compressed air in draining oil

**PatT** · June 16th, 2009 07:41 PM

GHOSTHUNTER- I`l probably take your advice on just starting and warming up the car prior to draining oil, thanks!

SORRY for my POOR advice ghosthunter...I think i`ll refrain or just stop giving advice on "tech" stuff as i`m sure experts like you can come to the rescue. I`l just ask questions instead.
patrick

**boy_tino** · June 16th, 2009 10:42 PM

ok gumamit ng air compressor for change oil kung ang hanging nito kung may filter ang labasan ng hangin at syempre kung in good condition pa rin ang filter ng air compressor.

pero pag walang filter sigurado ang binubugang mula sa labasan nito ay may moisture na kapag nagamit mo ito ng walang filter ay puede rin magkaroon ng moist or magka tubig sa loob ng makina mo

**ghosthunter** · June 16th, 2009 11:42 PM

Originally Posted by boy_tino

ok gumamit ng air compressor for change oil kung ang hanging nito kung may filter ang labasan ng hangin at syempre kung in good condition pa rin ang filter ng air compressor.

pero pag walang filter sigurado ang binubugang mula sa labasan nito ay may moisture na kapag nagamit mo ito ng walang filter ay puede rin magkaroon ng moist or magka tubig sa loob ng makina mo

This is only good IF you know 100% of the current condition of your air compressor, generally applicable if you have your own home workshop. But in most service stations where half a dozen guys would be working around cars and where the air compressor is just running on automatic all day long with maybe a weekly or bi-monthly check if it's working fine, I would rather play it safe and assume for the worst.

**jick.cejoco** · June 18th, 2009 12:46 AM

Originally Posted by sboogie

is using compressed air when draining the engine oil ok?

every time i do oil change the gas station always use compressed air to push out used oil from the engine.

i've been doing this to my 3 vehicles for a long time now.

just wondering if there are bad effects when doing this.

sboogie,
this idea is not genius. it is idiotic! the compressed air in most shops are set to 120 psi and your lubrication system is max at 80 psi setting on the relief valve. in some cars as the toyota cressida with 5MGE or 7MGE engines are set to 15 psi at the relief valve. applying pressure to the crankcase will may cause the oil seals to turn outward and cause to oil to leak from them, also, the old and maybe cracked valve cover gaskets will develop new leaks. both the main seals (front main and rear main), the camshaft seal/s and the pan gaskets might develop new leaks. the crankcase was never designed to handle 120 psi. to make the stale oil drain faster, warm the engine up by running it to make the oil thinner (thanks Pat) and to agitate or "stir the oil" to make the sludge and light solids float and go with the stale oil out to the drain catch pan. the oil contains dispersants to keep the sludge afloat but sludge settles if the engine had been at rest for a duration of time.
jick
instructor
guam community college

**arnarn** · June 18th, 2009 02:17 AM

*TS,

How long have you been doing this? may napapansin na po ba kayong bad effects? kakatapos ko lang kasi magpachangeoil kay raymond sarol. ginamitan din nya ng comrpessed air.

**marg** · June 18th, 2009 08:08 AM

No bad effects, we do this to our Toyota during every oil change. It now has 350,000 km mileage and still going strong.

**valvura** · June 18th, 2009 10:06 AM

stock knowledge ko lang ito guys. IMO, the compressed air pressure from hose nozzle would be less once ipasok sa engine block 'coz of the area where the air will flow will be bigger. in practice, hindi naman sinasara totally yung top & drain caps for the pressure to accumulate. also, droplets of water in oil is negligible kasi it'll just evaporate since the boiling point of oil is higher that that of water.

**sboogie** · June 18th, 2009 11:01 AM

jick,

i think you forgot that the oil filter and drain plug is not already taken off

so the so much pressure is not that much anymore

but still thanks for the info about how much psi of the air compressor has

**rusem** · June 18th, 2009 11:26 AM

imho, using compressed air blown inside the engine is not advisable. you see there is compressed air and there is compressed DRY air. compressing air can increase the air's capability to hold moisture. if anyone from you is from manufacturing and your process utilize compressed air, most probably its compressed dry air or CDA. the air is subjected to a drying process using an air dryer to remove or reduce the moisture content of air base on your manufacturing process' dewpoint requirement. i used to be from the car manufacturing industry and there's a reason why they use CDA on all assembly processes. especially during painting and engine assembly... it doesn't matter if the compressor from the shop / gas stations uses filter. it can't help any bit, even moisture separators won't help... bottom line is this is one of the causes oil contamination... so if you're not sure if blowing compressed wet air inside your engine does neither good nor bad to your engine, why just don't do it at all to save you from your worries...