Jake experts?

[Tom-D]

Would this be the case for the R-755?

No. because the oil may be in the intake pipe of the lower cylinder, and the engine at exhaust event for that cylinder.

the starter will turn the engine at normal speed building energy until that cylinder reaches its intake stroke and draws in the oil, and continue to turn at normal speed until it contacts the solid mass.

The energy contained in the prop and rotation group will be enough to bend a rod before the starter clutch feels the resistance.

 

[Clark1961]

Another brilliant contribution regarding radial engines. Well done.

And ya might wanna add a specialist to help you with that OCD.

 

[DouglasBader]

You're still contributing to the thread, adding all kinds of input on radial engine operation, aren't you?

You aren't.

 

[Tom-D]

You're still contributing to the thread, adding all kinds of input on radial engine operation, aren't you?

You aren't.

Tell us again how much all your bragging about how much experience you have helped the owner of the Jake? If he did follow your advice and turned the Jake with the starter he would now be buying a new Jacobs 275 for his 195.

 

[denverpilot]

http://www.thepocket.com/wavs/calmly.wav

 

[DouglasBader]

If he did follow your advice and turned the Jake with the starter he would now be buying a new Jacobs 275 for his 195.

At NO time did I ever counsel him to use the starter.

Your reading comprehension skills lack.

Tell us again how much all your bragging about how much experience you have helped the owner of the Jake?

My commentary regards radial engines and their operation. Most of what's been posted doesn't, and isn't at all germain to the thread. Mostly whining about what others are perceived to have said.

A small motor such as the Jacobs may be pulled through by hand to check for hydraulic lock. If the plugs are removed, however, pulling it through by hand or by the starter is irrelevant insofar as safety to the engine.

During the start procedure, one should always turn the engine through with the starter and motor a given number of blades before applying fuel or spark.

 

[wsuffa]

OK, knock off the personal comments ALL of you. Posts on topic are OK, posts that are aimed at folks personally are not.

 

[bluerooster]

I'm not a round engine guy, but I'm starting to get involved in a C-195 here at the airpark.

The plane was not flown for 6 weeks and enough oil drained into the bottom cylinders to wind up in the intakes.

He was told to remove a plug from the bottom cylinders and run the engine to get rid of the oil.

Isn't there a check valve in the oil pump that should have prevented this?

There is a "clean kit" installed on the engine if this has a bearing.

Thanks
Paul
N1431A
N83803
2AZ1

It's a radial engine. The bottom cylinders will get oil in them when it sits not running. I don't care what you do. What oil is in the crankcase will gravitationaly follow the path of least resistance. It will creep through the gaps in the piston rings into the combustion chamber. If there happens to be a valve open, it will creep into either the exhaust, or intake.

After we sold the T-50, the new owner went out, pulled it through a couple of blades on each engine. Hopped in and fired up, promptly blowing a jug through the cowling, and bouncing it accross the tarmac. It had been sitting for about 4 days.
While we owned it, Dad would pull it through at least 7 blades, more likely 9, for each engine.

We had an Ag Cat, that sat for a year or so, and I hadda pull it through at least 20 blades, before I was satisfied to start it without blowin' a jug.
There was oil streaming from the exhaust stack. (should'a pulled the plugs, ended up doing so anyway, as they were oil fouled)

 

[bluerooster]

No, it's not, and it was standard procedure for us on the R2800's, R2600's, R3350's, and R4360's.

Bump the starter. If it doesn't move and the clutch slips, there's hydraulic lock.

Pull a 4360 through by hand and you stand a very good chance of doing internal damage.



Your statement is wrong. By saying "all radials do not" you make the statement that no radials do have a clutch in the starter. This is not true.....

I took it to mean that not all radials have....

And I don't know about 195s, but the Jakes on the T-50 do not have 2 mags.

 

[bluerooster]

Tell us again how much all your bragging about how much experience you have helped the owner of the Jake? If he did follow your advice and turned the Jake with the starter he would now be buying a new Jacobs 275 for his 195.

Mabe not, if he took it upon himself to remove the plugs first.

 

[DouglasBader]

Precisely.

How'd you like the Bamboo Bomber?

 

[Tom-D]

At NO time did I ever counsel him to use the starter.

Your reading comprehension skills lack.

you said in post #6

There's nowhere to put such a valve. The design of the engine means that oil will often end up in the bottom cylinders.

Pulling the engine through by hand is often the wrong choice, depending on the engine. In many cases, it's safer to use the starter motor, because if there's a hydraulic lock, the starter clutch will slip, protecting the engine. One can do damage on some engines when pulling through by hand.

My commentary regards radial engines and their operation. Most of what's been posted doesn't, and isn't at all germain to the thread. Mostly whining about what others are perceived to have said.

A small motor such as the Jacobs may be pulled through by hand to check for hydraulic lock. If the plugs are removed, however, pulling it through by hand or by the starter is irrelevant insofar as safety to the engine. bull scat that is absolutely wrong.

During the start procedure, one should always turn the engine through with the starter and motor a given number of blades before applying fuel or spark.

NEVER EVER hit the starter button any radial that you have not checked for oil in the bottom cylinders.

your advice seems to have changed since you posted #6

 

[Tom-D]

It's a radial engine. The bottom cylinders will get oil in them when it sits not running. I don't care what you do. What oil is in the crankcase will gravitationaly follow the path of least resistance. It will creep through the gaps in the piston rings into the combustion chamber. If there happens to be a valve open, it will creep into either the exhaust, or intake.

After we sold the T-50, the new owner went out, pulled it through a couple of blades on each engine. Hopped in and fired up, promptly blowing a jug through the cowling, and bouncing it accross the tarmac. It had been sitting for about 4 days.
While we owned it, Dad would pull it through at least 7 blades, more likely 9, for each engine.

We had an Ag Cat, that sat for a year or so, and I hadda pull it through at least 20 blades, before I was satisfied to start it without blowin' a jug.
There was oil streaming from the exhaust stack. (should'a pulled the plugs, ended up doing so anyway, as they were oil fouled)

Couple things you should realize.

1. oil does not enter the cylinder thru the top of the cylinder skirt and drain around the rings.the cylinder skirt is higher than the push rod tubes, or the oil sump.

2 new radial engines like the P&W 985 do not leak or blow smoke on start.

3. My radial does not leak, nor does it use oil. it will run 35 hours on a qt oil 25W65

 

[DouglasBader]

NEVER EVER hit the starter button any radial that you have not checked for oil in the bottom cylinders.

It's a standard procedure to do so in radial engines that utilize clutch-equipped starters.

I'd have had my butt kicked (and I'd have been fired) if I tried to pull the engines through by hand. It was very much policy that the starter be used, and for good reason.

your advice seems to have changed since you posted #6

Nothing has changed: my posts have always been consistent, and my statements true and correct, including post #6.

 

[Tom-D]

It's a standard procedure to do so in radial engines that utilize clutch-equipped starters.

Does a Jacobs 275 have a clutched starter? That was the subject of the OPs first post.

I have had my butt kicked (and I'd have been fired) if I tried to pull the engines through by hand. It was very much policy that the starter be used, and for good reason.

Do you know how much a P&W rotating group weighs? do you know what force it would create by inertial energy it carries when it is rotating at starter speeds?

nothing has changed: my posts have always been consistent, and my statements true and correct, including post #6.

No one else reads you that way.

 

[DouglasBader]

Does a Jacobs 275 have a clutched starter?

Did I say it did? Show me the place where I said that. Can you do that?

Do you know how much a P&W rotating group weighs? do you know what force it would create by inertial energy it carries when it is rotating at starter speeds?

Piston radials turn over very slowly on the starter, hence our absolute requirement in certain equipment to pull it through on the starter, and not by hand. If the clutch is set properly, it's going to do no damage, whereas pulling the long arm of the propeller through on those engines will...hence the clutch, you see.

It's there for a reason.

I don't think I said anything about P&W rotating groups. You did, though.

No one else reads you that way.

You're the spokesman for all now?l Self-appointment doesn't become you.

The moderator has asked you to keep your comments related to the thread. Are you able?

 

[Clark1961]

The moderator has asked you to keep your comments related to the thread.

No the moderator did not type thqt.

 

[Tom-D]

Did I say it did? Show me the place where I said that. Can you do that?

My question was did you know, I think we know the answer by your evading the answer.

radials turn over very slowly on the starter, hence our absolute requirement in certain equipment to pull it through on the starter, and not by hand. If the clutch is set properly, it's going to do no damage, whereas pulling the long arm of the propeller through on those engines will...hence the clutch, you see.

Do you realize there is a gear reduction in the nose of the big radials? which gives the engine crank shaft a big advantage. but there is nothing between the starter and the engine except the clutch, if fails and you have a ruined engine.

It's there for a reason.

yep to protect stupid pilots

I don't think I said anything about P&W rotating groups. You did, though.

yep, I did because you don't seem to realize the energy that can be stored in them.

You're the spokesman for all now?l Self-appointment doesn't become you.
The moderator has asked you to keep your comments related to the thread. Are you able?

All I do is expose the BS. and speak for no one but me.

 

[timwinters]

 

[AdamZ]

Really folks this is pretty sad. Someone asks a reasonable question about engines and there are still multiple people who cannot resist turning this into a spitting match. If people can't be respectful then they really should just refrain from posting. Being wrong or having a different opinion is not license to lob grenades at one another.

 

[CJones]

I don't know anything about radials. That said, I just saw an episode of "Ice Pilots" where they were getting a DC-4 ready for a trip. It had been sitting for about a month and they pulled the bottom plugs and ran the engines for a little while to clear the oil.

I saw that re-run last night. It was pretty cool seeing the 'open' cylinders firing.

 

[Tom-D]

I saw that re-run last night. It was pretty cool seeing the 'open' cylinders firing.

The 1340 will run with one row of plugs out. There is a device that is called a "blow out plug" it's basically a valve that allows the cylinder to blow out but not to allow the intake stroke to suck any thing back into the cylinder thru the spark plug hole.
They are used on the first start after preservation to get the yucky stuff out of the cylinders.