Fuel Strainer Bowl Clamp Assembly

[BobPicker]

PA-24/250
During my annual that is nearing completion as I write this, I had a major problem with the clamp assembly that holds the fuel strainer bowl to the fuel selector body. The 10-24 fillister screw that squeezes the clamp had the screw head fail and snap off. Just wore out due to age and years of tightening to create the clamping forces to seal the selector-screen-bowl interface. Therefore, I AM GROUNDED! I like many of us do in a crisis, I immediately contacted WEBCO for assistance. They do NOT stock any parts for the clamp assembly! Plus they have no sources for any replacement clamps. OUCH!!!

I have started researching various sources to find a replacement clamp. This part, I feel, is a 50+ year old version of what is called a V-band clamps today. These types of clamps are available from a number of current manufacturers in hundreds of configuations. I have already sent a request for assistance to Clampco with all the measurements and photos.

My mechanic tried to modify an AN-3 bolt of sufficient length to replace the broken screw, but was not pleased with the lash up and will not sign off the configuration change. Besides he could not get the leakage from the mating surface interface to stop with the old screen/gasket and we ran into difficulty getting a new screen and gasket that is correct size (minor manufacturing problem with supplier). He has also put out inquiries to his sources for parts with no success so far.

If any one has had to replace their clamp due to age/wear and knows of a source of our parts let me know. OR If you have converted successfully to another type of clamping mechanism please send me the manufacturer name and the part number. I am in a no-go situation without this clamp. Any help/ideas is welcome. If I get some leads on a replacement clamp I will let everyone know. The last hurtle will be the process to approve an alternate clamp for use in this application.

[Fred]

You could install a STC PMA replacement from Aircraft Spruce
PA-24 ( S/N 24-1 thru 24-2298) 1A15 SA3-00
Gascolator STC - PMA - 1/4 NPT 3/8" Line 3 oz. Fittings and drain plugs are not included SA3-00 05-12468 $272.95
These FAA-approved gascolators are CNC-machined out of 6061 aluminum for longer use and feature anodized "O" ring seals for improved sealing capabilities and a bayonet tab locked bowl system. No more wire bales popping out of the cover or stripped thumb wheels or screws. Direct replacement for factory parts. FAA-approved for many Piper, American Champion, Husky, Maule, Taylorcraft, Dynac and Cessna aircraft.

Fits in existing Piper mounting brackets.

Great for homebuilders also.

All fittings and drain plugs are for display purposes only and are not included with gascolator purchases.

8130 Form are not available for these gascolators.
Fred

[BobPicker]

Fred,

Thanks for the info, but I am sorry to say this will not work on my Comanche 250 s/n 3497. I have a 4-tank fuel selector that is mounted on the floor with integral strainer screen and sump. I need a 5 position selector with sump (2 Aux tanks, 2 Main tanks and OFF position).

[Andrew Foster]

Fred
Had the same issue on our 250. We replaced the screw with a similar stainless steel size and length , using two nuts on the end. As a extra precaution I safety wire the assembly together after checking for leaks. The screen/gasket combo came from Webco.
Getting the clamp on correct so it doesn't leak sometimes can be a challenge.
Andrew

[BobPicker]

Thought I would post what has transpired trying to repair, replace, fix my strainer screen and clamp assembly issues. First, I was able to get a new strainer screen that fit. Seems the supplier had a slight issue with their die for cutting the diameter. They found it had stretched slightly causing the first one sent to be too big. The replacement was perfect.

As for the broken screw that tightens the clamp, I was able to find a 2-1/2 inch Allen-head 10/24 screw at Tacoma Screw Supply. This screw is a high strength screw with a black finish. Our only concern was the length of the threads and that it had no holes for safety wiring. May address the thread length at a later time. First step was a test fit and found it necessary to add a bushing/spacer of about 1/2 inch and a washer under the head to make sure the threads did not bottom out. We then drilled a hole through only one side of the allen-head for safety wire. We installed it and kept slowly tightening the screw until the clamp had enough pressure to cause the new screen/gasket to make the seal. Happy again and test flight accomplished with no issues.