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Carb issue.. maybe?

The same fuel in your storage tank is the same fuel in the airplane is the same fuel in storage at your camp and it's the same blue fuel dripping on the floor? Does all your fuel came from the same vendor? Since you got the airplane? Maybe the fuel itself doesn't like the cold? You have changed or inspected or ruled out or double checked everything else the collective brain could come up with. Priming, ignition, timing, carburetion, compression. Could it be the fuel itself after all? Is it worth trying a few gallons of fresh fuel from a different supplier? jrh
 
Thanks.. yes same fuel.. same supplier for MANY years and what I have currently isn't very fresh for certain, but at least came from sealed jugs in camp that I filled before a lost a fair amount in my big tank from evaporation.

I'll have to go out to the airport and get a few fresh jugs. Can't remember if I used the 100LL to do Glenn's squirt in the cylinder test or car gas. I should try that again with some car gas and see if it fires.

Still worried about my #4 cylinder.. but maybe it was the heat that let the fuel fire and not rings? But I think I'm still going to have to pull that jug when it gets warmer. Be a few days before I can get the other left mag to try out..
 
irishfield said:
Still worried about my #4 cylinder.. but maybe it was the heat that let the fuel fire and not rings? But I think I'm still going to have to pull that jug when it gets warmer. Be a few days before I can get the other left mag to try out..
Click to expand...
Wayne,
I would be happier with a cylinder that produced 75 plus, but I don't see that being your issue. It just about has to be that stinkin' mag. Even if the compression was a contributing factor(which I doubt) it should still fire on three cylinders. If it runs good under power its not the gas. It sounds like that mag is a bit of a pain to R&R. Wish I could help !
P.S. with regard to the #4 compression. as long as its 70 or better I would put a few flying hours on it and check again before giving it much more thought (or yourself any more ulcers). The rings are probably walking and you just caught them in the same neighborhood.
 
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Well N86250... I don't know whether to :onfire: or :drinking:! Well I already started #2....

I have always run 100LL and believed in the "it never goes bad" theory, although what I've been draining out of the gascolator is a heavier blue than usual.

Here's trying to light some from the gascolator:

https://www.facebook.com/video.php?v=813836182034861&l=1270156394202279245

Here's car gas at the same temp:

https://www.facebook.com/video.php?v=813850115366801&l=1563615317542461431

Here's the bucket from under the intake box:

https://www.facebook.com/video.php?v=813852802033199&l=1160221996868328104

Here's the last fuel out of the wings... suggesting this stuff separated / settled over the time the airplane sat in the hangar. Fired just like the car gas.

https://www.facebook.com/video.php?v=813859468699199&l=4112023416343216885

I called and there's nobody out at the airport to get new fuel. I pulled ONE plug and shot some car gas in there... and it FIRED on about 3 blades, probably the count to spark in that cylinder! It then came on line slowly missing and then again smoothed right out and purred on that old 100LL!

Oh well, lots of other stuff to work on, now that I have the mags good for another 500 hours. Pulled the prop and my seal is leaking between it and case, not it and shaft. Currently has a one piece 10-13792 in place. I have a split SL76940 in hand. Should I order a one piece vs using this spit?.. I have to order the sealant anyhow. I also had some charging voltage spikes coming home in the fall... thought it was my belt.. my bearings are toast in the alternator. At least I have an identical spare here that a customer gave me 12 years ago! I'll have her ready for spring.. lol.. hell I gotta laugh !

Apologies to many for not following your earlier thoughts! Frenchy I think pointed out the lack of fuel volatility issue earlier on and Glenn I'm not sure how to get your cheese back to you, Leah already ate half of it!! :smile: Guess you'll just have to visit and we'll add some wine to it!

At least I gave you all something to do for 6 weeks in the winter! Just wish I had of spent it ski flying, with some perfect conditions up here. Oh well, float season is around the corner. Hope I can get to enjoy some of that with the family!
 
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another thought....

do you actually have REAL primers that atomize the shots of primer fuel???

or did someone throw in normal fittings at install....?? (seen it before..)
 
Already been there Mike.. back on page 2. I wasn't sure so I pulled the fittings out. Had 3 wands and one straight "spray" style. None were just open fittings. I swapped in a 4th wand, cleaned them all, flow tested and reinstalled.

Wish I had of videoed the very first time I dumped the 100LL from the gascolator on the man doors cement sill. I couldn't make it burn period with the lighter.
 
At many days below -30C Doug... I can't see it. My quick drains would be frozen.. gascolator drain for sure. It was 21 F when I made those videos.

I think it's just old fuel (well I know it's 2 years old, since that's the last time I filled my 500 gallon tank - currently empty)... and it's had since September to sit in my wing tanks and somewhat separate sending the less volatile stuff down to the gascolator. As shown the last few gallons out of the wings was lighter in "blue" colour and burnt just like car gas.

Hoping my one piece seal gets here tomorrow... nobody chimed in on that whether I should go split or one piece. I'll have both here and have done a one piece before so not scared of it, just the split would be easier. Once I have that curing into place I'll replace my alternator and then get the nose bowl and prop back into place. Also giving thought to cutting my nose bowl in half and making that a two piece while I have the easy opportunity.

There's not any cold in the forecast until late next week, so by then I should be ready to run it again and will have got some fresh fuel from the airport to do so.
 
irishfield said:
nobody chimed in on that whether I should go split or one piece.
Click to expand...

I prefer the one piece seal over the split seal, but have used both. IMHO, it's easier to get the spring into the solid seal than it is with the split seal, but neither is too difficult.

-Cub Builder
 
Thanks guys... I couldn't win the lottery if there was one ticket sold and it was to me.

Was moving some stuff around in the hangar and for some reason looked at my crank flange on the way by. Sure wish I'd noticed that +050 stamped on the right case half at the nose! Had a closer look at the existing seal and indeed.. P50! Guess I'm not doing that job tomorrow.... %*($*%
 
Ive used duct tape over the prop bushings over the crank flange trimmed up with a razor blade to try and help out with the ocraps.
 
Thanks Doug.. last time I did it I took the (I believe) Steve Pierce approach, with a zip lock bag over the flange and it seem to work well.

Now I have to find a place to order a P50 seal.. and pay shipping again. Oh well, I'm sure I'll find a day in the future for the regular 13792 that will be here tomorrow and the split I have in hand is no good for me either.
 
Anyone have some defib paddles handy??? I paid $20.85cdn yesterday (and $14 courier) for an LW-13792 seal and some pliobond to be here tomorrow.

Now that I realized I need a LW-13792-P50 seal... I just went to order one and it's TWO HUNDRED AND FIFTY THREE dollars !! :Gwhoa:

As noted I'm not leaking at the crankshaft to seal, but at case to seal..... so tomorrow is going to be a scotchbrite and PRC day around here. No gd way I'm paying that kind of money for a rubber seal unless it blows out!
 
To stretch one of them and ruin it would suck. They are cheaper at some places, but not enough. Do they make a 50 in the split type?
 
Yah.. I found the cheapest was $160 US.. so still $200 Cdn. Yes there is a split P50 LW-11997-P50... $293.59 US $'s from Aircraft Specialties!
 
Yep... found that a few days ago... and it didn't even clue me in to look a little better at the part number on the seal. Well maybe it did subliminally, as I'm sure glad I noticed someone was thoughtful enough to stamp my case snout with the +050 before I popped the seal !
 
Ok I have to ask.
Could the leaking seal be caused by increased case pressures due to whatever is causing the starting issue? Just asking it would suck to fix the leak and have it happen again.


Sent from my iPad using Tapatalk HD
 
Was one of my thoughts further back $hotgun, before I concluded it's a fuel volatile issue... or lack there of ...to why it won't start. Now the ice I had in the engine.. a possibility the return gallery could have been clogged at the seal, but I started thinking about it some more and I've always has a bit of oil by the starter and case bolts and figure it has just progressed to be a bit worse.

Now that I pulled the prop and bowl and know it is definitely leaking between case and seal vs seal and crank shaft, I am comfortable that it's just a leak that has gotten worse and not a pressure thing. I think pressure would have had it blow by the lip seal, not the bonding glue.
 
irishfield said:
Now that I pulled the prop and bowl and know it is definitely leaking between case and seal vs seal and crank shaft,
Click to expand...

why replace the seal then?? just clean outer edge and re-glue it in....

I've had bad luck putting new ones in(don't do it enough..), so they gotta be leaking bad on shaft before i try....
 
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Was going to scotchbite and PRC but sounds like a better idea if you have a suggestion on how to "pop it" out without damaging it.
 
Well it turned out that was a dumb question... I decided to clean the seal to case grove a bit with a dental pick today and noticed things moved. One flip after that and it came out with my finger nails. No glue what so ever holding it in, the only place I found glue / sealant in any quantity was using a hooked dental pick and fished it out of the seal spring area. Explains the years of a minor leak I guess and suddenly worse. Surprised it lasted this long. Got my Pilobond (and the std size seal I don't need) off the courier at 3:30.. but have too many other things tonight and tomorrow going on. Will build a tent to heat on Thursday and get this cleaned up and glued back in. Maybe I can take Jen for a ski flight next week yet! :-)

https://www.facebook.com/video.php?v=815525481865931&l=905888118318888285

crankseal.webp
 

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irishfield said:
Well it turned out that was a dumb question... I decided to clean the seal to case grove a bit with a dental pick today and noticed things moved. One flip after that and it came out with my finger nails. No glue what so ever holding it in, the only place I found glue / sealant in any quantity was using a hooked dental pick and fished it out of the seal spring area. Explains the years of a minor leak I guess and suddenly worse. Surprised it lasted this long. Got my Pilobond (and the std size seal I don't need) off the courier at 3:30.. but have too many other things tonight and tomorrow going on. Will build a tent to heat on Thursday and get this cleaned up and glued back in. Maybe I can take Jen for a ski flight next week yet! :-)

https://www.facebook.com/video.php?v=815525481865931&l=905888118318888285

View attachment 19315
Click to expand...

the good news is you don't have any built up crankcase pressure or that seal would have popped out long ago.
 
YEP! Feeling better every time I do more work on this thing ! LOL Makes me get closer to the fact it was just the fuel...

Nothing holding it in but the OD lip.
 
Nope.. it's a -P50, to match the +.050 I found stamped on the case. Hope they didn't over bore the case at ECI or something.

Either way, it's gonna get cleaned and a good coat of Pilobond on both parts and then put back together.

Guess I could measure it first for peace of mine... yah I'll do that Glenn ! ;)
 
Heck if it worked without sealant it should work like a charm with it. starting fluid makes a good degreaser.

Glenn
 
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