Engine cleaning...

Mel0

New member
I'm trying to pinpoint an oil leak(s) but I need to clean all the gunk off to even see. Thing is I can park it in my garage for three days or even longer and I never see any oil on the floor but when I stop driving and park it I can always smell something burning. What is reccomended to "degrease" the engine? Can I just use brake cleaner or will it hurt anything? Thanks!
 
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curious about this as well. I always thought it was oil dripping from my valve covers onto the exhaust manifold but the valve covers were replaced last winter. I've lived with the faint smell of burning oil but want to get to root cause. In the process of replacing a cv axle today I wiped off all the shiny oil on the undercarriage with a rag and simple green will check in a couple days to see if any has resurfaced..
 
dont use brake cleaner as it is a harsh chemical and will eat away at vacuum lines, and wires and plastics... get something like a engine degreaser say like gunk or penzoil or steam... yeah any of those type of products... soak the motor in couple of cans of that stuff (fallowing their instructions) and then clean off, this should give you a good cleaning, now there might be some areas that still need more attention -if they are on say like the block or metal brackets you might be ok with using some brake or parts cleaner to address those specific areas, but make sure to rinse those off with water asap.

you might want to do two treat ments of the engine degreaser depending on how dirty the motor is.
 
run to autozone or advanced auto and ask them for an engine cleaner. all the cleaners should do the same thing really, getting rid of grease and oil on metal. using brake cleaner is definitely not the right product. I personally agree with the approach of covering the alternator with a plastic bag and other sensors/parts with electrical wires, as well as the fuse box. (others dont care and wash them down with water). then spray the engine down with the cleaner and wash it out with your garden hose or at the local DIY carwash (power-wash if you choose this option).

if you want to get more advanced, you can buy colored dye's that you put on various parts of the engine. if oil leaks on the dye you'll see the color of the dye.
 
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I just looked in to this myself cause of a coolant smell on a 4runner I was thinking about purchasing (and got, and coolant smell is gone - must have been a spill). Still need to do it so I can track how significant my vc gasket leak is.

Anyway, from what I've gathered (and from doing it on other vehicles), don't do it on a hot engine. I've heard that stuff may be removed easier if it's warm, but with winter temps here I can't imagine spraying a 200+ degree engine with 40 degree water would be advised.

Plastic shopping bags over alternator, fuse box, battery, air box/MAF any other electronic related item that you've added. Lightly mist the engine bay from a distance to get everything wet. Spray engine degreaser everywhere and let it go to work (you can use the can stuff, some use simple green diluted, etc). Wait several minutes and rinse in the same manner you wet it down.

I've also used electric tooth brushes in the past as a follow up. You can get them extremely cheap and they do wonders for smaller/tighter spaces.

If your car starts immediately after, cool - get in and drive. If it refuses to start it's easiest to just wait and not panic.

Only difference I've read about on here that I never worried about in the past doing this to Subarus, is not focusing too hard on the spark plug area. You could probably put a little vaseline around there to prevent anything seeping in but that's why low pressure from a distance is recommended.

I've always used an old tshirt to blot up the chemically water residue should any remain, but if you're not going for show car look and just want to get to the bottom of something I don't think it's as important. You can follow up with whatever shiny stuff you want if it's safe for rubber. Let us know how it goes
 
A clean engine may or may not help you pinpoint the leak. You said the valve cover gaskets were replaced last winter so it's deffinitly possible some of the bolts on the valve cover have come loose (this is fairly common). Check them and make sure they are torqued down properly. Give the valve cover a good 'ol reach around on the back side and you may feel some freah oil its common to collect their if its leaking. it will feel new not old and gunky. Chances are this is where it's coming from if you smell burning oil because it will eventually drip onto the exhaust manifold.
 
I had/have a similar issue, tightened my valve covers, cleaned everything, no drips where I park but still a faint oil smell, the oil has been full for months with no sign of excessive burn, Trans is full too... I'm starting to lean towards a pcv issue, maybe there's a small crack in a vaccume line or something weird, but no other signs of any serious problems building besides some odor...

To answer your question, garden hose, gunk, blow dryer, couple of hours to sit.
 
I just go to the quarter car wash and power wash it. I don't cover anything and haven't had any problems, and I do it fairly regularly (I like a clean engine). I've done this to every car I've owned in the last 30+ years (gave my age away). With a good power wash you really don't need degreasers, though some car washes have an 'engine cleaner' or 'tire cleaner' setting - the tire cleaner works well - if you want to add some degreaser. Just be ready to get wet. If you really want to hit everything you have to get down on the ground and spray up under the engine.
 

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