Have you had your pyrometer probe come loose??

[Hoefler]

While pulling this burn trailer home last night, I had my pyrometer blow out of the exhaust manifold. I was running about 23lbs of boost and around 1200* on the egt. And poof, out it came. I thought I had blown a exhaust gasket some where. I still had 20lbs boost but the exhaust temp was hanging around 300*. I had to drive about 3 miles before I could pull over safely. It seem to run fine except for the noise. When I check it out, the probe had blown out of the compression fitting. I put it back together and came home with out incident. I have had my gauges installed for over 30k miles and never had a problem before. Just wondering if anyone has had a similar experience.

 

[Moose Truck]

What's the drive Pressure?? It looks like you are stock, so it can't be to high. Probaly just a lose EGT Probe. Moose00

 

[sslechta]

as a matter of fact, i have had this happen to me. when i first installed the gauges, my and a buddy went out and saw what the truck could really do. the probe blew out with around 33 lbs. of boost. we just installed it back in and nearly 30,000 miles later no problems.

 

[NPloysa]

No but it does seem that I didn't thread mine in all the way. I mean I tapped all the way through the manifold, but the fitting only screwed in 1/3 of the way. I was a little worried it wouldn't catch the tapped threads but the probe itself extends far enough to get good readings. I need to run out to the truck to get my motorcycle tags so I think I will tug on it and make sure it's still tight in there!



Nick

 

[Boondocker]

I've had this happen to me a number of times, only when towing. My theory is that I tapped the hole a little too far, but I don't know how to tell. It never seems to stay tight. I think that the high/low heat cycles when towing up and down hills causes the iron manifold to expand and contract, thus loosening the thread grip until it can vibrate out.



I finally safety-wired mine. It's still not tight, but can't back out now. My ISSPRO EGT gauge has always worked well.

 

[Mikie12]

I know all too well what your talking about. When I drilled and tapped my manifold for the pyro prob, I measured the thickness of the manifold wall, then tapped alittle, and screwed in the probe sleeve to see where it stopped tight. I then compared the depth and if short, I ran the tap in more until I got it flush with the inner wall. This took several times to get just right.

When completed, I took a welder's chalk marker, and marked a line on the manifold and sleeve so I could tell at a glance if it had moved any (unscrewed)

Good luck, Michael.

 

[Hoefler]

Mine did not come out of the manifold, that part has stayed tight. The compression nut came loose and the probe came out of the ferrule that usually crimps on the line.