Engine/Transmission (1998.5 - 2002) Burned up my engine today

[jaybigboy34]

After reading this long but very informative post, I would like some imput on whether to unplug my power puck or not when towing? I am not sure how much advanced timing the puck has. Does anyone know if it is mild or wild? I only have 15000miles on the truck, and I sure need it to last me a long time

 

[Cliffman]

That’s right, I'm back in the saddle again and how sweet it is Oo. A big thanks to Blair Pine, Chris Sutton and Dave. I couldn't have done it with out you guys. I don't believe that advanced timing is what caused #6 to melt. I believe it was 1 of 2 things, either a faulty injector or a faulty thermocouple. I have a feeling it was the thermocouple for a couple of reasons. 1) I pressure washed my engine just before my trip. Water my have gotten into the SPA connections causing the pyro to be a little off. 2) When I was pulling the hill I noticed my boost was 3 psi higher then normal. 3) I pull right on the edge of disaster, 1300-1350 degrees. 4) #6 piston runs a little hotter than the others. Given all these facts I simply believe the thermocouple was off maybe 100 degrees and since #6 runs hotter than the others it melted. I tell ya one thing; I’m not pulling at those temps anymore. 1200-1250 max from now on. I have the exhaust manifold tapped and the 2nd thermocouple installed. All I have left to do is run the wire and a switch. I’ll keep you guys posted on the difference between the two.

 

[Robin]

This has been a really good thread. I got real antsy about exhaust gas temps after I had the power turned up a couple of years ago by Diesel Injection of Pittsburgh. On a cool day I can get 36# boost, but the EGT can easily go over 1350.



I already had a pyrometer but was not trusting it. So I put a new one in, a set, thermocouple and gauge. I was right, the old one was reading about 150 degrees low. On the dashboard gauge set, I had an oil temp gauge I wasn't using, so I replaced it with a second pyrometer. The thermocouples are in the back manifold pretty close to each other. They read within a needles' width of each other. I may replace both, maybe stagger; one, then the other a year or so later.



I think it advisable not to mix and match thermocouples and gauges.



BTW, years ago, like 45, I learned never to wash an engine. I cringe when I watch a friend of mine slop Gunk all over his gasoline engine then hose it down. The only one to see my engine is me, so I just wipe off superficial grunge. But then I only wash the truck itself maybe twice a year.



Glad it all finally worked out for you, Cliffman. It kind of put a big hole in the year for you.



Bob KU8C

 

[Robin]

And another thing.



About pyrometers, some may not be aware that it is inadvisable to splice thermocouple wires. Splices, crimp or solder, introduce more junctions which can add to or reduce the voltage seen by the gauge. Get a thermocouple that is too long and coil up the excess.



Come to think of it, I think I'll look into a commercial quality pyrometer.



Bob KU8C

 

[WestTN]

a thought on the ETH

I have finally read this entire thread and have a thought on the possible reason. Cummins obviously changed more than the compression ratio to gain that additional 10hp, since they also made the injector smaller. My guess is they also advanced the timing as far as they were comfortable to get it. And it looks like they probably got it all! My truck has 62,500 miles on it. When the warranty runs out, I think I will go with injectors and boost fooler only. If I need more, I'll reduce the compression and add a box.

 

[Cliffman]

Re: What are you guys up to?

Originally posted by DHayden

Oh yeah, I also learned that if and when I do need to rebuild I'm going to o-ring the head, get those sweet pistons and send it all to cliffman to do :--)

LMFAO at DHayden. I'll never go through that again. Just added up the cost of the rebuild. $8000. 00 :--) :--) :--) :--) Give or take a few hundred...



Update: revised cost of rebuild-$9200. 00

 

[jaybigboy34]

Can anybody help me out with my question? Cliffman, glad to see you are back in business. I am very interested in seeing what those #6 temps are.

 

[tbrudder]

Originally posted by Robin

And another thing.



About pyrometers, some may not be aware that it is inadvisable to splice thermocouple wires. Splices, crimp or solder, introduce more junctions which can add to or reduce the voltage seen by the gauge. Get a thermocouple that is too long and coil up the excess.

Good advice, but not completely accurate, if I recall correctly. The Seebeck Effect is the governing principle here--the junction of two dissimilar metals (I'm relatively certain we're all using K-type thermocouples, so these metals would be alumel and chromel) will generate a voltage proportional to the temperature of the junction. The law of intermediate metals says you can use wires to extend the thermocouple wires with no effect, but the junctions of these wires must be at the same temperature. I imagine they'd need to be the same length, too, as resistance is proportional to length, and we're talking about millivolts here.



My DiPricol gauge came with 6" or so of wire on the probe, and the extension wire to the gauge. The leads had screw/bolt fittings on them, and a big piece of heatshrink to cover the junctions once made. Not sure exactly how the cold junction is made here--I haven't played with thermocouples since my physics lab days back in school, and we usually used an ice bath for our cold reference.



That said, I don't think I'd try lengthening the thermocouple leads with copper wire to save a few bucks--accuracy is too important in this application. You can always buy K-type thermocouple wire, after all, and make your extensions with that.



And if you're interested:

http://en.wikipedia.org/wiki/Thermocouple



--Ty

 

[jaybigboy34]

Can anybody answer my question about the power puck?

Thanks

 

[hammersley]

In Summary - will towing with an OLD VA Box

be a problem, if you keep the EGT's in check?????

 

[CFAR]

tbrudder

Most pyro install instructions I have seen state very clearly that the gauge is calibrated for that length of wire, don't cut excess etc... .

 

[Cliffman]

Not on SPA guages...

 

[ThrottleJockey]

Jaybigboy34



IF you STILL have a question, dude, you need to reread this thread!

 

[tbrudder]

CFAR,



You're basically right--messing with the wire will probably screw up your EGT readings. That's not to say the gauge is calibrated to the length of the wire, though--if you really know what you're doing with a thermocouple (not saying I do ), you should be able to add length to the wire without affecting the gauge accuracy adversely.



Basically, the thermocouple produces a tiny, tiny voltage change for any given temperature change, which the gauge can measure. Mucking around with the wire (splicing, soldering, lengthening, etc) can add resistance, make another thermocouple junction, etc. It doesn't take a lot to screw it up, when we're talking EMF in the millivolts.



So yeah, a guy really used to working with thermocouples could probably extend the wires 50' and still do okay, but for the rest of us, it's better to pay $20 for a longer thermocouple lead.



--Ty

 

[ChrisOlson]

Edge Comp

Hey cliffman



Very sorry to read about your engine and I am glad to read that you are back together.



I have a Question though about the Edge Comp I am looking at the Product brochure and every picture has a truck towing a big ole trailer. they tout "power to tow" and they also tout "the modules moniter temp and trans slippage and will control fueling to make sure your truck does not exceed its limits" they do say you should install gauges.



I have been a proud TDR Member and a Cummins owner for over a year now and come to rely on the wisdom of this site and its members for my techinal advice.



my driving usage is daily drving and a trip across country and back every year. this year I will be pulling about about 5000 lbs trailer and cargo to my trip to maryland and back to alaska.



I dearly love the power that the edge comp gives me, and I am a firm believer in prenvitve maintence. and take painstaking care

of my Cummins. but after reading of your troubles there is a small amount of concern now. it used to be the lift pump but gauges and having a spare eased my concern. now it is the #6

cylinder



My question? how concerned should I really be?? all comments welcome.

 

[Cliffman]

Chirs, I just completed the installation of a 2nd thermocouple installed right in front of #6 exhaust port. I'll be pulling my 15k 5'er in about 2 weeks and I'll post the difference between the average of 4, 5 and 6 and just 6. Until then don't go over 1200 and you'll be fine.

 

[OTRPU]

See ya at Muncie?



Cheers,

Steve J.

 

[jaybigboy34]

Cliffman, do you have any EGT numbers yet with that second thermocouple?

 

[Cliffman]

I don't have anything pulling yet but unloaded it's 80-90 degrees differance. Problem is #6 probe is closer to the head then the other probe. But heat is heat right!

 

[willyslover]

degrees are higher in the #6 reading I assume LOL