AC 175 Diesel question  
       
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        Category:  Allis Chalmers
       Forum Name:  Farm Equipment
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       URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=187233
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      Topic: AC 175 Diesel question
       
      Posted By: TomYaz
       Subject: AC 175 Diesel question
       Date Posted: 23 Mar 2022 at 6:26pm
       
      
        
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So I used the tractor for the first time...first time I owned a diesel tractor. 
 
 Notice a lot of smoke? coming out the vent tube  off the head.  Is that normal?  Exhaust seems fine. 
 
 Also noticed the tractor seems to run a little hot.  Otherwise runs fine. 
 
 Friend said there may be a connection between the two. Said replace the thermostat.  
 
 Lastly is there a way to adjust the remote ram lift rate?  The valve seems very touchy..goes up in a hurry, too fast to my liking. 
 
 Thanks 
 
 tom 
 
 
 
 
 
 
 
 
  ------------- If its not an All-Crop, it all crap!
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  Replies: 
       
      Posted By: AC720Man
       
      Date Posted: 23 Mar 2022 at 6:45pm
       
      
        
          
	
Do you mean out of the hose attached to the valve Cover? If its white like a fog its blow by. As a engine ages this is a normal occurrence. How many hours are on it? At what temperature is the gauge at when you say its hot? 170-180 degrees would be a normal range.
  ------------- 1968 B-208, 1976 720 (2 of them)Danco brush hog, single bottom plow,52" snow thrower, belly mower,rear tine tiller, rear blade, front blade, 57"sickle bar,1983 917 hydro, 1968 7hp sno-bee, 1968 190XTD
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      Posted By: TomYaz
       
      Date Posted: 23 Mar 2022 at 6:55pm
       
      
        
          
	
  AC720Man wrote:
  Do you mean out of the hose attached to the valve Cover? If its white like a fog its blow by. As a engine ages this is a normal occurrence. How many hours are on it? At what temperature is the gauge at when you say its hot? 170-180 degrees would be a normal range. |   
 
 Yes thats what I am talking about.  It is white.  Hours are under 2000's if to be believed.  Cant remember the temp exactly but I know it was right on the "red zone"...will have to make a note of it next time. 
 
 Thanks for the response. 
 
 
 
 Sorry I meant hours in the 2000's , not under. 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: AC720Man
       
      Date Posted: 23 Mar 2022 at 7:13pm
       
      
        
          
	
Tom that’s very low hours if the tach works and its original. Simple things first. Have you checked the antifreeze level? Pull the oil dipstick, is it clean oil or is it white and foamy?
  ------------- 1968 B-208, 1976 720 (2 of them)Danco brush hog, single bottom plow,52" snow thrower, belly mower,rear tine tiller, rear blade, front blade, 57"sickle bar,1983 917 hydro, 1968 7hp sno-bee, 1968 190XTD
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      Posted By: TomYaz
       
      Date Posted: 23 Mar 2022 at 7:21pm
       
      
        
          
	
  AC720Man wrote:
  Tom that’s very low hours if the tach works and its original. Simple things first. Have you checked the antifreeze level? Pull the oil dipstick, is it clean oil or is it white and foamy? |   
 
 Yep tach works.  Dont think it rolled over as the tractor is in decent shape. 
 
 Will check the dipstick 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: BrianC
       
      Date Posted: 23 Mar 2022 at 7:25pm
       
      
        
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 The gauge or electric sender (if it has one) may be off. Verify actual coolant temperature with an infrared thermometer, or cooking thermometer. Calibrate thermometer 
  with boiling water, that would be 212F. 
 
 Blow-by could be worn engine.
  If it were a gas engine I would do a compression test first thing. With a diesel, you have to pull the injectors. Need an adapter to fit the situation. Then the fuel line will leak when you put it back together.
  
 
 I don't know much about the 170/175 3pt lift. I think all the valves, linkages and lift cylinders are external. It could be linkage that is rusted up or stuck with dirt. Get an owners manual and read if there is a response control of some sort.
  
 
 
 
 
  
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      Posted By: soggybottomboy
       
      Date Posted: 23 Mar 2022 at 10:31pm
       
      
        
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Make the easiest checks first. Engine oil and coolant level as mentioned. Then make sure the fanbelt is tight. If those are ok, put in a new thermostat as mentioned. If that doesn't change anything then take the radiator off and have it cleaned by a radiator shop if you can find one. If you should happen to need a new radiator, get one with an extra set of rows(thicker)and then put a larger driven pully on the fan to slow it down. That quiets the fan noise and makes that model more pleasant to drive.
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      Posted By: injpumpEd
       
      Date Posted: 24 Mar 2022 at 7:55am
       
      
        
          
	
Sounds to me like a bad head gasket, and the blowby is steam. 
  ------------- 210 "too hot to farm" puller, part of the "insane pumpkin posse". Owner of Guenther Heritage Diesel, specializing in fuel injection systems on heritage era tractors. stock rebuilds to all out pullers!
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      Posted By: TomYaz
       
      Date Posted: 24 Mar 2022 at 8:03am
       
      
        
          
	
Lots of suggestions/advice.  Thanks for the input. 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: TomYaz
       
      Date Posted: 27 Mar 2022 at 2:50pm
       
      
        
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Ok a small update. 
 
 Oil looks fine, no water.  If I am to believe the temp gauge it was running at 220F wihle not really working...just spraying 100 gal at slow speed. 
 
 Next step is to drain the coolant and see if I was low. 
 
 Tom 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: DSeries4
       
      Date Posted: 27 Mar 2022 at 4:04pm
       
      
        
          
	
I would also get the rad boiled out.  220 Doing light duty work is not right.  How's the water pump? I run a 180 degree thermostat and it never moves past the middle of the green zone, regardless of what I am doing.
  ------------- '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
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      Posted By: TomYaz
       
      Date Posted: 27 Mar 2022 at 5:04pm
       
      
        
          
	
  DSeries4 wrote:
  I would also get the rad boiled out.  220 Doing light duty work is not right.  How's the water pump? I run a 180 degree thermostat and it never moves past the middle of the green zone, regardless of what I am doing. |   
 
 
 
 Not sure...I guess no way if knowing unless you rip it out and examine.  Will be on the checklist if not resolved... 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: DrAllis
       
      Date Posted: 27 Mar 2022 at 6:25pm
       
      
        
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The radiator must be FULL. By that I mean a couple inches from the very top. This means crawling up on the tire and checking it. With the engine off and stone COLD, turn on the key. The temp gauge should be clear DOWN in the cold range. Engine running wide open throttle for 20 minutes or more the temp gauge should barely be at the bottom of the green and no more. 220 degrees should technically be puking some out the overflow. I do not think it is that hot, bad gauge and sender but prove it instead of tearing things apart.
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      Posted By: TomYaz
       
      Date Posted: 27 Mar 2022 at 6:35pm
       
      
        
          
	
Yep will do that, and get a temp gauge...bought one last year from harbor freight...where the heck did I put it???
  ------------- If its not an All-Crop, it all crap!
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      Posted By: TomYaz
       
      Date Posted: 29 Mar 2022 at 6:52am
       
      
        
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Folks, 
 
 Next step is to check the coolant level. Regardless if low or not going to replace the fluid as have no idea if when was ever done. 
 
 Question: where is the best place to drain coolant?  I am going to assume a valve on bottom of radiator, but is there another place as well?   Service manual is silent. 
 
 Thanks 
 
 Tom 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: DSeries4
       
      Date Posted: 29 Mar 2022 at 9:27am
       
      
        
          
	
  TomYaz wrote:
  Folks,
 
 Next step is to check the coolant level. Regardless if low or not going to replace the fluid as have no idea if when was ever done. 
 
 Question: where is the best place to drain coolant?  I am going to assume a valve on bottom of radiator, but is there another place as well?   Service manual is silent. 
 
 Thanks 
 
 Tom  |    
 
 
 Right side of the engine block under the primary fuel filter.  Also should be a drain at the bottom of the rad - on the engine side.
  
  ------------- '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
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      Posted By: TomYaz
       
      Date Posted: 29 Mar 2022 at 9:34am
       
      
        
          
	
Thanks!
  ------------- If its not an All-Crop, it all crap!
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      Posted By: TomYaz
       
      Date Posted: 29 Mar 2022 at 5:22pm
       
      
        
          
	
Well, the coolant level was about 3" below the filler neck....no core showing...what I was able to collect  was about 10 pints; but some of it missed the bucket.  Manual says 13 pints.  So dont think I was too low?
  ------------- If its not an All-Crop, it all crap!
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      Posted By: DrAllis
       
      Date Posted: 29 Mar 2022 at 5:46pm
       
      
        
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Be careful refilling with coolant !!  I think those Perkins will air lock if you don't do it right. If you drained 13 quarts it HOLDS 13 or more quarts to be full.
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      Posted By: TomYaz
       
      Date Posted: 29 Mar 2022 at 8:03pm
       
      
        
          
	
  DrAllis wrote:
  Be careful refilling with coolant !!  I think those Perkins will air lock if you don't do it right. If you drained 13 quarts it HOLDS 13 or more quarts to be full. |   
 
 
 
 Care to explain how to do it right?  All I know is to pour in radiator... 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: DrAllis
       
      Date Posted: 29 Mar 2022 at 8:39pm
       
      
        
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My 175 owners manual says 15 quarts...2 inches down in the radiator, not 3,  If you get 13 or more quarts in it, you're probably good to go. Fill slowly. Maybe have the nose up in the air to help burp it. Owners manual says nothing but I know there is a possibility, but again if you pour in the proper amount that means it's full.
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      Posted By: TomYaz
       
      Date Posted: 29 Mar 2022 at 8:43pm
       
      
        
          
	
I think you mean pints?  My service manual says 13 pints and I drained around  13 pints give or take.
  ------------- If its not an All-Crop, it all crap!
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      Posted By: TomYaz
       
      Date Posted: 29 Mar 2022 at 8:47pm
       
      
        
          
	
Dont have my service manual with me but wonder if the 13 pints is capacity of just the radiator.  
  ------------- If its not an All-Crop, it all crap!
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      Posted By: DrAllis
       
      Date Posted: 30 Mar 2022 at 5:44am
       
      
        
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15 QUARTS for the entire system. Same for gas and deezel tractors.
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      Posted By: BigGuy1000
       
      Date Posted: 30 Mar 2022 at 7:56am
       
      
        
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Yes 15 QUARTS not pints! And drain is on right side under the bottom of the fuel filter!!!! Drain also on bottom left inside corner of radiator!! 
  
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      Posted By: TomYaz
       
      Date Posted: 30 Mar 2022 at 8:02am
       
      
        
          
	
  BigGuy1000 wrote:
  Yes 15 QUARTS not pints!And drain is on right side under the bottom of the fuel filter!!!! Drain also on bottom left inside corner of radiator!! 
 
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 Yep found the drains... 
 
 Did the block plug first... 
 
 Then radiator....but radiator was emptied by block plug as nothing came out. .. 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: John m
       
      Date Posted: 30 Mar 2022 at 8:40am
       
      
        
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Hopefully the radiator drain is not plugged up.
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      Posted By: TomYaz
       
      Date Posted: 30 Mar 2022 at 8:42am
       
      
        
          
	
got a couple drips  and thats it.
  ------------- If its not an All-Crop, it all crap!
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      Posted By: TomYaz
       
      Date Posted: 30 Mar 2022 at 8:43am
       
      
        
          
	
will test when I do the flush
  ------------- If its not an All-Crop, it all crap!
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      Posted By: DrAllis
       
      Date Posted: 30 Mar 2022 at 9:04am
       
      
        
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With the radiator cap OFF and drain cock OPEN use a rubber tip blow gun and gently give it some air.
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      Posted By: TomYaz
       
      Date Posted: 01 Apr 2022 at 5:54pm
       
      
        
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Well, 
 
 I drained and refilled the radiator with water....And doc the radiator drain cock was plugged.  Your compressed air tip worked like a charm...Started her up (man this tractor will NOT start when even in 50's temperature!)  and now she wont go past 150F.  So I suspect the problem was lack of coolant.  Drained it out and was like chocolate.  Going to refill it partially to get the temp up high enough to force the thermostat open so we can circulate and drain again.  The blowby doesnt seem as bad... 
  ------------- If its not an All-Crop, it all crap!
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      Posted By: DSeries4
       
      Date Posted: 01 Apr 2022 at 10:11pm
       
      
        
          
	
  TomYaz wrote:
  Well,
 
 I drained and refilled the radiator with water....And doc the radiator drain cock was plugged.  Your compressed air tip worked like a charm...Started her up (man this tractor will NOT start when even in 50's temperature!)  and now she wont go past 150F.  So I suspect the problem was lack of coolant.  Drained it out and was like chocolate.  Going to refill it partially to get the temp up high enough to force the thermostat open so we can circulate and drain again.  The blowby doesnt seem as bad...  |    
 
 
 Like I said earlier, I would get that rad flushed and boiled out to get all of that chocolate out of there!   You might want to run the engine with some dish soap for a while to clean up the block too! 
 
 
  ------------- '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
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