that would have been floating around in your oil. You can feel the magnet with the dip stick, and want to be sure it is straight when hand screwing it in place. I believe every loop should have something like this in place to remove that material that otherwise is going around and around in our oil and lodging in our crankshaft sludge traps, and other places destroying our beloved Loop frame.