Installing A TCM IO360

[blueldr]

David,
I must be mistaken on the length of the prop I used. It came off of a C-182 when a ffiend of mine installed a three bladed prop. Maybe the "C-182" stuck the number in my mind.
I noticed that "Metal Master" has his intake "Manifold/Runner" installed normally. I had to reverse the direction of the whole manifold on mine and trimmed the front of the resulting right runner off at an angle to get cowling clearance on the right front of the top cowl. It will fit right back on the engine when reversed 180 degrees.
My airplane was a 52 B model and maybe there is a little difference with the A model cowling.

[johneeb]

I also considered not reversing the air intake manifolds and decided to reverse them. I cannot recall why, maybe the air-cleaner. I did not have to modify the angle of the end of the intake manifold.

[blueldr]

John,
Your picture above shows the prop flange pretty well off center in the cowling. Was that a final position or did you correct that in some manner?
On my installation, after reversing the intake manifold, the end of the right hand intake runner was almost touching a reinforceing strip in the upper cowling adjacent to the long piano hinge. This reinforceing channel may have been a non-standard part added before I acquired the airplane. It was so close that I thought that if it was to come into contact with the intake runner that it might wear a hole in the intake which could affect the mixture of the right front cylinder. I pruned the front of the runner off at an angle to provide better clearance. Getting everything in under the top cowling was quite a job. I wish now that I had taken more pictures.

[Metal Master]

[quote="johneeb"]I also considered not reversing the air intake manifolds and decided to reverse them. I cannot recall why, maybe the air-cleaner. I did not have to modify the angle of the end of the intake manifold.
I was talking with Tom Anderson via e-mail yesterday concerning his experiences with others installations as concerns cowl alignment to the center line of the crankshaft. I have noted that on both my O-300 and IO-360 installation that the crank shaft is offset to the left as viewed from the pilot’s seat. Just the opposite of what is apparent in your picture. Tom’s comment was essentially it was all over the place and varied from installation to installation. I did an internet search and found two pictures of early cowl installations demonstrating exactly the same offset as on my airplane. See attached. I am a lot less concerned about it now.
Jim

[Metal Master]

Noting that the 170A cowl and later 170B cowls are entirely different. Of note is that in Johnebs picture of the forward right induction elbow installed in the normal orientation. It nearly blocks the upper cowl inlet and comes almost flush with it. Mine does not even come within 4 inches of the front of the cowl and nowhere near the cowl inlet. The left side also has at least 2 inches of clearance to the front of the cowl and is only riding on the upper cowl lip which can easily be cleared. Considering that the 170 A has the internal box cowl and the later 170Bs had a pressure cowl I am sure it is what contributed to the differences. I will take what I can get. It seems to be fitting with little alteration. I still have to address propeller spinner fit issues. This installation does eliminate the internal box cowl and I have a plan to better secure the cowl doors. I will attach pictures of this once it is accomplished.
Jim

[johneeb]

John,
Your picture above shows the prop flange pretty well off center in the cowling. Was that a final position or did you correct that in some manner?
On my installation, after reversing the intake manifold, the end of the right hand intake runner was almost touching a reinforceing strip in the upper cowling adjacent to the long piano hinge. This reinforceing channel may have been a non-standard part added before I acquired the airplane. It was so close that I thought that if it was to come into contact with the intake runner that it might wear a hole in the intake which could affect the mixture of the right front cylinder. I pruned the front of the runner off at an angle to provide better clearance. Getting everything in under the top cowling was quite a job. I wish now that I had taken more pictures.

Dick,
I did not try to correct the location, I went with the assumption that the new motor mount was correct and the cowling during its lifetime had lived through some hard knocks. Also having flown the airplane for awhile now if I could I would cant the prop flange at even more of a down angle to try and eliminate some of the nose down elevator trim required in high speed cruise (I think the 180-5s get some of their speed because they have a trim-able horizontal stab).

Jim,
In your pictures the back of your prop flange does not appear to have any clearance with the cowling, is that a optical allusion? I to struggled with making the spinner work out I had to reverse the backing plate and trim the excess (I think Mr. Dremel did the trimming).

[Metal Master]

Dick,
I did not try to correct the location, I went with the assumption that the new motor mount was correct and the cowling during its lifetime had lived through some hard knocks. Also having flown the airplane for awhile now if I could I would cant the prop flange at even more of a down angle to try and eliminate some of the nose down elevator trim required in high speed cruise (I think the 180-5s get some of their speed because they have a trim-able horizontal stab).

I agree with this it is the same situation we discovered years back with the 1956 172 Tail dragger conversion after we installed the Lycoming O-360 A1A.

Jim,
In your pictures the back of your prop flange does not appear to have any clearance with the cowling, is that a optical allusion? I to struggled with making the spinner work out I had to reverse the backing plate and trim the excess (I think Mr. Dremel did the trimming).

John
It is not an optical illusion there is not any clearance at this point. It literaly sits directly behind the crankshaft flange. The nuts for the propeller install on the back of the crankshaft flange and the hole in the cowling is only 3 and 1/4 inch in diameter. The cutout hole in the cowl will have to be enlarged to at least 4 and 1/2 inches just to clear the crankshaft flange and propeller nuts if not larger to allow foe movement of the engine. I will not have to make any changes to the flange of the cowl such as you did on your installation as there is no flange on the 170A cowl. I am not going to make any of these changes until the engine is actually bolted to the airframe. It seems my propeller should install with no issue but I will have to wait and see.

170 progress 2004-03-27 001.jpg

[/quote]

[GAHorn]

Re: previous question about not using a spinner with a constant speed : Spinners do more than appearance... They smooth-out airflow entering the cowling and can affect engine cooling because they affect the high-pressure area in the cowling.
Unless one goes to the trouble of multiple-probes to investigate for stagnant/turbulent areas to discover hot-spots.... one cannot know much about it. OEMs spend a lot of time/money looking for hot-spots, turbulent entry air, and wind-induced vibration (think cowling cracks) when developing spinner requirements.
But in a "nutshell" (pun intended), if you don't mind the looks.... don't suffer hot cylinders/oil temps... don't experience new vibrations and cowl-cracking.... AND...if the installation-certification does not require a spinner.... then there should be no undue concern about not having one.

[bagarre]

Re: previous question about not using a spinner with a constant speed : Spinners do more than appearance... They smooth-out airflow entering the cowling and can affect engine cooling because they affect the high-pressure area in the cowling.
Unless one goes to the trouble of multiple-probes to investigate for stagnant/turbulent areas to discover hot-spots.... one cannot know much about it. OEMs spend a lot of time/money looking for hot-spots, turbulent entry air, and wind-induced vibration (think cowling cracks) when developing spinner requirements.
But in a "nutshell" (pun intended), if you don't mind the looks.... don't suffer hot cylinders/oil temps... don't experience new vibrations and cowl-cracking.... AND...if the installation-certification does not require a spinner.... then there should be no undue concern about not having one.

It's the required part that I'm not sure of.

[hilltop170]

Noting that the 170A cowl and later 170B cowls are entirely different. Of note is that in Johnebs picture of the forward right induction elbow installed in the normal orientation. It nearly blocks the upper cowl inlet and comes almost flush with it. Mine does not even come within 4 inches of the front of the cowl and nowhere near the cowl inlet. The left side also has at least 2 inches of clearance to the front of the cowl and is only riding on the upper cowl lip which can easily be cleared. Considering that the 170 A has the internal box cowl and the later 170Bs had a pressure cowl I am sure it is what contributed to the differences. I will take what I can get. It seems to be fitting with little alteration. I still have to address propeller spinner fit issues. This installation does eliminate the internal box cowl and I have a plan to better secure the cowl doors. I will attach pictures of this once it is accomplished.
Jim

Jim-
You may have already considered this but the top of the air-box cowl flexes downward in flight. I don't know whether the pressure cowl does it or not. Most air box cowls have had the cowl hinge support angles trimmed where they contact the front edge of the air box. I noticed in your pictures that your cowl hinge support angles has had some trimming done there. Just a thought but I don't know where the cowl will flex to with the air box gone if you use one of those.

[Metal Master]

Jim-
You may have already considered this but the top of the air-box cowl flexes downward in flight. I don't know whether the pressure cowl does it or not. Most air box cowls have had the cowl hinge support angles trimmed where they contact the front edge of the air box. I noticed in your pictures that your cowl hinge support angles has had some trimming done there. Just a thought but I don't know where the cowl will flex to with the air box gone if you use one of those.[/quote]

The center section of the upper cowl is going to be completely replaced with .032 aluminum sheet and new angle aluminum. I have already replaced the doors with .032 aluminum. but they are going to be replaced again. At this point the only reason the cowl is fit on the jig is to allow fitting of the baffling. The drawings of Toms baffling for the 170 series are seriously lacking in this respect from a dimensional aspect, they would not have fit inside the cowl.
Jim

[Metal Master]

Re: previous question about not using a spinner with a constant speed : Spinners do more than appearance... They smooth-out airflow entering the cowling and can affect engine cooling because they affect the high-pressure area in the cowling.
Unless one goes to the trouble of multiple-probes to investigate for stagnant/turbulent areas to discover hot-spots.... one cannot know much about it. OEMs spend a lot of time/money looking for hot-spots, turbulent entry air, and wind-induced vibration (think cowling cracks) when developing spinner requirements.
But in a "nutshell" (pun intended), if you don't mind the looks.... don't suffer hot cylinders/oil temps... don't experience new vibrations and cowl-cracking.... AND...if the installation-certification does not require a spinner.... then there should be no undue concern about not having one.

It's the required part that I'm not sure of.

The STC calls for a spinner with a fixed pitch or the constant speed propeller

[bagarre]

The center section of the upper cowl is going to be completely replaced with .032 aluminum sheet and new angle aluminum. I have already replaced the doors with .032 aluminum. but they are going to be replaced again. At this point the only reason the cowl is fit on the jig is to allow fitting of the baffling. The drawings of Toms baffling for the 170 series are seriously lacking in this respect from a dimensional aspect, they would not have fit inside the cowl.
Jim

I'd be very interested in talking to you about any cowl mods you feel are needed as well as baffle dimensions.
I havent started on the baffles yet for that very concern. Not only do the drawings appear to lack some key measurements but I don't think they are right for the 170A cowl. I see a lot of custom tin work needed in there.

[Metal Master]

The center section of the upper cowl is going to be completely replaced with .032 aluminum sheet and new angle aluminum. I have already replaced the doors with .032 aluminum. but they are going to be replaced again. At this point the only reason the cowl is fit on the jig is to allow fitting of the baffling. The drawings of Toms baffling for the 170 series are seriously lacking in this respect from a dimensional aspect, they would not have fit inside the cowl.
Jim

I'd be very interested in talking to you about any cowl mods you feel are needed as well as baffle dimensions.
I have not started on the baffles yet for that very concern. Not only do the drawings appear to lack some key measurements but I don't think they are right for the 170A cowl. I see a lot of custom tin work needed in there.

Bagarre
I have been working on making the baffling starting with the rear and working forward. The dimensions on the drawings would put the edge of the baffling completely outside the cowl. I have cut at least an inch off the outer edges. I have been making notes on the drawings as I go. I will be taking some pictures of this over the next week but I have several airplane project irons in the fire. Send me a private message and I will give you my personal e-mail and phone #
Jim

[blueldr]

When I installed my IO-360 conversion, I never did find a spinner that had the bullet shape that I wanted. It was a matter of horizontal clearance of the backing plate from the front of the cowling. I finally ended up with a pointed spinner with a forward slopeing backing plate. It worked fine, but looked like hell on the C-170.
There is an aviation "junk yard" in Artesia, New Mexico, that specializes in spinners. They have been very helpful to others that I know of.