jav8or
Update on Bad Vibration …abwaldal
OK here is an update to my prop vibration that wasn't a prop vibration at all.
Went to a local shop and talked to an aviation guru of 55 years. Explained all the thoughts and efforts.
He was convinced it was a bad front main bearing and suggested I DO NOT fly the airplane and pull the motor and split the case. He had seen it before, and even on a brand new Lycoming engine.
OK serious job ahead.
I pulled the motor tore down and OOPS!!!!!! no bad bearings, But I did find broken rings on #4 so good to pull the motor.
But because I had another 0-360 in my hangar, I installed it before I tore down the old motor.
Upon flying with new motor there came a holy #$^*&%* moment as the vibration was still there. WHAT on earth is going on here?????
I had inspected the airframe early on in this vibration problem to assure nothing was loose, falling off etc.
took off the wheel pants and went flying. Guess what YES the vibration was gone.
The problem was a couple slightly loose rivets on the left wheel pant.
The baffling thing about the vibration is it started at one point and never changed over 6-8 hours of trying to figure it out.
OH well now I have my freshly overhauled motor in the bird and the oil stays looking quite clean even after 25 hours. It used to get very dark after 4-6 hours.
I'm not totally unhappy to have pulled the engine because I found the very broken top ring on #4 ( Broken into 16 pieces)
NO more vibrations, And I did reinstall the Balance wheel.
life goes on and the plane is reusable. It may not have been if the ring migrated out of the where it is supposed to be.
My luck varies FIXIT
rockitdoc RV-14A Update
It's been awhile since my last post, so here I go to catch up. Lots has happened since last year. Mostly, I moved the whole assembly operation from my home shop to my hangar at KFNL. This happened in September '24. Here's how we moved her.
db1yg
Need some help on where to start trouble shooting a fuel flow issue.
My fuel flow (red cube) was showing some unusual flow rates in my morning flight today. This is an IO340 Continental Titan engine (8:1 compression) with the fuel pressure pick up at the mechanical pump outlet and the fuel flow transducer just prior to the flow divider connected via a 90 degree fitting using the Aircraft Specialty mount. This set up has provided 130 trouble free hours to date.
I had leaned to my normal 25 to 40 degrees lop and after a few minutes the flow indication went from 7.2 gph (which is normal) to 5 gph and then fluctuated +-1-2 gph. Normally I see a steady reading with maybe a 0.2 gph fluctuation. Fuel pressure was steady as was egt and engine performance. The OAT was unusually hot at my cruising altitude at 75 degrees and the cht’s in climb had to be managed (#4 hit 390 prior to level off) so there was considerable heat in the cowl. Additionally I am running a 50% blend of 100LL with alcohol free 87 octane pump gas.
My thoughts on what could be the cause:
1. Fuel flow transducer is failing or I have a ground issue?
2. The unusually hot temperatures along with the 50% pump gas was releasing vapor at the 90 degree outlet from the fuel flow transducer.
Since I have never had this issue prior and the temperatures were unusually high today I lean toward cause #2. The problem with this conclusion is that the fuel pressure was not fluctuating, egt’s were steady, and performance was not affected.
My current plan is to fill with 100 LL and see if the issue goes away.
Comments—thoughts?
TimSPEED
DonF -14
RE: Aileron bellcrank play …RV7A_Flyer
As noted in several other posts, this is normal...see DWG-15A
The key point here is that the bolt/nut and the bellcrank bracket *must capture the bronze bushing*. The bushing must not rotate, and the bellcrank rotates *around* the bushing. Note that the drawing calls for the bushing to be slightly longer than the steel tube of the bellcrank.
You said you noticed this axial play on one wing...there should be at least a smidge of play on both bellcranks. Go check the other wing.
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Master Cylinder Fitting
Good Day All! I’m looking to repack a leaking Cleveland Master cylinder, since the unit is leaking from what appears to be the plastic fitting. I’m thinking of just replacing the fitting while I have it out, but I cannot find a part number anywhere. Is the piece in the picture just sourced...
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Update on Bad Vibration …abwaldal
OK here is an update to my prop vibration that wasn't a prop vibration at all.
Went to a local shop and talked to an aviation guru of 55 years. Explained all the thoughts and efforts.
He was convinced it was a bad front main bearing and suggested I DO NOT fly the airplane and pull the motor and split the case. He had seen it before, and even on a brand new Lycoming engine.
OK serious job ahead.
I pulled the motor tore down and OOPS!!!!!! no bad bearings, But I did find broken rings on #4 so good to pull the motor.
But because I had another 0-360 in my hangar, I installed it before I tore down the old motor.
Upon flying with new motor there came a holy #$^*&%* moment as the vibration was still there. WHAT on earth is going on here?????
I had inspected the airframe early on in this vibration problem to assure nothing was loose, falling off etc.
took off the wheel pants and went flying. Guess what YES the vibration was gone.
The problem was a couple slightly loose rivets on the left wheel pant.
The baffling thing about the vibration is it started at one point and never changed over 6-8 hours of trying to figure it out.
OH well now I have my freshly overhauled motor in the bird and the oil stays looking quite clean even after 25 hours. It used to get very dark after 4-6 hours.
I'm not totally unhappy to have pulled the engine because I found the very broken top ring on #4 ( Broken into 16 pieces)
NO more vibrations, And I did reinstall the Balance wheel.
life goes on and the plane is reusable. It may not have been if the ring migrated out of the where it is supposed to be.
My luck varies FIXIT
Bad vibrations ???
I have an RV-6A 0-360 c/s prop 650 hours Channel chrome cylinders burns 1 quart in 6 hours. SDS EM5F fuel and ignition systems run LOP. Dynon Hdx panel. I've owned it for 4 years flown 200 hours in that time. Always thought about balancing the prop. Have normal vibrations, Compressions just...
vansairforce.net
rockitdoc RV-14A Update
It's been awhile since my last post, so here I go to catch up. Lots has happened since last year. Mostly, I moved the whole assembly operation from my home shop to my hangar at KFNL. This happened in September '24. Here's how we moved her.
Scott's RV14A: N52XL
MIlestone! Installed the canopy. I takes three people. One inside to guide the canopy release pin into the canopy hinges and two people on either side to guide the canopy into the hinges while holding it upright. So, now it's on to finishing the wings!
vansairforce.net
db1yg
Need some help on where to start trouble shooting a fuel flow issue.
My fuel flow (red cube) was showing some unusual flow rates in my morning flight today. This is an IO340 Continental Titan engine (8:1 compression) with the fuel pressure pick up at the mechanical pump outlet and the fuel flow transducer just prior to the flow divider connected via a 90 degree fitting using the Aircraft Specialty mount. This set up has provided 130 trouble free hours to date.
I had leaned to my normal 25 to 40 degrees lop and after a few minutes the flow indication went from 7.2 gph (which is normal) to 5 gph and then fluctuated +-1-2 gph. Normally I see a steady reading with maybe a 0.2 gph fluctuation. Fuel pressure was steady as was egt and engine performance. The OAT was unusually hot at my cruising altitude at 75 degrees and the cht’s in climb had to be managed (#4 hit 390 prior to level off) so there was considerable heat in the cowl. Additionally I am running a 50% blend of 100LL with alcohol free 87 octane pump gas.
My thoughts on what could be the cause:
1. Fuel flow transducer is failing or I have a ground issue?
2. The unusually hot temperatures along with the 50% pump gas was releasing vapor at the 90 degree outlet from the fuel flow transducer.
Since I have never had this issue prior and the temperatures were unusually high today I lean toward cause #2. The problem with this conclusion is that the fuel pressure was not fluctuating, egt’s were steady, and performance was not affected.
My current plan is to fill with 100 LL and see if the issue goes away.
Comments—thoughts?
Fuel Flow Fluctuation
Fuel Flow fluctuations Need some help on where to start trouble shooting a fuel flow issue. My fuel flow (red cube) was showing some unusual flow rates in my morning flight today. This is an IO340 Continental Titan engine (8:1 compression) with the fuel pressure pick up at the mechanical pump...
vansairforce.net
TimSPEED
I made my own tiedown rings.
Hi everyone. Thought I would share a little side quest I did whilst I am building my RV-8A. When building the wings (I am nearly finished here) I really did not like the way the mount for the tie down rings sat around a quarter inch above the wing lower skin. It means you cannot screw in a tie...
vansairforce.net
DonF -14
RV 14 Elevator close out tab
9-04 Step one calls for the top skin to be bent 1/64" from the bend line. Then step two calls for the lower skin to be bent 1/32" from the bend line. This seems backwards as when assembled the top skin goes over the top of the bottom skin tab.
vansairforce.net
RE: Aileron bellcrank play …RV7A_Flyer
As noted in several other posts, this is normal...see DWG-15A
The key point here is that the bolt/nut and the bellcrank bracket *must capture the bronze bushing*. The bushing must not rotate, and the bellcrank rotates *around* the bushing. Note that the drawing calls for the bushing to be slightly longer than the steel tube of the bellcrank.
You said you noticed this axial play on one wing...there should be at least a smidge of play on both bellcranks. Go check the other wing.
Aileron bellcrank play
Was doing a condition inspection yesterday on my Dad's RV-8 and noticed something peculiar on the right hand aileron bellcrank out in the wing. I didn't build the plane, but it appears the bellcrank rotates around a bushing held in between 2 brackets with a 1/4" bolt. There's no play axially...
vansairforce.net
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Get your VansAirForce.net Charity Cap!
VAF Charity Cap: Help your charity and promote this site.
Get the cap all the cool kids are wearing! I don’t get a penny. It’s around $15. $5 more if you want your N-number on the back (I put 'STAFF' on the back of mine because it makes me laugh. Put STAFF on yours too if it makes you smile). And down the road $10 to the charity of your choice...
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Please consider donating yearly to help keep this American 1-person pirate ship afloat:
Older issues of the ‘VAF News’ can be found at:
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THE VAF LIST (a list of RV-related lists)
THE VAF LIST (a list of RV-related lists)
The VAF List ...a list of RV-related lists. RV-related things you might want to browse over (a closed post that is sticky and maintained by dr). Link to this in 'Links' in the menu. v/r,dr Small businesses that help bring you this list of RV-related lists: 360 Avionics www.360Avionics.com Ace...
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