That model was rare. Ive only seen one. Found it on line.
Motor Guard By-Pass Filter
- Thread starter Turbo67
- Start date
My apologies for not responding sooner, apparently I am not getting email notifications. I sent in an oil sample back in November after setting up a bench test for a few days of filtering. I did not understand the results, so today, 5-29-25, I called Blackstone Labs and explained that I was interested in soot particulate. To have them perform a soot test, I have to add that to the comments section and add $10 to the total. I just changed the oil in my Diesel, so I am once again doing the bench test and I will send them a sample of that oil before running it through the bypass filter and a sample I run for a few days to replicate drive time on this oil change. The picture is of my "bench" setup, running at 37 psi and 175 deg F. And per a recommendation, I am using Amazon "Boardwalk" paper. It measures 4-3/8 tall, it is advertised at 4.5 tall, and its approximately 4-1/2 diameter. 500 2 ply sheets.
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The Motor Guard factory elements are 4 1/4 diameter and 4 1/2 tall. I believe the white ones are a tightly wound 2 ply. 4 3/8 tall is fine. I believe thats a compressed air filter with 1/4 inch pipe ports. The lube oil filter had 1/8 inch pipe ports with no orifice and no coating. I use 1000 sheet 1 ply. Unroll it to 4 1/4. Great Value 1000 from Walmart.
How do you heat the oil to 175f ? Cool bench set up btw, I also use 4 1/2" 500 Hojas de 2 Capas in my Motor Guard.
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The pumping action heats the oil. It took a couple of hours to stabilize at 175F, rising from ambient of 85F.How do you heat the oil to 175f ? Cool bench set up btw, I also use 4 1/2" 500 Hojas de 2 Capas in my Motor Guard.
I always thought these filters needed a center tube like a Frantz. The Frantz needs a center tube that fits the tp core. They depend on oil pressure to push the core down against the core seal. The Australian Jackmaster Classic has no center tube. The Gulf Coast junior has a center tube but its only purpose is to pull out the used tp. Its about 1 3/8 inch. With the top loaders you manually push the new roll down against the core seal and put on the lid. All the Motor Guard needs with the shorter 1000 sheet is a washer at the bottom or top with the filters that push up against the seal. Older Motor Guards. If the shorter paper is a problem you can always use a spacer. The Gulf Coast junior is out of production. Not sure you can still get the Australian Jackmaster Classic. My personal favorites.
Just to keep you guys in the loop, I bench filtered the next sample for about 120 hours and sent the unfiltered and filtered samples to Blackstone Labs today. I had decent printing of the Amazon Boardwalk Toilet Paper Roll both top and bottom post filtering.
In order for me to evaluate my modifications to the M100D Motorguard Air Filter to use it as a By-Pass Oil Filter, I set up a bench test you can see in earlier posts. I took a sample of oil with about 3600 miles on it from my 87 300D Mercedes, set that sample aside, marked it and then proceeded to filter the remaining 6 to 7 quarts of oil for 116 hours to "replicate" driving time as if the oil would have been filter if this setup was installed on the vehicle.
The confusing thing here is that the post filtering test "shows" more soot than before the 116 hours of filtering. Soot was .8% Vs .3%. I called Blackstone, they are confused as well and actually re-ran the tests, with the same results. Obviously the first thought is that I mixed up the samples and put the wrong labels on them. I do not believe that to be the case. Has anyone else sent off similar oil samples for testing to evaluate these filters? I worked diligently to make sure the Amazon Boardwalk roll was tight and checked the imprinting on the roll after the 116 hours and there is definitely printing from the top and bottom of the M100D onto the wet roll.
The confusing thing here is that the post filtering test "shows" more soot than before the 116 hours of filtering. Soot was .8% Vs .3%. I called Blackstone, they are confused as well and actually re-ran the tests, with the same results. Obviously the first thought is that I mixed up the samples and put the wrong labels on them. I do not believe that to be the case. Has anyone else sent off similar oil samples for testing to evaluate these filters? I worked diligently to make sure the Amazon Boardwalk roll was tight and checked the imprinting on the roll after the 116 hours and there is definitely printing from the top and bottom of the M100D onto the wet roll.
If the results are correct, the only thing it could be is that the filter on the vehicle works better than the bench set up?
All of this oil came from my crankcase. What I did was drain my oil after running it for 3600 miles. I then poured it into a clean poly bucket and set up the 116 hour filtering test. I took a sample of the drained oil just before I started the test and then another sample at the end of the test. Both samples then went to Blackstone for analysis.