N3458D Finally home!

[Paul-WI]

Hi;

New member here so please be kind

Just picked up 58D (1955 170B) last Friday and everything went well except a couple of minor glitches. Plane only was flown 9 hours the past 10 years so am curious how the engine will hold up. Has about 400 SMOH (1600 TT on plane). The previous owner paid for the annual and repair of the 2 middle cylinders as the valves where stuck. We put about 3 hours on it this weekend and seems to run great. Time will tell!

Anyway, I was wondering if there is an easy way to identify whether this has the solid axles or not without pulling the wheels off. Another pilot at our airport has a set he wants to sell me and if I don't have them, I will purchase the set from him as he didn't need them.

Also, any advice on skis? It came with a set of Schneider 4000 penetration skis I want to install this winter.

Thanks and hope to meet some of you in the future!


Paul

[zero.one.victor]

I think I'd recommend some mystery oil and frequent oil changes (maybe 10 hour intervals) for the first 30 or 40 or 50 hours. 9 hours in 10 years is probably just enough to get a lot of rust & corrosion happening. Best to get it churned up into the oil and outa there.
Hope it works out well for you. A friend bought and semi-restored a Grumman Yankee a while ago that had sat for several years. Compressions came right up, oil looked real good after the first couple changes, and it seems to be running just fine.

Eric

[C170BDan]

Sounds good, Paul! Hope your engines runs well for you. What would your serial number be? 3458D sounds close in N# to mine but wondered how close in serial number.

Mine is a 56 model built in late 55 and is 27010.

[cessna170bdriver]

Paul,

Congratulations on your new toy!

With an airplane that's sat as much as yours seems to have, if you have any problems, it will likely be corrosion in the engine. I would have suspected problems with rust in the cylinder bores. How did they look? Any rust? Did they take the cylinders off, or did they work the valves through the sparkplug holes? Also, if you have any more problems with stuck valves, remove the cylinder and take a look at the cam. If you don't have any problems with rust on the cylinders or on the cam, you're probably ok. With that low of a time since overhaul, I'd recommend starting an oil analysis program. It will take several oil changes to get a good baseline, but if things start going south in the future, you'll know quickly.

As far a the axles go, if you don't have wheelpants, just remove the hubcap and take a look at the end of the axle. If you have wheel pants, you'll have to remove them, jack the leg off of the ground and remove the axle nut to look at the end of the axle. You can readily tell if they are solid or not. If the airplane has been on skis, I would suspect that they are solid, or possibly steel, but it would be prudent to check for sure.

Happy Flying!
Miles

[GAHorn]

Eric and I differ in our regard for MMO. We do agree that an early oil change or two is a good idea, primarily to check the screen/filter for metal.
I would not be anxious to dislodge anything else, nor would I recommend "de-sludging" or other aggressive cleaning of an engine internally. (You got one running good? And you want to do what...?)
Varnish and other coatings in an engine actually serve a useful purpose. They protect against rust and corrosion by providing a barrier to oxygen and moisture in the atmoshphere. Removing that stuff and "churning" it up, circulating it throughout the engine is the worst thing I can imagine. (But I've got a pretty dull imagination. I tend to stick with approved fluids and operating procedures.)

[JJH55]

Welcome Paul,
You can easily check for the solid axles by sticking a long narrow screwdriver or equivilent through the center of the nut that secures the wheel to the axle. If you have solid axles the screwdriver should only go in an inch or two. If its hollow it will go all the way through to the gear leg.
JJH55

[GAHorn]

Welcome Paul,
You can easily check for the solid axles by sticking a long narrow screwdriver or equivilent through the center of the nut that secures the wheel to the axle. If you have solid axles the screwdriver should only go in an inch or two. If its hollow it will go all the way through to the gear leg.
JJH55

Well... maybe. If he has wheel fairings or the type axle nuts for fairings, he'll be unable to do that. He'll have to remove the nut and look.
But if the axle nuts are the common, castellated type, you can just look in the end of the axle with a flashlight. Solid axles are...well...solid almost to the end of the axle.

[Bruce Fenstermacher]

Yes sir Paul I'd be changing the oil like right now. You've probably scrapped all the rust thats going to get scrapped off and you don't want that running through our engine.

[jrenwick]

Just an additional point related to something very important that Miles said: if your axles are hollow, they could be either aluminum or steel. Hollow aluminum axles are more prone to failure than solid aluminum axles; but hollow steel axles are stronger than solid aluminum ones, and are often used with skis (depending on the ski STC, they may even be required).

There's a very long and somewhat confusing thread here: http://cessna170.org/phpBB2/viewtopic.php?t=1361 that gives all the part numbers for the three different types, and sources for the steel ones. As noted in a subsequent thread, the steel axles are now approved for 170s.

Rhinelander isn't all that far from Minneapolis; I hope we'll meet some time! Once in a while I get over to Boulder Junction to visit my brother's cabin....

Best Regards,

John

[CraigH]

Like some of the others have said, I'd highly recommend regular oil analysis. It enabled me to catch an air intake leak in the Citabria (high silicon content) that probably would have otherwise gone unnoticed.

[doug8082a]

Having bought a 170 that had sat for a while, I can speak to a few problems that you might encounter. Mine required new bearings and races in all the wheels. It also required to brake calipers since the existing Clevelands were seized and corroded.

The most signficant problem was the least obvious one. The Oil sump on the C-145/O-300 is magnesium. When the oil sits, any moisture precipitates out and settles in the bottom of the sump, particularly in the area forward of the carb. mount around forward the oil drain. This corrodes the sump from the inside out. The TIC170A Service Related Articles Manual (SRAM) has a good article on this - my sump looked just like the photos.

In my case (engine was 450 SMOH), we found it because we had pulled the sump to replace a leaking oil sump gasket. There was about 1/16th (or less) material left at the worst point.

Unfortunately, this is not something you can see from the outside until it's too late and the sump is leaking. It's also a lot of work ($$$) to pull the sump "just to check". I'm not trying to sound like an ambulance chasing lawyer here (no offense to any ambulance chasing lawyers who may be reading this), but it is something to be aware of given how long it has sat. If there was little or no moisture present then you may be fine, but 10 years is still a long time. Up here (in the northeast) that is highly unlikely.

[Paul-WI]

Hi Dan;

Serial #27001 so it was built just before yours. Cool. I did look at the 2 cylinders that where off and there was no sign of corrosion or rust. I will check with my oil supplier about doing oil analysis on the next few oil changes. Does anyone have a good recommendation on an engine heater? The FBO here can install a plug in one that attaches to the oil sump and am thinking about that one. The dragon heater also sounds good but I don't envision leaving it outside overnight.

Thanks again!

Paul

[doug8082a]

Oh yeah, it also needed a new prop due to corrosion on the back of the prop hub, but the previous owner replaced it during his annual a few months before I bought it so it wasn't "my" problem.

[GAHorn]

Paul, in general, oil analysis is only useful when observed over a period of time, and when samples are consistently taken, oil brand/type consistently used, and even the same analysis lab is used. Unless you intend to stay with oil analysis for the remainder of your ownership, it's unlikely that analysis will tell you anything you don't already know: High metals content for a while until the engine settles down again in regular operation.
If it were going to come apart from recent inactivity, it'll likely show up in the next couple of hours/couple of oil screen/filter exams. After that, I'd venture the major risk is past.

[john rogers]

Paul,
I have had two 170's. The first was a 1955 Model (N3428D) and the current one is a 1956 Model (N3499D) Mfg 12-55. They have both had solid axles. You can tell by pulling the nut that holds the main wheels on. A solid axle will have a small hole that will allow a bolt to hold on wheel pants. You can clearly see that the axle is solid. Be sure to put a new cotter key in when you replace the wheel nut or you will have a sad story to tell. The next mod that I have had installed on both my C170's is the P-Ponk Gear Mod. Enjoy your C-170. They are great airplanes (all of them).
John