Opening Air Cleaner

[benherman1]

Hello,
I tried to open up my air cleaners recently to see what horrors await inside but after un-clipping the first one (and some considerable percussive attempts) it wouldn't budge. Am I missing something? I was told they are oil bath filters. Since I'm guessing they haven't been touched in 20 years at least should I replace the oil? If so what should I put in it?

Ben

[Debo]

Hi Ben. Without knowing your setup it's going be be difficult to be specific, but for the most part oil bath air filters have a catch basin (or several) full of oil attached to the bottom that unclips and comes off for cleaning. Sounds like yours may be stuck after not being serviced for a while, so I'd just use some penetrating oil and try working with it to get it unstuck. It may take a few days. Just keep working and be patient. Someone else can make specific recommendations for the oil to replace it with, but generally you want to use a heavier oil so that it doesn't get aspirated into the intake of the engine. Other than that, I don't think it matters much. It's just being used as a medium to catch dust and foreign matter.

I ended up replacing my oil bath filter with a modern replaceable paper canister for ease of use/changing. There seems to be a debate about which is more effective, but I certainly know which is easier to service. If you haven't already done so, look for a PDF maintenance manual for your bus. It'll help guide you on things like this. Hope this helps.

[benherman1]

Mine has four basins attached just above the drivers side access door. I'll give them a healthy dose of penetrating oil tonight then wait for it to warm up a bit before trying again. A more modern intake seems like a good idea. I definitely have the space for it in there. Any idea where I might find a maintenance manual for a 5A? I have a paper parts manual but haven't found any others that aren't pricey yet.

[usbusin]

Where are you located?  A bus nut might be nearby.

Put your location in your signature at the bottom.

[benherman1]

I'm in Bloomington, IN. I'll update my signature as well.

[TomC]

Best if you replace with modern Donaldson or equal paper element air filter. If you ever see a picture of the giant mining dump trucks, you'll notice multiple paper element air cleaners on the front. I don't believe you can get worse then a mining truck running continuously on dirt roads.

[benherman1]

Is there anything different about the oil bath filter in this and on smaller engines? Do they do a worse job? I have a 51 Dodge and a payloader with oil bath filters and they have never given me trouble. From what I understand as long as you have oil in them and they aren't clogged (which I have never experienced) they are good to go. The 8v71 obviously moves a bit more air than the Dodge's 230 cu inch flathead but things seem to be sized appropriately with 4 basins. How often should I expect to need to service them?

If I do swap it out what Donaldson did you go with? Looks like I'll have lots of options.

[richard5933]

Asking which is better, oil bath or paper filter, is kind of like asking for favorite oil brand. You're going to get various opinions, and most are correct.

I've got an oil bath air cleaner, and it works fine. Takes about 15 minutes to service a couple of times a year. Cost is not much.

If the oil pans on your oil bath filters are stuck, it might be due to water in them causing rust. Or it could be just stuck from old oil which has gummed up.

If it were mine, I'd try using a hair dryer (not a heat gun - too hot and could start the oil on fire) to warm the bottom pans on the filters to see if you can soften any dried up oil and get the things opened. If they are rusted on, it might take a while for the penetrating oil to get in there, and then it might take a bit of physical persuasion to get them off.

Assuming that the filters are in good condition once cleaned up and will hold oil, there is no immediate need to replace anything right away.

[ol713]

  Hi;
       I have a MC-7 with the same air cleaners.  I use 40wt engine oil when servicing them.
       They are probably glued in place from age.  You might try a rubber mallet  to get
       them loose. There is a "oil level" bevel once you get inside. Also there is a large screen
       that also needs to be cleaned using a high pressure washer.  Let them dry for about
       24hrs and then reassemble. Been using mine for over 20yrs and no problems.  Dealing
       with the oil can get sort of messy some times, service them regularly will help.

                                              Good luck,   Merle.   

[dtcerrato]

Ditto on the rubber mallet persuasion - it initially worked for us but like Richard said - once you get them restored and maintain them - they're a breeze to change and maintain. Our oil bath air cleaners have work excellent w/o issue for four decades now - IMHO. Use the same oil your burning in the crankcase...

[benherman1]

I'll give the mallet a try once it warms up a bit. I mostly didn't want to do it before in case I was missing something other than the latches. I have a Mercedes with latches and a bolt which luckily held out to my attempts before I saw it... Since I'm on a pretty tight budget I'll probably stick with the oil bath unless it fall apart on me from rust. The outer two basins looked pretty oil soaked so they're likely either overfilled or have some water getting in.

[Dave5Cs]

You can get manuals here.

https://www.coachinfo.com/Coach_Manuals/MCI/MCI-manuals.html

[chessie4905]

The big GM model has three pins that ride in slots on the bottom pan. You loosen clamps and rotate pan slightly like a bayonet bulb, and then drop down/remove.
If you have no luck, I would remove while filters unit and work on it where you have more options. Then after disassembling, you can clean and paint. Careful with the mallet. You don't want to bend or dent anything. A regular hammer and a short piece of hardwood used like a chisel should work. Less chance of any damage. Control drop of pan so you don't get an oil bath.😫

[benherman1]

Dave,
Those were the ones I found and was calling pricey lol. If I don't come across any cheaper options I'll cave and buy it there. Assuming there are no copyright issues (I assume not since they are already a third party selling copies) I plan to scan in my paper manuals and get some PDFs posted to make things easier for folks here.

[Ed Hackenbruch]

Put a 5 gallon bucket under them so that if/when they fall off, the oil ends up in the bucket and not all over everything else. You might want to check and see if the passage way is clear....Scott Crosby had one that was full of crap that restricted the air flow to the engine.