Testing a Temp Gauge?
Printed From: Unofficial Allis
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=154626
Printed Date: 19 May 2025 at 3:43am
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: Testing a Temp Gauge?
Posted By: Coke
Subject: Testing a Temp Gauge?
Date Posted: 07 Oct 2018 at 2:59pm
|
Is there much you can do to test a temp gauge? Just bung the end of it in a boiling pot of water? What's the thread size of the gauge, so I know what size bolt to stick in to stop all the coolant leaking out? Thanks in advance. ------------- 1957 D17 Diesel w/ M&W Pistons |
Replies:
Posted By: Reindeer
Date Posted: 07 Oct 2018 at 3:07pm
|
An infrared temp gun will take the temperature of hte housing the gauge is mounted into. Works great for verifying things. My gauge insists the temp is 160 degrees, but the thermostat is 180 degrees, and the temp gun says 179-180, which makes sense. I think the temp gun I have was 20 Canuck bucks, so probably about 15 US might get you one at Harbor Freight.
As long as I know the gauge is 20 degrees low, I am OK with running it like that. ------------- |
Posted By: DougS
Date Posted: 07 Oct 2018 at 3:21pm
|
Get your wife to buy one of those infrared temp guns for her kitchen. Problem solved and she'll not claim that you spent a red cent on your tractor. ;) |
Posted By: Coke
Date Posted: 07 Oct 2018 at 3:25pm
|
Accuracy isn't a problem for mine, it doesn't move, atall. How cool does a diesel run, without a thermostat? I suppose the infrared thing might tell me that, eh? You're assuming two things though, one I'm married, two she can cook.  ------------- 1957 D17 Diesel w/ M&W Pistons |
Posted By: Ted J
Date Posted: 07 Oct 2018 at 3:41pm
|
NEVER assume [ass/u/me] any thing!!! Yep, cheap at HF. You can use it for ALL kinds of stuff! ------------- "Allis-Express" 19?? WC / 1941 C / 1952 CA / 1956 WD45 / 1957 WD45 / 1958 D-17 |
Posted By: Alvin M
Date Posted: 07 Oct 2018 at 3:41pm
| all diesels need thermostats 180 to 190. install new gauge. what model tractor do you have |
Posted By: Coke
Date Posted: 07 Oct 2018 at 4:02pm
That's good because I was planning on getting a set of SAE wrenches from there, I have an incomplete Sears set, and some pipe wrenches, and metric, of course, for some reason I have 3 17mm wrenches, I don't know why, or how?
1957 D17 Diesel, sorry I forget that some versions of the site, like mobile?, don't show my signature (which has the model etc. in it.) And it has M&W pistons, which I believe is a thing? I was meaning tho' does anyone know how hot a diesel gets, if someone has pulled out the thermostat, I believe that happens a lot on old machines, farmers being thrifty et al. ------------- 1957 D17 Diesel w/ M&W Pistons |
Ted J wrote:Posted By: Coke
Date Posted: 07 Oct 2018 at 4:20pm
|
@Ted J, do I want the $11.99 one or the $19.99 one? http://https://www.harborfreight.com/non-contact-pocket-thermometer-93983.html" rel="nofollow - https://www.harborfreight.com/non-contact-pocket-thermometer-93983.html" rel="nofollow - https://www.harborfreight.com/non-contact-pocket-thermometer-93983.html https://www.harborfreight.com/infrared-thermometer-93984.html" rel="nofollow - https://www.harborfreight.com/infrared-thermometer-93984.html ------------- 1957 D17 Diesel w/ M&W Pistons |
Posted By: Jim.ME
Date Posted: 07 Oct 2018 at 4:29pm
| How hot the engine will get without a thermostat is basically a function of how hard you work it for how long. It could run for hours with no load and not get hot. In theory it could reach the same temperatures as one with a thermostat if run hard and long enough. The thermostat aids getting it up to operating temperature quicker, and keep it up there. As Alvin M posted, diesels need a thermostat in the 180 to 190 range. And it is best for gas engines to have them, of the correct temperature range, as well. |
Posted By: Jim.ME
Date Posted: 07 Oct 2018 at 4:36pm
| The 230 degree top end range of the 11.99 one is too close to the temps you may read on a cooling system. The 19.99 one has a top end of 482 degrees. I would go with the 19.99 one, it can be used for other checks needing higher temperature readings. |
Posted By: DiyDave
Date Posted: 07 Oct 2018 at 6:14pm
go with the higher end one. You can always use it to check bearings, and lotsa other stuff...
|
Posted By: Butch(OH)
Date Posted: 08 Oct 2018 at 8:36am
|
Water boils at 212 at sea level and goes down about 1 degree for every 500 feet above. Since that falls into the upper operational range of the gauge, is cheap and easy to do I wouldn't further complicate it myself |
Posted By: Alvin M
Date Posted: 08 Oct 2018 at 8:39am
| Water boils at 240 degrees with 7 lb radiator cap |
Posted By: DiyDave
Date Posted: 08 Oct 2018 at 5:59pm
|
Don't forget what antifreeze does to boiling point... https://goo.gl/images/XggAHo" rel="nofollow - https://goo.gl/images/XggAHo
|
Posted By: Coke
Date Posted: 08 Oct 2018 at 6:20pm
|
But putting the end of the gauge, the sensor end, in boiling water, I should expect to see a good bit of movement? Anyone know the thread size of the internal fitting? ------------- 1957 D17 Diesel w/ M&W Pistons |
Posted By: Jim.ME
Date Posted: 08 Oct 2018 at 6:52pm
|
Yes, you should see a good bit of movement if you put the sensor bulb into boiling water. It should go a bit over 200 if you have a numbered face and near the high end of the operating range if the face has ranges. The internal thread of the adapter bushing on the one I have in my spares is a loose 5/8-18 (fine thread). No guarantee another will be the same thread. |
Posted By: Butch(OH)
Date Posted: 09 Oct 2018 at 6:08am
|
Yes, just as Jim said boiling will be at the upper end of the operating range. Remove the sender bulb, borrow a pot from the ms and heat it to boiling with a propane torch and stick the bulb in it the needle should rapidly rise to the upper side of green or operating range |
Posted By: Ted J
Date Posted: 09 Oct 2018 at 7:09am
|
Yes, go with the $20 one. I like the laser dot so it is pinpoint. Add in the higher operating degrees and it's a no brainer. Water in a radiator with a 50/50 mix boils at about 220°, and a pressure cap raises that by about 2° for every pound of pressure. Here in Wisconsin, a mixture of 60% anti-freeze and 40% water gives a person the best mixture for the boiling point and also the freezing point. Hope this helps... ------------- "Allis-Express" 19?? WC / 1941 C / 1952 CA / 1956 WD45 / 1957 WD45 / 1958 D-17 |