Engine Ticking sound under stress

Alain1

Alain1

New member
Got the crate back in the air yesterday after 2 and half month sleeping.
Old Franky 165 starts good and run smooth, but when going full power for take off i get a ticking sound like a lifter
on an old chevy 350 c.i.. When I level and bring power back, it goes away. If I set high R.P.M. in level flight, nice and smooth.
Lower r.p.m. again, nice and smooth. only when climbing with full power or on take off I get this sound. When under high m.p. or high demand.
Could this be the fuel pump? Stuck valve would give me rough engine wouldn't it ? Also noticed fuel pressure a bit lower. Used to be 4 1/2 to 5 lbs
It shows 3 but had the fuel press gauge redone with the two other indicators in that instrument. Pumping the wobble pump while flying does bring it up.

I had a similar fuel pump on a GM car a long time ago and before quitting it gave me a similar sound.

Alain.
 
Alain, I hope your ticking problem has gone by now. I had the same problem, years ago, in a Franklin.....but it was noticeable only at low RPM. Turned out to be a gear lash problem. Engines that sit tend to get sticky. I think you have a valve train 'hangup,' somewhere . As much as some folks laugh at this topic, I am a believer in Marvel Mystery Oil.........MMO. Put a quart in the oil...put at least 8oz in a tank of gasoline. Fly hard for an hour. If the noise is still there when you get home, you probably have a mechanical issue. Keep me posted .
 
BTW, Aircooled Motors stated in their pre-war manuals that a top cylinder lubricant [MMO] , 'may be beneficial.' In their postwar manuals, unleaded fuel is specified.
 
Dan, you read my mind or what ???!!!

Saturday I went up for 30 min, this is when I found that noise. That's why I did not stayed longer.
Sunday I went back, put it a quart of Marvel added to the 6 quart that was in there, and ran for about 40 min. over the airport. Noise still there.
I am letting it sit for the week, maybe Marvel will soften some gooo somewhere and I will go back to give it another hour.
If noise still there, I will flush it and put in new oil. I am due anyway. Then it will be investigation time if not fixed.
Again, donno if anyone ever had a problem with these mecanical fuel pump, I am coming back to it because like I mentionned, I had a similar pump in a car
that made the same sound. Since my fuel pressure is a little down from last fall...What make me say that is that it's only when the engine is gulping gas at
its max that the sound occur. On take off run or on climb.At idle, at low or high rpm but inlevel, no noise. Only under hi m.p.
And it really run smooth. nice idle no noise, 2500 level, no noise and smoooth. Weird.

Thanks for letting me know about the Marvel Mystery oil, I am happy I am not alone...

Alain.
 
Alain, the 3psi. indication is very normal in this installation. I'll bet Keystone accurized your guage! After a week, fly more. If the sound persists, Take a 1"x 30" dowling, put one end to your ear-put the other end on various parts of the engine. I'd check the fuel pump and in the case area where the cam followers live. Do this at about 1000rpm, with a trusted friend at the controls. Good lord, be careful of the prop! This is an old auto mechanics way of finding a source of noise.
 
After all this being unsatisfactory, I'd check compression and maybe pop the valve covers off to check the clearances and the condition of the springs. This area is so noisy during operation that the dowling trick doesn't work here. Good Luck.
 
Greg Lucas has parts to rebuild the fuel pump. He can send you the parts or rebuild it for you for about the same price.

Kevin
 
Sounds like a good plan Dan. I will follow your advise. I'll keep you posted.

Thanks for the contact for the fuel pump Kevin. We'll see how it goes. If this is the problem I will ship him the pump.
You guys are great.

Alain.
 
That reminds me, I actually used that dowel trick on that problem fuel pump on the car I was mentionning above. And a few time after that on other stuff. Boat Out board engine I think. works great. It was actually a long Snap-On screwdriver. was about 28 in. long i was using as a pry bar. was perfect for that too!
 
Alain, Keep up us posted on your engine.Make sure the noise doesn't come from your tachometer or the tach drive assembly.
 
So, here I am, flown about 1.5 hrs last week, sound went away after dipping in Marvel Mystery OIl for the week. But then came back when I did a touch and go, on the climb with ball to the wall and lower r.p.m. on climb,
went away again when lowering the nose and throttle back to 2400 and higher r.p.m. in level with no stress on it like in climb.

Will change oil now, it is due, and will check valve clearance during the annual inspection next week. I really donno where this come from but I remember that cylinders were new (not even 5 hrs) when I bought the crate and were never adjusted since, got about 30 hrs now. still hope to get rid of the noise at low cost. :roll:

Alain
 
For the last 2 year, been buring a mix of 100LL and super unleaded.
Not sure if it's the timing, was running fine for 2 years and suddenly aftertaking it our after 2 month sleeping it started.
getting better now but going thru annual inspection next week and we'll check the valve/rocker clearance.
Like I mentionned before they are pretty new cylinders and might need a litte bit of re adjust.
 
Alain, That engine was certified to run on unleaded 80 octane fuel. No sense in paying extra for 'super.' Yes, check the timing........also, make sure that noise doesn't come from the tach or tach cable.
 
Thanks for the heads up Dan, I will check these, timing and tach cable. And thanks for the fuel update!

Alain.
 
Ok guys, crack a beer open and prepare to laugh at me,: loose plug on lower no. 6 cyl... :shock: :oops:
Under high m.p. it would leak and produce that sound. :roll:
 
Don't get too embarrassed, Alain.

It wound up being a useful and interesting thread.

I now know of close to a dozen things to look for if something like this happens on my plane.

Dave York
 
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