Firewall Forward Rocket Overhaul Cost Breakdown

[snowds]

Just overhauled my Rocket.  It was around $57K, all in ($37K in engine overhaul, and another $20K in removal/installation).  That included an annual.

Question: If you have a really smooth running Rocket, please do me a favor: after a flight, before shut down (i.e. engine hot), check your fuel flow at 1,000 RPM, and let me know what it is (full rich mixture).  Also, please check the fuel flow at 17" and max rpm while in flight, slowing down on final.  I would be hugely appreciative of these numbers.  Getting the fuel system set up properly after the overhaul has taken some work; make sure to exactly follow the directions in the STC documents.

[aviatoreb]

58 minutes ago, snowds said:

Just overhauled my Rocket.  It was around $57K, all in ($37K in engine overhaul, and another $20K in removal/installation).  That included an annual.

Question: If you have a really smooth running Rocket, please do me a favor: after a flight, before shut down (i.e. engine hot), check your fuel flow at 1,000 RPM, and let me know what it is (full rich mixture).  Also, please check the fuel flow at 17" and max rpm while in flight, slowing down on final.  I would be hugely appreciative of these numbers.  Getting the fuel system set up properly after the overhaul has taken some work; make sure to exactly follow the directions in the STC documents.

I'll be flying Sunday and I'll let you know.

Who did your engine?

What did you include in that 57k all in?  Prop?  Exhaust? Engine cage?  Engine lords mounts?  Or is that mostly r&r and engine and hoses and all?

[snowds]

53 minutes ago, aviatoreb said:

I'll be flying Sunday and I'll let you know.

Who did your engine?

What did you include in that 57k all in?  Prop?  Exhaust? Engine cage?  Engine lords mounts?  Or is that mostly r&r and engine and hoses and all?

Ok, thanks.  The flows are really close, but there's still a little bit of roughness around 16" (in flight-everything checks fine on the ground).  My prop was in good shape, so the pricing did not include any prop work; same with the exhaust.  It did include rebuild of the engine mounts, and overhaul of all accessories except for the alternators.  Zephyr did the engine, and they have really stood by their work with the fuel system issues.

[aviatoreb]

8 hours ago, snowds said:

Ok, thanks.  The flows are really close, but there's still a little bit of roughness around 16" (in flight-everything checks fine on the ground).  My prop was in good shape, so the pricing did not include any prop work; same with the exhaust.  It did include rebuild of the engine mounts, and overhaul of all accessories except for the alternators.  Zephyr did the engine, and they have really stood by their work with the fuel system issues.

Aha - well I will be very interested to hear later how your Zephyr engine is going for you since that will likely be the shop I might use when my time comes.  Last year I decided to shop- pre-pick a shop since then I was at 1250 hrs and as we all know these engines might decide its time before we like, and I didn't want to find myself shopping in a hurry.  So I decided to shop at my leasure  through the various shops and Zephyr is likely the winner.

Your cost is a tad higher than I would have guessed since I was guessing 55k for engine, accessories, but also including exhaust.  But still quite in the ballpark.

Your engine roughness - at rough at all other power settings besides 16''?  How about below 16''?

All I can guess is that at 16'' could you be descending so that then there is not any power being pulled from the prop but rather it more braking?  Maybe try 16'' but be sure to arrest descent as much as reasonable to really pull power from prop just to see what happens?

[Omega703]

8 hours ago, snowds said: Ok, thanks.  The flows are really close, but there's still a little bit of roughness around 16" (in flight-everything checks fine on the ground).  My prop was in good shape, so the pricing did not include any prop work; same with the exhaust.  It did include rebuild of the engine mounts, and overhaul of all accessories except for the alternators.  Zephyr did the engine, and they have really stood by their work with the fuel system issues.

Aha - well I will be very interested to hear later how your Zephyr engine is going for you since that will likely be the shop I might use when my time comes.  Last year I decided to shop- pre-pick a shop since then I was at 1250 hrs and as we all know these engines might decide its time before we like, and I didn't want to find myself shopping in a hurry.  So I decided to shop at my leasure  through the various shops and Zephyr is likely the winner.

Your cost is a tad higher than I would have guessed since I was guessing 55k for engine, accessories, but also including exhaust.  But still quite in the ballpark.

Your engine roughness - at rough at all other power settings besides 16''?  How about below 16''?

All I can guess is that at 16'' could you be descending so that then there is not any power being pulled from the prop but rather it more braking?  Maybe try 16'' but be sure to arrest descent as much as reasonable to really pull power from prop just to see what happens?

My rocket has always ran rough when in idle on final (flown it about 350 hours now). I attributed the roughness to the reason you give above- the prop is braking. I've had no issues with the engine.

[Bravoman]

I don't have a rocket(have a bravo) but I thought up until a couple of days ago I was going to need an overhaul sooner rather than later due to what we thought was excessive metal in the oil filter on my second to last oil change. We decided I would fly it for a about 10 hours and recheck it. Have done that and it looks much better but have sent out for an oil analysis to get a detailed look. Have also shopped for overhaul shops just in case and narrowed it down to Penn Yan and Zephyr. 

My question really is whether it is better to have an MSC do the removal and install or bring it to the overhaul shop for that? That isn't an option with Penn Yan but zephyr does offer that service. The latter shop is closer to me and I do see the potential benefit of having the overhauler hang the engine to make sure all is well before it leaves the shop. Certainly with an aftermarket set up like the Rocket I can see the benefit of this due to paculiarities with fuel flow set ups etc that may not be so much of an issue on a non modded aircraft like mine. On the other hand I recently read an article by Don Maxwell about how Mooneys need to have the engines properly shimmed when installed and that there is a Mooney specific way of doing this. My concern is that the overhaul shop might not know how to do this properly even though they might try to assure otherwise, and it would be a real pain to have to get the shimming straightened out if it was done incorrectly. 

Any thoughts on this would be appreciated.

[ArtVandelay]

I would talk with the shop and ask them if they have any experience with Mooney engine mounts.  I would also take pictures before, so if something doesn't look right, you can point out what it should look like.

[Mcstealth]

On November 22, 2015 at 4:44:05 AM, Bravoman said:

I don't have a rocket(have a bravo) but I thought up until a couple of days ago I was going to need an overhaul sooner rather than later due to what we thought was excessive metal in the oil filter on my second to last oil change. We decided I would fly it for a about 10 hours and recheck it. Have done that and it looks much better but have sent out for an oil analysis to get a detailed look. Have also shopped for overhaul shops just in case and narrowed it down to Penn Yan and Zephyr. 

My question really is whether it is better to have an MSC do the removal and install or bring it to the overhaul shop for that? That isn't an option with Penn Yan but zephyr does offer that service. The latter shop is closer to me and I do see the potential benefit of having the overhauler hang the engine to make sure all is well before it leaves the shop. Certainly with an aftermarket set up like the Rocket I can see the benefit of this due to paculiarities with fuel flow set ups etc that may not be so much of an issue on a non modded aircraft like mine. On the other hand I recently read an article by Don Maxwell about how Mooneys need to have the engines properly shimmed when installed and that there is a Mooney specific way of doing this. My concern is that the overhaul shop might not know how to do this properly even though they might try to assure otherwise, and it would be a real pain to have to get the shimming straightened out if it was done incorrectly. 

Any thoughts on this would be appreciated.

Certainly is easy to understand your concern. It is easy for one to say go to an MSC. I say educate yourself like you were going to the doctor. Know all the questions and ask them to your shop and get a feel for what they say. If they don't answer you in a way you feel comfortable, go to the next.

[snowds]

Finally got the overhauled Rocket running perfectly smooth at low power settings (16 inches and below, on final).  It is critical that the fuel flow set up be done exactly according to the Rocket STC document (and not the Continental service bulletin); the fuel system builder swore there was no way the engine would run properly being set so lean at the low-end.  Against his intuition, the A&P took two full turns on the low end fuel flow screw, and it fixed the roughness.  Ridiculously smooth now.  He had never set an engine so lean that there is no RPM increase when leaning on the ground at 1,000 rpm, but that's what the STC called for, and that's what ended up working.  When all else fails, read the directions!

[Mcstealth]

37 minutes ago, snowds said:

Finally got the overhauled Rocket running perfectly smooth at low power settings (16 inches and below, on final).  It is critical that the fuel flow set up be done exactly according to the Rocket STC document (and not the Continental service bulletin); the fuel system builder swore there was no way the engine would run properly being set so lean at the low-end.  Against his intuition, the A&P took two full turns on the low end fuel flow screw, and it fixed the roughness.  Ridiculously smooth now.  He had never set an engine so lean that there is no RPM increase when leaning on the ground at 1,000 rpm, but that's what the STC called for, and that's what ended up working.  When all else fails, read the directions!

Hell. What does an AP know anyhow?

Edited January 5, 2016 by Mcstealth

[carusoam]

Nice follow-up, Snowds.

Thanks for sharing your details.

Best regards,

-a-

[jetdriven]

1 hour ago, snowds said:

Finally got the overhauled Rocket running perfectly smooth at low power settings (16 inches and below, on final).  It is critical that the fuel flow set up be done exactly according to the Rocket STC document (and not the Continental service bulletin); the fuel system builder swore there was no way the engine would run properly being set so lean at the low-end.  Against his intuition, the A&P took two full turns on the low end fuel flow screw, and it fixed the roughness.  Ridiculously smooth now.  He had never set an engine so lean that there is no RPM increase when leaning on the ground at 1,000 rpm, but that's what the STC called for, and that's what ended up working.  When all else fails, read the directions!

I set my IO-360 with basically no RPM rise when the mixture is pulled to cutoff, as allowed in Precision SIL RS-67.  How many "run it up and burn off fouled plugs" occurences in 600 hours?  TWO.  Both involved extended ground holds for takeoff.