The International Cessna^® 170 Association

OK – here's the update: back to the airplane today with my engineer, here's what we found. One nut not installed on the cylinder stud of the number 4 intake stub. Looks like the exhaust got put back on and covered over the intake stubs before we double checked our work back there. Fixed that, checked torque on all the others, ran the shop vac and soap bubble pressure test, all good, and on run-up no more squeal! Yee haw.

Did another break-in flight, and the only bad news was that the oil leak I have been chasing for three years, and which all this work was supposed to resolve, is still there. We replaced two cylinders to deal with bad rings that were likely pressurizing the crankcase, and new real gasket pushrod tube conversion for that whole side. I am going to go back in and re-do the pushrod housing gasket on that number six cylinder. On the other hand, the engine work is all signed off, we did an annual at the same time and so at least we are back in the air after two months, just have to keep wiping some oil.

I have heard that the reason that Continental motors never got into the computer business is because they couldn't figure out how to make one leak oil.

Thanks for all the advice!

Bikerboy6 wrote:... I have heard that the reason that Continental motors never got into the computer business is because they couldn't figure out how to make one leak oil. ...

That's the funniest thing I've read all day; I'm glad I didn't have mouthful of beer!!

I've got 450 hours on my O300C since overhaul and the only thing that leaks is the quick change sump plug. I check religiously making sure oil is in the engine. Maybe Eric did something wrong when he overhauled the engine???

My Continental does not leak oil. It has a pretty cool feature that sprays a metered amount of warm anti corrosion fluid about the engine compartment, firewall and belly skin. Plug up that feature and you'll be complaining about rusting hardware.

canav8 wrote:

hilltop170 wrote:To test for an intake leak, remove the carb heat hose from the muffler and duct tape it to a leaf blower. Turn on the carb heat and turn on the leaf blower. Spray soapy water from a pump bottle all over the engine. Any leak will blow bubbles. An intake leak will usually cause at least one cylinder to misfire due to being too lean and the engine will not idle smoothly.

Richard, will it also show the black sooty signs as Doug showed in his picture? Not sure this trail is hot. Doug

Doug, I don't understand the questio.

Our Continentals keep our tail springs lubed so they won't rust But they sure are smooth

hilltop170 wrote:

canav8 wrote:

hilltop170 wrote:To test for an intake leak, remove the carb heat hose from the muffler and duct tape it to a leaf blower. Turn on the carb heat and turn on the leaf blower. Spray soapy water from a pump bottle all over the engine. Any leak will blow bubbles. An intake leak will usually cause at least one cylinder to misfire due to being too lean and the engine will not idle smoothly.

Richard, will it also show the black sooty signs as Doug showed in his picture? Not sure this trail is hot. Doug

Doug, I don't understand the questio.

Lol, I wondered where this post went. It is not supposed to be on this thread but actually another. This belongs on Jasons sooty exhaust stacks thread...lol I love stray electrons.

A happy landing. Went back and pulled the cowls (I'm getting very fast at this, all 30 screws) and found that all of the pushrod housing covers had eased off a bit loose during the breakin flights. Was able to get small ratchet way in to the back and retorque them all, two 40 minute flights now, and it's looking clean under there. Here's hoping!

Last annual was 8 months ago, we just put two new jugs on - did annual inspection while we were all apart. Anyone else think it odd (or even illegal) that my AME chose to not do a compression test? I'm going to go get one for my own satisfaction, but I find this highly odd. His reputation not grand to start with - I am at a small field with no real shop onsite.

Bruce Fenstermacher wrote:My Continental does not leak oil. It has a pretty cool feature that sprays a metered amount of warm anti corrosion fluid about the engine compartment, firewall and belly skin. Plug up that feature and you'll be complaining about rusting hardware.

I like this! Well done. You should set up an STC.

Bikerboy6 wrote:... - did annual inspection while we were all apart. Anyone else think it odd (or even illegal) that my AME chose to not do a compression test?

Yes, at a minimum he should have a checklist to cover the applicable portions of Part 43 Appendix D. In there (d) 3 calls for a compression check.

For those following this, I believe Bikerboy is a Canadian and as such there should be a statement by the Aircraft Maintenance Engineer (AME) that maintenance was performed IAW CARS (Canadian Aviation Regulations) Standard 625 and include the applicable appendixes most likely B + C . "B" is for the maintenance schedule which will include items such as your compression check and "C" will be your out of phase items such as your ELT, possibly your prop, your transponder and a check of your mechanical tach.
Really, the compression check is a check of what's leaking, whether its the intake valve, exhaust valve or a crack in the cylinder. You really want to find out if you have a small external leak from a cylinder before you find the much more obvious large external leak.
For those south of the 49Th what must be completed in the documentation (release statement) to make the plane legal?

n2582d wrote:

Bikerboy6 wrote:... - did annual inspection while we were all apart. Anyone else think it odd (or even illegal) that my AME chose to not do a compression test?

Yes, at a minimum he should have a checklist to cover the applicable portions of Part 43 Appendix D. In there (d) 3 calls for a compression check.

Well l Gary that is assuming the AME is in the US or having to follow US FAR's. Something clues me in that someone called an AME, wrenching on an airplane is not operating under US code.

And do I find it odd that a qualified mechanic not perform a compression check on an airplane during annual. In short, no I don't. At least a compression check with compresses air and gauges like you may have witnessed. You see many mechanics have the experience to be able to pull a prop through and know if an engine will pass a compression check. There is a pretty wide latitude for what passes a compression check and what does not. Chance are the AME did a compression check. You just didn't notice.

In the US there are various FARs that guide how maintenance is to be performed. The check list Gary alluded to is part of one. That will lead to a plethora of maintenance manuals which must, at least, be available, if not consulted, in order for the maintenance to be done. One of those manuals or instructions will be the exact tooling and procedure to be used to perform a compression check. Did you know it is a different procedure for a Lycoming vs Continental? I'd bet that if there was a way to absolutely track such information, many many more of the compression checks done are not done by the book than those that are.

Of course some would say there is a way to track such info and that would be the log entry that says it was done correctly when that entry is required.

I'm sure you don't intend to rat out your AME. You probably just where not there to see him perform that operation.

BTW performing a compression check on the two redone cylinders is useless at they are not broken in.

Helpful info Bruce - happy to hear advice on when a post break-in comp check for those new cylinders would be most useful. Certainly not intending to cause any grief for the guy. Just its my butt in the seat up there over bush and rock most of the time, and I'm eager to have thorough work done. I got behind on carb heat on a hot sticky day last summer and for the only time in 26 years had to dead stick in - found the only flat piece of road for 10 miles either way. Lucky. They call this engine the 'ice-maker', right?

I have all of the SB's, manuals, inspection sheets, and ad's , and am aware of the newer TCM procedures and equipment. Though I have yet to talk to an AME up at the field here who knows of it. So, no master orifice tools or bore scopes to be found. (I know it only has the force of an advisory).

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