MYHELL99

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Hello all,
The thread hasn't been active in a while, but hopefully someone could be able to help me out?

I was able to acquire a new 777 last year and began breaking it in last year. I had about a 1/2 hour on it last Fall, and it sat until now. I did add about 10-15 ml air tool oil (Sears Craftsman) after every day's run. Fuel is Cool power 10%, reduced 50/50 with Methanol from Red Max fuels.

So, last week I began to continue the break in procedure. I propped the engine and didn't notice any hydraulic lock, so I just started it up. I didn't drain the engine. She ran fine, but the exhaust was definitely darker than the first 1/2 hour or running. I attributed this to the after run oil being spat out. After 20 minutes, it did not get better so I investigated and opened it up.

The inside had a bunch of FOD particles that looked like coagulated fat. Very odd. The bearings had some corrosion on them as well. I took apart each cylinder and cleaned every part with Q-tips and WD-40. All 7 cylinders had this crud, with the two lower ones having just a bit more. Everything cleaned up easy and well. I didn't want to mess with the front end disassembly, so I just got Q-tips through the cam gear holes and sprayed and cleaned as best I could. I've been modelling for 35 years and have never seen these types of deposits in the combustion chamber. It totally came off with the slightest wipe. Odd.

I put it back together and ran it again (only WD-40 in the engine initially). Well, same nastiness out the exhaust!
Reading through the thread, I upped the oil content to 10% by adding pure castor to my mix. Same exhaust residue (last photo). Also, the exhaust oil is a lot, like a normal 2-stroke glow. I feel like it's the air tool oil being petrol based, and doesn't mix well with the glow fuel?

I have the OEM carb with high speed set at 5.5 turns, and low speed set at 4.5 turns. It does run nice and rich, but not choking rich. I could make it choking rich if I wanted, so draw isn't a problem.

I'm using a Master Airscrew wood 24x10 and getting 1200 RPM idle with glow on (and can get it to idle this low without glow, if I lean out the low needle a bit), and 4800 RPM max. Cylinders are reading around 150-160 degrees F while at max RPM, but normally reading around 125-130 degrees at 1/2 throttle.

Questions:
1- Is the amount of exhaust oil "normal"? It's pretty messy, as much as a 2 stroke glow.
2- What do you think those particulates floating in the exhaust oil are? I mean, it keeps coming, even after running for ~20 minutes!
3- I just bought Klotz Super Techniplate oil to use as after run oil because it will mix better with methanol during next session's run. Thoughts on this?
4- My prop is a bit crunchy after the engine sat around for months. I cannot make it go away. Do I need to replace the main bearing right away, or see how things go?
5- Separate subject: Thoughts on using a Lipo with voltage reduced by Castle BEC Pro down to 6.0v to power McDaniels glow system? -OR- 6.6v Life direct into McDaniels system? It's hard to find nicads today...

Thanks guys,

Richie


easily cleaned with Q-tip and WD-40

Hyjinx

Hi Rich
Thread still catches attention. And it has been very helpful. I have a few considerations on your experience.
I think you are on the right track with dissimilar chemistry on the goo formation. May be hiding in recesses after all the clean up and getting out still a bit in these initial runs.?
I have used Klotz bean oil and techniplate both. The bean oil in warmer temps and the t plate mostly.
Mixed well with methanol and does not separate in cold temps.
I am sure others will opine on this forum.
It is a great reference.
Friendly helpful folks here.
Welcome
Aaron-

MYHELL99

My Feedback: (47)

Thanks Aaron!

I've mostly read the whole thread. So much to learn from. I've made many pages of notes, lol.

It's just surprising to me that the crud keeps coming. After I tore it down, I reassembled with WD-40, ran it for 20 minutes, used Marvel Mystery Oil and aquarium pump after an overnight shut down, and then running for another 20 minutes the next day. I'm still getting this in my exhaust after about 40 minutes running since cleaned. I just got the Klotz in the mail, and used it for after run after the second run. I haven't had a chance to fire it up because of all this wonderful weather we're getting across the US.

-Richie

Maxam

My Feedback: (62)

Richie, when you add the air tool oil it should be allowed to drain out of a bottom valve guide. Drain and do it again while turning the propeller then air pump it. Also make sure you have castor in your fuel to protect those cam tracts. You will need to lean the engine forward/ down to drain out any oil sitting in one of the lower pistons. You do not store the engine with a ton of oil in it. Was there rust on the piston rings? -Tom

Hyjinx

Can't do better than Tom chiming in. The man is a Guru.
I use WD 40 in my radials for overwinter storage. Some of my motors have to live out in the garage unfortunately.
I run them full of WD thru the carb until it's spitting heavy out the exhaust with a starter directly out of a gallon of WD.
Then hang them nose down to pool oil around the cam/ bearing points.
Blow it out the same way with fresh fuel and good to go.
Burning the residual Wd makes the black sludge but dosent last long into the running.
Has worked for me...

MYHELL99

My Feedback: (47)

Tom,

Thanks for your reply! I didn't drain out the oil on the first restart since last year. I did store it with all the oil I injected in it. The last time I ran it (with marvel mystery oil added the night before), I drained as much as possible but did not tilt it. I even blew compressed air into one of the top cam followers to allow the oil to drain below quicker. I figured any residual oil will eventually blow out the exhaust, which it did. I was still puzzled when running after rebuild with the engine cleand and "dry", while the exhaust still had so much sludge.

This is my first radial. Is it critical to drain as much after run oil right after squirting it in? I've just never done that to my other glow engines before.

It makes sense to tilt the engine forward to get additional oil out but being bolted down to the table, I opted not to do it. I will disconnect the engine from my run table and tilt it over tonight and let any residual oil wick out prior to my next run session and hope things clear up.

So let me understand the procedure:
After flying, apply after run oil through upper cam follower. Drain. Repeat. Drain.
Connect the air pump overnight on lower cam follower port with carb open.
Disconnect air pump next day and re-install cam followers and pushrods.
I'm good until next flying session.

Do I have it correct?

The piston rings were corrosion free. There was some corrosion around the main bearing.

-Richie

Maxam

My Feedback: (62)

OK, your procedure is good till the next flying session. For long term storage, remove each glow plug and add air tool oil to each cylinder. Just 3 or 4 drops and then rotate the prop a few turns. The TRUE indicator that the engine is properly oiled and drained is in two days the engine should feel smooth as silk when turned. no "sandy" feeling.

MYHELL99

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Thanks gents for the replies. I'll report back after a few more runs on it.

Richie

MYHELL99

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Quick update on my 7-77. I changed my after run to Klotz techniplate and the exhaust globules are gone! I've also been draining the engine now and following Tom's advice with the air pump and castor in the fuel. It still feels just a little "crunchy" when I turn it over. I believe the bearing is compromised from corrosion over the winter and will need replacement at some point. Ughhh...

This baby still needs a home, and I'm thinking of pulling the trigger on the Austars-model 2.2M T-28.

I've also successfully used a 8000mah 2S LIPO battery stepped down using a Castle BEC PRO to 5.9v going into the McDaniels glow driver with great success. The BEC is pulling 8A when on, and rated at 15A continuous. The wires are as short as I could make them.

The engine is pretty close to the 3 hour mark of running and is getting better compression. I do have a question, though. It's running perfect with glow on all the time. As soon as I turn off the glow power, it richens up a lot and loses lots of power. If I lean it out, the engine will run really good (almost as good as with glow power on) but, now it's getting hot. Head temps are getting over 200 degrees F during WOT. (4800RPM MA 24x10 wood)

Are these temps what you guys are seeing? Is this a function of the OEM carb?

I do have an OS carb on order through activepowersports.com but it's backordered. If anyone has an OS carb they'd like to sell, please PM me! :-)

I appreciate this thread!

-Richie

Maxam

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The bearings might "smooth out" after awhile. When you hold the propeller tips and rock them left and right, is there play? If obvious play you will need new bearings.

MYHELL99

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No, zero play.

What type of head temps do you recall measuring at full throttle?

Thanks,
Richie

Maxam

My Feedback: (62)

200 is a bit high. Your glow should not be on above idle. You are advancing the ignition point too far with the glow on higher throttle settings causing excessive heat.

Hyjinx

Hey TomA quick thought.
I was lead to believe by a glo plug producer (Eldon from Wizard brand plugs) that once ignited the plugs burn at a constant rate depending on the RPM of the subject engine. Also indicates the dual plug set up on the early Saito Radials lights itself without being lit with a battery pre start up.
How would allowing the glo driver to operate abive idle have any appreciable effect on pre detonation timing assuming that Eldon is correct and the plugs stay lit of thier own accord?
Am I missing something here? My Evo 7-77 does not require glo at any point except initial start and runs in the high 180-200 range.

BobH

My Feedback: (2)

It's been my long understanding that a glow plug once lit via a battery should stay lit on its own. The Platinum on the coil in the plug is mostly responsible for that.

manu_cc

Bonjour à tous,
Je viens de monter un Waco avec un UMS 7-77.
Des que je pourrais je partagerais Photos et vidéos.
Manu

manu_cc

Voici le 7-77 vendu par UMS,
réchauffeur Microsens, Hélice Xoar 24x10

BobH

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Nice looking Waco. Which waco is it?

manu_cc

Waco phoenix model, que j'ai ré entoilé et repeint à l'oracolor

Hyjinx

Beautiful Waco
My brother in law flys a Phoenix. The upgraded paint is magnificent. The 7-77 is perfect in the cowl and still visible. Looks like a nice fit.
Congratulations.
Great work there.

Linkan2

Hi everyone who likes radial motors. This PT17 turns 10 years old this June. it now has 240 flight passes, is still active. And how much I have learned about radial motors. thanks for all the great posts on this page. Lars

Maxam

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Wow! A message from good ol' Lars. Hey lars, my old radials are still going strong too! I am now loosing count but my 9-90 has now over 300 flights. I did have to replace a cam track in my old 7-70. Castor / synthetic mix for oil is important. You certainly was one of the best contributors on this forum! I hope you are well with good health. -Tom

Linkan2

Thanks Tom it's good with me, I live a good retirement life now. With a lot of flights. I also changed the cam disc on my 7-35.


The new one is from the updated engine with black cylinder heads.
Which are made in one piece.
Lars

slskn

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Hello Tom, still flying the Ziroli Corsair with the nine cylinder you fixed for me, and the seven cylinder Flair Stearman, engines are running great!! Hope you are doing well, glad to still see your postings!! Take care!! Happy flying!!
Steve Pully.

Maxam

My Feedback: (62)

Thanks Steve for your reply! I am now building a 1-2.2 scale Schlundt Fly Baby with the Moki 257. Radials are a good healthy sickness! Happy to hear you are enjoying your planes. -Tom

manu_cc

Pour la lubrification du chemin de cam des nouveaux avec les culasse noirs, vous utilisez quoi, de l'huile ou de la graisse ?
D'origine il y avait de la graisse blanche, je suis en train de faire la révision du mien, et j'hésite entre huile ou graisse.
Merci