I drool over the C421 all the time and spend far too many hours on Controller window shopping them. However, threads like these remind me of the level of commitment required and how many potential problems can occur. I'm pulling my hair out over regular mx issues on the Seneca today. I can't imagine my frustration owning a C421.

Still...

Frustration is about the same but when working correctly he is flying in a 421 and you are flying in a Seneca.

There is not a lot of frustration if you go through the 421 throughly and fix or repair everything that needs it on the first annual. Then stay on top of the MX and repair or replace some parts on a schedule. First annual on most 421's should be 40 to 50,000 dollars unless you buy a really good one. Direct operating cost based on 100 hours per year about 650 to 750 dollars per hour.

Just went through that first annual and concur with the price tag to fix all known issues. Sure hope maintenance is a lot less this year...

That said the right engine starter went out only three flights after annual! I read somewhere the starters should only be run max ten seconds then rested for one minute to cool off.

Cool weather starts have been an issue though haven't counted how long took to start sure could have been longer than ten seconds. I usually prime four or five seconds then sit for one minute then crank the starter. Often it will fire quickly but then stop firing before I can tickle the primer. Then I continue priming and finally it will fire and start. Two questions for the 421 experts. What is good cool/cold weather starting technique to consistently get a good cool/cold weather start? Also is ten seconds the max to run starters? Cold weather starts have been one of the only real frustrations on the 421C.

Thanks,
Byron

Why do you wait one minute before engaging the starter?

Byron I don't know how cold is cold for you . On mine a cold start is prime to about 10 gallons on FF. Throttle closed and engine should start with about 3 blades if the mags are timed properly. I suggest you contact Peter Danto about the correct set up.

OK that's quite a bit more priming than I have tried. Usually after four seconds fuel is running out of the engine but ff is about three or four. Cold is below 50, I have a heated hangar but sometimes might have to start below 40 if I'm out and can't plug the engines in. Thanks for the info I will try that.

Fuel takes longer to evaporate in cold weather so waiting allows the mixture to get right. In the Cirrus IO-550 waiting one minutes is about right and usually works well.


Byron

I fly into cold areas weekly during winter. I never wait after priming and have had no issues starting any of my pistons. My GTSIOs did need longer primes in cold weather.

Have you tried the book start? Hold primer and crank, release both when it starts?

In colder weather I'll prime for a few seconds before hitting the starter, but I won't vary the procedure too much for cold weather.

That being said, if it's really cold (sub 30) then the GTSIOs really like a pre heat.

Robert

I concur, works every time...except maybe a hot start where you may need to pull the mixture back and push the throttle forward for about a second.

On most hot starts I use a quick shot of prime and crank, moving the throttle forward until I hit the sweet spot and the engine fires. I let the RPM climb to over 1,000 and keep it there,turn on the low boost pump and start the other one. Works 9 out 10 times and if it doesn't I use the book procedure.

That sounds inflated for a 421, but if that is true, you could be flying a turboprop and enjoy superior reliability and 300 knots for that kind of money or less.

Mike C.

What a novel idea. As I've struggled with cold weather starts I chatted with my very knowledgeable 421 instructor who did present this as an option to what I described earlier but said both were ok. I'll make the "book" version primary.

Hot starts are a snap with the following procedure:

Mixture at cutoff
Boost(aux) pump on
Immediately hit starter
Smoothly bring mixture up
Engine will start every time.

Note no prime.

I love the 421C, can load my family of six up with luggage and fly three hours. So much capability. My wife loves it, loves pressurization, loves air conditioning, loves taking the whole family. It is very reliable.

Thanks for your help,
Byron

Don,
We have definitely dealt with some maintenance issues in our first year of ownership. However, I can’t think of one that is specific to the 421. A couple were pressurization, several engine issues (unrelated to the GTSIO), and a couple avionics issues. We tried to buy near the top of the market to decrease the potential problems, but we probably rushed it a bit...maybe a lot. Patient shopping is not a gift Dad or I possess.

On the other hand, in the 8 months since our initial training the plane has been to the west coast twice, the east coast several times, the northern UP a couple times, south Florida, and many other inland destinations, in about 125 hrs of hobbs time. http://flightaware.com/live/flight/N421EE/history

I can think of one time we had to change a scheduled trip for maintenance, and I spent several hours over the last two weeks in FL dealing with these recent issues, but overall the uptime or dispatch rate has been pretty good for the first year of ownership. Really frustrating at times but normal for the first year I think.

Also, I’ve seen you mention TAS being close to you…that is huge. They’ve been really good to us. I talked with Tony about the crap that was found in the nacelle tank, which they replaced in October. A few hours later he called back to say they would pay the entire maintenance bill at Marco Island. They’re probably the least likely culprit and there’s no way we can take him up on it, but I was impressed with the offer.

Jack,

I have had poor success with the Ram spring-loaded clamps for the inductions hoses. My memory is that when at FL210 and max allowable MP, the induction system is about 10 psi above ambient. I have gone back to the TCM clamps, PN AN737TW82.

The other problem is that the fuel line support that goes under the induction hoses tends to create a gap - and or to stretch the hose in that vicinity. I have gone to replacing those hoses whenever the induction manifold had been removed. I use the Ram hoses PN 1125-2. You may also try to relocate the fuel line supports so that they are clamped to the OD of the hose using a separate clamp. You can also slice a section of an old hose and use it around the tube as the support - i.e. clamp in an area where there is no induction pressure or suction.

For the metal induction tubes coming off the cylinder, these frequently get mangled by mechanics using screwdrivers to force the hose loose. I suggest replacing all that are mangled. All are the same PN 639323, except for #5 which is PN 641520.

The gasket between the metal induction tubes and the cylinder head almost always breaks when work is done on the tubes. Replace these every time, PN 649950.

Unless your intercooler has an induction air temp probe, there is a pipe fitting the the forward top that is good to use as a pressure test port for induction leaks. Another way to check induction leaks is to use something like the attached photo to go on the intercooler inlet. Be very careful with the clamps that go the duct between the turbo and the intercooler. Very easy to mangle these. The clamp is PN AN737TW114, the sleeve (expensive part) is PN 630881-1

For upper deck air leak checks, pull the upper deck air line off somewhere around its source downstream of the turbo and attach an air fitting. If there is an upper deck air leak near the injectors, gas would rather exit through the leak than go into the cylinders.

Finally, when you are in there working on this stuff, check every fuel injector line from the sypder to the cylinder head. I can almost guarantee that you will have chafing on several of them. Also check the large fuel supply line going to the spyder for chafing.

If you have the 7th nozzle solenoid (421 SN 1000+), check those lines carefully for chafing.