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Catch Can ain't catchin' nothin' - why?
I installed an M7 Catch Can a couple of months ago. When I removed the intercooler (about 13K miles), there was virtually no oil in it; just a slight film around the intercooler 'necks'. I cleaned the intercooler and installed the Catch Can, per M7's instructions.
So now, 4K miles later, there's no oil in the Catch Can and I'm guessing the intercooler is still clean. What gives? Are there some cars that get a lot of build up in the intercooler/catch can and some not? If so, why :confused:. TIA |
According to George, proprietor of Mini-Madness, the amount of blowby that a catch-can will accumulate varies wildly by car - from drops to ounces per month.
A couple of issues: - Oil and pressure leakage around the valve stems into the head is extremely dependent on the individual engine and driver. Mileage, engine vintage, how often it has been abused, and the way you drive are major factors. Later engines - `05 and `06 cars seem to have very tight heads and little blowby. - Try putting some steel or copper 'wool' into the catch-can, to increase the surface area that the oil vapor has to flow through. Catch-cans will often filter very little oil out ot the PCV output unless they have plenty of surface area on which to condense the oil. The OCC on my `05 caught essentially nothing until I put some copper pot-scrubber fuzz in it - now it gets a dozen drops/month. Bottom line is that less oil blowby is better - it shows that you have tight, unworn, valve seals. You may have wasted $100, but at least you know that the head is in good shape. |
Originally Posted by OldRick
(Post 1218142)
- Try putting some steel or copper 'wool' into the catch-can, to increase the surface area that the oil vapor has to flow through. Catch-cans will often filter very little oil out ot the PCV output unless they have plenty of surface area on which to condense the oil. The OCC on my `05 caught essentially nothing until I put some copper pot-scrubber fuzz in it - now it gets a dozen drops/month. Another thing is to run a tube (plastic/heat tolerqant) inside the catch can on the inbound side that runs 1/2 to 3/4 of the way down into the can. This forces the inbound air to be introduced mid way into the can as opposed to accross from the outbound/exit hole. So the air has more can travel - flowing upwards THRU the steel wool to the outbound side. When I was experimenting with homemade OCC, I found this (along w/ the steel wool) to be more effective than just an empty OCC. I also drilled various holes on the tube sides to create more than one exit for the air. I attached the tubing simply by finding a diameter slightly larger than the OCC nipple nozzle and pushed/forced it in. I get about a tablespoon a month. |
Originally Posted by AntiqueCarNut
(Post 1218125)
I installed an M7 Catch Can a couple of months ago. When I removed the intercooler (about 13K miles), there was virtually no oil in it; just a slight film around the intercooler 'necks'. I cleaned the intercooler and installed the Catch Can, per M7's instructions.
So now, 4K miles later, there's no oil in the Catch Can and I'm guessing the intercooler is still clean. What gives? Are there some cars that get a lot of build up in the intercooler/catch can and some not? If so, why :confused:. TIA |
Thanks, everyone for the info :thumbsup:
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SInce there's water vapor in that engine blow-by, avoid steel wool. Try something that doesn't rust. It works just the same.
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Copper Brillo pad - available at most Home Depot and other stores.
Got mine at Smart & Final - a restaurant supply store here in CA. |
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