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Oil through heater vents

Latech15

Well Known Member
So I recently changed the oil on my rv6 with a o-360. I started to find oil in the belly where there wasn?t oil before. It isn?t much, a half a quart every few hours.

I pretty much determined that it is leaking around the oil filter as everything below and behind it is oily.

I used my heater this week and noticed oil on the heater vent and the floor under it. I can?t seem to figure out how it is getting oil into the heater tube/vent area.

Anybody seen that or have any ideas?
 
Had oil leak -- defective filter

Recently --after short flights, had oil puddling under belly after oil change --- took awhile but traced it to a defective crimp on the oil filter body ----

Ron
 
I pretty much determined that it is leaking around the oil filter as everything below and behind it is oily.

Filters and oil are too cheap - that's an immediate oil change before further flight to fix it. Like right now. A bad crimp on the filter is total oil loss in less than a minute and an off-field landing.
 
] A bad crimp on the filter is total oil loss in less than a minute and an off-field landing.
So the filter (spin on I assume) is defective? :eek: Never seen that. Agree if that let loose.... You don't have to change the oil just the filter and replace the oil that was in the filter as required.

Please report this to the manufacture. It could be a whole batch of bad filters.
 
Changed oil. Found nothing wrong with the oil filter. I?m still getting the leak. After about an hour of flying I will have a few drops on the exit opening under the pipes and out the piano hinge on the passenger side corner.

It is t using an appreciable amount of oil so it would normally not be an issue, but it is getting blown I?m towards the firewall and into the heater vent opening so I can?t use the cabin heat.

I cleaned the engine well and ran it for a while and can?t seem to fine the source. Very aggravating.
 
Dipstick tube gasket is a common place to leak like that; it goes down the case and drips off a corner in the airstream. See if you have oil above/fwd of the dipstick gasket; if no then possibly it. Also the mag seal on the right side is about the level of the filter.
 
So I recently changed the oil on my rv6 with a o-360. I started to find oil in the belly where there wasn’t oil before. It isn’t much, a half a quart every few hours.

I pretty much determined that it is leaking around the oil filter as everything below and behind it is oily.

I used my heater this week and noticed oil on the heater vent and the floor under it. I can’t seem to figure out how it is getting oil into the heater tube/vent area.

Anybody seen that or have any ideas?

Check for loose bolts/nuts on the filter housing. I suspect this area if often neglected when re-tightening bolts after the first few hours on the engine. Also check for loose vernatherm and oil temp sensor if they are not saftied.
 
The reason that I suspected it was the oil filter was because it had a few drops of oil on the underside of it. After the oil change I am not finding oil there. There is oil towards the front of the engine on the drivers side, but that?s not where it is coming out the bottom. With all of the air flowing through there I can?t really come up with a good place to start. I?m afraid it is getting picked up and deposited everywhere in the stream of air.
 
The reason that I suspected it was the oil filter was because it had a few drops of oil on the underside of it. After the oil change I am not finding oil there. There is oil towards the front of the engine on the drivers side, but that?s not where it is coming out the bottom. With all of the air flowing through there I can?t really come up with a good place to start. I?m afraid it is getting picked up and deposited everywhere in the stream of air.

Clean engine thoroughly. Fly for an hour and use baby powder to identify the oil traces.

Larry
 
Baby powder?? Just blow it on the engine and it will stick to the oil I assume? That?s a new one for me but it sounds like it just might work.
 
Baby powder?? Just blow it on the engine and it will stick to the oil I assume? That’s a new one for me but it sounds like it just might work.

Yes, if the engine was cleaned first, it will stick very well to the oil and poorly on everything else. Need to shoot a little air to get the talc off everything that it has a bit of surface tension to, but not absorbed, like the oil. Also, it will typically change color when absorbed into the oil, unles you put on too much.

Larry
 
This is very interesting to me because I've had almost the exact same thing happen recently. My engine has always been bone dry and recently I've noticed oil streaks on the belly. I'd clean them off and they'd return and it seemed in a greater volume. So, I pulled the cowl for an oil change and some other work, and found oil collecting on top of the fuel pump and dripping onto everything below. The farthest up I could find a drop of oil was right below the oil filter mounting surface, so I put a wrench on all the bolts (which were tight anyway), changed the oil and filter and cleaned the engine up. Run up was normal and the engine was dry.

I had suspicions about the vernatherm and the oil temp sensor, but the drops I saw were above them...I'm going to run the engine and keep a hawk eye on things, but this has me wondering about the oil filter now.
 
Hoses

Check all your hoses carefully. I had same problem and it took me 10 flites and several flying hours to finally locate a small crack in the crankcase vent hose leading to my oil separator. It would mist out and end up flowing out the cowl and covering the belly. A little Oil makes a BIG mess.
 
I did a little digging yesterday and found the breather tube hose to be very loose and without a hose clamp where it attaches to the back of the engine. I read where a clogged breather could lead to a front main seal leak. I need to go back and check the rest of that breather hose. It very possibly could have gotten clogged which led to the blowout at the connection point.

I obviously have a leak up at the front main seal (camshaft seal) there is oil on the starter, alternator, and up inside the hub behind the prop.

My guess, since I am seeing two different oils on the belly, some black and burned and some brown and cleaner, that the breather tube leak is probably the black, and probably what was getting into my heater vent, and the brown oil is from the front main seal.

My question is if the hose being lose on the breather could result in a lower vacuum and thereby increasing the pressure in the engine leading to the front seal leaks???
 
I can?t seem to figure out how it is getting oil into the heater tube/vent area.

Anybody seen that or have any ideas?

The heater vent valve is open to the engine bay area because of its design. The concept is to always allow airflow through the heat muff to prevent burning up the exhaust pipe. That air dumps into the cowl. So, the heater flapper valve can allow cowl air into the cabin if the air from the muff is less energetic than the cowl air. Mine is like that. I had to replace the cable actuator with a lockable one because the cowl air would push the valve shut.
 
Finding Oil leaks

Buy a cheap LED Black Lite from Amazon for about $14. It has about 25 LED's and will show you where the oil is. The oil will show up milky green vs the blue from the lite. Pull your dip stick and shine the lite on it to see what fresh oil looks like.
 
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