Engine Ticking?

How to keep the Cessna 170 flying and airworthy.

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ppoeppelman
Posts: 6
Joined: Wed May 13, 2015 1:42 am

Engine Ticking?

Post by ppoeppelman »

Hi folks, I"m new to the 170 Association. My wife and I purchased a 170B serial #20522 back in July. We've Flown a little over 30 hrs since taking delivery, mostly in a training environment, I needed to get my tailwheel endorsement, my wife already had hers. Today we were loaded up in the 170 to get a couple hundred dollar hamburgers. On climbout at max power and 2500 feet, we heard a "ticking" sound? That's the best I can do to describe what we heard. Needless to say we didn't like what we heard, so we turned around, set up a glide to our home airport and landed uneventfully (mostly, more about that later). Oil pressure was steady at about 40 PSI. Oil temperature was in the middle of the green range. There was no actually roughness or vibration felt. The ticking sound went away when we pulled the power. Other things to note, we changed the oil at 30 hours, and there was just one small piece of aluminum in the filter. Oil Analysis came back with aluminum being high, all other metals were normal. (this was this engines first sample, so no history). We have added 7 quarts during the 30 hours. So I think Oil consumption is a little high, but there are some leaks at two of the valve covers, and at least two of the pushrods at the case. When we bough the aircraft it flew from Indiana to SC, and there was not a single drip of oil in the cowling. Compressions at the last annual were 68,68,64,70,67,69. The engine starts and runs great, nice and smooth normally.

I've read through some of the threads, is it possible noise is coming from the lifters? Mags? Where/how would you all start troubleshooting? We are going to get our mechanic involved, but he doesn't work on the weekend.

I said our landing was mostly uneventful, and it was, but taxiing of the runway not so much, the airplane just didn't want to turn. My wife was flying, so we stopped, I got out and noticed the tail wheel was flat. We had picked up a screw somewhere along the way. Luckily we had a spare(in the hangar) and were able to change the tire out and get the airplane back to the hangar. Maybe the airplane was just trying to tell us we weren't supposed to by flying today. Who knows, the engine noise may have prevented us from getting stuck out at our lunch location.

It definitely wasn't our day to fly.

Looking forward to hearing your input.

Phil
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c170b53
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Joined: Mon Apr 22, 2002 8:01 pm

Re: Engine Ticking?

Post by c170b53 »

Phil, for advice, here's step one, don't mess around join the association.
I've had quite a few tailwheel go flat, normally you know it once you slow down in the roll out.
A ticking sound..at that RPM and flight phase, it sounds like you did the prudent thing and you may have a substancial issue at hand. The filter likely will tell the tale.
And most importantly..welcome to a great airplane and community.
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
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edbooth
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Re: Engine Ticking?

Post by edbooth »

Also check for leaking exhaust gasket, sometimes they can make a "ticking" sound.
Ed Booth, 170-B and RV-7 Driver
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Bruce Fenstermacher
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Re: Engine Ticking?

Post by Bruce Fenstermacher »

I'm with Ed. Look for brown exhaust gas leaks around the flanges at the cylinder head.
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ppoeppelman
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Joined: Wed May 13, 2015 1:42 am

Re: Engine Ticking?

Post by ppoeppelman »

Jim, I am already a member.

Bruce, Ed, I will check the exhaust gaskets the next time I get out to the airport.

One more question, is there an easy way to get the cowling off without bending/scraping paint etc?

Phil
n3833v
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Re: Engine Ticking?

Post by n3833v »

Use tape on the spinner.

John
John Hess
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hilltop170
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Re: Engine Ticking?

Post by hilltop170 »

ppoeppelman wrote:
One more question, is there an easy way to get the cowling off without bending/scraping paint etc?

Phil
I second the leaking exhaust gasket but if it is a metallic ticking, lifters come to mind.

Use hex head bolts behind the spinner instead of screws.
Richard Pulley
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
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BeeMan
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Re: Engine Ticking?

Post by BeeMan »

One other possibility for a ticking noise comes to mind. I once had the hinge pin of my right cowling door ('52 170B so I have the big door) work its way forward until it was catching on the back of the prop. As I recall it made a distinct ticking sound but was mitigated by reducing RPM. Engine ran smoothly for the half hour or so it took us to return to home base for an uneventful landing. We identified the cause of the ticking while still flying and you would likely have noticed in flight or after landing so this may be of no help but worth checking if unsure.
ppoeppelman
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Joined: Wed May 13, 2015 1:42 am

Re: Engine Ticking?

Post by ppoeppelman »

Made it out to the airport yesterday to do some inspecting. Pulled the cowling, had the mechanic look over the entire engine, nothing out of the ordinary. We did check the exhaust system as recommended, found a couple of small leaks, but nothing that seemed to be the culprit. On that note, where is a good place to buy a new exhaust gasket set for the O-300D? We also removed the oil filter, cut it open and inspected, the filter was clean. After installing a new filter we accomplished an engine run, all indications and sounds were normal. Maybe we were just hearing things? Or something abnormal coming through the intercom? Strange for sure, definitely going to be very cautious in flying the next few hours.
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n2582d
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Re: Engine Ticking?

Post by n2582d »

Phil, Welcome to the 170 Association! Regarding the clicking noise, you've thrown out a stumper. But there's nothing better for us Lazyboy "experts" than to give advice on someone else's C-170 woes! :lol: Like Richard, my immediate thought was a collapsed lifter but I don't know if you'd be able to hear that in flight.

I'm impressed by how you are solving these issues you're having; working with an A&P, doing an oil trend analysis, and searching here for others with similar issues. As you may know, when you do a search on this website, putting your search words in quotes often helps in narrowing the field when looking for something specific. For example, if you search "exhaust gasket" you will only get results that show those two words together. Without the quotes you would have to weed through results that would include everything to do with exhaust -- CO, pipes, stains, etc. and everything to do with gaskets -- starter gaskets, rocker cover gaskets, silicone gaskets, etc.
ppoeppelman wrote:Other things to note, we changed the oil at 30 hours, and there was just one small piece of aluminum in the filter. Oil Analysis came back with aluminum being high, all other metals were normal. (this was this engines first sample, so no history).
As you and your A&P know the aluminum is most likely from the piston wrist pin plug. I'm sure others will respond regarding other possible sources. Good to hear the last oil filter check came out clean.

I'd be interested to hear what others here think on the various exhaust gasket options. Here's a chart to give you a start on part numbers:
exhaustGaskets.pdf
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Gary
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edbooth
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Re: Engine Ticking?

Post by edbooth »

Exhaust gaskets are available from a lot of sources, Yingling aircraft, Chief, Aircraft Spruce and Specialty to name three. And probably even a local shop if your close to one.
Ed Booth, 170-B and RV-7 Driver
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blueldr
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Re: Engine Ticking?

Post by blueldr »

I assume you have closely checked your wind up clock in the instrument panel. They do a lot of ticking.
BL
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ghostflyer
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Re: Engine Ticking?

Post by ghostflyer »

It also can be a ignition lead outer not earthed out correctly . The noise could be coming through the headsets . I was alarmed when it started with me as I was over tiger country and very low. I went to adjust my headset position and the noise disappeared . Headset back on and the same noise . It was a bad ignition lead.
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canav8
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Re: Engine Ticking?

Post by canav8 »

ghostflyer wrote:It also can be a ignition lead outer not earthed out correctly . The noise could be coming through the headsets . I was alarmed when it started with me as I was over tiger country and very low. I went to adjust my headset position and the noise disappeared . Headset back on and the same noise . It was a bad ignition lead.
I second that. Run the engine with the cowl off at night and look for arcing along the wires.
52' C-170B N2713D Ser #25255
Doug
jrhoa2
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Re: Engine Ticking?

Post by jrhoa2 »

This may sound silly but, is there any chance there was a seatbelt or a purse strap hanging out of the door? That happened to me once while flying a 120. On climb out, I thought that I may have heard some kind of ticking. I swore it sounded like a light engine tick. Like you, I decided to abort the flight.

When I pushed the nose over and started building airspeed, the slipstream must have changed and that seatbelt started slapping the heck out of the side of the fuselage! It scared the crap out of me, it sounded like the airplane was coming apart! It took me about 30 seconds to realize where the banging was coming from. I simply reached over, opened the passenger door, pulled the belt back in, and continued my flight.

It is amazing how hard it is to locate a light ticking sound in a noisy cockpit. I swore my sound was coming from the engine...
James
5729E '59 150TD "BarFly"
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