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Pre-starting..

ccsmith51

ccsmith51

Well Known Member
I have been away from home for 3.5 months. I will get back to the hangar in about two weeks.

My O-360 RV-4 has been in the hangar while I have been gone and not run.

Is there anything special I should do before starting the engine? Pull the top plugs and squirt something in? Pull the prop through a number of times to get some oil flowing? Suggestions?

Thanks,
 
Chris:

A few suggestions:

1. If it's been 3.5+ months since the last oil change, I would change the oil first.

2. After adding new oil, remove the bottom plugs and crank the starter for up to a minute. This will pressurize your engine and get oil into the galleys

3. Install and torque the plugs, start, go have fun.


Mike
 
Mike,

Thanks for the suggestions. It has been 35 hours since my last oil change, so that is good timing.

But, shouldn't the oil be changed when it is hot? Or in a case like this does it not matter?

Thanks,
 
You really should consider some preventitive measures if the engine is going to sit for that long in a humid climate. It is a perfect setup for camshaft and cylinder rust.

http://www.sacskyranch.com/corrosion.htm

John Clark ATP, CFI
FAAST Team Representative
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA
 
John Clark said:
You really should consider some preventitive measures if the engine is going to sit for that long in a humid climate. It is a perfect setup for camshaft and cylinder rust.

http://www.sacskyranch.com/corrosion.htm

John Clark ATP, CFI
FAAST Team Representative
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA
Click to expand...

Thanks, John, I appreciate the comment and link. I had not expected that amount of time between operations, otherwise I would have done some preparation. The question now is, what is the best procedure to minimize any damage when starting after sitting for so long...
 
Thoughts

drill_and_buck said:
"...remove the bottom plugs and crank the starter for up to a minute....
Click to expand...

Be sure to disconnect & ground all of the spark plug leads.

With the plugs out, you should be able to spin the prop pretty well by hand - probably enough to get some basic pressure built up - but probably not enough to get a good splash lube (wouldn't happen with the starter either). If you do use the starter, turn it by hand for a couple of revolutions first.

The 35 hours / 3.5 months doesn't seem too bad on the oil. I might be tempted to start and run on the existing oil for an hour or so, then change it.

YMMV - good luck.

Dan
 
Oil change

Changing oil is a good idea, however I would wait until after you have "knocked all the rust off" before you change it. One good flight. +1 preoiling with the starter. Starter duty cycles generally 30 sec. on, two min off, 30 sec. on, 30 MIN off.
Also might consider calling Lycoming with your engine serial number in hand, they just might send you a copy of "Key Reprints" at no charge. Lotsa good info.
 
Thanks everyone for the suggestions

So, to summarize what has been suggested:

1) Remove cowling
2) Remove and ground all spark plug wires
3) Remove lower plugs
4) Starter spin for 30 seconds
5) Let sit for 2 minutes
6) Starter spin for 30 seconds
7) Let sit for 30 minutes
8) Install plugs, wires, cowling and fly for an hour
9) Change oil

Sound right? Thanks,
 
I'm not sure why you would need to ground the plug wire, just leave he mags off. ( grounded.) Other than that, that is what I would do. Good luck and happy flying!
 
Last edited:
Geico266 said:
I'm not sure why you would need to ground the plug wire, just leave he mags off. ( grounded.) Other than that, that is what I would do. Good luck and happy flying!
Click to expand...
If he has a key switch, he will have to ground the plugs. If he used mag switches and a starter button, then he can just leave the mags off.
 
N941WR said:
If he has a key switch, he will have to ground the plugs. If he used mag switches and a starter button, then he can just leave the mags off.
Click to expand...

I do have a key switch. What is the easiest and safest way to ground the bottom plugs that I remove?

Or, could I leave the key off and jump the starter and not worry about grounding (assuming I don't have a hot mag, which last time I checked I didn't...)
 
Another item (ref post above)

Charge the battery....

This schould ofcourse be done beetween pt 3 and 4.
 
Last edited:
ao.frog said:
Charge the battery....

This schould ofcourse be done beetween pt 3 and 4.
Click to expand...

Thanks for the suggestion. The battery (Odyssey) has been on a trickle charger the whole time I have been gone, so I expect (hope) that it will be charged and in good shape when I get back..
 
There is more you can do

I agree with the above comments completely, but there is more you can do. The first minute of start up is where parts are dry from sitting and most of the wear occurs. I agree that spinning the engine to get the oil moving is a wonderful idea, but.
You can completely fill your crankcase with oil, then with sparkplugs out, rotate the prop for many turns. This has the cam and cylinder walls completed covered in oil while the parts are rubbing together. Then drain the oil. Refill with proper amount and go fly. I have never seen this printed anywhere but I have done it and felt good about it. YMMV.
 
Dry start up advice

Searching for advice on starting after a prolonged period of inactivity and came across this. Has anyone tried filling the crankcase completely with oil as mentioned below ?


Bob Martin said:
I agree with the above comments completely, but there is more you can do. The first minute of start up is where parts are dry from sitting and most of the wear occurs. I agree that spinning the engine to get the oil moving is a wonderful idea, but.
You can completely fill your crankcase with oil, then with sparkplugs out, rotate the prop for many turns. This has the cam and cylinder walls completed covered in oil while the parts are rubbing together. Then drain the oil. Refill with proper amount and go fly. I have never seen this printed anywhere but I have done it and felt good about it. YMMV.
Click to expand...
 
My Pitts(IO-360) sits for 5 to 6 months in the winter. When it gets warm enough to fly March-April I start it up and fly it home. I don't think these engines are that fragile that you can't just start it and fly.

EDDY
 
Considering the cam takes the biggest beating at startup and is also completely dependant on "splash" lubrication, you want 1000+ RPM ASAP. Grinding on the starter may float the bearings, but your cam is dying with every dry turn.
 
Yes I know it's splash lubricated but I was wondering about the idea of filling the case with oil to lubricate the cam before attempting a start ?
 
edsong said:
My Pitts(IO-360) sits for 5 to 6 months in the winter. When it gets warm enough to fly March-April I start it up and fly it home. I don't think these engines are that fragile that you can't just start it and fly.

EDDY
Click to expand...

I'm with you on this. If these engines were as fragile as everyone thinks they are, they would never work for the average Cessna or Piper owner.. Just be smart about it, and start the **** thing, in my opinion. I think oil on the cam is the one thing to think about, and all the cranking in the world won't help that. I assume an advantage of roller lifters, like I have, is less wear when 'dry'.
 
Dr107flyer said:
Yes I know it's splash lubricated but I was wondering about the idea of filling the case with oil to lubricate the cam before attempting a start ?
Click to expand...

The cam is about the highest thing in the engine. You would have all the cylinders full of oil (under the pistons) before you got to the cam. You'd have probably 5 gallons of oil in there.

Just go for the start, and make sure it lights right off.
 
Toobuilder said:
The cam is about the highest thing in the engine. You would have all the cylinders full of oil (under the pistons) before you got to the cam. You'd have probably 5 gallons of oil in there.

Just go for the start, and make sure it lights right off.
Click to expand...

Yes I think I will but I keep coming back to lycoming SI1241C where it states after prolonged inactivity to crank it with plugs out. So doesn't that also make the cam situation worse ?

http://www.lycoming.com/Portals/0/t.../Pre-Oiling Engine Prior to Initial Start.pdf
 
Agreed...........but.........

I'm of the same mind David.....but if we do the math, a minute of cranking is only about 100 turns. That's the same as the first 6 seconds of running at 1000 rpm, if you had just fired up the engine instead.
.......seems like it's worth turning by hand a few times, or cranking (plugs out just saves the starter, right?) to get oil to the bearings.
NOTHING we do will lube the cam & lifters until the oil is warm & splashing around, from what I understand.

(but I could be completely wrong.)
 
I do what others have suggested. I pull top or bottom plugs, whichever is easiest, spin by hand a couple of dozen times, then crank the starter until I get oil pressure. One of the reasons for this is to lubricate the engine before going high rpm (engine idle is high rpm without oil). The second reason is just in case I don't get oil pressure. I have had 2 engines that lost their prime somehow, or wouldn't prime. I know it shouldn't happen because of the desk of the oil pump, but it does happen. The solution here is to pull he accessory case, remove the oil pump, pack with Vaseline and reassemble. This will prime it and the vaseline will dissolve in the oil. It could be that high rpm would prime the oil pump, but I'm not willing to risk that not happening. It's also good to listen for any rust scraping when you start pulling it through by hand. That would help to verify if internals are rusting.

I would also run and fly it before changing the oil so the hot oil will suspend the contaminants and they will drain with the oil.
 
Science experiment.

Toobuilder said:
The cam is about the highest thing in the engine

Just go for the start, and make sure it lights right off.
Click to expand...

I agree. Do some science for us and report back! Pull a galley plug, perhaps the oil pressure sendor line, pull the plugs, then turn the prop by hand. I think you will be surprised at how quick oil flows. If the system has not been opened, I'll bet a hot dog at the next airshow you get oil in less than a full turn. The oil takes years to drain out of the close fit of the crankshaft bearings and even the galleys.
So my point is what you will be doing is oiling an already oiled crankshaft and spinning an already dry camshaft.
One thing you can do is blast some oil up into the cylinders (piston down) with an air gun and a straw full of oil, maybe a half teaspoon. Roll it over once to push any excess oil out. Then start it.
I wish there was a way to pre oil the cam short of flipping the engine upside down or disassembly.
I have the Nye Nozzles installed on my engine, but I don't believe they would oil the cam unless they have normal pressure on them, like from running the engine.
Tim
 
Additional data points here...

1) I recently installed a mid-time O-320 on a friend's airplane. Don't know when it last ran, but from the time he purchased it at least 6 months had passed with no oil in the engine whatsoever (oil removed for shipping). I added oil, removed all 8 plugs and spun the engine by hand-propping as fast as I could with a well padded hand/forearm. Oil pressure came up in about 30 seconds of hand-spinning and achieved nearly 40psi pressure.

2) My project aircraft has an O-360 installed, pickled for long-term storage. Intake runners and exhaust are removed and the ports covered in sealing plates. Engine is FULL of oil. Cylinders, both above and below the pistons, are FULL of oil. You don't want to know how much oil this takes. More than 5 gallons. Very $$$ but not as expensive as rust. Still, you can't get oil into the top of the cylinders or the top of the crankcase, so I was worried. I dropped the oil from the 2 cylinders with pistons closest to BDC and inspected with a borescope. It was so bright in there that I had to turn the borescope light intensity down to minimum to avoid blinding myself. I conclude that one major advantage of filling the engine with oil is excluding air volume subject to condensation and filling leakage paths, preventing fresh, moist air from entering the crankcase.

Now I sit with fingers crossed in hopes this theory works for the cam... :)
 
If there is rust on the cam shaft then I would think the damage is done no matter how much oil reaches it before start. I have always hand propped the engine a few times and started it but I also don't let it sit for three months.
 
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