Heat gauge-how hot is hot?
Heat gauge-how hot is hot?
I have a heat gauge off an early 80's ultralight with a free air engine. This gauge shows the beginning of red line hot as 450 deg F. Does that sound right?
81 Liquifire
80 Trailfire 440
72 500
79&80 el Tigre 6000
80 Trailfire 440
72 500
79&80 el Tigre 6000
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harleysportster
- Posts: 2965
- Joined: Thu Jul 14, 2005 12:00 am
- Real Name: Pat Scott
- Location: Southeast Pa.
Re: Heat gauge-how hot is hot?
What part of the engine was the sensor located? A water cooled liquifre will run around 140ish.
'76 440 cyclone
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
Re: Heat gauge-how hot is hot?
This is the twpe where a washer sits under a spark plug and a connected wire goes to a gauge. It was on a free air two-cycle.
81 Liquifire
80 Trailfire 440
72 500
79&80 el Tigre 6000
80 Trailfire 440
72 500
79&80 el Tigre 6000
-
harleysportster
- Posts: 2965
- Joined: Thu Jul 14, 2005 12:00 am
- Real Name: Pat Scott
- Location: Southeast Pa.
Re: Heat gauge-how hot is hot?
It sounds like the sensor is picking up the combustion temp or the temp of the head. For a free air engine, the red-line could be correct for that type of gauge.
'76 440 cyclone
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
Re: Heat gauge-how hot is hot?
Ok with a little research I will answer my own question. According to Rotax and the gauge manufacturer, an axle fan two-cycle, such as a 503, should have a cylinder head temp (CHT) of 350-375F. Anything in excess of 400-425F is "Hot". So the gauge I have showing 450F as "red line" hot is a little high and should be a little lower, maybe 425F.
I am not sure how all this relates to a free air engine. I once had a '74 el Tigre 440 free air, and if I am not mistaken, it had a stock CHT heat gauge, but did not show actual temperatures so I do not know what it ran. This engine never over heated, even in 40F weather.
I am not sure how all this relates to a free air engine. I once had a '74 el Tigre 440 free air, and if I am not mistaken, it had a stock CHT heat gauge, but did not show actual temperatures so I do not know what it ran. This engine never over heated, even in 40F weather.
81 Liquifire
80 Trailfire 440
72 500
79&80 el Tigre 6000
80 Trailfire 440
72 500
79&80 el Tigre 6000
-
ICCSF 108
- Posts: 4369
- Joined: Sun Jul 17, 2005 12:00 am
- Real Name: Kenny Heins, AKA Grumpy
- Location: Blue Springs Mo.
- Contact:
Re: Heat gauge-how hot is hot?
My Arrow brand cyl. head temp gauges show red beginning @ 450 deg.
Kenny
Kenny
AKA: Kenny, Grumpy, Mr. Richard Head
"I Hunt For it, Purchase it, Haul it, Sometimes Repair it, Sometimes Break it, Then Fix it Again, Label it, Warehouse it, Talk About it, So NOW, HOW Can I Take Any Less $$ For It?"
"God I love the smell of KLOTZ in the morning, That smell, you know that Gasoline/Oil Smell, MAKES the whole place SMELL like.. LIKE VICTORY. You know someday the 2 strokers are gonna end..."
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"I Hunt For it, Purchase it, Haul it, Sometimes Repair it, Sometimes Break it, Then Fix it Again, Label it, Warehouse it, Talk About it, So NOW, HOW Can I Take Any Less $$ For It?"
"God I love the smell of KLOTZ in the morning, That smell, you know that Gasoline/Oil Smell, MAKES the whole place SMELL like.. LIKE VICTORY. You know someday the 2 strokers are gonna end..."
Do Anti-War Protesters have reunions? If so what do they TALK about?
Re: Heat gauge-how hot is hot?
450 was HOT on the Cat gauges even though they went higher on the dial.
Head temp is head temp regardless if it is F/A or F/C.
Head temp is head temp regardless if it is F/A or F/C.
Todd Schrupp
Milbank SD
Milbank SD