why is my airfilter ful of oil ?

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diymirage

diymirage

HP@idle > hondaHP@redline
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so I took the tarp off the duster yesterday and ive been cruising about a bit
shes allways used oil and been hard to start once warm

I went to check the slack on the throttle cable and when I removed the airfilter about a cup of oil fell out

I cleaner out the breather and installed a fresh PCV valve before I put her away for the winter so what should I look at first ?

 
My Dart /6 does the same thing. Replaced the PCV valve and the other valve cover breather cap and it helped. Make sure your good and tuned up and your carb is tuned as well so you have the best vacuum she'll produce. Also adjust your valves if you haven't already done so. That's about all you can do. Just make sure she's running the best she possibly can and keep the oil changed and clean. The basic problem is blow-by from your rings. You can perform a compression test and a leak down test to determine the severity but it just comes with age.
 
diymirage said:
I cleaner out the breather and installed a fresh PCV valve before I put her away for the winter so what should I look at first ?
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Not a bunch you can do, it's sucking it up through the PCV and depositing it in the air cleaner. I don't know if the /6 has a baffle under the PCV in the cover or not, if it did, and it isn't there, that might be part of it.

I haven't messed with a slanty in about 35 years.
 
haven't done a valve adjustment yet
(I should look into finding the proper info on that)

to be honoust, the old slanty hasn't received quite as much attention as the 360 that will replace her but that doesn't mean I want to wreck her
 
ill look for that baffle also, shouldn't be hard to fab if it is not there
 
Lol, good luck with wrecking it, those things are about indestructible. I actually tried to blow one up way back when, and couldn't, it was like the Energizer Bunny, it just kept going.
 
This does not 'just come with age' unless the compression rings are totally shot; this is a distinct fault. The oil there can come via faulty PCV; being new does not mean it is working right. It should flow air at moderate vacuum levels and not flow air at no vacuum or very high vacuum. Likely the PVC is not opening in the moderate vacuum ranges, and the only way that the oil vapors can get out is via the open breather that comes into the side of the air cleaner; it'll fill up the cleaner like you see.

Also, the port under the carb to which the PCV hose connects can get clogged with burned oil vapors and needs to be cleaned out; take the large PVC hose off of that port and make sure air flows freely into there. If not, you need to clean/dig it out.

And make sure the PVC is not backwards.......

Otherwise, perhaps you have sticking compression rings in 1 or more cylinders from gumming and varnish and sitting. Try half a container of Rislone or Sea Foam poured slowly down the carb while keeping one hand on the throttle to keep things revved up to 1500-200 rpm. It'll smoke like hell but may help clean a sticking ring and will clean the intake valves. Then put the rest in the crank case and drive around. It probably will not be the issue, but the copious smoke is fun......
 
i remember doing this on my car, I had to adjust my timing and adjust my carburetor. I adjusted the mechanical advance 35 degrees, and vacuum advance 15-20 degrees. Make sure the carb isn't running rich and the float is good. I also replaced my timing chain at this point, because it had a lot of slack, which contributed to other problems

Don't condemn the rings before checking this stuff, because it could just be running rich.
 
Mmmmm..... running rich won't put oil into the air cleaner..... perhaps the original symptom is getting lost in the answers LOL

Glad you changed the timing chain, Kid. How did it change engine operation? (Like I don't know....LOLx2)
 
allright guys, I did a little bit of trouble shooting tonight and this is what I found

there are baffles under the PCV valve as well as the breathers

there is a good vacuum coming from the big hose on the bottom of the carb running into the PCV valve (and with that hose disconnected it will not idle)

the PCV valve itself is installed correctly (the metal valve part is vertical in the plastic housing, if that makes sense)



what might be the best indication of the problems is when I pull the top of the airfilter off there is a oily mist coming out of the breather hose

I swapped out the breather and that did not help



I did NOT check into valve lash yet (don't have a valve cover gasket on hand and I don't want to be down a few days on the count of that)

I also did not adjust the timing on the account of me not having a timing light and I did adjust the carb, but only so that it no longer idles at 1200 RPM (didn't get a chance to check into the AFR setting)
 
make sure you put the oil in the engine and not:

 
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BLLOWWWW BYYYY!... Sorry to say, Combustion is getting past the rings. You can try to help it by making sure the PCV system is working at its best but anything short of a rebuild isn't gonna do much.
Make sure the VC baffle isn't clogged up with sludge or deposits. If the oil can't drain back fast enough the vacuum on deceleration can pull the oil out from the baffled area of the VC & it ends up in the air cleaner.
 
almost forgot to mention...on the bright side, I took about 1/4 inch of slack out if the throttle cable and now the car moves a whole lot better :)
(does seem to shift a little harder though)
 
Lonewolf is exactly right. It's just worn out.

The PCV system functions by creating a circular airflow path. One "end" is the vacuum port on the carb, the other "end" is the large hose that draws air off the aircleaner.

The vacuum signal at the carb port draws air from the aircleaner, through the almost never-cleaned valve cover inlet breather, through the crankcase where it picks up blowby gases, out the valvecover via the PCV valve and into the intake to be burned.

What is happening is that there is too much blowby for the PCV valve to handle, so the combustion pressure seeks another way out which in this case is the wrong way through the crankcase breather. So, all that oily mist is ending up settled in the bottom of the aircleaner.I bet if you take the oil cap off with it running it'll sound like the exhaust coming out of the oil filler.

You can band-aid it but that's essentially just figuring out how to hide the oil blowing out. I had a 231 Buick once that had so much blowby that it would ruin the air filter element in 500 miles. I ended up disconnecting the valve cover breather hose and extending it with a piece of heater hose down behind the front tire. After that any time I sat at a light there was a nice oily haze drifting up beside the car:D
 
When it wears a little more it will start to pump out of the dipstick tube. I just put a hose on it and catch it in a milk jug. Then pour it back in. After a while the compression went to nothing and that was it. No go no mo'.
 
put 2 spuds into the top of a catch can and route the breather hose/PCV through it, itll catch the oil and hold it until you return it to the crankcase. Band aid for sure but it will "stop the bleeding"...literally. The Seafoam treatment is worth the money, even if its for entertainment value.
 
Id like to revisit post 11. In it you say the engine quits running when you take the PCV hose off the carb. But does it also quit running if you pull the hose off the PCV. I have seen the hoses themselves plug up.
I think nm9 has a good idea re the seafoam treatment. and hes probably on the money too about the engine wanting to retire. Esp. since you mention hard starting, and blowby in the same post.
I had a slanty like that.It was beyond worn out. I Removed the PCV and gutted it. Then fit a restrictor in there. Now it was a continuous crankcase ventilator. That cleaned up the idle. Didnt do anything for it though under power. It left a pretty good trail.
 
AJ/FormS said:
Id like to revisit post 11. In it you say the engine quits running when you take the PCV hose off the carb. But does it also quit running if you pull the hose off the PCV. I have seen the hoses themselves plug up.
Click to expand...

I actually pulled the hose off the valve while leaving it connected to the carb and there was some good vacuum there



I just adjust the valve lash and I noticed another "clue", I could use the fan to turn the engine
im not sure how much compression a /6 should have but it seems to me that shouldn't be possible right?

(that would indicate worn or sticky rings like some have mentioned)



ill pick up a can of seafoam on the way home and see if that helps me any...if it doesn't ill install an oil catch can and hurry up with the 360

thanks for all the help guys
 
One test you can do for the compression rings being shot is to just accelerate hard; you will pretty much inevitably get a lot of smoke out the exhaust with shot compression rings under hard acceleration.

Your PCV hose to under the carb sounds OK and clear. I would still replace the PCV and make sure you have the right part. Mkee sure you can blow through it towards the carb.
 
diymirage; I just adjust the valve lash and I noticed another "clue" said:
Putting pressure on the belt and turning the fan was EXACTLY how I used to set the dual points on my Commando 273. Very precise method to get the points rub block on the highest point of the distributor cam.

When I got my "new" 64 Valiant I tried the same thing and the 225 wouldn't budge a single degree so now I'm jealous.

Now that I think of it.....what is the first thing it says in the lawn mower owner's manual when removing the blade? A: Disconnect the spark plug wire. Oh well, I still have all ten digits.
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Depends on how hard you have to turn it and press on the belt. I can do it on my fresh rebuild.... but just barely and with lots of tension on the belt. With the old rings, it was not so hard.
 
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