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I Took Up Smoking


Well Known Member
I have finished installing the Smoke-System Helper. First off thanks to Craig Taylor and Marvin Holmsley for their help. The install was straight forward, not difficult, and no surprises but it does take a little time. Actually just the kind of project I enjoy at this time of year.

I have often wanted a smoke system but several things always kept me from installing one.

1) I didn?t want to give up baggage space.
2) My CG is already aft due to the WW prop.
3) I wanted to be able to remove the system quickly and easily.
4) I didn?t want to pay big bucks for the oil.
5) I didn?t want lots of oil on the belly.
6) If I wanted to get rid of the system I didn?t want to permanently scar the plane.

Marvin and his Smoke-System Helper provided everything I needed to eliminate or reduce my objections to an acceptable level. Here is how I did it.

1)Marvin?s tank takes up very little space in baggage area.
2)The CG moves aft only a little (see details below)
3)The tank takes 2 minutes to remove and the pump another 30 seconds. With quick disconnect fittings on the tank and pump along with 1 spacer instead of 4 washers on each side and latch pins instead of nuts on the mounting bolts.
4)Marvin recommends used ATF which I have available to me.
5)With 2 nozzles mounted forward on cyl # 1 & 3 I am hopeful that the mess should be reduced.
6)Installation was done so that the entire system can be removed with no unsightly blemishes.
With the system installed but no oil my empty CG went from 80.94 to 81.25 and 82.19 with full oil.
My normal flight condition with Pilot, Passenger and Full Fuel went from 84.80 to 85.45.
Obviously adding baggage and burning off fuel moves CG aft but it is all manageable within my comfort range.

I made a simple sight gauge for the side of the tank which I am very happy with. The only thing I have left to do is paint the tank and the project will be complete.

Nice Smoke System

I had a chance to look at John's install last Saturday. If I were to put a smoke system in a side by side RV this would be my choice. Nice and simple and VERY easy to remove with almost no obstruction in any part of the airplane.

One very nice feature John added was the sight tube as seen in his pics. Makes it super easy when filling or just verifying oil level prior to departure.

No affiliation with the maker of the kit other than he seems like a super guy and John had nothing but pleasant comments about the experience, which is good enough for me. Maybe I need one of these after all :D

Any pics on how you got the oil line fed thru the spar?

All my holes are full of wires!
Sorry Brian. I just deleted all of those today since they didn't turn out all that good. Marvin supplies a high quality hose with the kit but I used a thinner wall, more flexible urethane hose compatible with fuel and oil. It was inexpensive and purchased from US Plastics where the quick connect-no drip fittings came from. The fittings are only don't drip after they fluid between the connections leaks out so you do need to catch a very small amount but they are cheap and handy if you plan to remove the tank from time to time. I ran the hose thru the floor board then forward where it makes a 90 and goes thru 2 ribs then forward under the aileron controls(because I already had wires going thru the spar on the outboard bay I used the bay next to the outboard bay) and thru the spar then makes another 90 and goes over to the floorboard and tucked under the lower longeron where it is totally hidden and runs forward to the fuel tank vent and follows it up where it makes a 90 over to the firewall bulkhead fitting. I used 3/4" snap bushings 5 places the hose went thru metal(2 on the spar, 2 on floor ribs, 1 on floor) It was very easy to get the hose from the pump to the firewall and I will try to get a few pictures for you.
Nice work John, that pump install is slick...I didn't even consider that location when I did mine but I sure do like it.
Thanks Ron. I'm very happy with the set up. Brian, here are a couple of pictures showing the line going forward of the spar. Like you my holes were already filled so I drilled another 3/4" hole for the hose.



More of a question than a reply.
Other than drilling another hole in the spar (I'd rather not) how have those with tanks behind the passenger seat routed their oil line to the firewall? I'm installing the same system as John and don't like the look of the black hose going over the spar section before it goes down thru the gear leg support.

Hey John,
Great looking setup.
Do you remember the type of tubing you ordered? US Plastics have quite a few to choose from and a few that look like they would fit the bill.
What is the white thing just upstream of the valve?
Thanks Mike. I am very happy with my set up. The white things are quick disconnect fittings so I can pull the tank or pump within 2 minutes and only get a few drops of fluid. Several have asked about the line and fittings and I always have to look up the specific #s so I will check that for you tomorrow
US Plastics

Mike, here are the item #s for the two lines I used. I ordered 20' of the 3/8 and 10' of the 1/4 for the sight gauge. It doesn't take that much 1/4" but I knew I would be cutting it off to paint the tank.

suprthane tubng ether bse 3/8x9/16x3/32
3/8" ID x 9/16" OD x 3/32" Wall Superthane? Ether Based Tubing

Superthane? Tubing
1/4" ID x 3/8" OD x 1/16" Wall Superthane? Ether Based Tubing

Let me know if I can be of further help.
Great job as always, John!

I have seen your other work up close so I know the quality you put in your planes!
aloha John do you have the part # for the quick disconnects you used?
I like your setup and want to do the same in my -7
Here's my smoke-system-helper setup

A lot of requests as to what QC John used. I asked him myself a while back too. I do not know which John used but followed suite with purchases of hose and QC from US Plastic Corp (USP).

I used the same hose as he did:

10 ft of 3/8” ID x 9/16” OD x 3/32” wall Superthane tubing #56509

The connectors are valved meaning spring loaded to close when disconnected. Here’s what I bought for connecters:

(3) 3/8” ID APC inline body w Shutoff (valved) #064651

(2) 1/4“ NPT APC pipe thread insert with 3/8” barb with shutoff (valved) #064654

(1) 3/8” ID APC elbow insert with 3/8” hose barb with shutoff (valved) #064669

PXL_20210717_153247137.jpg 20210717_153513814.jpg 20210717_153652022.jpg 20210717_153743670.jpg 20210717_181742646.jpg 20210717_181845092.jpg 20210717_182408274.jpg

Hope this helps other down going down the smoke path.
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