Low Compression, Worn Exhaust Valve Guide, Decisions, Decisions

[C-FIJK]

Hello Steve I was in the same position 2 years ago pulled the cylinders to go to 160 hp and then found a cam about to go , 1400 snew wide deck engine , I chose a complete overhaul only bad decision I made was went with overhauled cylinders , ended up 50 hrs later getting all new factory lycoming cylinders under warranty , my advice buy all new not much more .

So I have concidered lots of options. I thought of pulling #4 and replacing the guide. I figure if I do one I should do all four. If I am going to have all four cylinders off I want to put those 160 hp pistons in, new rings, hone. Why not go ahead and install new exhaust valves, might as well overhaul them. Not much difference in price between new and overhauled. I have installed several LyCon engines with port and polished cylinders and know how smooth they run and appear to make more power as well. Can you see the snow ball getting larger? It could go on with a complete engine overhaul with balance and reindexing of the crank and why not DLC coat parts and crio them as well and o'ring the crankcase. Not in the budget, my banker retired and I don't want to meet the new, young loan agents nor pay them interest so I am not going there. Hopefully in 1000 hours I don't have a kid in college and another in high school eating me out of house and home and I know the house and hanger will be paid for. I think a set of new Lycoming cylinders from LyCon with their port and polish is the route I am going to take. I could keep flying it cheaper but I don't get paid to work on my own airplane and when I am not working on other's airplanes I would rather be flying mine. Besides, I want what I want so what the hell.

 

[skywagon8a]

...I chose a complete overhaul only bad decision I made was went with overhauled cylinders , ended up 50 hrs later getting all new factory lycoming cylinders under warranty.

This raises questions. WHY did those cylinders only go 50 hours? There is no excuse for this. What in particular went bad?

 

[C-FIJK]

Had great compressions but a lot of oil above the piston, shop was excellent and covered all under warranty

 

[skywagon8a]

Had great compressions but a lot of oil above the piston, shop was excellent and covered all under warranty

No further comment.

 

[tempdoug]

Had great compressions but a lot of oil above the piston, shop was excellent and covered all under warranty

they forget to put the valve seals on?

 

[Steve Pierce]

So got my new rocker shafts, buttons, intakes hoses, drain back lines and decided I need some new engine mount bushings as well. Had had these ordered for some time but Lycoming had the back ordered till the first week in Sept. When they didn't ship I checked and they are now BO till Oct so I ordered Superior. They seem a bit harder when tightening to the 1.84". I think they were due. Had to open up the hole in my lower cowl where my Sutton exhaust pipe comes out.


Got everything finished Saturday morning and did a quick run and leak check after installing a Sensenich 56" pitched prop. It rapped up to 2600 plus rpm on the shallow take off at 14.5 to 15 gph fuel flow. When I leveled off I noticed a lot more vibration than with my Borer, so much so I took the 56" Sensenich that came on my Cub off my brother's Clipper and tried it. Still has a bit of vibration. Burns almost a gallon to a gallon and a half more fuel per hour but goes 5-8 mph faster. Put 3 hours on it so far and can't wait to put the Borer back on, hopefully by next weekend. Seems to have used about 1/2 a quart of oil in the 3 hours and is running about 190 to 200 degree oil temp at 90-95 OAT. This gauge/engine has always been run cool. It seems to pull hard so I think it will be a big plus once the Borer is back on.

Haven't pulled the trigger on an engine monitor yet. The SR-8A a friend brought me will need 4 new CHT and EGT probes to the tune of $600. Thinking of maybe the JPI EDM350 Basic for about $800 retail. It is for experimental only but CHT and EGT are not required on a Super Cub. I could install my EI fuel flow transducer and not take up extra panel space except the instrument size. Gotta look into the legalities of that.

Anyway, it is good to have my airplane back in the air and will be even better when I can use the Borer and really see what the changes in 10 hp plus the flow matching really did.

 

[C-FIJK]

Steve that's what I noticed as well bit more fuel but pulls harder. The down side I had to break engine in with borer prop 82+43. So heavy loads and higher rpm took me longer but is tight now

 

[BC12D-4-85]

Maybe a dynamic propeller analysis and balance is in order? It can reduce vibration providing the propeller itself is balanced properly and both blades pitched equally.

Gary

 

[DENNY]

My 700 hour bushings looked the same as yours, engine angle changed 3-4 degrees with the new ones. I gained 3-4 mph at 2400 rpm. Might be something worth changing at 1000 hours
DENNY

 

[mike mcs repair]

My 700 hour bushings looked the same as yours, engine angle changed 3-4 degrees with the new ones. I gained 3-4 mph at 2400 rpm. Might be something worth changing at 1000 hours
DENNY

the bushing are on my inspection sheet as an item, you will wear the bottom ones out first & quite quickly...

 

[hotrod180]

…..Thinking of maybe the JPI EDM350 Basic for about $800 retail. It is for experimental only but CHT and EGT are not required on a Super Cub. I could install my EI fuel flow transducer and not take up extra panel space except the instrument size. Gotta look into the legalities of that......

On a similar vein, I'm thinking about adding a non-STC'd / non-TSO'd (aka "experimental only") 6 point CHT / EGT to my C180.
This would be in addition to the required single-point CHT, so is it legal?
I not only need to convince myself, but the IA(s) I do my annuals with.

 

[astjp2]

My first answer (post #3) was a minimal approach to fly a couple hundred more hours . But......if I were removing all 4 cylinders I would also install new rod bearing at the same time because it's not that much more work or money?

Glenn

Doesnt the current lycoming service manual require you to replace the rod bolts and nuts if you pull the rods? Which would be required of a certified mechanic to sign off the logs that the did IAW lycoming procedure?

 

[CamTom12]

Due to a recent turn of events (two engine gauges crapping out on the same trip) I’ve got an EDM 350 heading my way. I ordered it with their oil temp probe and ordered a standard VDO pressure transducer from amazon at $200 less than JPI wanted. If it doesn’t work then I’m only out $60. I intend to add fuel flow down the road as my budget recovers.

Steve, I’ll keep you updated on my thoughts on the system if you’re still interested.

 

[Doc65]

lol!!!

:roll:

Do you think the nitrous contributed to the failure?

 

[Steve Pierce]

Doesnt the current lycoming service manual require you to replace the rod bolts and nuts if you pull the rods? Which would be required of a certified mechanic to sign off the logs that the did IAW lycoming procedure?

I am not sure if it is required without looking it up but it is common practice.

 

[akavidflyer]

If I was experimental I would look at the EDM350 from JPI. I am not a JPI fan due to my experience with customer service but that is a quite capable instrument for the money. Installed one in a Carbon Cub SS.

I called Electronics International but they are not planning on another rebate until Sun &Fun. Sales is checking with management to see if they would give me the rebate that just ended the end of August but no return phone so far.

I was talking to my IA yesterday about this monitor. If I leave my required steam gauges in and install this he has no issues with just doing a log book entry. His take is TSO means nothing really if your flying part 91.

 

[CamTom12]

I was talking to my IA yesterday about this monitor. If I leave my required steam gauges in and install this he has no issues with just doing a log book entry. His take is TSO means nothing really if your flying part 91.

Mine's installed and would be functioning 100% if I had a magneto. I run dual Pmags and have been having (self-induced!) issues connecting to adjust the Pulse Per Revolutions sent via the Tach Output on the ignition. Other than reading double RPM, the EDM 350 is working perfectly, and when my new RS-232 to USB adapter comes in the mail I'll be able to fix that problem. I've learned more about serial data transmission protocols in the last 5 days than I ever hoped to know :lol:

I installed all the new CHT and EGT probes they sent, but I re-used my EI OAT probe. I just cut the K-type connector off and crimped some female D-sub terminals on and it works great. I also re-used my shunt for the Ammeter. I think the gauge is calibrated for a 100A shunt and mine's a 60A shunt. I think it's reading a little on the high side on either charge or discharge, but the center around 0A is still right on so I'm not worried about it.

I also bought a $70 VDO oil pressure transducer off Amazon that accidentally also has a 0psi warning switch, so I'm going to wire that into a light on the dash. I thought about keeping my mechanical oil pressure gauge and "T"-ing the line, but with both the EDM 350 psi reading plus a light on the dash I think that's duplicate enough. The warning switch apparently uses a different circuit than the pressure-reading side of the transducer, and uses its own 12V input. In your case a simple "T" fitting should work great to keep your certified gauge.

I don't have MAP or fuel flow transducers yet. I think I'm going to try an automotive MAP sensor, but I'll get the aircraft-certified fuel flow cube. Not messing around with a fuel line to the engine.

 

[skywagon8a]

I also bought a $70 VDO oil pressure transducer off Amazon that accidentally also has a 0psi warning switch, so I'm going to wire that into a light on the dash. I thought about keeping my mechanical oil pressure gauge and "T"-ing the line, but with both the EDM 350 psi reading plus a light on the dash I think that's duplicate enough. The warning switch apparently uses a different circuit than the pressure-reading side of the transducer, and uses its own 12V input.

I would keep the direct reading oil pressure gauge. That is the one most important instrument in the airplane. An electrical failure would render both of your other two options out of service.

 

[akavidflyer]

I would keep the direct reading oil pressure gauge. That is the one most important instrument in the airplane. An electrical failure would render both of your other two options out of service.

That my plan as well. I only have OT and OP in my panel and they will stay. Getting the 4 cyl CHT and EGT is my biggest want at this point. Any other functions are just a bonus. The basic package for under 800 bucks seems like a no brainer.