no cylinder pressure, steam exhaust out,

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Drprez
Posts: 59
Joined: Tue Apr 02, 2019 3:55 am
Location: Las Vegas

no cylinder pressure, steam exhaust out,

Post by Drprez »

Hello

I have a chloe frame someone gave to me which has all the essentrics and all which work fine as this was once working version that they started to take apart to convert but never did..

i can run it on air no problem and can switch the reversing gear forward and backward no problem. The cylinders would work fine and the air would exhaust out the exhaust pipe.

However today, when i went to test it on air, the air only is venting out the exhaust stack, it is not filling the cylinders.

so my question is but i think i know this answer but i am asking it to be sure. are there check valves from the steam line into the steam chest? or anywhere from the steam header to the exhaust ?

If not, as i suspect what would cause the air to basically bypass the cylinders and exhaust out?

yes i have tried shifting forward and reverse but nothing seems to do the trick, i have not changed anything since it was working last but now it isnt. to me it seems like a check valve is stuck open or something. No there are no leaks in the air lines or any of the fittings i have checked them there is no air leaking.

What could it be? and how to fix this?

thanks in advance!
thanks
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Nicholas Kalair
Las Vegas, NV

...the best is yet to come...
Marty_Knox
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Re: no cylinder pressure, steam exhaust out,

Post by Marty_Knox »

When is the last time you oiled the valves and cylinders?
Mike Walsh
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Re: no cylinder pressure, steam exhaust out,

Post by Mike Walsh »

It's possible that the D-valves might be lifted off of the valve deck, allowing air to bypass into the exhaust.
Marty_Knox
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Re: no cylinder pressure, steam exhaust out,

Post by Marty_Knox »

Squirt some oil in the steam chests then hook up the air and see what happens.
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Drprez
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Location: Las Vegas

Re: no cylinder pressure, steam exhaust out,

Post by Drprez »

Ok no one answered my question though. so there are no check valves between the steam header and the exhaust then? the only valve is on the steam chest?

well i have not oiled them yet other than just with a small oil can to keep them lubricated.

How much oil should i put in the steam chest? to run on air

What are D valves? and what is the valve deck? do you mean the slide valve inside the steam chest?
if so how do you fix it so they dont lift off the deck ?
Nicholas Kalair
Las Vegas, NV

...the best is yet to come...
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Dick_Morris
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Re: no cylinder pressure, steam exhaust out,

Post by Dick_Morris »

so there are no check valves between the steam header and the exhaust then?
No, just the slide valves.
What are D valves? and what is the valve deck? do you mean the slide valve inside the steam chest?
Yes. In cross-section from the side, the valves are a D (or actually inverted U) shape. They ride on a valve face or deck where the ports are located.
if so how do you fix it so they don't lift off the deck ?
Steam pressure normally forces the valve against the valve face. A valve may have lifted off of the valve face and some sticky oil/dust kept it from reseating. Steam would normally wash some of the oil away in use, but on air you may be getting a build up of oil and dust. A little light oil or maybe a squirt of WD-40 might loosen the sticky oil. You may be able move the valve back onto the port by gently pushing with a piece of rod through the steam inlet. If not, you'll need to remove the valve covers to make sure things are clean and that the valve is a slip fit on its driver.

Here's an animation - https://www.youtube.com/watch?v=9NEm3PMHPyc
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NP317
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Re: no cylinder pressure, steam exhaust out,

Post by NP317 »

"if so how do you fix it so they don't lift off the deck ?"

The valve needs to be able to lift off the surface, to allow condensate out of the cylinder and into the exhaust port.
That can happen when cylinder cocks fail to open, or a slug of water makes it past the throttle into the cylinders.
Think of that function as a safety valve for the cylinders.
RussN
hoppercar
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Re: no cylinder pressure, steam exhaust out,

Post by hoppercar »

Sounds like your slide valves have lifted up..floated..off of the valve face...your sending air directly up the stack. If your valve fits to tight in the valve rod...this can happen....it needs a few thou. Clearance so pressure will seat it
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LVRR2095
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Re: no cylinder pressure, steam exhaust out,

Post by LVRR2095 »

Drprez,
It sounds like you are at the beginning of your time in the Live Steam hobby. All of us started out similarly and we learned with the help of folks already in this hobby. Do you live near a live steam club? If we knew where you lived possibly one of the members of this list who lives near you could visit and go through some trouble shooting with you.

Keith
Gra2472
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Re: no cylinder pressure, steam exhaust out,

Post by Gra2472 »

Have you taken the valve chests apart to have a look at the valve face and D-valves? Sounds to me like you have some dirt, grit, rust, or something even more nefarious fouling the valve. Oil is a good thing, but I would take the valve chest covers off and have a look at the valve seats before running it anymore. If it is scored badly enough from foreign contaminants you could get air passing the valve.

Garrett
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tomc
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Re: no cylinder pressure, steam exhaust out,

Post by tomc »

could the snifter valves be stuck open?

Tom C.
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