My new engine is harder to start

Your lady just doesn’t like the cold, try again in the spring :D

I’m experiencing a similar issue except mine just doesn’t turn the prop 1 inch. Probably a user error, the lady likes to be turned a certain smoothness and I guess I’m not figuring it out yet. Lol
 
Ted said:
See my previous post about Aztec aluminum cables looking like they caught fire. That usually is because they caught fire.
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Thanks, just saw it after I posted. I considered buying this particular Aztec last year, the price he was looking for was one of those 'too good to be true' but the amount of work that would go into it turned me off to it, plus there are decent condition ones already out there. That's a good point though, something to keep in mind for the eventual purchase, should it happen
 
I have had non-aviation engines do this. I've seen it mostly (i think) because the battery is getting weak...but I have seen some engines that do it sometimes...just my theory, that it seems like it depends where it stopped in the rotation relative to a compression stroke. If too close, the starter doesn't have enough rotational angle to get the flywheel moving and it has to fight through the first compression stroke..... then after it starts moving it has enough inertia to keep going.
 
We had a diesel engine that could keep the valves open to disable the compression and it was much easier to turn that way then you pop them closed and it would start up
 
I second, third, fourth or whatever the count is to check all connections. I had the same problem a number of years ago, and it ended up being the ground connection at my firewall. The connection looked good but when I gave it a good tug, the entire ring terminal broke off around the attach bolt…
 
As a simple check, you might try jump-starting it with another battery or a power cart. If it starts easily you have a weak battery. If not, go on a bad connection hunt.
 
TomRV4 said:
I second, third, fourth or whatever the count is to check all connections. I had the same problem a number of years ago, and it ended up being the ground connection at my firewall. The connection looked good but when I gave it a good tug, the entire ring terminal broke off around the attach bolt…
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I have found the engine mount painted so thoroughly that its contact with the firewall is compromised. Anytime I reinstalled a rebuilt mount I cleaned the paint off the ends of the bolt lugs so as to get good contact at the firewall and bolts/nuts. Then I have found the ground strap between the engine and mount loose, dirty, oily, the clamp in the mount over top of the paint, the end bolted to a painted surface on the engine, and so on. Electrons don't care to travel through oil and grease and paint and dirt, and like I posted earlier, it only takes a tiny resistance at starter current levels to kill the whole system. Most ground straps are just braided plate copper wire, crimped into a tinned copper sheet terminal, and crap creeping in there also adds resistance.

Other stuff happens when there is resistance between the engine and airframe. The alternator is pumping electrons into ground. If its ground connection with the firewall is poor, those electrons are looking for easier paths, and some of them sneak into the thermistor that drives the oil temperature gauge. It has the effect of boosting the current flow through the thermistor and gauge and drives the oil temp indication way up.

Little stuff matters.
 
Half Fast said:
As a simple check, you might try jump-starting it with another battery or a power cart. If it starts easily you have a weak battery. If not, go on a bad connection hunt.
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That won't always tell you anything. Some of the ground service connection systems bypass the master contactor, and that contactor may be part of the problem. It might start fine, and then you buy a new battery and it still doesn't start properly.

Cheapest fix is still the expensive mechanic, the one who knows how to troubleshoot electrical systems.
 
I'm
Dan Thomas said:
That won't always tell you anything. Some of the ground service connection systems bypass the master contactor, and that contactor may be part of the problem. It might start fine, and then you buy a new battery and it still doesn't start properly.

Cheapest fix is still the expensive mechanic, the one who knows how to troubleshoot electrical systems.
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True if you use the ground power connector rather than jumper cables to the battery connections.
 
What kind of battery does it have? I run two PC680's in the Venture in place of a Gill 24v. The 680's definitely don't have the same cold cranking amps.
 
Half Fast said:
I'm


True if you use the ground power connector rather than jumper cables to the battery connections.
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Even that doesn't tell the truth. Connecting another battery in parallel doubles the amperage capacity, reducing the battery's voltage drop caused by the battery's internal resistance. Two resistances in parallel have a much lower resistance. The jumper cables can thereby mask the problem.

Sure, it might be worth trying. A more accurate check would be to borrow a known good battery of the same amp-hour capacity and put it in the airplane, eliminating the original battery altogether, then try it.
 
Dan Thomas said:
Even that doesn't tell the truth. Connecting another battery in parallel doubles the amperage capacity, reducing the battery's voltage drop caused by the battery's internal resistance. Two resistances in parallel have a much lower resistance. The jumper cables can thereby mask the problem.

Sure, it might be worth trying. A more accurate check would be to borrow a known good battery of the same amp-hour capacity and put it in the airplane, eliminating the original battery altogether, then try it.
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Increasing the ampacity and reducing battery resistance is the whole point. That will show whether the battery is the limiting factor. It won't solve a resistance issue in a contactor or in a bad connection. If it's still hard to start, then the problem is somewhere in the wiring.

Yes, swapping the battery is worth trying, if a battery is available for a trial.
 
People will poo-poo this.
I never get in a plane without pulling the engine through 6 times.
Habit, superstition, waste of time, genius. Who knows.
But, I have occasionally discovered some things while doing this.

Good luck with the new ride.
 
I agree with the majority of the posters.. It's electrical. Weak starter or battery and possibly cables between said components.
 
Zeldman said:
Like a hot mag that previously was not hot.??
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yes I have,

But typically I only pull the prop thru prior to a cold/non-preheated start i.e. < 32 degrees, or an engine that hasn't ran for a few months.
or like in my Hot Mag case it was Champ with no electrical system, pulling it through is how you prime it for start.

Is a bit interesting to walk back to the cockpit thinking did I leave the mags on? look inside and see the Mag switch in the off position while the engine is sitting there idling.

As long as you treat pulling it through with the same precautions you should when hand propping, a Hot Mag is a non-issue.

Brian
CFIIGI/ASEL
 
Dumb question/suggestion:

What if Bryan threw a battery charger on it for about 4 hrs before the next cold start. If it blader over very fast with no hesitation - would that be enough to say its the battery and save a bunch of probing firs
 
I have a light weight starter on the Warrior and Same issue we have tried to figure out for four years…sort of hangs for a second on the first jug and then spins and starts…new batteries…cleaning cables…cold weather or hot…-always happens on the first start of the day. Second start and after swings it no issue..
 
Sinistar said:
Dumb question/suggestion:

What if Bryan threw a battery charger on it for about 4 hrs before the next cold start. If it blader over very fast with no hesitation - would that be enough to say its the battery and save a bunch of probing firs
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I have a trickle charger. I will do that and report back
 
midwestpa24 said:
Our Comanche used to be that way until it got a new lightweight starter (Skytec I think). You can nearly taxi with that darn thing now.
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same in my Cessna 140! I think I could use it to stretch a glide after engine failure! :)
 
SixPapaCharlie said:
Former plane had the O-320. I hit the starter and it turned freely and fired up with no issue.


New plane has a O-540. I hit the starter and it starts to spin but then has moments of hesitation between the spinning portion of startup.

It definitely takes longer to start but mostly it feels like the starter is barely strong enough to turn the prop.

does this sound like a starter thing, a battery thing, or is is just a bigger engine thing?

Watch this dude's. Notice on the first spin, it stops briefly before doing the spinny part.
What is happening there. Mine does that. I prefer it t just turn over a couple times, not have that hesitation, and start up.

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As to whether it is a bigger engine thing, what were your experiences with the bigger engine in the Cirrus?
 
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