RIPOFF: Fuel Strainer washer & seal kits

SkyKing · #1 08-29-02, 12:47 PM

What a surprise... Chock-up another 'proprietary' interest for high-priced Cessna parts.

Instead of $6.75 for the Cessna fuel strainer kit that Chief Aircraft no longer carries (P/N TKIVT1 - with O-rings that meet M83248/1 specs and manufactured by Viton), it will now cost you $26.95 (or more) for the same items from Cessna!~

I asked the sales rep at Chief what the deal was, and was advised TKI no longer makes the kit. Gee, I wonder why...

One of the gaskets that was included in the Chief Aircraft kit, which fits above the filter, is alone list priced at $13 bucks... what a RIP-OFF.

Does anyone have alternative sources?

As far as I'm able to ascertain, the fuel strainers on the Skymaster are the very same ones that have been used on ALL of the single-engine series since the beginning of time.

SkyKing

GMAs · #2 08-29-02, 12:57 PM

Hey you can go into the parts manual and get the O ring size... and order them by themselves... just make sure they are the viton or what the manufacture specs out... but, they are all common AN parts... that can be gotten thru any supply store... you don't need to go get a "Kit".. unless it is cheeper...

Some other areas that have parts are listed in TAP...

GMAs...

SkyKing · #3 08-29-02, 02:02 PM

GMAs,

Did a Dogpile search for "Viton" -- which is the manufacturer of the O-rings... but before the show can go on, we need to know the axial cross

Guess we'll have to go buy a micrometer to measure the old ones. Has anyone already accomplished the task, so we don't have to re-invent the wheel? At least we know the Mil-spec, which is M83248/1. Not sure about the gasket that goes above the filter, I think that one is cork material??? Haven't taken mine apart yet.

I'm doing the fuel strainers prior to annual because yesterday when I went out to check on the plane, once I got in the hangar there were two blue-stained areas of avgas under the plane on the floor, about 12" diameter and fuel stains down both the FWD and the AFT wheel well areas... safety wires on the bowls were tight BUT the 5/8" nut was loose and could be easily turned more than a FULL TURN and then the safety wire was completely loose! The FWD strainer sealed off after a full turn... it was leaking from the bottom seal, but the AFT strainer is leaking from the top of the plunger where the pull cable attaches, so I suspect the top O-ring. We've had really warm WX since I last flew on August 17th, but it seems the bowls were not installed tightly enough by you know who; no, not me! And yes, I know, the torque is 25-30 lb in. So what this tells me is that the strainer bowls haven't been serviced, even though the logs say they were.

Oh, and guess how much Cessna gets for the S1450-27A7-032 O-rings, of which two are required for each plunger? $7.66 each. Just more corporate welfare!

SkyKing

SkyKing · #4 08-29-02, 02:06 PM

Part of my message didn't make it... I was saying, we'll need to know the axial cross section dimension, the radial cross section dimension, as well as the inside diameter.

SkyKing

SkyKing · #5 08-29-02, 02:30 PM

GMAs... and anyone else tackling the fuel strainer:

You'll find that the O-ring part numbers have all been changed from the ones listed in the parts manual! Here's the new numbers for Figure #120 in the Cessna Illustrated Parts Manual for the 1973-1980 Model 337 Pressurized Series:

NAS1593-111 superceded by M83248/1-111 ... List price: $0.34
NAS1593-138 superceded by M83248/1-138 ... List price: $1.61
NAS1593-010 superceded by M83248/1-010 ... List price: $0.31

Okay, that takes care of Index Items #4, #5 and #16. Now, what about these:

Index Item #8 - P/N 0756009-8 Gasket... List price: $13.00
Index Item #14 - P/N S1450-27A7-032 Washer... List price: $7.66

GMAs, is #14 a rubber or metal washer... and do these need to be replaced when servicing the strainer??? The parts manual calls for two each per plunger. If not, then the only other item needed is #8, the Gasket.

BTW, the Plunger Assembly, P/N 0756010-6 is superceded by P/N 0756010-11 and carries a list price of $109 bucks! And the standpipe, which was the subject of a prior safety notice by GMAS on the old UNO-Skymaster website, P/N 0756011-1 carries a list price of $116. Does anyone else have these available at a more reasonable price???

SkyKing

GMAs · #6 08-29-02, 02:43 PM

Call Sac sky ranch... they have parts for the strainers.. such as O rings... and no the washer does not have to be changed... if it is inspected and found to be in good shape... only the O rings need to be replaced when you take it apart...

the screen and plunger can be gotten at McFarlane 800-544-8594... http://www.mcfarlane-aviation.com/ as well as several others are making them now out of SS which is less corrosive and seems to last longer... but, the original is lighter and stronger for its weight... you and your mechanic have to make that decision...

They have other items that will sub for cessna parts...

As to the replacement of the screen and gasket... under it... we want you to look at the filler pipe... the alu pipe that hangs down thru the brass screen... as we showed on the pictures which were posted on the other web site... if the screen looks clean and clear... then their is no reason to take it apart... the other O rings up in the plunger area... are also common ones... and run about a buck each...

Hope this helps... you all might want to get a few of the larger O rings... and the ones that go under the nut that holds the cup on... those two are the most common ones used... and come in a sealed paper package... but, watch the cure date on them.. nothing over 5 years....

HOpe this helps .. GMAs...

stackj · #7 08-29-02, 05:27 PM

When reinstalling the fuel strainer be sure not to overtighten the link which goes between the plunger and the cable. The link must be able to pivot at the top of the plunger. If it cannot, the cable will put a side load on the plunger when operated and will cause premature failure of the top O-ring.

Don Nieser · #8 09-03-02, 12:51 AM

OK maybe I can help. I have the following new surplus Cessna parts avaliable and I will beat any other's price:
P/N 0756009-7 (filter screen)
P/N 0756011-1 (standpipe)
P/N 0756005-2 interchangeble with 0756006-1 (Top)
P/N S1239-27 (control cable)
Don Nieser
Commodore Aerospace Corp
6221 Commodore Lane
Oklahoma City OK 73162
405-722-4079 phone and FAX
405-503-4686 hangar cell phone

Wayne Pearce · #9 09-03-02, 05:11 PM

I paid $3.50 Australian for the complete kit from Cessna Distributor about 4 weeks ago...........I'm happy

Regards ........... Wayne

GMAs · #10 09-04-02, 07:35 PM

Just finished reading about another plane that went down... why.. because the owner/operator assisted maintance... seems he took the gas strainer appart and with out anyones help put it back in with the old parts... got into the mess of bending up his plane... and now wants to sue the mechanic for not helping him do it right... Hmmmmmm.... seems to me that he took it apart and put it back togeather... all by himself... it it had worked would he have paid the mechanic for the work he did... nope.. so why should the mechanic be responsable for his errors... after all he didn't charge him for it.. ..

But, thats not our intent here.. to find blame over who did what...

INstead we want to look at the strainer again... and take a good look at the gaskets or O rings... here we NEVER...NEVER... EVER.. USE THE SAME old O RINGS... do we... we always put in new ones for the cup and tube... when we pull it to inspect for items in the bottom of the cup...

DO WE HAVE TO PULL THE TUBE... no.. not if the screen looks good and their is no corrosion around the fuel inlet tube where it contacts the brass screen... and yes we can look both inside the inlet tube with a flashlight on the outside... to see if it has holes where it is in contact with the screen... if the fuel system is clean you should not have any rocks or small children stuck in the screen....

SO WHICH O RINGS HAVE TO BE WHAT.... well the big one at the top of the cup.. where it seals and the bottom of the cup where it goes around the drain tube.... are all we need for the inspection time... if their are no stains on anything else... where shafts come thru then we are in good shape and the overhaul of the unit is not needed unless it is over 3 years old...

SO HOW DO YOU PUT THESE GASKETS BACK IN... well more the question how to get them out... here we use a dental pick.. ya if you go to the dentist you might ask him to give you some of the old ones that he is throwing away.... lucky I have a brother who we put through dental school.. who keeps me supplied with all kinds of neet picks... but,....

what if you don't have either... well you can use a piece of dike cut off safety wire.. yep the old 0.032 blood maker... has a real sharp end on it... take the needle nose plyers and make a little hook.. about 1/8 inch long.. press it up into the old O ring and hook it... then remove it... simple huh... well.... for some at least...

Do the same with the small O ring that was under the compression washer which was under the tension nut... and discard them both AFTER you have checked the size against the new ones... is what you want to do... the old ones should be a little bigger in size.. because they expand with the solvents in the avgas... but, they should look about the same...

SO HOW DO WE PUT THE NEW ONES IN.... ahhhhh here is where paying the mechanic is the trick... well it can get frustrating to put the big one in.. only to have it fall out or get trapped when you put the cup back up over the tube (or try to...)

Here is the trick... put oil (engine) like the service manual says... all over the big gasket... stuff it in the land that its supposed to go into...(the oil will cause it to expand a little... so don't have any wrinkles)... or it will leak... then put the cup over the drain tube without the other o ring... or washer... take those oily fingers .. the ones that you lubed the big O ring with.. and lube the drain tube bottom and threads... and now with one hand holding the cup just slightly away from the upper o ring... put the bottom O ring on... and then after you cleared the thread.. (some cover the threads with a piece of real thin heat shrink tubing... with out the heat)...slide it up into the bottom of the cup... and use your thumbnail or some other flat soft object...to force it into the land...and then push the whole thing up so it will go up and lock in place with the bottom O ring holding on if not too much pressure is required... remove the plastic sleave (heat shrink tubing)... and put the compression gasket on making sure the lip goes up on the inside bottom of the cup.... then the nut and thread it up... at this point some mechanics slide the cup around so that they make sure it is not trapped with a twist... if it looks and feels right.. then they tighten up the nut on the drain tube...

OK.. WE GOT HERE....NOW WHAT...
Well we have to torque the nut on the drain tube... so that the cup will seal well up at the top.. while not overtightening it to the point that we strech (lengthen) the drain tube... how much is enough... see service manual for specs.. as cessna made it.. they have the specs for it...

Once tightend... turn on the fuel... have someone grab the drain pull and open it...so that you get rid of the air in the strainer and lines...then stop and check for leaks... and just because you don't see any.. doesn't mean that its not leaking air in... remember they are at the bottom... and any fuel that is drawn thru (suction) will also have a tendency to pull air... and giving you all kinds of symptoms that you don't want... so what we do is on the fwd one.. turn on the boost pump... mixure off... throttle off... run it for a few seconds... and then look for leaking or sweating... as the pump is behind it.. and on the rear... well we pump that one up too.. but, with the throttle and mixture open... so it forces the air thru... listen for the pump to load up... and indicate fuel pressure...and then let it come back down.. looking for wetness...

IF NO WETNESS IS FOUND.... then we get the safety wire out and with a 1/4 tightening turn around the cup twist.. fasten it from the little hole on the mount ear of the strainer... (hint.. put the safety wire on top first... before re-assembly... its easier... smile) to the hole in the nut on the bottom of the drain tube.... put a roll in the safety wire end.. so it doesn't bite you later... and attach the overboard vent line... and again only torque the nut per specs... here we can look in our 43.13... for hydralic line fitting tighteness or check the manufactures spec in the service manual...

ARE WE DONE YET..... NOPE... WE WANT TO CHECK IT A COUPLE OF MORE TIMES FOR SWEATING OR LEAKING... AND THEN AFTER each flight.... for a couple more times.... IF YOU SEE ANY DYE MARKER STAINS... which is in the fuel.. like green or blueish color.... around the cup or top of the strainer... guess what you have to do... yep.. you get to do it all over again... because you have a leak... and a failure somewhere in the unit...

OH AND FOR THE OVER the hill 5 YEAR CLUB...you want to remove the unit... totally when you overhaul it... ya its a bear.. especially the rear one unless you take the rear bottom pan of the back of the plane... all them screws... makes it real easy to get to...however the fwd one....to get the safety wire back on the bolts which hold it on...is really dificult... but, just be patent it does work... and overhaul ALL the O rings...

AND WHAT IF I DON'T.... well ever had that lean engine feeling... on take off... or at altitude the engine keeps quitting... runing hot or just peforming like you have a miss... or bad spark plug... or you smell fuel down between you toes... and wonder what it would be like to have it light up.... I once had a picture that someone took of a plane coming out of the sky... luckly it wasn't a skymaster... that had a fuel leak... and it looked like a roman candle flair.... and when it crashed... looked like a minature nuke... oh and the pilot and his girl friend were wearing parashutes as it was a homebuilt... but, the fabric caught on fire... when it opened... and let them free fall all the way down... something that I don't think would be fun.. and runin your whole day....

SO.... do a good job.. have your mechanic check it out if your not comfortable... and keep checking for leaks on your pre-flight as well as a (ahem...) post flight ..... because if it leaks.. you could be sucking air and we all know that a engine that doesn't have fuel can make you a dead sucker.... but, remember when you hit the boost pump on the fwd eigne it will be putting fuel where you don't want it... and on the rear... well it just grabs more air... so how is your single engine abilities... smile... GMAs... fly safe

GMAs · #11 09-04-02, 07:38 PM

Make sure you use new, current cured parts (O rings).... none of this auto junk... the fuels are different... and it will get you into trouble... if you don't... ONLY AIRCRAFT GRADE PARTS PLEASE... after all they are cheep... for what they do... smile... GMAs

SkyKing · #12 09-04-02, 10:03 PM

GMAs,

Thanks for the 'expanded coverage' on the fuel strainer... my rear strainer unit on our '77 P-model has a slow 'weeping' leak from the top of the plunger so it must be the top O-ring that's gone bad, most likely from heat as the top pivots ok without any sideloads.

So, after removing the bottom nut and the cup and then disconnecting the small cotter pin at the top of the plunger, is there anything else that needs attention?... you didn't cover pulling the tube and it looks like that's the order of business when I get time.

SkyKing

GMAs · #13 09-04-02, 11:28 PM

Well of course the way to do it is outlined in the service manual....but, we have our ways too... smile..

Ok.. your going after the rear strainer... and you need to over haul it... what to do...

FIRST... we need to remove the rear cover off the airframe... yep its so much easier to remove it that way than to fight for hours on end trying to get the safety wire back in... correctly without getting a universal jointed hand...

The cover were after is the center one that is below the engine their are rows of screws (dome heads) that come off each side as well as the back bottom of the outlet ring... once removed the engine is hanging in air... kinda like... and you can get to the rear deck which makes up the wheel well...

SECOND... once their.. you will see the two bolts and their safety wire that hold the gas strainer to the rear bulk head of the wheel well... cut the safety wire.. but, do not remove the bolts as yet...

THIRD... go to the manual gear door extension and open the rear doors... those of you that don't have them... well you get to feel around till you find the gas strainer...

FORTH... shut the gas off to the rear engine if you haven't.. and extingish all open flame or spark making materials as you are going to have some fuel leak out and on the floor... also have a pan and a rag to keep yourself dry... and catch the gas with...

FIFTH.... go to the rear and with can in hand... open the fuel drain for the strainer... should be about a quart of fuel come out.. as it will also drain the lines with the fuel shut off...

SIX... go back under and remove the cotter pin from the plunger... for the pull cable... and then take both of the fuel lines off... again being careful that you don't get fuel on you skin for long... keep lots of ventalation or open air.. and make sure you post a sign keeping all visitors out of the area... so that you don't get a chance for a spark or fire... some mechanics will wait a reasonable time after opening the fuel lines for the residual fuel to evaporate.... but, we find that if you take care and keep things grounded you can proceed on with your operation...

SEVENTH... once the fuel lines and fuel overboard drain is removed and free away from the strainer... go up to the back again.. and remove the two bolts that hold it in... carefuly watching for washers and not letting the strainer drop...

That is the removal process to install.. you do the reverse except for the final is safetying the bolt heads with safety wire...

Ok now for the removal of the cup and other items... which we covered in the previous part... we are down to the top of the housing and the drain pipe and plunger...

Here you will notice that the plunger has a spring keeping it down... pretty stiff one at that... so what we do is go over to the drill box and find a 6 to 8 inch drill bit that will fit into the two holes that make up the drain tube down at the bottom... as it is threaded on to the top housing which also holds the screen in place.. so the tube will come off just below the screen...

Now come the vise or a second person... that can hold a large cresent wrench... and keep tension on the plunger....

So here is what we want to do... we want to make sure that when we put the dirll ALL THE WAY THRU the two holes... it make a kind of T Bar handle... equal distrubution on the drain tube...

But, wait... not as easy as that huh.... their seems to be something in the way... and not allowing the drill to slide through... yep its the plunger... and we don't want to mess it up if we can help it... providing that the thing didn't leak.. we want to keep the rubber tip...(if you mess it up.. its has to be replaced as a complete plunger)... oh what to do...

Well.... we have someone put a piece of safety wire with a loop or another drill thru the holes that are at the top of the plunger... where we took the tab kotter pin and keeper off of... now we will have two T pins... one to pull the plunger up and the other to unscrew the drain tube... wow and you thought two hands were always going to do it... not in this case.. unless you place the housing in a vice.. so that you can have control of the othe two items...

So here we go... to remove the plunger and tube... we pull the plunger up.. way up.. past the two holes in the tube... and while maintaing this position we put the other drill bit thru the holes at the bottom where the plunger use to be... and while not letting go... twist the tube by using the drill bit that just fit inside the holes...

Now if everything is working right you should be able to remove the drain tube... while still maintaing the postion of the plunger... its kinda improtant to do that because if you release your pressure... you will flatten the end of the plunger rubber tip... and render it as junk... they only cost about 60 bucks... so if you have the buck... let go.. otherwise hold on... to it while the drill is in the area of where it comes down thru... so that you don't mess it up...

Once the tube is removed... you can let go of the upper drill or safety wire.. and the plunger and spring will come clear of the housing... that is if some bimbo hasn't bent the two ears on the top of the plunger ... they should be the same outside diamater as the shaft... and not bent outwards...

Once the shaft is clear.. we now have to go after the little O ring at the top of the housing... this one is not user frendly... and doesn't like to come out... or go in... smile... but, with a little picking you can get it to come out... and to put the new one in... lots of engine oil again... however don't use the plunger shaft to push it down... the back of the drill shaft seems to work better so long as its not twisted when it goes in...

Now we trun or attention to the plunger... here we want to use a stone to take off any sharp areas of the split at the top... look at the rubber tip and make sure its not getting that cracked up look... if everything seems OK... and the mechanic is happy... (yes this is a mechanics thing and not a pilot thingiee)... then you can start to put it back togeather... first the plunger and spring... along with its washers... again lots of oil on the shaft where it is going past the new O ring in the top of the housing... and once thru put your small drill thru the holes in the top split part.. to keep it from coming back down...

Now put the new gasket for under the screen... and screen which has been cleaned and checked... along with the inlet alu tube to make sure that its not corroded....

Ok once the gasket and screen are in place... we pull the plunger rod back again and thread the drain tube back on by hand.... then we can release the pressure on the plunger and let it seat on the bottom of the tube for a min... then with a mighty thrust.. we pull the plunger back up out of the way... place the drill thru the two holes and tighten everything up.. making sure that the gasket, screen and plunger are all in position frimly tighten the drain tube....with the t handle made from the drill and the tube...

Remove the drill bit from the tube and slowly release the plunger so it seats down into the tube bottom... past where the drill bit was used to tighten it... it should work smoothly... and all the other pieces should be in place ....

One word about he drain tube inspection.... check the cessna service bull.. or go back and look at the pictures that we posted on the other web site... I think you can still see them... as the tube is made of Mag metal.. it will corrode first... and the threads as well as the small section will and can strech... so pay attention here to the condition of the tube... if too long your cup will not seat properly... and allow gas to get out and air to enter... so we have found.. and no matter how tight you tighten the nut which holds it togeather... you ain't going to stop the leak... it is made for a specific length.. and if it looks bad in the thread area or around the taper section... my advise it to replace...

I would put the rest of the rear strainer back togeather on the bench... all but, the final torque on the nut that holds it togeather and the safety wire.. which I have put thru the top hole and given a couple of twist to....

Take the assembly back down and install.. making sure to use lots of engine oil on any threads and fittings... and follow the directions in the service manual and suggestions that we posted in the other previous on servicing them.. and safetying.... along with re-fueling them back up... and checkig for leaks... and no you can't take the tube off while its in the plane... as you can't get the plunger up high enough with the cable attached... smile... so don't even try....

Simple huh..... maybe we should have one at a meeting so you can see how to take them apart and put them back togeather again... once you see how .. its real simple... just don't let the plunger drop on the drill or try and twist the tube off with it at the bottom... as it will runin the rubber tip... for sure...

Hope this helps.... GMAs....

#14 02-24-03, 09:25 PM

Guess you may know this
McFarlane Aviation have seal kit TFS-1 for a few bucks it includes;

MS29513-138 O'RING
MS29513-010 O'RING
MS29513-111 O'RING
0756009-8 GASKET

We put one in at each 100 hourly.

SkyKing · #15 02-27-03, 05:30 PM

Hi "kswalsh"... I guess you're another "Kevin"...

Yes, we bought the TFS-1 McFarland O-ring kits... the local Cessna dealer charges $6.95 for them and we keep an extra pair on hand.

Everyone would do well to carefully inspect the fuel filter screens in the bowl and have a couple of those on hand too... we found some minute areas in the screen mesh that were breached on our rear unit that necessitated its replacement. Cessna is getting $14.03 for these now. Better buy them now to beat inflation.

SkyKing