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Oil Filler Tube Replacement/Repair

precession

Well Known Member
(I’m not sure this qualifies as an issue for the “ongoing maintenance” forum, so I’m posting it here.)

The original builder of my RV-4 installed a new 0320D1A; however, the oil filler tube he got was apparently not long enough to come up to the oil filler access door on the cowling. So it looks like he cut the tube, then epoxied in a 3" piece of PVC tube to provide the extra length. After 25 years, the epoxy was breaking down and the tube leaking some oil at the joints, so I pulled it off. (See photo.)

I suppose I could epoxy in a new piece of PVC, but I’d much rather have an oil filler tube of the correct length so I don’t have any joints in it. Can I get one? If so, where? Thanks.

(Edit: my photo didn't post, but all it showed was the oil filler tube and the piece of PVC the orig builder used)

ifaSQU
 
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Oil tube

Contact any engine rebuild shop or preferred airports for a used one
 
Be sure to recalibrate your dip stick after replacing the tube!

Thanks, good point.

I contacted Preferred Airparts, who referred me to engine shop G&N in Indiana. They are looking for a used oil fill tube for me now.

For anyone with a -4, the part number for a 10.57" tube is 75767, and they tell me the threads at the base fit both the 0320 and 0360 series engines. I think the 10.57" tube will just barely fit under my -4 cowl. I also found reference to this part number in another VAF thread on the same topic: http://www.vansairforce.com/community/showthread.php?t=94036.

As for the dipstick, although I could recalibrate my existing one, I asked them to try to locate me one that is already mated with the 75767 10.57" tube. Reason: my existing dipstick is no longer firmly attached to the cap at the top; therefore, when the engine is running the dipstick is vibrating and rattling around and maybe hitting the engine case, causing slight wear on the stick. Possibly this could lead to small pieces of metal going into the sump(?).

My hangar-mate replaced his dipstick for the same problem. He noticed it was loose from the cap and there was a worn area on the shaft where it apparently vibrated against the engine case. I'm imagining this must be pretty common. Not sure how many people regard it as a problem though(?). Those dipsticks are expensive - apparently over $100 for a new one I understand. Hoping they'll locate a used one for me.
 
A number of years ago someone posted that the aileron pushrod tube size was just right to use to extend the oil fill tube. The tube I received from Vans (old kit) had an extrusion error mid-length and was unusable for the pushrod. The majority of the tube is good though, so I have spare tube. I sent him a section. If the used replacement doesn't work out I am happy to send a chunk to you as well so you can replace that PVC with aluminum. Just let me know.
 
Deteriorated epoxy/glue going into oil sump?

A number of years ago someone posted that the aileron pushrod tube size was just right to use to extend the oil fill tube. The tube I received from Vans (old kit) had an extrusion error mid-length and was unusable for the pushrod. The majority of the tube is good though, so I have spare tube. I sent him a section. If the used replacement doesn't work out I am happy to send a chunk to you as well so you can replace that PVC with aluminum. Just let me know.

Thanks for the offer, Colin. I'll see how I do at getting a new tube and go from there.

Actually, the reason I'm looking for a tube of the correct length - rather than epoxying a new extension sleeve back on (either PVC or aluminum) - is because of what happened when I took my tube apart. Obviously, the extension sleeve (PVC or aluminum) slides over the outside of the plastic Lycoming oil tube, and then has to be affixed to the tube via glue or epoxy. When you do that, there will unavoidably be a good amount of epoxy/glue that dries on the inside of the oil tube and becomes hard. I found a good amount of it inside my tube. Now you have to hope that hard glue/epoxy does not come loose or break down over time due to heat, age or exposure to oil, and drop down into your oil sump. I'm guessing, without knowing, that mine never did before I started messing with it(?). But when I pulled it apart I had to break the remaining epoxy and I found loose, broken pieces of hard epoxy inside the tube - almost like little pieces of sand or gravel. Did any shards/pieces of that stuff drop down into my sump when I pulled it apart? I don't know, but as a precaution I'm going to drain the oil and refill.

It sounds as if many people have glued on extension sleeves, so I guess it's considered acceptable practice. But (a) I don't know what epoxy/glue is recommended, and (b) personally I'm not really comfortable with the idea of hoping the stuff that dries on the inside of the tube doesn't become loose in the future and drop into the sump, possibly as hard pieces of grit. Not sure how much others have given consideration to this.
 
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Tube

Try Colorado Air Parts 970-874-7575 for used or Dart Aircraft 254-753-1810 for new Superior or ECI
 
Call Ilene at enparts. She ususally has anything engine related you would ever need cheap. 972-227-0086
 
For anyone with a -4, the part number for a 10.57" tube is 75767, and they tell me the threads at the base fit both the 0320 and 0360 series engines. I think the 10.57" tube will just barely fit under my -4 cowl.

I shortened the standard filler tube on the IO-360 on my -4 to 9-3/4 inches. I feel it is still about 1/4? too long. I don?t see how a 10.57? part would fit unless we are not talking about the same reference points.
 
I had to be away for a few days. Thanks for the replies/suggestions regarding suppliers, jrs14855 and titanhawk.

Dean Pichon, my builder also rigged up his oil tube so the completed length was 9.75 inches (before addition of the cap), just like yours. I measure 1" of clearance between the top of my cap and my oil filler door. I was therefore figuring I could tolerate a 10.57" stock tube. That would leave me with a 0.20" clearance. Not much clearance at all, but I thought it would be okay; it would be nice to have a stock, one-piece tube.

However, it's since occurred to me that I may need new motor mounts in a year or two. If so, that might raise the engine up such that the cap on the tube would cross that small clearance and hit the door(?). Therefore, I'm rethinking getting a stock 10.57" tube.

My research indicates there are only 3 Lycoming stock tube lengths available for these engines, which are:

Part Number - 75767 Length – 10.57”
Part Number - 75735 Length – 6.32”
Part Number - 75736 Length – 11.57”

I guess that explains why people have been forced to cut tubes and fit them with sleeves to fit an RV-4. I also found (although the engine shop guy I contacted said he'd never heard of it) that Lycoming apparently makes a couple of "oil tube extenders" (sleeves). So I guess affixing a sleeve is considered standard practice by Lycoming(?).

Oil tube "extenders":
Part Number - 75737 Length – 2.69”
Part Number - 75761 Length – 4.47”

So it looks like I'm going to be forced to put a sleeve (of PVC, aileron tube, or stock Lycoming extender) back on my tube.

I'm going to try another engine shop to try to find out what epoxy is recommended for attaching the sleeve. If someone here knows or has a suggestion, I'd like to know. I still don't like the idea of having epoxy inside the oil tube that could possibly break down over time, lose adhesion to the tube, and drop into the sump. But apparently that's not considered a concern(?). I don't know why.
 
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TUBES

You could put two of the 75761 tubes together and it would be right at 9 inches. You would have to mark your dipstick as there is not a stock one that take two of those tubes. The threads wear out on the dipsticks before the tube and in most cases that is the reason for the wear on the stick. I have several of the tubes and should have a dipstick that could be remarked as well.

Jesse
970-874-7575
 
Thanks, good point.

I contacted Preferred Airparts, who referred me to engine shop G&N in Indiana. They are looking for a used oil fill tube for me now.

For anyone with a -4, the part number for a 10.57" tube is 75767, and they tell me the threads at the base fit both the 0320 and 0360 series engines. I think the 10.57" tube will just barely fit under my -4 cowl. I also found reference to this part number in another VAF thread on the same topic: http://www.vansairforce.com/community/showthread.php?t=94036.

As for the dipstick, although I could recalibrate my existing one, I asked them to try to locate me one that is already mated with the 75767 10.57" tube. Reason: my existing dipstick is no longer firmly attached to the cap at the top; therefore, when the engine is running the dipstick is vibrating and rattling around and maybe hitting the engine case, causing slight wear on the stick. Possibly this could lead to small pieces of metal going into the sump(?).

My hangar-mate replaced his dipstick for the same problem. He noticed it was loose from the cap and there was a worn area on the shaft where it apparently vibrated against the engine case. I'm imagining this must be pretty common. Not sure how many people regard it as a problem though(?). Those dipsticks are expensive - apparently over $100 for a new one I understand. Hoping they'll locate a used one for me.

Dipstick is a taper press fit to the cap.....

Tap back into place, drill and pin it to the cap.

A new unmarked dipstick rod can be purchased at any ACE hardware store.
 
I had to be away for a few days. Thanks for the replies/suggestions regarding suppliers, jrs14855 and titanhawk.

Dean Pichon, my builder also rigged up his oil tube so the completed length was 9.75 inches (before addition of the cap), just like yours. I measure 1" of clearance between the top of my cap and my oil filler door. I was therefore figuring I could tolerate a 10.57" stock tube. That would leave me with a 0.20" clearance. Not much clearance at all, but I thought it would be okay; it would be nice to have a stock, one-piece .

It?s important to maintain some clearance between the dipstick and the oil door. I have about 1/4? and still see signs of occasional contact- probably during start up.

Good luck,
 
One option may be to buy a Superior oil tube that comes in metal and cut it to the length you want - then have some sort of aluminum fitting machined to join the two parts.

http://www.aircraft-specialties.com/tube-oil-level-sl75767/

Thanks Gil, I kind of like the idea of the aluminum Superior tube (no plastic threads to possibly wear out, although mine never did), and the one you linked to is a little less than the plastic Lycoming one ($76 vs $84). I'd still have the length issue to deal with. I called Superior to check if they make different tube lengths (no, they only make the 10.57"), and the rep suggested I could also have the 10.57” aluminum one cut and welded to my existing 9.75” length. Not sure what a welder would charge for that, but that would mean my existing dipstick would be correctly calibrated.

Meanwhile, the Superior rep knew of the Lycoming plastic extenders (which Superior does not make). He said the tubes join to the extenders by way of threads not glue/epoxy (maybe I should have figured that out if I’d thought it through), so unlike a homemade sleeve extender, you won’t end up with dried epoxy inside your oil tube (waiting to possibly break down and fall into your sump?) – which I found interesting. By the way, the plastic extenders alone are $53 new on top of what you pay for the plastic oil tube. A piece of PVC is sounding better all the time. :)
 
You could put two of the 75761 tubes together and it would be right at 9 inches. You would have to mark your dipstick as there is not a stock one that take two of those tubes. The threads wear out on the dipsticks before the tube and in most cases that is the reason for the wear on the stick. I have several of the tubes and should have a dipstick that could be remarked as well.

Jesse
970-874-7575

Thanks Jesse, it sounds like you're saying two of the 75761 extender tubes could be threaded together to result in a 9" tube and you may have a couple. That length would be a little less than ideal but might still be acceptable. I'll give you a call.
 
If you start with the longer tube and cut it down the ends would butt together at the joint. You could clean out any squeeze-out once the epoxy cured. At that point, the likelihood of contamination would be very low.

Another option could be a custom-made tube. For the most part it would be a pretty easy lathe project. Cutting the threads would be the only challenge (at least on my lathe, mine doesn't have a quick-change gearbox). If I had that same problem, that is what I would probably do, but I have the tools for it.

The weld-together solution is good as well. Probably $50 to get it welded if you have the parts all fabbed up and ready. Ask the Superior rep what alloy they use for the tube.
 
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I used CPVC cement to splice my filler tube. To avoid getting it inside the tube, you apply the cement on the outside of the tube at the cut, and push the joining sleeve over the tube. Do the same on the other side of the splice and there won't be any glue inside the tube. On mine, I also used 3 hex screws on each end of the coupling to provide a mechanical connection to the tube.

Ones like these, in an appropriate size:

https://www.build.com/delta-rp25620...MIzZ2lhv_L3QIVClYNCh1hEwv5EAQYBCABEgJLlPD_BwE
 
I used CPVC cement to splice my filler tube. To avoid getting it inside the tube, you apply the cement on the outside of the tube at the cut, and push the joining sleeve over the tube. Do the same on the other side of the splice and there won't be any glue inside the tube. On mine, I also used 3 hex screws on each end of the coupling to provide a mechanical connection to the tube.

Ones like these, in an appropriate size:

https://www.build.com/delta-rp25620...MIzZ2lhv_L3QIVClYNCh1hEwv5EAQYBCABEgJLlPD_BwE

There are about 2,000 EZ's flying around with shortened filler tubes using this method, plus an 3-4 ply epoxy/BID "Ace bandage wrap" on the outside. Mine was done 35 years and 3,500 hours ago; still fine.
 
There are about 2,000 EZ's flying around with shortened filler tubes using this method, plus an 3-4 ply epoxy/BID "Ace bandage wrap" on the outside. Mine was done 35 years and 3,500 hours ago; still fine.

I can't believe those guys stole my idea! ;-)
 
Tube

The thread on the top of the dipstick cap is different than the thread where the tube threads into the engine. Therefore two of the short tubes cannot be used together.
The rod portion of the dipstick is a light press fit into the cap. The upper end of the rod must be machined to fit tightly into the cap. I used 6061T6 for the replacement rod.
The best way to mark the dipstick would be an engraving tool.
 
Thanks to Precision for listing the part numbers for the stock tube lengths.

Sad that Superior doesn't make an aluminum tube in the 11.57" length. I guess I am stuck with my std Lycoming plastic one.

I need to change the gasket where it screws into the case. p/n 72059
 
"Press fit " thread #22

My new superior 360 A1A came with a ROLL PIN in the stick / cap joint. Press fit might be ok but obviously Superior chose "belt and suspenders" in this case.
 
Oil tube Dynafocal Mount interference RV4

On my RV4 I have a shortened Lyc tube with sleeve. I bought the Superior 10.57? tube to replace the plastic modified Lyc tube but the longer tube contacts the vertical mount arm between the the upper and lower Lord mounts. Anyone else had to deal with this? I am considering having a machinist fabricate a piece of aluminum that would thread into the engine with a threaded offset of 15 degrees for clearance. Any feedback would be appreciated
Thefreddy
Dues happily paid 2019
 
Don?t know if you ever got it figured out, but I had the same issue on my RV3
I got a 73735 6.32? tube and the 2.69? extension. The longer tube screws into the extension, which then screws into the engine case.
This assembly was just the right length for my RV3 installation. Would probably be the correct length for the RV4, too.
I now have a spare 75767 tube.
 
I did have a problem. The flats on the tube, for the wrench to tighten, was bumping on the motor mount. So I had a friend chuck it up in his lathe and turn off the flats. After that it fit fine. Still close but so far no rubbing after 57 hours.
 
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