Exhaust Risers too long??

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oldtrucksrule
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Exhaust Risers too long??

Post by oldtrucksrule »

Hey y'all, I'm clipping away on this motor. I got the risers ordered but, it looks as though they're too long. Is it possible I ordered the wrong length? I ordered the P/N's I found. Thoughts?
Riser length.jpg
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Bruce Fenstermacher
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Re: Exhaust Risers too long??

Post by Bruce Fenstermacher »

We don't know what parts you ordered. Here is the parts pages.

Your looking for:
4 ea. 0550157-7
2 ea. 0550157-8*

Pipes are the same each side.
Screen Shot 2020-07-30 at 5.53.26 AM.png
Screen Shot 2020-07-30 at 5.53.41 AM.png
*corrected part number
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Bruce Fenstermacher, Past President, TIC170A
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oldtrucksrule
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Re: Exhaust Risers too long??

Post by oldtrucksrule »

Bruce, Those look like the part numbers I ordered. I'll double check, Thanks!
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oldtrucksrule
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Re: Exhaust Risers too long??

Post by oldtrucksrule »

So, the part numbers I have are

2- 0550157-8
4- 0550157-7
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c170b53
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Re: Exhaust Risers too long??

Post by c170b53 »

Ah, judicious use of the speed color :D
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
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oldtrucksrule
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Re: Exhaust Risers too long??

Post by oldtrucksrule »

Thanks, I talked to the builder of the risers and they are going to build new risers custom to my exhaust. Very stand up and easy to rectify the situation.
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Bruce Fenstermacher
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Re: Exhaust Risers too long??

Post by Bruce Fenstermacher »

The big question is, why is your exhaust CUSTOM? It should not be.
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GAHorn
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Re: Exhaust Risers too long??

Post by GAHorn »

It certainly appears those risers do not meet spec. Who made them? Can they confirm they shipped the correct pn’s?
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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cessna170bdriver
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Re: Exhaust Risers too long??

Post by cessna170bdriver »

Looks to me like the flange on the #1/#6 riser wasn’t clocked correctly on the pipe.
Miles

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GAHorn
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Re: Exhaust Risers too long??

Post by GAHorn »

cessna170bdriver wrote:Looks to me like the flange on the #1/#6 riser wasn’t clocked correctly on the pipe.
Even more obvious (it seems to me) is that they are ALL too long for a 170. They appear to be for a later 172. (C172’s after SN 55001 used different riser PNs although the same illustration was used in the IPC.... maybe to save artistry costs.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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oldtrucksrule
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Re: Exhaust Risers too long??

Post by oldtrucksrule »

After reconsideration, I sent the risers back to the seller and went with AWI.

Thanks for the input
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Joe Moilanen
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Re: Exhaust Risers too long??

Post by Joe Moilanen »

AWI is great, but I still had to tweek the bent riser on the pilots side to get it to fit right. Measuring how much more the bent riser (front one/#6 Cylinder) had to be bent, I bolted the riser flange to a piece of scrap flat bar, put a piece pipe that fit snuggly in the riser, heated it up at the bend and bent it to where it needed to be. I checked the amount that it moved by using a square from the scrap flat bar to the flange on the riser, marking on the flat bar before and after to check difference. It then fit perfectly, also used "muffler" tape on the clamp connection. No leaks.

Joe
4518C
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GAHorn
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Re: Exhaust Risers too long??

Post by GAHorn »

The problem is where to place blame.... is it really the riser..? Or is it the muffler...? Or is it a cylinder exhaust flange out of spec....?

Just because what was removed seemed to fit... doesn’t mean the previous fitment wasn’t also needful of “malletizing”. Cylinders are fitted to crankcase/sumps with bolt and studs and there is a certain amount of “slop” that can exist in this entire sequence of castings, bolts/studs, cylinders, flanges, risers, mufflers.... Just sayin’. These things are rarely “drop in” replacements.

In any case, new risers being fitted to used mufflers often need careful fitting. I’ve had good success by loosely bolting them together and then snugging them up after they’re in-place.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Joe Moilanen
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Re: Exhaust Risers too long??

Post by Joe Moilanen »

GAHorn wrote:The problem is where to place blame.... is it really the riser..? Or is it the muffler...? Or is it a cylinder exhaust flange out of spec....?

Just because what was removed seemed to fit... doesn’t mean the previous fitment wasn’t also needful of “malletizing”. Cylinders are fitted to crankcase/sumps with bolt and studs and there is a certain amount of “slop” that can exist in this entire sequence of castings, bolts/studs, cylinders, flanges, risers, mufflers.... Just sayin’. These things are rarely “drop in” replacements.

In any case, new risers being fitted to used mufflers often need careful fitting. I’ve had good success by loosely bolting them together and then snugging them up after they’re in-place.
Exactly, a little bit of movement at the cylinder base equates to quite a bit at the muffler end of the riser.

Joe
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