1961 Cessna 175 project

docmirror said:
I think what I would do is offer $3500, do the deal, then take the jugs off and have them cleaned up. inspect and clean the cam lobes best I can, pre-lube with some lithium grease, put it all together with new oil and hope for the best.

No way would I try to crank the engine after sitting so long. It's gonna make some metal on start up, and then grind it through everything that gets pressure lubed. I might even wash down the innards with some stodard solvent, blow it out, then coat the cam, install the jugs and give it a try.

YMMV, do anything you want once you own it.
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My 0-300-D sat from 1992 until fall of 2012. #5 cylinder was off and the previous owner panicked and sold me the aircraft. I planed to over haul it anyway so I trucked the aircraft home and tore the engine down. There was absolutely nothing wrong with the engine I should have replaced the cylinder and flown it home.

These old Continentals will set for years and start right up and run fine. The first 30 minutes will tell you what you need to know.
 
docmirror said:
Do rings tend to stick on these jugs? I'm really worried about a stuck then broke ring.

I did a Jag 3.8L engine about 12 years ago. The owner found it in the proverbial barn, and couldn't wait to make it run. we lubed it and once we got it running, it broke three rings in a row from 1-3. Wound up taking the engine all apart and had to rebore it.
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After you run it 30 minutes you will know by looking in the cylinder. They normally don't break rings, If it does on start up, you will know right away, that cylinder will go to melt down quickly. if it does not, it will run for ever.

It will smoke like a smudge pot for a few minutes. let it run until it cleans its self up.
 
Thanks. The nice thing is, if it does break one, the jug can come of on its own, and not have to redo the whole thing. Clearly the Conti is a lot looser than a Jag inline 6.

Also I think it makes a diff where it sits. I'm surprised it would sit for so long in a humid climate and still run smooth. Thinking if it were in AZ, no problem, but in Houston might be much worse.
 
synclavier said:
IIRC, there are TIME limited parts that Cessna has established through revisions in the 172/175 manuals including vacuum hoses, vacuum filters, seat belts, trim tab actuators, so on... In that case, would you wait 10 years from the date of the new logbook to replace them, or would you replace the parts immediately to ensure compliance?
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Like Tom said if its not an AD or a TCDS listed time replacement ... its not required
Skylane81E said:
Expect the worst, hope for the best!
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Yup

synclavier said:
I checked the backlash on the gear this afternoon. There was about 1/4'' of play. I'm going to try to borrow a battery and get her started sometime in the next week. Before I do that, should I drain the oil and remove the old filter and cut it open to see what (if any) metal is in there, or should I have it sent off for analysis?
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No offense, but a lot of the questions you are asking is stuff that you should know as an A&P. Has it been a long time or something?

Its a big project. Nothing wrong with that, but just know that. Im with Tom. I think you should run it. Nothing wrong with that. I know I have run engines that have sat that long.
 
synclavier said:
I checked the backlash on the gear this afternoon. There was about 1/4'' of play. I'm going to try to borrow a battery and get her started sometime in the next week. Before I do that, should I drain the oil and remove the old filter and cut it open to see what (if any) metal is in there, or should I have it sent off for analysis?
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Why borrow a battery? You aren't going to fly it, so a set of jumper cables and a working automobile ought to get it started. OR at worst cables and a spare auto battery on the ground.

Jim
 
weirdjim said:
I started looking for the rd gear backlash limits in the maintenance manual and came up dry. If you know where they are, could you save me a few hours of research?

Thanks,

Jim
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In the table of Limits, gear backlash. The new parts are minimum .000", max .004", serviceable limits .008". I imagine the OP is measuring the slop at the prop tip, so one would need the propshaft gear meshing diameter to calculate the play at the tip. Still, 1/4" is 31 times the serviceable limit, and I don't think the prop radius will be 31 times the gear radius. Of course, there's also the slop between the quill shaft splines and quill shaft gear added into that tip slop.

Dan
 
flyingmoose said:
No offense, but a lot of the questions you are asking is stuff that you should know as an A&P. Has it been a long time or something?
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Could be big iron sheetmetal guy ? Could be big iron backshop guy that only services APUs ? Could be a lot of legimate reason why not up to snuff on GA/91 procedures.
 
The larger question is...who in their right mind wants a swept tail 175?

That just ain't right!
 
weirdjim said:
I started looking for the rd gear backlash limits in the maintenance manual and came up dry. If you know where they are, could you save me a few hours of research?

Thanks,

Jim
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1/4" free play at the prop tip is pretty much average, this will include the gear box gears, the spindle clearances, and the crank free play before it starts to move the pistons and accessory gears.
 
Yesterday, I was eyeballing the backlash from the prop tip. It looked like 1/4''. Today, I took a yardstick out there and measured for real. The backlash is only 1/8". I rocked it back and forth several times and measured several times. It's 1/8'' in.

Thanks Tom and Doc for your detailed info!

I very much appreciate the input coming from this thread. Most of it is helpful. Thank you!

Question: The plane's registration ran out 2 years ago and was not renewed. Will the FAA want to do an inspection before a new N number is assigned?
 
This thread is very interesting to read for even us non-involved. Please keep us up to date, I'm curious to see how it looks if/when you purchase the plane.
 
synclavier said:
Yesterday, I was eyeballing the backlash from the prop tip. It looked like 1/4''. Today, I took a yardstick out there and measured for real. The backlash is only 1/8". I rocked it back and forth several times and measured several times. It's 1/8'' in.

Thanks Tom and Doc for your detailed info!

I very much appreciate the input coming from this thread. Most of it is helpful. Thank you!

Question: The plane's registration ran out 2 years ago and was not renewed. Will the FAA want to do an inspection before a new N number is assigned?
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no, go on line and re-register it in the (now) owner's name. that way there will be a title / registration on file.

Read about it here

http://www.faa.gov/licenses_certificates/aircraft_certification/aircraft_registry/reregistration/
 
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Sounds better. You gonna clean it out and run it?

BTW, I'm just along for the ride, I shopped them, but really am no kind of guy on the plane. I just like an overpowered plane, and the 175 fits that. I was looking at mods to make it faster, and there's a few folks out there offering gap seals, and better pants. Wondered if it would help much.
 
Definitely going to run it. I have few things to do to it before that happens. All the wheels are rotten, so they have to be changed, at which point I can take her to the wash rack and give the engine a scouring. So, I probably won't get to run her until the end of next week due to that and my work schedule. I don't want to be premature in starting the engine up after that long, so I'm going to take Tom's prescriptions and be thorough about doing so. I'm in no rush.

Again, thanks to all who have participated in the discussion and have shared their opinions and advice. I will keep you informed on any new developments.
 
synclavier said:
I'm going to take Tom's prescriptions and be thorough about doing so. I'm in no rush.
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Buy a gallon of WD40 tomorrow and fill the cylinders and let it set.
 
Tom-D said:
Buy a gallon of WD40 tomorrow and fill the cylinders and let it set.
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curiosity: why recommend a silicon fluid rather than a hydrocarbon fluid? Is the recommendation based on experience or is there something else behind the choice?
 
Clark1961 said:
curiosity: why recommend a silicon fluid rather than a hydrocarbon fluid? Is the recommendation based on experience or is there something else behind the choice?
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any light oil will work. WD 40 is easy to find. I have some left over mil spec 1010 preservation oil I use. You simply need to get some lube into the ring groves because the old oil has long since gone away.

Another thing it will do is carry away the rust debris broken loose by the rings from his turning the engine by hand.

It's best if you can get each piston on compression stroke about 1 inch before top dead center, fill the cylinder with light oil and replace the top plug and gently add a little pressure to the piston by turning the prop by hand, you can feel the oil leaking past the rings, then remove all the plugs. Do this to each cylinder. then remove all pugs then crank the engine on the starter until you get oil pressure prior to the start. IOWs pre-oil it on the starter.
 
kgruber said:
It kills me, the WD-40 haters of the internet!

WD-40 has no "silicon." It has no silicone either.

http://wd40.com/files/pdf/msds-wd494716385.pdf
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I'm sorry but the MSDS does not say a single thing about it not having any silicone in it. Maybe you are just a tad reactionary on the topic?

WD-40 really is a poor fluid choice for helping deal with rust. If you want to deal with rust then use something that will attack the rust. There are numerous products which do that and are reasonably effective.

As a lubricant, WD-40 is pretty crappy. I do not use it and do not recommend it's use as a lubricant. Do you really want to be using mineral spirits as a lube?

As a water displacing agent, well that's what WD-40 was designed to do. The folks at WD-40 say so themselves.
 
Clark1961 said:
I'm sorry but the MSDS does not say a single thing about it not having any silicone in it. Maybe you are just a tad reactionary on the topic?

WD-40 really is a poor fluid choice for helping deal with rust. If you want to deal with rust then use something that will attack the rust. There are numerous products which do that and are reasonably effective.

As a lubricant, WD-40 is pretty crappy. I do not use it and do not recommend it's use as a lubricant. Do you really want to be using mineral spirits as a lube?

As a water displacing agent, well that's what WD-40 was designed to do. The folks at WD-40 say so themselves.
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That is hilarious. A WD-40 hater that can't spell or even read!
 
Clark1961 said:
As a lubricant, WD-40 is pretty crappy. I do not use it and do not recommend it's use as a lubricant. Do you really want to be using mineral spirits as a lube?
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I assume that the reason to use any oil at all is as a penetrating fluid and in that case you want a very low viscosity oil.

WD-40 is fine but PB Blaster, AeroKroil, and especially Liquid Wrench are all better in my (limited) opinion.
 
50% ATF + 50% acetone is lab proven to be a better rust-busting penetrating "oil" than liquid wrench, WD-40, Kroil, PB Blaster, or anything else.

Well, except for Mouse Milk. They didn't include mouse milk in this head-to-head lab competion. Mouse Milk rocks.

Machinist's Workshop magazine actually tested penetrants for break out torque on rusted nuts. Significant results! They arranged a subjective test of all the popular penetrants with the control being the torque required to remove the nut from a "scientifically rusted" environment.


Penetrating oil .......... Average load
None ..................... ...516 pounds
WD-40 .................... ..238 pounds
PB Blaster ............... ...214 pounds
Liquid Wrench ..............127 pounds
Kano Kroil ............... ...106 pounds
ATF-Acetone mix...........53 pounds

The Automatic Transmission fluid (ATF)-Acetone mix was a "home brew" mix
of 50 - 50 automatic transmission fluid and acetone.

Note the "home brew" was better than any commercial product in this one particular test. A local machinist group mixed up a batch and all now use it with equally good results. Note also that "Liquid Wrench" is about as good as "Kroil" for about 20% of the price.
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timwinters said:
50% ATF + 50% acetone is lab proven to be a better rust-busting penetrating "oil" than liquid wrench, WD-40, Kroil, PB Blaster, or anything else.

Well, except for Mouse Milk. They didn't include mouse milk in this head-to-head lab competion. Mouse Milk rocks.
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Heh, you read the same things I do. :)

I wasn't sure if Acetone+ATF should be something to go in a cylinder so I left it out.
 
Acetone will boil off/vaporize in a few minutes with the crankcase vent open. ATF will only help clean lube the cam extra and maybe clean out the lifters if they are hyd.

But - like Tom said, what ever you have light oil laying around will do the job. Mainly just flex the rings in the lands a little because they are so brittle to keep them from breaking.

We will not discuss pulling it through by hand will we. DOH! :yikes:
 
Mention WD 40 and every body goes ballistic, all you need in the cylinders is any light oil to carry away the red iron oxide that the rings will brake loose, WD 40 will do the job just fine and not be harmful when left in the crank case to mix with the first oil placed in there too.
 
docmirror said:
We will not discuss pulling it through by hand will we. DOH! :yikes:
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He has already been moving the prop/crankshaft, if the rings aren't broke already, they will not brake when cranked by the starter.

I don't mind moving the prop by hand to achieve what the OP needs to do.
 
Yeah, I know we've been moving it. No worries. If the rings are stuck to the lands and not stuck to the cylinder they can still crack, but much less chance if they have some light lube pushed around in there.

BTW, the WD-40 others are concerned about contains a surfactant which is a fancy word for a detergent kind of cleaner that will carry the loose goo down to the filter, if it has one. If it doesn't have one, now would be a fabulous time to buy and install one. A small investment that could be an engine saver right about now.
 
docmirror said:
Yeah, I know we've been moving it. No worries. If the rings are stuck to the lands and not stuck to the cylinder they can still crack, but much less chance if they have some light lube pushed around in there.

BTW, the WD-40 others are concerned about contains a surfactant which is a fancy word for a detergent kind of cleaner that will carry the loose goo down to the filter, if it has one. If it doesn't have one, now would be a fabulous time to buy and install one. A small investment that could be an engine saver right about now.
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The rings will not stick to the cylinder, rings are chrome, they will cause electrolysis on the cylinder wall and leave a ring of pits where they sat all these years. but to stick,,,, no.
 
So...

Thought I'd give an update on what's happened since my last posts. A couple weeks ago, I kroiled the spark plugs and let them sit overnight. Next day, broke the top plugs loose (wow, were they tight). I filled the cylinders with WD-40 before I left for my work trip out east, a week long. When I came back, I took all the plugs out, slowly hand propped the engine through, and puked out some of the WD.

I cursorily looked inside the cylinders and I didn't see or hear anything to suggest stuck rings or obvious problems. I cranked over the engine (w/o plugs) and more of the WD came out the exhaust, as expected. The oil in this engine must have been changed right before the last time she was flown, because it's blonde in color and doesn't show of any deposits or sludge.

The battery that was currently installed (Gill G-25) wasn't making the numbers, so I replaced it with a new one. I lubed and actuated the engine controls as best I could, but they are still a bit hard to move, with the exception of the throttle. I took a look inside the fuel tanks and they were bone dry, so I ordered the truck over and did 5 per side. I sumped the tanks, and other than some flecks of dirt in the intital mL, all seems fine.

I strapped in, went through the startup checklist, and with some trepidation, reached for the keys... KAWARR, KAWARR,KAWWARR... COUGH COUGH... more WD puked out the exhaust. On or about the 7th crank she sputtered a bit. On the 8th crank, she came to life, and it was the most beautiful sound I'd hear in a long time.

Other than smoke from burning WD, no smoke from the exhaust. Ran her to 1200 and then to 1800. A mag check revealed the L was good, but when set to R on the ignition, the engine ran rough. All gauges seem to work except the oil pressure gauge, which sucks because that's the one I was looking to for answers right off the bat. When mixture leaned to cutoff, there was the slight rise in RPM, as expected. I'll put up a youtube link of her running soon.
 
now put 30 minutes run time on it and change the oil again.

never allow it to idle 1100-1200 RPM is enough to load that prop and keep the gear box happy.
 
Dean said:
Do someone a favor and offer about $3000 and scrap it.
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There is always a Debbie Downer out there lurking around, incapable of contributing anything positive to a discussion, except to be the first to shoot down someone's dreams and goals.

Thank you, sir for filling that role, for being that person. How does it feel to know that you're that person, to know that you're that little social statistic? :yesnod:

No, I think I shall move forward with this airplane. It has been a fulfilling experience thus far to get it running and rolling. Restorative maintenance on one's own airplane is a catharsis relatively few get to experience, and even less as the pilot of it. I'm having a great time and, all things considered, spending a relatively small amount of money doing so.

So, welcome to the discussion, Mr. Downer. We're so glad you're here... :goofy:
 
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