Anyone know where i can buy a dual port 2in pyrometer gauge with the thermocouples for a 8v92. the DD have it but i don't like the price. thanks
Pyrometers are not specific to any application. Some aircraft used a single gauge to monitor EGT of up to 8 cylinders using a basic rotary switch. Each cylinder could be monitored to determine general condition.
There are also many makers of probes. Get a pyrometer and a probe and experiment. Compare a pyro to a IR temp tool. Frank
Frank i do not doubt what your are saying but my exhaust manifolds have places for the probes and calls for a grounded type k probe.the main problem i am having is the 2" dual read out gauge as most are 3 or 31/2" and if anyone knows where to find it the guys on this board will but thanks for the info gives me another option
Try van dusen aircraft supply, not that expensive. John
I purchased my large 3" duel pyro-boost gage (1500 degree, 35 psi boost) with senders at Fleet Speedometer in Bakersfield. Try your local phonebook looking for the heavy duty oriented auto parts stores or speciality vendors. I found what I needed at a speedometer shop. Go figure. Also try your local, friendly, $inexpensive$ heavy truck wrecking yards. Good luck. :) :) :)
Unless you have really pumped up that 8V-92Ta with over 100 size injectors, the pyrometer is just not needed. Especially if you have an electronic engine-the 2 stroke engine just doesn't get hot enough to worry about exhaust temperature-that's one of the main reasons they worked so well in buses-didn't have to worry about them burning up from lugging. Good Luck, TomC
Tom i have a DDEC and just want to monitor both sides of the engine but if i can not find a 2in dual read out gauge i am going to forget it
There's another good reason to have a pyrometer, other than protecting the engine. You can improve your fuel economy -- sometimes dramatically -- by picking a "red line" temperature and staying below it.
FWIW.
Don
I had a pyrometer from VDO. I don't know if they have dual readings gauges. Here is a link.
http://www.siemensvdo.com/products_solutions/special-oem-solutions/instrumentation/viewline/52mm_instruments/pyrometer/pyrometer.htm
Do you know that the wire between the thermocouple and the gauge is special and cannot be spliced?
Ed Roelle
Flint, MI
Yes, i do Ed the one at the DD dealer has a special harness that goes to the gauge from each thermocoupling and thanks for the link as i have VDO gauges in my dash
Go to the Isspro site. Isspro.com I think. We've used them in our trucks for 50 years. Everything you need is available at this site including the 40 foot long leads and the pickup that screws into your exhaust pipe. Cheap too.
A pyrometer is really about the only gauge on the dash that will tell you if you loose your water on a non computer engine and give you a chance to save your engine.
A water temp gauge will read cold as soon as it looses fluid contact.
I know on my transit that if my water level is low, my buzzer comes on. Having the buzzer respond to low water level, high water temp, low oil pressure, low air pressure has saved me and the engine enough times where I'll NEVER disconnect the buzzer.
I know that the only one position that the OEM's would mount a pyrometer is after the turbo. Nothing was mounted before because of fear that the bulb might break off and go through the turbo ruining it. There's enough history of this happening to make me think of is it really worth having the two pyrometers to watch the exhaust temp that will most likely never get critically hot and possibly having to buy a new turbo if the bulb breaks off? I wouldn't. Good Luck, TomC
Tom I guess Prevost and DD don't know about the problem it would cause because thats where I got my idea from and both manifolds in my Eagle have a place for the probes and what good would a dual read out be on the turbo exhaust
New and others,
If your exhaust became restrictive due to plugging or installing the wrong muffler, wouldn't the inlet and outlet temps for the turbo increase a lot?
I have a temp sender in my oil pan and in my differential. Both lines run to a selector switch and the diff side also turns on a small red light to indicate "normal" position is disabled. FWIW
I also installed oil pres and over temp water senders along with my analogs. I wired the idiots to a buzzer and a BIG red light but put them through a switch. The switch had a little red light that indicated when the sw was off. My procedure is to turn off the alarm and then start the engine and then switch over to "active" mode when oil pressure comes up. As simple as I could do it and I feel safe. FWIW
John
So Tom is your point that a post-turbo mounted pyro is useless? We had this debate over on TheDieselStop several times & I ended up putting in a pre-turbo pyro on both my Powersmoke diesels but I haven't put a pyro on the moneypit - yet. I've always wondered what the point of a post turbo pyro was - by the time the exhaust gets that far its getting pretty cold so the question is, what should you use as a trigger temp. I thought that most people used a rule of thumb of 900-1000 post-turbo being equivalent to 12-1300 pre-turbo. But, like I said, I concluded the last time I went through this discussion that there wasn't much point putting a pyro behind the turbo and I'm not wild about putting one ahead of it either. My Powersmoke was a pretty smooth ride compared with the 8-92 - I'd be a lot more worried about losing a pyro tip on this engine.
Vertually every OEM truck Pyro is mounted after the turbo. Now the temp for the particulate trap is right on it (replaces the muffler).
I say (pre 9/11) the generating power plant on Kauai, Hawaii. They had Wartsilla engines that were straight 8's that were 2 stories tall. They had an individual pyrometer per cyliner, total pyrometer and a tachometer for the turbocharger! Now that's neet. Good Luck, TomC
I had a cummins that had the pyro pickup post turbo and it worked quite welll showing temps to 1300 degrees. Jerry
A pyro is great for dubugging Jakes (finding which side's solenoid is either stuck open or not turning on at all). One half runs cooler than the other. Twin pyros also can show a side (assuming a ''v" type engine) running hot due to high fuel injection (like a stuck injector or a slipped rack).
Of course having one behind the turbo makes this impossible as a diagnostic tool (as the different tempurature exhaust gasses would get mixed, and the tempuratures averaged).
I've heard of others using a pyrometer to determine combusion efficiency (over-fueling should have fuel continuing to burn as the exhaust valves open - thereby increasing the temperature in the exhaust manifold). This temperature increase appears faster than the transfer of heat from the cylider jackets to the cooling water (and thus the water tempurature reading), and roughly the same time as black smoke would be working through the exhaust system. This should be good if you do a lot of grades - you can tell when it's time to back off the throttle and down shift (this is how the Bank's computer upgrades work supposedly).
-Tim
Quote from: Tim Strommen on November 18, 2007, 02:12:25 PM
I've heard of others using a pyrometer to determine combusion efficiency (over-fueling should have fuel continuing to burn as the exhaust valves open - thereby increasing the temperature in the exhaust manifold). This temperature increase appears faster than the transfer of heat from the cylinder jackets to the cooling water (and thus the water temperature reading), and roughly the same time as black smoke would be working through the exhaust system. This should be good if you do a lot of grades - you can tell when it's time to back off the throttle and down shift (this is how the Bank's computer upgrade work supposedly).
-Tim
This is how we used our pyrometer. When climbing a grade, I watch tach and pyrometer. As RPM drops, EGT rises. When EGT is 750-800 (RPM is usually around 1500), we downshift bringing RPM up to about 2000 and EGT drops to about 500. Jack
Post turbo pyro senders do have their place and in my opinion, the ideal setup would include 2, the primary in the normal position between the head and the turbo and the secondary placed close to, but outboard from the turbo on the down/out side of the turbine. A properly marked two position switch would be required next to the boost/pyro gage.
This way you can analyze all sorts of problems within the mill and the turbo itself and also keep an eye on changing conditions with the exhaust back pressure/temperature situation which can explain/indicate muffler or spart arrestor conditions. I for one enjoy having all that stuff available on the dashboard although 99% of the time it would be ignored. :) :) :)
Henry,
I am with you....I want all the data I can imagine cause it only has to come into play once to justify the expense.
I had a vac gauge that i watched all the time so I would get better MPG and I installed an inclinometer for finding a level patch in the "space dujour" and save me some time setting up. I saw an inch less of vac than i should have at 55mph and my incl. said dead level. I stopped to check tires and found a hot rear axle. 25 mph for the remaining 15 miles into Sioux Falls and the shop found a fried bearing. Mech said that mine was the first rear bearing replacement job he ever saw where the driver "caught" the problem in time to prevent serious damage to the axle and tube. Yeah, I like all the data I can get.
John
****Of course having one behind the turbo makes this impossible as a diagnostic tool (as the different tempurature exhaust gasses would get mixed, and the tempuratures averaged****
And that is the intent of the pyro in our usage - there are other diagnostics available to measure other parameters of exhaust gases and resulting inefficiencies - FWIW