175 - what is this?
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Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=120232
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Topic: 175 - what is this?
Posted By: orange-is-power
Subject: 175 - what is this?
Date Posted: 11 Mar 2016 at 7:32pm
What exactly is this and what does it do? Has a line coming from top of fuel tank, one coming from up front off the air breather tube, and another line. I forget where it goes to. Just wondering. Thanks. 
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Replies:
Posted By: allisbred
Date Posted: 11 Mar 2016 at 7:44pm
| I believe this is for the air horn pre heater. Please add a few more pictures of the line route. Best regards, Kevin |
Posted By: Scooterboy
Date Posted: 11 Mar 2016 at 8:16pm
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That is a fuel manifold, part of the thermostart system. One line fuel. One line to heater. One line fuel return to tank. I never seen one in operation and I'm not saying I know much about them but I think the system ignites fuel from the heater to warm the inside of the air intake manifold.
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Posted By: DSeries4
Date Posted: 11 Mar 2016 at 8:45pm
x2. You are correct. ------------- '49 G, '54 WD45, '55 CA, '56 WD45D, '57 WD45, '58 D14, '59 D14, '60 D14, '63 D15D, '66 D15II, '66 D21II, '67 D17IV, '67 D17IVD, '67 190XTD, '73 620, '76 185, '77 175, '84 8030, '85 6080 |
Scooterboy wrote:Posted By: orange-is-power
Date Posted: 11 Mar 2016 at 9:10pm
| So it's just something to aid starting in cold weather? Does it work automatically or how/when does it get used? Every time you start the engine? It appears to be original equipment. Thanks for the replies. |
Posted By: DSeries4
Date Posted: 11 Mar 2016 at 9:17pm
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It is original equipment. It is activated when you turn the key to the "start" position and hold it for 30 seconds or a minute. It's just another kind of manifold heater.
------------- '49 G, '54 WD45, '55 CA, '56 WD45D, '57 WD45, '58 D14, '59 D14, '60 D14, '63 D15D, '66 D15II, '66 D21II, '67 D17IV, '67 D17IVD, '67 190XTD, '73 620, '76 185, '77 175, '84 8030, '85 6080 |
Posted By: Scooterboy
Date Posted: 11 Mar 2016 at 9:22pm
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I know a wire goes from the heater to the ignition switch so one would think there is a position on your ignition switch to turn the heater on when needed. Probably once the ignition switch is moved to a different function the heater would be off.
Clean the area around the heater on the intake and see if the instruction plate is there.
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Posted By: BrianC
Date Posted: 11 Mar 2016 at 9:51pm
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Yes the Perkins Thermostart system. If the 170/175 ignition key works like the 160 I have, to start the engine you turn the key all the way clockwise, then push it in, that activates the starter, right? Prior to pushing in, with the key turned fully clockwise, electric power is sent to the thermostart valve. After 30+ seconds it heats up hot enough to open a valve letting fuel dribble in, it catches on fire. Then you push it in to crank the engine. So the fires heat in the intake manifold helps start cold start. Is it better than glowplugs or high wattage intake manifold grids? Perkins have a reputation for good cold starts. I think some Fords use the system, and most of the Perkins MF tractors. Try it out, hold it clockwise 30-60 seconds, then see if that valve is warm. I don't know what could go wrong, but stuck valve, gelled fuel crud in that supply line. The valves are available. |
Posted By: Eldon (WA)
Date Posted: 11 Mar 2016 at 11:09pm
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I've got 8 of these tractors and haven't found one that worked yet.... ------------- ALLIS EXPRESS! This year: |