The International Cessna 170 Association

UPS delivered two boxes from Aircraft Specialties this afternoon. The cam and crank were inside. They look like new. The crank was still within original specs and the cam got re-ground. I was surprised how much the parts were to re-bush the counterweights. They ended up being more than the labor.



Here's the business end after it was rebuilt and coated.


Counterweights


Everyone always wants to know how much it costs to overhaul an engine. So I am going to post the costs for mine. Here was the bill for a crank and cam from AS. Notice the cost of those bushings! Turn around time was about two weeks.

Looks to me like they have 8 extra 530863 bushings on that invoice......

If you want to plug the muffler to pressure test, go to a local hardware store or plumbing supply house with your muffler in hand and ask for Econo-Plugs. They are basically a tapered solid rubber plug with a washer on each end and a bolt that runs thru the center and a wing nut on one end. Put the Econo-Plug in the pipe and tighten the wing nut. Will expand and seal the pipe.

Kurt Aichele wrote:If you want to plug the muffler to pressure test, go to a local hardware store or plumbing supply house with your muffler in hand and ask for Econo-Plugs. They are basically a tapered solid rubber plug with a washer on each end and a bolt that runs thru the center and a wing nut on one end. Put the Econo-Plug in the pipe and tighten the wing nut. Will expand and seal the pipe.

+1

Kurt Aichele wrote:If you want to plug the muffler to pressure test, go to a local hardware store or plumbing supply house with your muffler in hand and ask for Econo-Plugs. They are basically a tapered solid rubber plug with a washer on each end and a bolt that runs thru the center and a wing nut on one end. Put the Econo-Plug in the pipe and tighten the wing nut. Will expand and seal the pipe.

+1

sfarringer wrote:Looks to me like they have 8 extra 530863 bushings on that invoice......

Yep. There should only be Two for the complete assy.

<edit> Perhaps it's a typo (and price mistake due to the typo), maybe the secy meant 530868, plate, crankshaft damper counterweight pin. There are 8 of those.

gahorn wrote:

sfarringer wrote:Looks to me like they have 8 extra 530863 bushings on that invoice......

Yep. There should only be Two for the complete assy.

Damn! That catch in itself could make the 170 membership fee pay for itself!

Check out page 10 of the IPC for the engine:

http://cessna170.org/forums/viewtopic.php?f=29&t=13249

George, So I am really confused on the number of bushings now Is there a misprint in the IPC? Or is it possible these have been superseded with different counterweights?

I called AS and talked to the shop foreman. He said it the invoice was correct.

Looking at the IPC, are the quantities correct?

Each counterweight should have four bushings for a total of 8. Correct?
Each crank ear should have two for a total of four. Correct?

There's bushings in each bore if that helps.

nippaero wrote:George, So I am really confused on the number of bushings now Is there a misprint in the IPC? Or is it possible these have been superseded with different counterweights?

I called AS and talked to the shop foreman. He said it the invoice was correct.

Looking at the IPC, are the quantities correct?

Each counterweight should have four bushings for a total of 8. Correct?
Each crank ear should have two for a total of four. Correct?

Look at fig 4 on pg 10. Count 'em yourself. TCM counted them on pg 11. While I'm not current as an engine assemblyman, it looks to me like they've either overcharged for the bushings or typoe'd the pn's.

So we can all look at the IPC and count.
There are 8 bushings total.

2- 530863
2- 531015
4- 530866
8 thingies

Something doesn't add up.

Bruce Fenstermacher wrote:So we can all look at the IPC and count.

Screen Shot 2016-12-24 at 7.27.47 PM.png

There are 8 bushings total.

2- 530863
2- 531015
4- 530866
8 thingies

Something doesn't add up.

Plus Qty 4 531016 bushings, for a total of 12.

There's bushings in each bore if that helps.

Sorry I guess that didn't work, too good A? (eh?).

2- 530863
2- 531015
4- 530866
8 thingies
+4 doohickeys (531016)
12- whatchamacallits

A.S. is listing 20 bushings