My Cat 3126 engine and supporting frame members are completely coated with oil that I think is coming from the vent tube. I may have put too much oil in at the last change but that was more than 2k miles ago and I know I didnt add more than a quart or 2 over the recommended amount, if any. Anyway, it's making a real mess. I plan to clean it with degreaser but I was wondering if anyone had suggestions, other than the obvious "use less oil", for a way of containing the mess in the future. I'm picturing some sort of clear catch cup with a foam filter pad to contain the vented oil. It would have to be monitored and dumped before filling up to the bottom of the hose where I assume it could restrict the engine from breathing properly. Has anyone done anything like this or is there a reason it's a bad idea?
You might want to try pumping/draining some oil out of crankcase and see if it makes a difference. Don't lose sight of the fact that oil is being forced out and there may be a larger problem (e.g. blow-by). Have a great day ---- Fritz
Oil catch cans are fairly popular with the import car tuners from what I've seen. You could probably adapt one of these to work with your engine.
Oil Catch Can | eBay (http://www.ebay.com/bhp/oil-catch-can)
Oil Catch Cans | Everything you need to know and more! (http://oilcatchcan.com)
A little oil will make a big mess,and a quart or two is a lot. I'd just clean it up adj the oil level and keep an eye on it. If you over filled that's the problem and the blowby will stop .if you didn't then you need to know that too . I installed catch cans on the diesels in my boat [ got them on ebay for $10 each ] but that was to help keep the bilges clean. Gam
Here you go.You could make one of these out of PVC and put a brass drain in it.
Pittsburgh Power Oil Trap - Pittsburgh Power - High performance diesel engine (http://www.pittsburghpower.com/product_info.php?cPath=53&products_id=143&osCsid=b36a573e4f42ae88a024906394eae515)
I had the same problem--oil spread around the back of the engine compartment and across the TOAD. After doing a thorough cleaning, figured out it was the breather tube. (I won't mention what the mechanic called it!) I just rigged up a tin can fastened to the lower engine guard with a hose clamp. Then put a small plastic bottle in that and then inserted the end of the breather tube. Now I just change out the plastic bottle when I change the oil.
Rich
When our dipstick shows 1/2 low, we don't add oil, as our engine seems to blow out what it does not want, and seems to stabilize at about 1/2.
Thanks for the Catch Can ideas.
I'm 90% sure that the oil is blow-by due to overfilling but I won't be 100% until I can get it cleaned up to see if it reappears from somewhere else. If I still get oil from the vent tube then the catch can may be exactly what I need, if I can find a place to mount it correctly. I didn't know they existed. I am also going to go through the dip stick calibration procedure at my next oil change to make sure I know where "full" really is. I just added a Femco drain plug a couple of weeks ago so draining a small amount of oil would be easy but, without a calibrated dip stick, I won't know if I've drained too much. I'm thinking that with more than 2k miles since the last oil change, it's got to be about finished spitting out oil. But, I still really like the idea of the catch can and will probably try to add one.
After looking over the catch can options on Ebay, they all look too small. I'm afraid they would restrict air flow and create back pressure in the crank case. Bigger ones might be prohibitively large and expensive. Or maybe on could be modified. Your simple can idea is sort of what I originally had in mind because it never actually connects to the tube. There is always an air gap between the can and the tube that ensures air flow is not affected. Both are options that I definitely want to look into further.
At the correct level, the oil is below the spinning crankshaft. Depending on how overfilled it is, the crankshaft may make contact with the oil causing aeration with millions of tiny bubbles in the oil. Can cause a fluctuation in oil pressure and may be the cause of your mess.
I had a Tri-Pacer with a bit of blowby and it would oil the belly after a few hours. I made a little oil separator with a quick drain on it and the underside was clean after that. Don't think it was FAA approved.
Pierce
Here's a picture of my simple setup. I did need to extend the tube about a foot. The plastic bottle has a cap for closing it when I put in a new one. It's a recycled vitamin bottle. I go through vitamins faster than the coach goes through oil so I always have a spare available.
We first tried to extend the tube out by the exhaust pipe but it just spread the blow-by down the side of our jeep.
Rich
Every Aircraft I have had carries to much oil in crankcase, to satisfy FAA max oil consumption requirements x endurance at max cruise calculation. Friends debonair holds 12 quarts, blows everything out over 8 that you put in it - what a mess. My tri-pacer holds 8, everything over 6 goes on the belly. Put 8 in it and it "uses" a qt an hour, put 6 in it and it uses a qt in 25 hours.
DITTO Tim. You hit the nail on the head. pc
So, by what I'm seeing in the picture, when it comes time to empty the bottle you either loosen the pipe clamp to lower the can or cut the tie wraps to lift the tube? Easy enough. What you have is actually very close to what I have in mind but I think I want a little larger reservoir and one that I can see through. What I have in mind is a large nalgene bottle stuffed with stainless steel wool in the top half. The stainless steel wool would help to catch any atomized oil and drip it back into the bottle. I will have to look at my undercarriage to see if I can mount it the way you did or possibly hang it with a wire if that's convenient. That way I can see when it needs to be drained. Depending on how I have to mount it, I wight also consider a drain valve so the bottle doesnt havt to be removed.
The hose is reasonably stiff so it won't come out by itself but only extends into the plastic bottle by about 1/2". So I can bend it out and to the side and then remove the bottle by sliding it out of the tin can. Cap it and dispose of the old oil and then slide in a new plastic bottle and re-insert the rubber hose. Easy Peasy.
Rich
So, do you find that most of your oil drips out of the hose and not much suspended in the vapor? The can pretty well catches everything with the open top and no baffles?
Don't forget the overflow tube is called a crankcase breather. It breaths out AND IN, so don't keep the bottom of the breather tube in oil. It needs to be in air.
FWIW......There is an interesting (older) thread on this subject, albeit related to CATs. I thought the most important part of the thread was Brett's admonition to make sure that there was no chance for condensing (water) vapors to freeze up the (extended) breather opening ...... in the event the owners planned to design a fix for their CAT's "slobber tube" problems. Of course, dipstick calibration was apparently the first order of business.
The original forum has been renamed, but Brett is still the moderator....... as he has been for many years.
Diesel RV Club, an FMCA Chapter (http://forum.dieselrvclub.org/index.php/topic),6427.msg14315.html#msg14315
Wishing you safe travels...... Ed S.
I see my link didn't work. For some reason it got truncated when I cut and pasted it. I'll try again. Probably my bad. :-[
Diesel RV Club, an FMCA Chapter (http://forum.dieselrvclub.org/index.php/topic),6427.msg14315.html#msg14315
Hope the retry works.
Thanks for the link. I had actually already come across that thread as well as several other sources across the internet. They all helped me to formulate the design that I plan to try, which should be immune to the freezing problem. It should also keep the breather tube well above the oil level in the can as Barry mentioned. Current thinking is very simple and inexpensive.....a ~10" tall clear nalgene bottle for a catch can with the end of the vent hose wrapped with stainless steel wool as a baffle and inserted a couple of inches into the bottle. The bottle will be either mounted to the frame or suspended by cable, whichever is most practical after looking under the rig, so that there is at least ~6" of free space for oil to collect under the bottom of the tube. I'm still in the process of collecting the few parts that will be required and it may be a few weeks before I get a chance to install them but I will update with pics when it's finished.
This is a teensy bit off topic, but several years ago when I was getting an oil change at a Cummins place, the tech scribed a new mark on the dip stick after adding exactly the recommended amount of new oil, since he said the stamped in mark is frequently incorrect. The new mark is about 1/4" down on the dipstick, and if I fill the oil only to that mark when cold, no blow-by. If I overfill, then the engine "corrects itself", as others have noted.
Yup, calibrating the engine oil dipstick is easy and free at an oil change, and is important for verifying the correct oil level. Here is an article I wrote for the FMCA magazine several years ago:
CALIBRATING THE ENGINE OIL DIP STICK
We continue to see questions about oil "consumption" and oil on radiators and toads on the FMCA Forum and other RV websites. It seems to be universal across all brands of diesel engines.
THE NUMBER ONE CAUSE IS AN OVERFILLED CRANKCASE. CALIBRATING THE ENGINE OIL DIP STICK TO ENSURE THE CORRECT OIL LEVEL IN THE PAN "FIXES" OVER 90% OF THESE PROBLEMS.
If you "think" your engine has an oil consumption problem, you are seeing oil mist on your toad or you just want to verify that yours is correct; you need to verify that you are using the correct amount of oil. Note: the quantities listed INCLUDE the oil filter and is the total amount of oil you put in when changing oil and filter.
Now, CALIBRATE THE DIP STICK. Since the same engines/dip sticks are used in many different applications with different angles of installation, do not ASSUME that the dip stick is correctly marked. Calibration costs $0.
At the next oil change, drain oil, remove old filter (as usual). Then install the drain plug and new oil filter and add the engine's correct oil capacity LESS THE NUMBER OF QUARTS you want between the "ADD" and "FULL" marks (let's say 2 quarts). So for an engine with 20 quart capacity you would add 18 quarts. Run the engine a few minutes, shut off and wait until oil has descended into the pan (at least 30 minutes and an hour is safer). Pull the dip stick and use a file or dremel tool to mark the oil level "ADD". Add the remaining two quarts, let the oil settle in the pan, pull the dipstick and mark this the "FULL" mark.
In many/most cases, you will find that your engine "throws out" the access oil and then "consumption" settles down to next to nothing. Put in the correct amount and your "consumption" issues may go away.
This applies to all ages (including brand new) of motorhomes and boats with every brand of engine.
Also, when checking the oil level with the dipstick it is safest to do it in the morning after the oil has had all night to flow back to the pan.
Do not add oil until the level reaches the ADD mark.
Finally, make a sticker to affix near oil fill: OIL CAPACITY INCLUDING FILTER: xx QUARTS.
"bdale--So, do you find that most of your oil drips out of the hose and not much suspended in the vapor? The can pretty well catches everything with the open top and no baffles?"
Yes. After I installed the catch bottle, no more oil spots in the engine compartment or the jeep. I only collect about 4-5 tablespoons between oil changes.
Rich
You've obviously done a much better job of adding the right amount of oil than I have then. I think I could measure my vented oil in quarts, not tablespoons. I think my Cat engine may also be more prone to venting it than yours. Once I get the catch cup installed and can tell when the venting slows down or stops, I plan to mark my dipstick and then check it with a proper calibration at the next oil change. I'm hoping to get into tablespoon territory after that.
A little background. When we bought our 1993 U240 from FOT, it was 5 years old and 30,000 miles with Caterpillar engine. I was very disappointed that it "burned" a quart of oil every 300 miles.
So, I calibrated the engine oil dipstick and found out I was overfilling the crankcase by 3 quarts (i.e. the dipstick was NOT correct). I remarked the dipstick and oil consumption went to a very acceptable quart every 1500 miles and stayed that way until we sold it at 170,000 miles.
Engines WILL seek their own oil level. Overfill and they WILL puke it out the crankcase breather tube.
Part of the original Caterpillar Maintenance Presentation at FMCA Conventions, that I have been presenting for several years, includes this statement under oil capacity: Do NOT top off oil unless oil level is at or below the ADD mark (on a calibrated dip stick).
My ISB 5.9L Cummins (01' Dodge 1 Ton/40' Gooseneck 36,000 lbs. gross) has 390K currently and uses no oil when it's 2.5 Qts. low. It took 225K to get stable (broke-in/no blowby).
It runs a little below the add (hash mark) on the dip stick and uses no oil until serviced @ 8/9K.
Any more oil and it blows out.
In the early 90's I had the same design series (semi) that took over 300K before it broke in and used no oil if it was kept 4 qts. low. Service was every 18/20K and it used maybe a pint. It was running better when I sold than when it was new.
Before that KT600 Cummins, Big Cam Cummins, Series 60 Detroit, 3406 Cat, etc. & none of them liked being full of oil.. they all took a couple of hundred thousand miles to break in.
Thank you Rotella.. pc
I'd suggest fill it up and if none gets blown out you are good to go.
Early on there were no low/full marks on a dip stick.. you typically filled, then scribed the stick at the first oil service.
How many gallons are recommended for your Cummins? pc
I never ran below the add mark and do not recommend it. I understand your point.
So, probably better stated as: "Do not add oil unless oil level (as checked at least 30 minutes after engine shut down) is DOWN TO the add mark. But, clearly this would also mean that you would add oil if below the add mark. Perhaps a matter of semantics???
Here are photos of our re-calibrated dipstick, made about 10 years ago. Tube was cut and a brass compression fitting used to hold the two pieces together.
Also noted is a fix for a broken dip stick tube bracket. When the bracket broke, we found that there was way too much tension needed to force the tube back into the original position, so we added an extension to the mount allowing the tube to be positioned in a relaxed position. We also have added two support brackets near the bottom of the tube to help prevent vibration breakage at engine block.
I see the photo also shows our string that we have on every filler cap, to help us not having to look for replacements.
Photo also shows the 'vent' hose we added to the compressor governor to keep dirt, water, dust, etc from getting into the unprotected top vent hole.
@Barry Are those snacks on the frame rails for rodents so they're not tempted to chew your wiring?
see ya
ken
Ha! I was going to ask the same thing.
Ken & Richard, you guys have good eyes. . .
Yep, the toilet bowl snacks are out when we park, and there are a few more here and there that stay in place all the time. Just not sure how to keep critters from feeling at home in and around the motorhome.
Figure I never saw any unwanted critters in a home toilet bowl, so maybe it would work in the engine area. Hope they don't think it is good place to use as their toilet. Tried moth balls, but they didn't last long and smelled too much. We have seen foot prints in the dust on those engine compartment rails, so that is why we put the toilet bowl deodorants on the ledge.
Heard that having lights on at night may be one of the best ways to keep them away.
We are going to park at the Albuquerque Balloon Fiesta this weekend and those deterrents should come in handy.
How about our new engine compartment lining? I see it made a nice background for the two photos.
B&C
Barry, the lining looks very nice. That's on my to do list. We use lots of Irish spring soap bars thru out the bays and seems to work. On the plus side it smells good!
I finished my addition of a simple, inexpesive catch cup last weekend that I think will help keep things clean. It's basically a $5 Nalgene bottle from Academy, a few feet of wire cable as a harness and a couple of D-ring clips. I added a stainless steel wool kitchen scrub pad in the cup to help capture oil vapors. On my engine, there was a convenient vent tube retainer clamp about 8" above the bottom of the tube that secures the tube to the crankcase. The wire is routed over this clamp, suspending the catch cup at the right height on the tube. The whole thing cost about $10, was very easy to install and will also be easy to monitor and remove for draining. Next step is to properly calibrate the dip stick and stop overfilling but I like this as a permanent backup solution.
A recent thread dealing oil blow by and breather tubes reminded me that I should update this post with my final results on an attempt to mitigate oil coating the back/bottom of my engine and frame. The catch cup was a great idea that, for me, caught NOTHING! After several trips it was dry as a bone. As it turns out, based on diagnosis by Mustang Cat, my oil was coming from a leaking timing cover, not the breather tube. They removed the catch cup and recommended against its use in order to prevent any back pressure in the crank case. Catch cup experiment over.
Crankcase breaker "oil catchers" are fine as long as you have the same or more sq inches of outlet as the OE 1" ID breather.
Have done this on Caterpillar and Cummins engines. Surprised you got zero oil-- an ounce or so per 5k miles is pretty normal.
Yeah, I think the cup was sized ok for proper venting but Mustang wasn't comfortable with it. It wasn't catching anything anyway so I was fine with removing it. I wish the breather had been the source of the oil because the timing cover turned out to be a much bigger job...that has not been done yet. The small amount of oil and the mess it's causing don't really justify the repair cost, which was close to $4k. For now I'll deal with a few drips under the coach and continue to monitor it.
Brett,is it worth mentioning that most of the cats I have seen starting at 3306 on up to the biggest 3608 have 2 marks on the dipstick
one for full when not running and one for full at idle,these are nat gas,I would think the diesel would be the same.Maybe
somehow these 2 marks are coming into play.
At least in RV applications, the oil dipsticks are the same as most vehicles: full/add. As with any large diesel engine, one needs to wait at least an hour after shutting off the engine for all the oil to drain back to the pan. Best to check in the morning (cool and all back in pan).
But, neither Caterpillar nor Cummins provide dipsticks for RV's. So, best to CALIBRATE IT!!!
If you are getting oil out of the breather tube in any appreciable quantities it is an indication of internal wear and the resulting blow by of oil. If you are catching 1/4 cup get it checked out. Better sooner than a later rebuild.