What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

RV-14 EXP Snorkel help

dweyant

Well Known Member
Working on fitting the snorkel on my RV-14A EXP.

I can not get it to line up without getting in the way of the oil return line on the cylinder. Anyone have any suggestions on how they got everything to line up?

Thanks,

-Dan
 
Hi Dan,
Without seeing your setup, I'd be willing to bet that you aren't going to get it to line up without conflicting with the oil return line. On mine, my snorkel interfered with both the oil return line and the starter solenoid. You will find some discussion of this topic within this forum. Some suggest that you can bend the oil return line, others suggest you replace the tubing with wire braid flex hose, and yet others suggest cutting the snorkel to create clearance and then glass it back together. I took a somewhat hybrid approach. Where the oil return line and starter solenoid touched my snorkel, I cut a slot, then installed the snorkel and used both the oil return line and starter solenoid as "molds" to reglass the snorkel around them. My thinking is that you don't want to interfere with the air flow in the snorkel any more than is necessary because it will affect the horsepower your engine can develop. This left some minor speed bumps on the inside but maintained the overall general shape. Lots of options but I can't say which is best. I contacted Vans about my situation and they said the snorkel fit on their prototype. Just goes to show the variability in snorkel manufacture and various engine configurations.
 
The EXP snorkel has a bit of interference with the oil return line of #2 cylinder but should not have any issues with the starter, mine did not.
I personally did not like VANS instruction of how the process of fitting goes and modified it slightly.
But in regards to the oil return line, I disconnected it to get the snorkel fitted first than I was able to turn the 45 degree elbow just enough to create enough clearance but some folks have reported that they had to build a new line which is very easy to do.
 
I had that problem with my IO-360. In my case, I shortened that first section of the tube which has the B-nut (flare fitting) by 1/2" or so and re-flared the end. That pulled it in towards the cylinder head just enough to clear the snorkel. Slightly re-formed the S-bend on the bottom to accommodate the shorter first section.
 
Working on fitting the snorkel on my RV-14A EXP.

I can not get it to line up without getting in the way of the oil return line on the cylinder. Anyone have any suggestions on how they got everything to line up?

Thanks,

-Dan

I used a hair dryer to warm up the snorkel and change its shape slightly. 10 minutes job
 
I had that problem with my IO-360. In my case, I shortened that first section of the tube which has the B-nut (flare fitting) by 1/2" or so and re-flared the end. That pulled it in towards the cylinder head just enough to clear the snorkel. Slightly re-formed the S-bend on the bottom to accommodate the shorter first section.

I did something similar to my return tube. It would be a quick fix for VANS to work with Lycoming to have the return tube shorten at the factory. I had other issues with two of the other return tubes rubbing up against the lower heat shields on cylinders 1 & 2. A slight twist fixed the rubbing issue. But, a quick note to Lycoming QA from VANS would fix this.
 
I did something similar to my return tube. It would be a quick fix for VANS to work with Lycoming to have the return tube shorten at the factory. I had other issues with two of the other return tubes rubbing up against the lower heat shields on cylinders 1 & 2. A slight twist fixed the rubbing issue. But, a quick note to Lycoming QA from VANS would fix this.

I doubt this would happen (but I don't know whether it has been tried).

A lot of people assume that Van's is a huge customer of Lycoming and therefore has the pull to get them to make design changes, etc.
Van's does buy a lot of engines compared to many other OEM's but it is still only a small portion of all of the engines that Lycoming produces.....

I have posted about this before but will again for those that have never heard.
The drain back tube for cyl #2 is the same part that is used on a lot of different Lyc. engines (4 and 6 cyl.)

When the original RV-14 Snorkel was developed, its final shape cleared the standard drain back tube that was installed on the first IO-390 that Van's purchased and installed in the RV-14A prototype.

When the EXP119 option was developed, the orig. snorkel shape was used as the basis for the new snorkel that had to be adapted to interface with the AFP200 servo. This new snorkel cleared the #2 drain back tube on the first EXP119 engine received from Lycoming.

It wasn't until a second EXP119 engine was purchased for the RV-15 prototype that an interference was discovered.

What changed?
Nothing was changed on the Snorkel so the only possible explanation is that the drain back tube installed by Lycoming is not always the same shape.

Not surprising really since in most installations there is no clearance sensitivity on this part.

Knowing this, it seems the manufacturing tolerance for this part is fairly large so even if Van's was able to negotiate a design change I don't think there is any assurance that every one would still clear the snorkel (Those of us at Van's that worked hands on with the engines had been prodding them for years to quit using the stupid screw clamps on the drain back tube coupler hoses, and switch to constant compression clamps. Last I checked they were still using the same clamps they always have :rolleyes:)

When we were under a time crunch to finish the RV-15, and we had begun to hear about builders having an interference, we took the opportunity to proof out the Aircraft Specialty custom tube and confirm it was a viable option for builders.
Another option that has been tested successfully is cutting the flair plus a small amount of length off outboard end of the tube, re-flare, and then make a very minor shape change bending by hand to get it where it needs to be.
 
Last edited:
Reading this thread is a testament to the amazing improvements Van's has made with the later kits like the RV-14. With the earlier kits, the instructions were closer to "Now, choose and install an engine and prop. Good luck!" :D
 
Back
Top