C-145-2H Engine Overhaul

How to keep the Cessna 170 flying and airworthy.

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nippaero
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Re: C-145-2H Engine Overhaul

Post by nippaero »

I looked at them and thought about it. I didn't want to spend the extra $. I figure the new rubber hoses, clamps and tubes should last me many hours before I have to worry about them leaking. Time will tell though.
1952 170B
N8180A s/n 25032
counsellj
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Re: C-145-2H Engine Overhaul

Post by counsellj »

"But they are not cheap to overhaul and a couple of drops of oil down the road is well, down the road. 70 year old technology, which BTW matches the rest of the engine, mags, carb, and starter in my case, is whats going back into the 70 year old plane."

Of course most of our 70 year old C-170 pilots leak a little as well. :lol:
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170C
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Re: C-145-2H Engine Overhaul

Post by 170C »

I have no personal experience doing so, but have heard of others using an adhesive (glue ?) on the push rod tubes as they fitted the rubber gaskets/clamps on the cylinders and that seemed to prevent oil leaks. I have never understood why they leak, and some of them will eventually, since there is no pressure on the oil draining back into the sump. Maybe there is a better clamp than those we have? Hot oil sure can find the smallest possible place to leak :cry: Keeps the belly & tail wheel springs from rusting :mrgreen:
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nippaero
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Re: C-145-2H Engine Overhaul

Post by nippaero »

It's probably from the rubber getting hard over time. The old hoses were rock hard and several had to be cut off with a razor knife. My new rubber hoses are flexible and the new clamps are rather tight. I would be really surprised if I had a leak anytime soon. I ended up with another full set of hoses and clamps that I will keep for spares. We use some plyobond on the nose seal to keep them from leaking. I guess one could use a little on the hoses as well but I am not going to worry about it.

Here the cylinders are on :D

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1952 170B
N8180A s/n 25032
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nippaero
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Re: C-145-2H Engine Overhaul

Post by nippaero »

It could be an effort in futility I know. :D

I wish the snow would melt around here. Now I'm getting anxious to see this thing run soon. I keep thinking summer....
1952 170B
N8180A s/n 25032
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nippaero
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Re: C-145-2H Engine Overhaul

Post by nippaero »

I am debating on the carb. Where did you get yours overhauled/exchanged?
1952 170B
N8180A s/n 25032
n3833v
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Re: C-145-2H Engine Overhaul

Post by n3833v »

I just replaced my carb with a serial plate and no identifiable numbers. Aero in Stock had a special and I got an exchange and they would accept my carb for a core.

http://aeroinstock.com/?_ga=1.267154318 ... 1486479705

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170C
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Re: C-145-2H Engine Overhaul

Post by 170C »

So nice and clean!
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Re: C-145-2H Engine Overhaul

Post by GAHorn »

Aryana wrote:... :lol: I really enjoyed building my O-300 years ago and am itching to do another.
IMG_2826.JPG
*1 aviation unit = $1000 USD
It's not time yet but... if it makes you feel better.... you can do mine. 8)
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Re: C-145-2H Engine Overhaul

Post by GAHorn »

nippaero wrote:Someone had asked about the old gears and how bad they were worn. I have heard that a big source of metal in the oil on these engines if from the starter gears....]
Sounds like imagination at work, IMO. The starter gears are engaged only a miniscule amount of time compared to all the other rotating gears.

If properly adjusted (in accordance with the engine overhaul manual) the gears do not clash when the starter is engaged. I'm keeping my original Delco Remy starter because it's Robust, Dependable, Inexpensive to repair or rebuild, and they can be found anywhere/anytime.

The weak link is that roller-clutch, ...but the mfr'r has introduced a nice program for those that visit their website.
'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: C-145-2H Engine Overhaul

Post by cessna170bdriver »

And.... the cut of the gears, kind of a scallop on the leading edges to enable smooth engagement, appears to be wear to those used to seeing straight cut spur gears. That said, my first overhaul was due to a misadjusted starter cable that left the gears engaged about 1/16-1/8'inch.
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9976AJds
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Re: C-145-2H Engine Overhaul

Post by 9976AJds »

I have really enjoyed your overhaul photos and ideas. My engine is almost finished, an 0300-C, last overhauled in 1984. I have used many of the same vendors as you. I drove my crank, rods, lifters, and cam to Aircraft Specialty in Tulsa. Bobby gave me the tour, and I am completely happy with my rebuilt parts.

Regarding the Carb. MA3SPA, mine had two overdue AD's, Two Piece Venturi, and Old Float System. So I did exchange with Marvel Schebler. I have no idea if it will work any better than my old unit, but with complete overhaul hope to enjoy another 10 years of smooth flying.

Regarding the magnetos, Kelly Aero, overhauled mine, they also had an overdue AD on the rivets holding the drive plate.

I was able to save my baffling, but have over 40 hours in repairs, and polishing. I can use as mirror for shaving, or signaling rescue, if an off airport landing in the bush. Thanks for the great resource, see you at Sun and Fun. JD Smith
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nippaero
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Re: C-145-2H Engine Overhaul

Post by nippaero »

It's been a while since I had a chance to sit down and update this thread.

Rockers and covers: The rocker covers on the Millenium O-300 cylinders do not come powder coated black like the larger cylinders. I was going to have them coated but decided I like the gold color look. They match the pushrod tubes which looks nice.

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1952 170B
N8180A s/n 25032
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nippaero
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Re: C-145-2H Engine Overhaul

Post by nippaero »

Putting together the induction system. If you look closely you can see the new powder coated baffling from Airforms.

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1952 170B
N8180A s/n 25032
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nippaero
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Re: C-145-2H Engine Overhaul

Post by nippaero »

Things are winding down and this motor is almost done. It is going to get set aside while work continues on the plane. I won't hang the engine until after the plane is painted.

I installed a new generator, new plugs and two new long exhaust risers from AWI.

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1952 170B
N8180A s/n 25032
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