Oil bath filters. How bad are they?

[jsharp]

Ok so I just bought an old tractor and it has an oil bath air filter. It also has a recently rebuilt engine and I'd like to see it run a while.

I have believe the oil bath filter is about 1/16 step better than nothing, if that. But I don't know.

Does anyone else here? Should I try to figure out a way to adapt a real paper filter and housing to it?

 

[Shannow]

They certainly end up with a lot of dust in them.

I think that properly serviced, they weren't all that bad.

 

[Jim Allen]

I know of one SAE J726C test done back in the '80s that compared an oil bath filter to other types. Unfortunately, it's unattributed (but was likely underwritten and published by K&N), so we can't "bovine scatology" test it. According to that test, the oil bath did poorly in catching small particles and in airflow capacity. In other ways, it was equal to the other filters tested. There were many different types and qualities oil bath filters over the years, some better than others, no doubt. I flow tested a few types from Jeeps and Land Rovers and found them to be extraordinarily restrictive. I had no way to test filtering ability. I did discover that when the oil level was lowered, or no oil was installed, the airflow capacity increased. I'm sure that came with a lessening of an already poor filtering ability. I'm also sure the engine would be better off with a paper filter (choose one from a larger displacment engine) but wonder if it's worth the trouble to convert. Think about this: It took decades of hard work to kill the original engine with the OE filter. I'm sure with you, it will lead a much more pampered life than it did previously. If you keep the oil level in the oil bath as specified, and clean it regularly, the tractor is likely to still outlive you! Anyway,

your choice.

 

[jsharp]

Thanks for the info guys. Jim, I've had the same thoughts as you. The tractor is 45 years old and as far as we can tell, the first time the engine was gone through was 3 years ago. It's had minimal use since then. Since I'm 51 now and won't be using it hard, I'm doubting I'll see the next rebuild...

 

[mechtech2]

They are not good for racing, where flow is important.
But, you are never out of luck obtaining the correct filter in far away places!
Keep it at the correct level with clean oil.

 

[Lazy JW]

You won't want to sit on that tractor long enough to wear it out using the stock oil bath filter. Trust me on that one.

The old air-cooled Volkswagens used an oil bath air cleaner and no oil filter. It was normal to drive those well in excess of 100k miles back in the day when 100k was considered good on Detroit iron. I have personally driven VW's way more than that with low oil consumption and good compression. If oil bath air cleaners were so bad this would not have been possible.

That said, a good paper filter is better. But not enough to get me to ditch the oil bath just to buy a paper filter setup.
Have fun,
Joe

 

[XS650]

Quote:

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You won't want to sit on that tractor long enough to wear it out using the stock oil bath filter. Trust me on that one.

The old air-cooled Volkswagens used an oil bath air cleaner and no oil filter. It was normal to drive those well in excess of 100k miles back in the day when 100k was considered good on Detroit iron. I have personally driven VW's way more than that with low oil consumption and good compression. If oil bath air cleaners were so bad this would not have been possible.

That said, a good paper filter is better. But not enough to get me to ditch the oil bath just to buy a paper filter setup.
Have fun,
Joe

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That would also be a good argument for not using an oil filter. Do you think that maybe VW was using better engine materials the Detroit back then?

 

[Lazy JW]

I "believe" that VW was using superior materials back then. But Detroit and Tokyo both caught up later. Nowadays it is still possible to drive an air-cooled VW well over 100k miles but if that's all we get out of newer cars we think we got ripped off.

I do believe this points out that an air cleaner plays a much bigger part in engine longevity than does an oil filter.

After I get my 69 bug back on the road (transaxle growling) I plan to install a bypass oil filter.
Joe

 

[Jim Allen]

LazyJW: Your assertion that aircooled VWs were routinely getting 100K miles back in "the day" is completely at odds with what I saw. I was a VW tech in the '70s and worked at a VW dealer in California and a several independent VW shops. Basically, I got rich rebuilding aircooled VWs and seldom did they make it past about 60K.They were pretty cheap to rebuild, but still...

I saw some carefully maintained Vee-Dubs with 100K, but you had to change the oil at 1500-2000 miles and use the best you could find (it was only 3 quarts) and never get it hot (not easy to do in sunny California) in order to do that. If you had a bus, you were lucky to get it past about 40K. I bought a perfect, lovingly maintained '71 Westphelia Camper bus with 70K miles at a bargain price because the owners, who travelled a lot, brought it in for their fourth major engine failure and finally had enough. I then built a modified engine for it (modified for durabilty, not power, with a full flow oil filter and cooler,free flow exhaust, increased lube capacity and airflow improvements.). It wasn't fast but could be run hard without damage.

I loved the old VWs but I am realistic about their traits. Engine durability wasn't one of them, I don't think. At least up unti the Porsche motors and the wasserboxers.

 

[jsharp]

I had a '60 VW and a number of friends had assorted mid to late 60's models. Our experience was as Jim's. Every one of them was past tired at 50-60K miles.

Those cars had plenty of novelty but that's the extent of it IMO.

Thanks all for the comment on the oil bath filter. I believe Lazy JW has it right. No way will I be sitting on that tractor long enough for it to matter...

 

[Lazy JW]

Quote:

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I had a '60 VW and a number of friends had assorted mid to late 60's models. Our experience was as Jim's. Every one of them was past tired at 50-60K miles....

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Reckon I've just been lucky for the past 30 years. I've always changed the oil at 2000 miles and my commutes have been 30+ miles each way in a cooler climate than southern Cal. I keep a complete logbook recording all fuel, expenses, maintenance, etc. My 68 Bug averaged just over 32 mpg total over 110k miles, never opened the engine up. Traded it to a friend who is still driving it. Newer cars are better in almost every category though.
Joe

 

[T-Keith]

Old tractors can handle a lot of abuse and still keep going. I'm guessing it's not used enough to worry about it "wearing out" So even if it's not the best, does it matter? I've seen old John Deere two cylinders with the bores worn oval and they still ran good.

 

[JohnBrowning]

that tractor's engine has steel pistons with full length skirt's etc...... You will be fine so long as you service it properly.

 

[Shannow]

Quote:

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After I get my 69 bug back on the road (transaxle growling) I plan to install a bypass oil filter.
Joe

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bypassing what ???

the engine

 

[Chris142]

Back to VW's.
My dad bought a 1970 Super Beetle new. Drove it 120K using Pennzoil 10w-40 changed every 4K. He removed the engine to restore the car in the 80's and has not touched it since.

Cyls still have hone marks and it did not use any noticible amount of oil.

In 74 he bought another Super Beetle new and drove it 145K on Penz 10w-40 just like the 70. He wrecked it in 82 and it was running fine. Neither had more than regular maintenance and both went up Cajon Pass daily in 100+ temps.

 

[Towel_Rail]

I like oil bath air filters, myself. They'll trap particles down to the microscopic level, breath enough for low-RPM use, and replacement elements are easy to find.

I'm sure you'll agree, Jim, that missing tin and owner neglect cost those '60s VWs engines a lot of life needlessly. Too bad VW didn't wise up to oil filters until the Type IVs...

- Scott

 

[Jim Allen]

I acknowledge that owner care was the key to longevity on the old V-Dubs, but the real world was that it took an extraordinary amount of care, compared to the average car (especially a Detroit Road Barge), to get 100K miles out of a powerplant. VWs in cool climates seemed to do best and have the easiest time. They just fried in California and other hot places. Can't tell you how many times I pulled cylinders that had turned blue and cleaned out crankcases full of carbonized oil... even when all the tin was in place.

I'll grant you that the operator of any vehicle needs to adapt to a car in terms of maintenance and driving habits. For that reason, from a purely practical standpoint, it was hard to get on the VW bandwagon because there were so many cars that equalled or exceeded the performance WITHOUT all the extra aggro (read the Japanese imports). That's especially true considering the way most people buy, drive and sell their cars. For all that, I still loved 'em and that subjective "Beetle" cachet (plus some absolutely BRILLIANT mareting people) is why they sold so many. For the average person in a hot climate, though, practicality soon came along to bite 'em in the glutes. To bad they didn't come up with something like the new Beetle back then. All the cachet and top performance and reliability to go with it.

 

[Towel_Rail]

Yeah. If they'd stuck with the waterboxer and kept improving that, we might not know the name Subaru today.

 

[Gary Allan]

It took an inordinate amount of care to get a Detroit Iron to make it to 100k. Well, let's say that if you took good care of them it was not too hard ..but you didn't have to take too much care of them to allow them to function in a dysfunctional state. The thing was that the typical Detroit Iron could have 4 out of the 8 cylinders dipping their paddle and still provide enough power for you to move the thing. Very few drove 10k a year "back in the day" and getting to 100k was a challenge. That's why it was so remarkable a benchmark to achieve. The original owner was usually done with them by 50-60k. By the time you were on the 3rd owner ..many other issues usually came into play.

The main problem with the Beetle engine, IIRC, was that one cylinder had some cooling disadvantage due to the shroud configuration. They were fine if you didn't have to idle them too much. I also imagine that sustained higher speed driving could eventually result in the same issue.

 

[Jim Allen]

Gary: Inordinate amount of care? C'mon, Gary! An oil change every 3000, points & plugs at 10K... , air filter, fuel filter, normal stuff. Practically every American car in that era made it to, or near, 100K. Worst case, a $100 valve job. Making a VW live a long life on the original engine depended a lot on climate and care. The VW was built for a cooler climate and did best there. Out west, toastorama. The Grapvine, north of LA is littered with bones and ghosts of the dead VWs that tried to climb it in the summer with inattentive drivers. To make an old VW live past 40-50K in a hot climate, it required 1500 mile oil changes, valve adjustments every 5-6K, plus all the normal stuff listed above, plus a careful driver that took note of ambient temperatures and eased the workload on hot days.