The International Cessna^® 170 Association

Hey guys,

I am trying to rebuild my tailspring. I ordered the L-19 spring assy. from Univair, but they don't carry the attachment bushings and blocks. Van Bortel said they are no longer available. What do I do now?

Any help appreciated,
Ryan

Why did you want an L-19 spring? It'll have a different thickness and give you installation issues.
Meanwhile, I've sent you a PM where you can get the parts you need. Check your messages Inbox.

Ryan

I tried one, but the positive camber was too great. It worked great for backing into the hanger, but I really had to lift the tail to spin it around.

I changed my order today, luckily it hadn't shipped from Univair. I thought I had seen on here somewhere were the L-19 spring was just heavier duty and might last longer, especially with my landings.

Thanks for your help,
Ryan

The L-19 sprint is thicker and that is how you can tell when you see one installed on a 170. I never noticed they had a different arc on the 170's I've seen them on. As it is thicker the spring stack is also thicker and probably won't fit into the mount as nicely but I've seen it done so it must be possible.

I replaced my stock tailwheel mainspring with one for an L-19. It is stiffer than the stock one, and is maybe 1/32nd inch thicker. There were NO installation issues, and there have been NO subsequent operational issues.

Air Repair Inc (662-846-0228) has all the parts-- U-brackets, etc.

There's a lot of myths about "problems" using an L-19 mainspring. Air Repair sells tons of these to the C-170 community, per its parts manager.

This subject is a bit more complicated than can be completely explained here, but there ARE issues when installing some L-19 parts (like tailwheel mainsprings) on C-170 tailwheel brackets.
The early 170 steel brackets have thickness problems and the later C-170 brackets will crack the upper plate and the sides at the radius due to the stiffer springs. Then the owner has a major repair to replace the tailwheel bracket. (L-19 brackets accommodate the thicker spring better than the stock C-170 brackets due to dimensional difference at the spring-bed.)

I guess I didn't fully understand , the issues, with these tail leaf springs, I read that the main leaf springs should be changed ,every 500 -600 hrs , as a preventitive maintenance item. I also "thought " the L-19 spring was inter changable , with our 170B tail spring assy.

I rebuilt my tail cone / bracket asy , and bought the full kit from air repair , to change my bracket assy , from the old style to the newer style
( large mouth ) style. So I also bought a L-19, main spring , it was very difficult to install, and now I see that the bottom curve makes the angle at the tailwheel incorrect ? This seems to result in making the aircraft , as previously stated, "very difficult to push / steer by hand , on the ground , except when pushing backwards "

So should I go back the the orginal spring , ( not as thick ? ) . My recent research show from my parts book pn 0542106 , the diagram looks like there a slight bend , at the end, which is what theL-19 spring has. I see the 170A has the same part number 0542106 , BUT the diagram shows a straight looking spring at the bottom end. When I looked at my photos I see that is what was on my plane Ser 20292 originally.

Ok, so the $64,000 is ,....which spring is the straight one ? and is that what I should use ? And if so how can I find the correct part using the 0542106 part number ?


Thanks John

PN 0542106, spring, main, is available from Spruce or Univair. It has two bends.

Ok part number 0542106, if you look at the 170a parts book ,
you will see it spring looks straight at the bottom ....?

The spring which came on the plane was basically straight ?
Is there any source for these staright springs ? Or will the springs from Spruce , Univair work OK ? and correct the scott tailwheel angle ?


Thanks John

The spring which came on the airplane was not straight. Sounds like you hd an incorrect spring.

I had the same questions once. In looking at the drawing in the IPC it does look like the spring is supposed to be straight where it attaches to the t/w assembly. This picture (and the fact that my old tail spring only had one bend) drove me nuts and I pestered George with similar questions. The end result is the picture in the IPC is wrong (not to mention my old tailspring). The tailspring, as George said, DOES have two bends - one where it exits the bracket and one where it attaches to the t/w assembly.

Buy the standard tailspring and you'll be fine.

Ok , thanks so much for the reply and the clarification !
I just can't seem to understand the differances and the same part
number in the 170A book showing no , ( or very small ) bend at the end ,
and the 170B parts book showing more of a bend.

Thanks John

I should have probably found this thread earlier, but here goes:
I too, installed an L-19 tailwheel mtg bracket from Air Repair, and asked them to send the correct new tailwheel spring assy. As mentioned previously in this thread, there is indeed a difference in the bend of the main spring at the tailwheel assy attach end, which leads me to believe I should send it back. Some have said many use this, and some have said it changes the ground handling. In defense of Air Repair there are 2 main springs listed in their IPC. I did tell them that this was for a 170A. Not sure what to do here, it fits and is stronger, though the angle is dramatically different.

Rick

Further investigating shows that the Air Repair L-19 IPC has the 0642101 through 104 springs they sent, for a different tailwheel mtg bracket than what I told them I had. The other set which is 0642157 through160 ,but i am still not sure that it would have the correct or different angle.