I have an oil leak, 99% sure it's the rear main seal. I've tried the liquid Bar's stop leak to no effect. SO - If the oil filter is bypassed or the element is removed - to NOT catch anything or get plugged up - can the powdery stop leak sold in the clear plastic tube (copper color, very fine particles), used for RADIATORS be mixed, in small amounts, to a quart of oil and then added to the engine? I'm unable to just stop and do the repair - don't have any alternative & have to use this leaking sob daily. I know it sounds a bit crazy, but if it doesn't get caught up in the filter, would it have a chance of lodging in the leak without engine problems? The powder is super fine, but I don't know the chem properties, clotting factors, etc. I'm not a formally trained mech, but have worked on every vehicle I've owned (150+) as well as friends, etc. Also, have an engineering degree (25 yrs ago) but have never used it for employment. Please give this some thought- let me know what you think
My car has 150000 miles.
My car has an automatic transmission.
I can’t really give you a positive yes or no answer as to whether stop-leak products will cure the problem. From experience however, I have seen them work for a time, I have seen them not work at all, and I have seen them do more harm than good in the short-to-medium term. By that I mean, I have seen leaks subside only to get even worse after a time. Was it due to a stop-leak type product ? Possibly. The material in those stop-leak products will migrate their way to the leak and possibly plug it for a time. What can happen over time however, is that same medium winds up moving or dislodging, and acts almost like grit. In a case like the rear main seal for example, the spinning crankshaft will spin that grit around the seal and possibly open up the leak even more than when you started. Incidents like this over the years even keeps me from recommending high-mileage oils as well. They contain ingredients that cause seals and gaskets to swell to "reduce oil leaks and oil consumption". Well swelling these seals increases the friction they now experience and in the same manner, temporarily slow leaks and consumption, only to have it get even worse down the road. I may not be speaking from science, but from 30+ years of experience.
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