Question about pyrometers for testing - PeachParts Mercedes-Benz Forum

Diesel Dan · #1 12-08-2006, 03:02 PM

I am tracking down an overheating problem in one of my vehicles, and it was recommended that I check coolant temps directly to rule out a malfunctioning dash guage. I'm wondering which testing device I should get:

Here is the first example:
http://www.testequipmentdepot.com/fluke/thermometers/62.htm

From my understanding, this will measure the surface temperature of the
radiator hose. I wonder how much heat is lost between the actual
liquid, and the outside of the hose? I've found other
pyrometers/thermometers that have a submersible probe (such as this:

http://www.testequipmentdepot.com/tif/hvac/7000.htm),

which I assume would be more accurate, but more of a hassle to use, if not perhaps impossible, since you could not properly seal the hose to the fitting,
and would thus have water/steam all over the place?

Anyone?

Thanks

bgkast · #2 12-08-2006, 03:29 PM

I would go with that first one. Using it on the head or block, as well as the hose (hose will only be hot if the 'stat is open) should be accurate.

Shorebilly · #3 12-08-2006, 06:13 PM

The Fluke is a good instrument...

You can use that to check many things, besides radiator temperatures.....

Exhaust temp from each cylinder
Exhaust temp before and after turbo
jacket (cooling) water temp at each cylinder
AC freon temps before and after condenser
you could use it to spot hot spots on the sides of the crankcase (main bearings)
you could use it to check your home's circuit breakers for hot ones
you can check your house for insulation defects
wheel bearings just after you stop or from another car while running
the possible uses are many

there will not be all that much difference in temperature from the coolant within the radiator or hoses and the surface temperature......where are all of those thermo scholars when you need them??

I think that's a good price as well

SB

Dubyagee · #4 12-08-2006, 06:49 PM

We have a Fluke at work and it works great. We also have access to a Agema 1000 FLIR that makes looking for hot spots really easy.

Eskimo · #5 12-11-2006, 06:15 PM

I like the Raytek Autopro ST25. The Tool Warehouse has them for <$115, shipping included.

The "spot" being sampled is about 1/2" across at a distance of 8" from the unit - a bit smaller than that of the Fluke 62 mentioned earlier in the thread. It uses two intersecting visible beams to give a visual reference for when one is 8" from the target.

kip Foss · #6 12-11-2006, 08:37 PM

If you are not going to make your living off this thermometer you might check Harbor Freight. I think they have a similar one for much less.

kerry · #7 12-11-2006, 08:54 PM

I got a Harbor Freight one for around $40 I think. It works well. It's great for cooking as well as wrenching. Might even work for some medical diagnostics, not to mention figuring out if the woman on the next barstool is really hot for you.