3 Engine Help Questions
04-03-2005 | 06:17 PM
#1
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From: Williamstown,
WV
3 Engine Help Questions
I was just running some engines awhile ago, and noticed this:
1. My .91 FX is Rich, but it is hot when i touch the head after running it,
2. My .91FX Makes a "click" sound after the piston goes up near the head after the engine is run, and
3. My .91FX has less compression than my OS .50SX, is this right? Thanks!!
1. My .91 FX is Rich, but it is hot when i touch the head after running it,
2. My .91FX Makes a "click" sound after the piston goes up near the head after the engine is run, and
3. My .91FX has less compression than my OS .50SX, is this right? Thanks!!
04-03-2005 | 06:32 PM
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From: Johns Creek,
GA
RE: 3 Engine Help Questions
You might want to give people more than 11 minutes to respond
Sorry I do not have an answer for you,
but relax.....you will get one soon...
Just remember this is a board...not a chat room
Sorry I do not have an answer for you,
but relax.....you will get one soon...
Just remember this is a board...not a chat room
04-03-2005 | 06:59 PM
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From: Kirkland,
WA
RE: 3 Engine Help Questions
1) I would be more concerned if it wasn't hot. Hot is a relitive term. You can only hold your finger on about 130 deg. f.
2) The click is just the crank going over TDC. Don't worry unless it clunks.
3) The 90 is a ringed engine and the 50 is ABC or N. The 90 will not produce its full compression unless running.
Quit worrying and go fly.
2) The click is just the crank going over TDC. Don't worry unless it clunks.
3) The 90 is a ringed engine and the 50 is ABC or N. The 90 will not produce its full compression unless running.
Quit worrying and go fly.
04-03-2005 | 08:47 PM
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From: Mary Esther, Florida, FL
RE: 3 Engine Help Questions
BARCC:
I usually don't respond to OS threads, but it looks like DaveH, FBD, and W8YE are off somewhere else. Along with all the rest who might give an answer.
Even with a rich run, 200F is not excessive. Up to 250F is still OK. 275F is getting to the dangerous point, specially if you're not using castor oil or a castor blend. Back when I was running C/L speed we'd let the engines run around 350F with pure castor oil.
On this one I'd pull the back plate and check the connecting rod. A loose fitting rod is about the only thing that will cause a click in a two stroke engine that runs fine otherwise.
Perceived compression is dependent on many things. Among them are the size of the lever you use to turn it (the prop) and the port timings of the two engines. If the 91 has 91 power the compression is fine.
Bill.
I usually don't respond to OS threads, but it looks like DaveH, FBD, and W8YE are off somewhere else. Along with all the rest who might give an answer.
1. My .91 FX is Rich, but it is hot when i touch the head after running it,
2. My .91FX Makes a "click" sound after the piston goes up near the head after the engine is run.
3. My .91FX has less compression than my OS .50SX, is this right?
Bill.
