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Re: Just thought I would post up some info on my L 4

Thu Dec 09, 2010 8:24 pm

Cleveland brakes for J-3s and L-4s should be avoided if at all possible. They are entirely too effective, leading to nose strikes. One lad here locally flipped his Cub right over onto its back with too much brake application. These aircraft are flown with planning, not brakes and power.

If expander tubes and other Goodyear brake parts become impossible to find, I would consider a new set of Grove disc brakes. The original wheels and tire profiles can be retained, as well as the low pressure Bendix heel brake assemblies.

Re: Just thought I would post up some info on my L 4

Thu Dec 09, 2010 10:04 pm

Expander tubes have been short for a long time. I remember that as we converted our cubs to clevelands, there was literally a waiting list for the tubes and other brake parts. By selling those, it took a good dent off the price of the clevelands. Like I mentioned in my post earlier, the disk brakes are just too much for the stock cubs. I highly recommend to keep tabs on your welds around the axle tubes on whatever the clevelands are installed on. Like I said before. I found cracks on the gear of two airplanes within a years time that I worked there. I had returned to GA maintenance 2 yrs ago and tho we normally dont see the older airplanes at where I worked, a long time family friend brought her restored champ to us for her annual. Well exp paid off when I found a crack at a weld. All the mechanics that I worked with said that they never would have seen it.

Re: Just thought I would post up some info on my L 4

Thu Dec 09, 2010 10:07 pm

tsmgguy wrote:Cleveland brakes for J-3s and L-4s should be avoided if at all possible. They are entirely too effective, leading to nose strikes. One lad here locally flipped his Cub right over onto its back with too much brake application. These aircraft are flown with planning, not brakes and power.

If expander tubes and other Goodyear brake parts become impossible to find, I would consider a new set of Grove disc brakes. The original wheels and tire profiles can be retained, as well as the low pressure Bendix heel brake assemblies.


The heel brake assy's are still retained on cleveland conversions. I am suprised that a company like desser would not make replacement expander tubes. I love seeing stock looking cubs......those clevelands stick out like a sore thumb.

Re: Just thought I would post up some info on my L 4

Fri Dec 10, 2010 5:52 pm

THIS is how you should be flying your L-4:


http://www.youtube.com/watch?v=u9E_vQNxdzM

Re: Just thought I would post up some info on my L 4

Sat Dec 11, 2010 10:58 am

N3Njeff wrote: Like I mentioned in my post earlier, the disk brakes are just too much for the stock cubs. I highly recommend to keep tabs on your welds around the axle tubes on whatever the clevelands are installed on. Like I said before. I found cracks on the gear of two airplanes within a years time that I worked there. I had returned to GA maintenance 2 yrs ago and tho we normally dont see the older airplanes at where I worked, a long time family friend brought her restored champ to us for her annual. Well exp paid off when I found a crack at a weld. All the mechanics that I worked with said that they never would have seen it.


For these reasons, I recommend that some serious consideration be given to replacing some of those old componants with new FAA/PMA items including the gear and cabane struts, engine mount, lift struts, and complete exhaust system. Some of these aircraft are pushing 75 years old. Airborne is a bad place to find out about hairline cracks in vital componants.

43-29080 has new Univair hydro-formed stainless steel exhaust stacks. They look like original, even to the point of turning a pleasing heated bronze color with use. No exhaust leaks, and so no worries about breathing lead fumes. No corroson, either.

It's hard to say for certain without a close up inspection, but the first photo of Russ' aircraft would seem to show exhaust discoloration behind the cowl just aft of the right stack which might be evidence of a large exhaust leak at the junction of the stack and muffler. You want to fix this fast, if it's in fact present.

Re: Just thought I would post up some info on my L 4

Sat Dec 18, 2010 5:20 pm

tsmgguy wrote:
N3Njeff wrote: Like I mentioned in my post earlier, the disk brakes are just too much for the stock cubs. I highly recommend to keep tabs on your welds around the axle tubes on whatever the clevelands are installed on. Like I said before. I found cracks on the gear of two airplanes within a years time that I worked there. I had returned to GA maintenance 2 yrs ago and tho we normally dont see the older airplanes at where I worked, a long time family friend brought her restored champ to us for her annual. Well exp paid off when I found a crack at a weld. All the mechanics that I worked with said that they never would have seen it.


For these reasons, I recommend that some serious consideration be given to replacing some of those old componants with new FAA/PMA items including the gear and cabane struts, engine mount, lift struts, and complete exhaust system. Some of these aircraft are pushing 75 years old. Airborne is a bad place to find out about hairline cracks in vital componants.

43-29080 has new Univair hydro-formed stainless steel exhaust stacks. They look like original, even to the point of turning a pleasing heated bronze color with use. No exhaust leaks, and so no worries about breathing lead fumes. No corroson, either.

It's hard to say for certain without a close up inspection, but the first photo of Russ' aircraft would seem to show exhaust discoloration behind the cowl just aft of the right stack which might be evidence of a large exhaust leak at the junction of the stack and muffler. You want to fix this fast, if it's in fact present.


Thats a good catch. It did indeed have an exhaust leak on the right side as you predicted. It has been repaired but the exhaust system is a patchwork of old fixes and I plan to replace it all this spring. Interesting they replaced almost every other major component in the restoration including a major overhaul and then kept the nasty old exhaust system.

Re: Just thought I would post up some info on my L 4

Mon Dec 20, 2010 4:31 pm

Had exactly the same problem! Too many old componants with too much wear. Could not get the old stacks to seal to the muffler regardless of how much tape and putty I tried. An active high temperature exhaust leak and continuing to breath lead fumes were not options.

Rather than try replacing componants piecemeal, I decided to replace everything with new.

I bought everything that I needed from Univair and can't recommend their componants highly enough. Quality is excellent. Most everything on Univair's J-3 exhaust system is stainless steel. It's all FAA/PMA, fits perfectly, and bolts right up. Everything firewall forward (including the firewall) on my L-4 is new from Univair: boot, upper and lower cowls, engine mount, and the complete exhaust system. Also (as mentioned above) the landing gear, cabane, lift and jury struts, and brake dust shields.

Particularly impressive are the landing gear struts. They are beautifully made and the original wheel and brake componants bolted right on with no "persuading". The gear strut wheel axles also have perfect camber and caster, so the aircraft tracks perfectly on the ground and the tires are not wearing abnormally.

Again the warning about the same componants from Wag Aero. They're not FAA/PMA approved, and so can only be used on experimental aircraft. Also, they are heavy, poorly made, and are generally not compatible with original Piper componants.

Re: Just thought I would post up some info on my L 4

Mon Dec 20, 2010 9:00 pm

I will agree with the Wag-aero crap. We got a batch of parts from a cub project that was not finnished. So they told me to start putting it together and I spent a LONG time trying to get the tank up front. The bastard would not fit no matter what I did. Well we found out that it was a Wag Aero tank and its a bit bigger in size than a J-3 tank. The J-3 has two lower cross tubes in the frame that help support the lower firewall cross tube. Well on the J3, one tube is made to be removed, well on the Wag Aero Cubby, BOTH come out. So you may use a J-3 tank in a Cubby but not the other way around.

I do remember a boot cowl coming from Univair that did not fit quite right and we needed to do some modifications but the bulk of there stuff is GREAT!!!

Definate biggie is the bigger forks on the liftstruts. Most of our cubs had the "bradley" straps and as I was winding my days down, we started getting the new lift struts. Ironically when I was dating my wife, I brought her to the house and was cooking lunch on the grill on the back porch. She and I watched a J-4 start his take off and just as he broke ground, the left front strut fell off the fuselage bracket and dragged in the grass. The wing instantly twisted and dragged the cub back to the ground and basically ground looped off the side of the runway and not even hitting the prop!!!!
I told my wife, you just witnessed TWO people who no longer have a seat cushion or clean shorts and the TWO luckiest people alive and should go buy a lottery ticket !!! I explained what almost happened and that it definatly would have been fatal.
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