|
|
|
#1
|
||||
|
||||
Will this work for EGT probe?
Ran across this while looking for something else, I'm wondering if it can be used as an EGT probe...
They're only $10 shipped, and I don't mind using my multimeter (includes K-type thermocouple)...
__________________
Ich liebe meine Autos! 1991 Mercedes-Benz 560SEL | Megasquirt MS3-Pro | 722.6 transmission w/ AMG paddles | Feind Motorsports Sway Bar | Stinger VIP Radar | AntiLaser Priority | PLX Wideband O2 | 150A Alternator | Cat Delete 1981 Mercedes-Benz 300SD | Blown engine, rebuilding someday... 1981 Mercedes-Benz 300SD | Rear ended, retired in garage. 2009 Yamaha AR230HO | Das Boot Excessive speeding? It ain't excessive till I redline! |
#2
|
||||
|
||||
It could work, but you wound need to calibrate it. X ohms of resistance on your multi-meter won't mean much otherwise.
__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver 1982 300SD - 232K miles - Wife's Daily Driver 1986 560SL - Wife's red speed machine |
#3
|
||||
|
||||
That one is a type-K thermocouple, and my multimeter has a built in type-K thermocouple, so theres no calibration involved. Thermocouples generate voltage, not current. I'm working on a circuit that uses a MAX6675 and a microcontroller to interface it to USB now (all parts where free samples )...
I'm just wondering whether the probe is long enough to give an accurate EGT and not a exhaust manifold temp...
__________________
Ich liebe meine Autos! 1991 Mercedes-Benz 560SEL | Megasquirt MS3-Pro | 722.6 transmission w/ AMG paddles | Feind Motorsports Sway Bar | Stinger VIP Radar | AntiLaser Priority | PLX Wideband O2 | 150A Alternator | Cat Delete 1981 Mercedes-Benz 300SD | Blown engine, rebuilding someday... 1981 Mercedes-Benz 300SD | Rear ended, retired in garage. 2009 Yamaha AR230HO | Das Boot Excessive speeding? It ain't excessive till I redline! |
#4
|
||||
|
||||
That should work. I don't know whether the exhaust manifold on your engine has any available tapped holes; in any case, you would have to re-tap to use the 1/4 inch thread of the thermocouple.
For best results, the thermocouple must be out in the exhaust stream. The EGT probe in my '85 300D-T was initially used with an adapter that kept most of the probe in the metal of the fittings and the manifold and consequently read on the low side (max about 800F). The "upgraded" version uses a shorter fitting and, when installed in my '87 300D Turbo, should read more accurately. Jeremy
__________________
"Buster" in the '95 Our all-Diesel family 1996 E300D (W210) . .338,000 miles Wife's car 2005 E320 CDI . . 113,000 miles My car Santa Rosa population 176,762 (2022) Total. . . . . . . . . . . . 627,762 "Oh lord won't you buy me a Mercedes Benz." -- Janis Joplin, October 1, 1970 |
#5
|
||||
|
||||
Quote:
I think thermocouples produce resistance
__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver 1982 300SD - 232K miles - Wife's Daily Driver 1986 560SL - Wife's red speed machine |
#6
|
||||
|
||||
For the price of 10$ you could get five of them for each exhaust port and then average them on a single display.
__________________
Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac? As long as they would add one additional commandment for you to keep thy religion to thyself. George Carlin (Wonder where he is now..) 1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won. pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt. |
#7
|
||||
|
||||
Quote:
wow let us know, thats a great price. Most likely the guages are calibrated for K type as well. I dont thnk J types work well at higher temps.
__________________
1982 300CD Turbo (Otis, "ups & downs") parts for sale 2003 TJ with Hemi (to go anywhere, quickly) sold 2001 Excursion Powerstroke (to go dependably) 1970 Mustang 428SCJ (to go fast) 1962 Corvette LS1 (to go in style) 2001 Schwinn Grape Krate 10spd (if all else fails) |
#8
|
||||
|
||||
Theres a ton of them on ebay if you guys are interested...
http://search.ebay.com/search/search.dll?sofocus=bs&sbrftog=1&dfsp=32&catref=C6&from=R40&satitle=K+Type+Thermocouple+Temperature+Probe&sacat=-1%26catref%3DC6&sargn=-1%26saslc%3D2&sadis=200&fpos=ZIP%2FPostal&sabfmts=1&ftrt=1&ftrv=1&saprclo=&saprchi=&fsop=32%26fsoo%3D2&coaction=compare&copagenum=1&coentrypage=search I'm starting to doubt that these will work for EGT, the probe is only 1/2in long, too far out of the exhaust stream. But why are EGT probes so much more expensive?..Its basically the same construction, just with a longer probe..
__________________
Ich liebe meine Autos! 1991 Mercedes-Benz 560SEL | Megasquirt MS3-Pro | 722.6 transmission w/ AMG paddles | Feind Motorsports Sway Bar | Stinger VIP Radar | AntiLaser Priority | PLX Wideband O2 | 150A Alternator | Cat Delete 1981 Mercedes-Benz 300SD | Blown engine, rebuilding someday... 1981 Mercedes-Benz 300SD | Rear ended, retired in garage. 2009 Yamaha AR230HO | Das Boot Excessive speeding? It ain't excessive till I redline! |
#9
|
||||
|
||||
Quote:
http://www.azom.com/details.asp?ArticleID=1208#_How_They_Work Thermistors are the ones with varying resistance.
__________________
Ich liebe meine Autos! 1991 Mercedes-Benz 560SEL | Megasquirt MS3-Pro | 722.6 transmission w/ AMG paddles | Feind Motorsports Sway Bar | Stinger VIP Radar | AntiLaser Priority | PLX Wideband O2 | 150A Alternator | Cat Delete 1981 Mercedes-Benz 300SD | Blown engine, rebuilding someday... 1981 Mercedes-Benz 300SD | Rear ended, retired in garage. 2009 Yamaha AR230HO | Das Boot Excessive speeding? It ain't excessive till I redline! |
#10
|
||||
|
||||
Quote:
seems like it should be plenty long enough. the walls onthe manifold arent that thick. just try to put it on the outside wall of a turn and the boundary layer there should be pretty thin.
__________________
1982 300CD Turbo (Otis, "ups & downs") parts for sale 2003 TJ with Hemi (to go anywhere, quickly) sold 2001 Excursion Powerstroke (to go dependably) 1970 Mustang 428SCJ (to go fast) 1962 Corvette LS1 (to go in style) 2001 Schwinn Grape Krate 10spd (if all else fails) |
#11
|
||||
|
||||
Quote:
An EGT probe you may want to try is this one . Some folks on the VW forum have had good luck with them, and they are fairly cheap as well. Keep us posted!
__________________
John Robbins '05 E320 CDI - 240k '87 300TD - 318k |
#12
|
||||
|
||||
I think that with that you will be measuring the temperature of the manifold more that the exhaust. If you look at a proper EGT thermocouple, they extend at least to the center of the flow. What you have is right on the edge, and its likely that it will not give you a true measure of EGT.
__________________
For Sale: 1982 MB 300TD 1995 Chevrolet Suburban 6.5TD Sold: 1980 IH Scout Traveler- Nissan SD33T Diesel |
#13
|
||||
|
||||
That thermocouple looks like it measures from the tip which should extend plenty into the exhaust stream for a good reading.
__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver 1982 300SD - 232K miles - Wife's Daily Driver 1986 560SL - Wife's red speed machine |
#14
|
||||
|
||||
Quote:
I'm using a Microchip PIC18F4553, it has a built in USB serial port device that can be accessed easily from C code. I'm making a Car PC out of parts of a broken media center PC (mini-ITX) I got for free. The screen is going to be mounted in a hollowed out sun visor and heres a preview of the display I'm working on... If I can find a good way to read a thermistor and calculate out the extreme non-linearity, I'll be making one for oil and tranny temp, and I'll probably be making ones for oil/tranny pressures too, using these things makes adding gauges so cheap, I can't believe noones thought of it before... The only parts I can't get as free samples or junkyard parts are the circuit board and thermocouple, the rest is in software...
__________________
Ich liebe meine Autos! 1991 Mercedes-Benz 560SEL | Megasquirt MS3-Pro | 722.6 transmission w/ AMG paddles | Feind Motorsports Sway Bar | Stinger VIP Radar | AntiLaser Priority | PLX Wideband O2 | 150A Alternator | Cat Delete 1981 Mercedes-Benz 300SD | Blown engine, rebuilding someday... 1981 Mercedes-Benz 300SD | Rear ended, retired in garage. 2009 Yamaha AR230HO | Das Boot Excessive speeding? It ain't excessive till I redline! Last edited by 300SD81; 07-03-2008 at 04:51 PM. |
#15
|
||||
|
||||
Quote:
Quote:
If you're looking for PCB mfgrs.. I know of two good ones. http://www.pcbfabexpress.com/ http://www.4pcb.com/ PCB Fab Express used to be a lot better than they are now... its been about two years since I've used them. G'luck and let me know if you need anything
__________________
John Robbins '05 E320 CDI - 240k '87 300TD - 318k |
Bookmarks |
|
|