O-470K starts great but won't run up -RESOLVED-

[Darinh]

Well I started my 180 yesterday for the first time since I have owned it and likely the first time in many years. It fired on 2 blades and ran great below 1200 rpm. Once the temps and pressures looked good I tried bringing it up to 1700 to do a mag check but never made it much past 1300 due to excessive roughness.

I did cycle the mags and on either rt or lt it would kill if I didn't switch back to both almost immediately. I have old slick mags and have no idea when they were last overhauled but I suspect it was more than 15 years ago as my plane has been dormant for more than that. I am getting it back to flying condition.

My hunch is mags for obvious reasons but I dont know a whole lot about them and thought I would ask. I don't know if it seems right that the engine would run fine at low rpms with bad mags but figure plenty of you will. I had someone mention that it could be a plugged jet in the carb. I don't think his is it as I know the last owner had the carb rebuilt in '03 and it has not had fuel through it since.

My engine is old and I am sure I will have addition issues with it with a rebuild most likely in the near future but I wanted to at least chase this issue before giving up.

And lastly... My data plate on the engine says O-470-K-R. Anyone know what the R means? I have had one guy say he thinks it is a K case with R jugs? It was a factory reman back in '65 and has 950 hrs on it.

Thanks

[hotrod150]

Ok is this a joke? Is this what the internet has gone to. You answered yourself. Go get a real person to help you with that mothball before you hurt yourself or someone else. You need more than the screen in front of you. Just saying it the way it is folks.

So you don't know what it might be either?
The questions didn't seem unreasonable to me. It's not like he's asking "how do I start it?".

[hotrod150]

.......My hunch is mags for obvious reasons but I dont know a whole lot about them and thought I would ask....

The local mag shop guy sez you should always check the plugs first-- 90% of the time they are the source of ignition problems. Pull the plugs, clean & gap them, then use a multimeter to check the resistance through them. New spec is 800-1200 ohms, if above 5,000 ohms it's no good. Don't trust those "bomb testers".
Here's a link to his troubleshooting page.
http://www.aircraftmagnetoservice.net/id27.html

[Darinh]

Thanks for the tips Hotrod. I cleaned and gapped the plugs prior to the start but did not put them in a tester. I will do that today.

[hicountry]

A number of things come to mind.......bad caps in mags, mag timing and engine timing, carb problems. Good to start with the plugs and go from there. Capacitors (old) can cause some really weird problems. Bad caps, not failed caps, may not charge at higher RPM. If the engine sat for a long time I would definitely check the caps in the mags and internal mag timing.
Substitute a good mag might help.

[Darinh]

Ok is this a joke? Is this what the internet has gone to. You answered yourself. Go get a real person to help you with that mothball before you hurt yourself or someone else. You need more than the screen in front of you. Just saying it the way it is folks.

I shouldn't even acknowledge this post of yours Maulewaco but I wanted to point out an issue I have seen here and on several forums in the past. You are correct in your question. "Is this is where the internet has gone?" Except the problem is not people asking a perfectly reasonable question in a post but rather insufferable know-it-alls responding with absolutely no worthwhile information at all but rather some kind of insult that in some fashion shows your ignorance. Didn't your mother ever teach you that if you have something constructive to say then don't say anything at all?

Thankfully the rest of the BCP community is composed of reasonable, informative people that are willing to share their experiences with all to the benefit of the aviation community. My opinion is that posts and attitudes like yours add fuel to the fire for all the aviation haters out there and I for one would love to have less fuel on that fire. Maybe think twice before you fire off that next incendiary post.

By the way, where is "Jerk Off USA"? Remind me I don't want to go there.... sounds like people there are a bit frustrated. Just saying it the way it is folks.

[dirtstrip]

Two mags individually showing exactly the same behavior would seem unlikely unless age is the culprit like HC says. Carburetors though, are not redundant and one that has been dry since '03 can still have corrosion or rust issues and that can't be ruled out without inspecting it. Also check the fuel flow rates to the carb to eliminate fuel starvation as the problem. Your hangar queen could easily have several hitches in her git-along.
Proud farm mechanic.

[88H]

Darin:

If you have one of those digitial lazer temperature scanners, you can check each cylinder (if you dont' have a probe on each one) to see if it is a particular cylinder or all 6 that are acting up. I would want to try and see if I could narrow it down to one or all 6.

It does sound like an ignition problem and all the advice on hunting that down is good. If that doesn't pan out consider the intake system.

Just cranked up my 180 after it sat for a long time while performing top overhaul (I am an exceedingly slow mechanic). Had the same problem as you describe, it would start up fine but run rough (through all rpm levels, not just upper end). After checking out the ignition, valves and fuel screens, my mechanic suggested the intake system. While the intake manifold itself was on and torqued correctly, there was a fitting attach point that had a nut loose and air was getting in. Only one cylinder (#1) was affected. Once that was tightened, ran fine.

I have also heard of folks leaving rags in the intake manifold after overhauls.

Might be something to consider if the timing turns out ok.

Good Luck!!

Larry

[wannabe]

Darinh

Roughness is a bit subjective to analyze on-line.
To me roughness on run up and mag checks usually does mean you did not lean well enough during taxi. Sometimes when ya put her away "wet" (forgot to lean for taxi to hangar or tied down) as well as not leaned on the next taxi out. All that will give ya yucky plugs.

Now if by roughness you are stating that the engine is backfiring, then it is likely running too lean.
I have heard that the intake system is tied together with hose sections that can leak air.
The gascolater filter could be plugged, the fuel pump could be tired. Would even check the screens at the tank/bladder outlets.
If it is running lean I hope you have a cylinder head temp guage as you will most likely not hear any detonation.

This is mostly stuff I have overheard or learned on old farm equipment that was built about the same time as our average aviation engines were designed.

Chris C

[Glidergeek]

You might want to purge your fuel system also.

[ccurrie]

Drain and clean the fuel system from the caps to the intake, old fuel and water will do that especially if it sat with car gas in it. Only then would look at ignition.

[mtv]

I would get the airplane to a A/P mechanic who is familiar with that engine type, and pay them to ENSURE the engine is running right and is safe for flight....before you try to fly it, or potentially do more damage.

Not being a smart ass, I have no idea what your mechanical aptitude is. Many folks are pretty handy, but you've got a pretty big investment in that airplane and its engine.

Find a good mechanic, and learn more abou the engine while he/she trouble shoots it for you.

Well worth the $$, trust me.

MTV

[Stol]

Well I started my 180 yesterday for the first time since I have owned it and likely the first time in many years. It fired on 2 blades and ran great below 1200 rpm. Once the temps and pressures looked good I tried bringing it up to 1700 to do a mag check but never made it much past 1300 due to excessive roughness.

Hmmm..

It could be a multitude of things.. but... I have personally seen a exhaust system / muffler, rot and collapse enough to plug the tailpipe during high rpm /run up settings but let enough exhaust gas pass so it would idle good.... IMHO.

[Darinh]

Thanks guys for the tips... I will chase each one rule them out as I go.

I would get the airplane to a A/P mechanic who is familiar with that engine type, and pay them to ENSURE the engine is running right and is safe for flight....before you try to fly it, or potentially do more damage.
MTV

MTV,

I agree and I do have an A&P that is working with me on this. He is out of town this weekend so I wanted to get some opinions. I am not an expert by any means but it is not by first rodeo....I have built 3 airplanes (2 Kitfoxes and a Bearhawk) but I don't work on mags and have never had to deal with an old engine so some of these issues are not my strong points. And I have never had a Continental so their nuances are things I need to learn.

I definitely will not be flying it until is has been thoroughly checked out by my A&P/IA and has been given the go-ahead to fly. As stated previously, I bought the project with the assumption that I would have to overhaul/replace the engine but I would like to tinker with it a bit more.

[A1Skinner]

Maybe it is me. I sure in the hell would not post or ask shit about an airplane on the web. Do it in real life.

Maybe its just me, but I dont see what the difference between asking about a run up issue or me asking if aileron spades or what STOL kit is better. Websites like this are a great resource to help out and get ideas from "real world people". I dunno about you, but I don't have friends that know as much about airplanes as I can get from the combined knowledge on this website. I quite appreciate what Zane created here.

Sent from my Galaxy Nexus using Tapatalk 2

[SixTwoLeemer]

Darin,

Good advice posted above...

If you do end up with mag issues I would recommend Bob Despain @ Precision-KBTF. He can IRAN the internals and won't miss anything. I agree with the plugs and carb being suspect. I just went thru my plugs completely and one wouldn't test for some reason. Well the reason was a somewhat invisible carbon bridge but I only found it after the test. Looked perfect to the eye.

Bob is a carb expert too.

Good luck.

[Terry]

Maybe it is me. I sure in the hell would not post or ask shit about an airplane on the web. Do it in real life.

Maybe its just me, but I dont see what the difference between asking about a run up issue or me asking if aileron spades or what STOL kit is better. Websites like this are a great resource to help out and get ideas from "real world people". I dunno about you, but I don't have friends that know as much about airplanes as I can get from the combined knowledge on this website. I quite appreciate what Zane created here.

Sent from my Galaxy Nexus using Tapatalk 2

Just another mall owner wishing he owned a Cessna.

[Darinh]

Darin,

Good advice posted above...

If you do end up with mag issues I would recommend Bob Despain @ Precision-KBTF. He can IRAN the internals and won't miss anything. I agree with the plugs and carb being suspect. I just went thru my plugs completely and one wouldn't test for some reason. Well the reason was a somewhat invisible carbon bridge but I only found it after the test. Looked perfect to the eye.

Bob is a carb expert too.

Good luck.

SixTwoLeemer,

Thanks for the advice...I have had Bob do work for me in the past including overhauling all the internals on my last O-540. I didn't know he was a mag guy though. My mags are the old 662 slicks so I need to upgrade them anyway regardless so that along with checking the carb and fuel system is in order.

[oldtech]

I'm in with Stol. I would check the mufflers for restrictions. also, what is on it for an air filter? maybe it's choking. Doesn't sound to me like ign. carb maybe??

[Darinh]

I'm in with Stol. I would check the mufflers for restrictions. also, what is on it for an air filter? maybe it's choking. Doesn't sound to me like ign. carb maybe??

Exhaust is good - no restrictions. It has a new airbox and bracket air filter so that should not be the issue. I am going to go through the fuel system today to verify no restrictions and then it will be on to the carb. Ignition will be the last item to be addressed.

If I had the funds I would simply ship it off to Steve Knopp..... Maybe next year.