Overhaul issues

[ArtVandelay]

Just finished overhauling my IO-360 and have a couple of squawks:
My JPI complains about the fuel pressure being too high (30 psi). But the POH gives the range to be 14-30, so the JPI should not complain until it reaches 31. My guess is internally it’s 30.x. It seems to be breaking in, it used to reach 31. It’s only a problem during initial power ups, cruise is drops down to ~26. Can I expect this problem to go away with further break in?
 
Second problem is the throttle cable doesn’t have enough range, so pulling power never results in the gear horn. Is there a way to get some additional travel? I assume the arm that cable is connected to is standard, there aren’t longer arms.
 
TIA,
 
 
Tom

[Oldguy]

Tom, 

My J starts honking the gear horn at 12" MP if I have not dropped it yet. If yours gets down to that range and no horn, the adjustment will be in the switch riding on the cable under the panel. This would be something your mechanic should be able to address rather quickly (depending on hand size). Does your engine go to idle when you pull the throttle out? I would think if it did not drop down to idle, you would have a dickens of a time landing with partial power still being developed by the engine.

Good luck.

[Oldguy]

On 4/28/2016 at 12:09 PM, cctsurf said:

Here's a pic, notice that there is a thicker area of the cable which pushes the microswitch when the throttle is in, and when pulled back, it can drop in next to the flex cable (as pictured above).

[ArtVandelay]

56 minutes ago, Oldguy said:

Tom, 

My J starts honking the gear horn at 12" MP if I have not dropped it yet. If yours gets down to that range and no horn, the adjustment will be in the switch riding on the cable under the panel. This would be something your mechanic should be able to address rather quickly (depending on hand size). Does your engine go to idle when you pull the throttle out? I would think if it did not drop down to idle, you would have a dickens of a time landing with partial power still being developed by the engine.

Good luck.

Yes, it goes to idle when pulled out. I already adjusted the microswitch and have it as far forward as it will go. Even if pulled all the way out, doesn’t pull out enough to get the cutout portion.

i don’t know if the metal sleave is also adjustable, I just move the switch.

[MIm20c]

JPI sets the redline on the top of the range. In your case 29.9 would be fine but 30.0 is an emergency, engine falling apart range.  

[Shadrach]

7 minutes ago, ArtVandelay said:

Yes, it goes to idle when pulled out. I already adjusted the microswitch and have it as far forward as it will go. Even if pulled all the way out, doesn’t pull out enough to get the cutout portion.

i don’t know if the metal sleave is also adjustable, I just move the switch.

Have you verified full travel of the butterfly at the throttle body?  Did you have your engine overhauled or buy a "Factory" overhaul?

[carusoam]

JPI 900s are known to be very accurate...

if the limit is 30...

And your analog mind thinks 31 is the next possible alarming step... 

Expect that the Christmas tree is going to light (annoyingly) on every take-off roll... at 30.1 or 30.01....

But, this is mostly an engine rpm control challenge... where rpm redline is much more difficult to control in transit...

 

To look into fuel pressure too high... that is a completely different challenge that can be looked up around here.  Something has changed with the pump design/ construction... several MSers ran into this challenge with various resources of OH... use the search or start here...

 

How is that for age related memory challenges...?

Best regards,

-a-

[Shadrach]

Overpressure is a known issue with some new mechanical pumps. contact the overhauler.

[ArtVandelay]

Have you verified full travel of the butterfly at the throttle body?  Did you have your engine overhauled or buy a "Factory" overhaul?

Overhauled, and I believe I have full power and idle, so that tells me I have full travel. My engine was overhauled.


Tom

[67 m20F chump]

I would think you could check the micro switch on the throttle with an ohm meter.  It sounds like it may be sticking.

[SheryLoewen]

Think you want shorter--move the control up a hole on the arm.

Paul---LMS

[FloridaMan]

20 hours ago, ArtVandelay said:

Just finished overhauling my IO-360 and have a couple of squawks:
My JPI complains about the fuel pressure being too high (30 psi). But the POH gives the range to be 14-30, so the JPI should not complain until it reaches 31. My guess is internally it’s 30.x. It seems to be breaking in, it used to reach 31. It’s only a problem during initial power ups, cruise is drops down to ~26. Can I expect this problem to go away with further break in?
 
Second problem is the throttle cable doesn’t have enough range, so pulling power never results in the gear horn. Is there a way to get some additional travel? I assume the arm that cable is connected to is standard, there aren’t longer arms.
 
TIA,
 
 
Tom

I've got some bad news for you. After over 100 hours on my engine, I still get the same behavior from my EDM-900. When I had the engine monitor installed in the Rocket, I had it installed in front of me so I wouldn't have to deal with the red LED if there were something that would touch a limit for an instant. I believe the "red light" issue creates a real hazard. You must either verify and clear the indication during critical phases of flight, or becoming complacent with a blinking red light that frequently cries wolf. With the engine monitor installed close enough to not need the asshole light, it's much more tolerable. Indications just turn red and are not intrusive like a blinking red light that says "ENGINE", you can glance down and be aware of them and go on about your business. Added bonus is your passengers don't get nearly as alarmed either. 

 

[ArtVandelay]

I would think you could check the micro switch on the throttle with an ohm meter.  It sounds like it may be sticking.

No, I eyeballed it, it’s a cable adjustment problem.

 

 

Tom

[ArtVandelay]

Think you want shorter--move the control up a hole on the arm.
Paul---LMS

But there isn’t multiple holes, IIRC, so adjustment I think I can make is how the cable is clamped? When I go in for my 10 hour oil change I plan on shutting down the engine with the throttle cable set in the proper position. Then I will have the AP disconnect the cable, I’ll pull the throttle until switch activates, and tell him to reconnect it. My guess is that full throttle will no longer go completely to the firewall. Other option is to disassemble the cable and add spacers (washers) to at least have the throttle knob butt up against something at full throttle.



Tom

[Guest]

It sounds like you may need to reposition the throttle arm at the servo.  It has serrations to allow for this.

Clarence