What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

EGT probe placement

H

hobby_rv6

Member
I am in the process of replacing my original Van's single EGT probe with a new 4 probe EGT system as part of installing the Garmin G3X package. The instuctions that come with the new Alcor EGT probes say to install the probes at least 2" below the exhaust flange in a #30 hole. I had hoped to re-use the existing probe hole, but the existing EGT probe (and hole) was considerably larger than #30 and the current hole is less than 2" below the exhaust flange.
So here are my questions:
1. Can I just use the exisiting hole? The hose clamp that holds the probe in the hole more than covers the entire existing hole. I forgot to measure, but I think that it is about 1.5" below the flange.
2. If it is absolutely imperative that the hole be 2" or greater below the flange, how can I seal the existing hole in the exhaust pipe? Use some sort of stainless patch held in place with a hose clamp?
I am open for all suggestions. Thanks.
Hobby in Abilene, TX
RV6
270 hours
 
Cut off a stainless screw of the (appropriate diameter) making it really short. put it into the hole & put a stainless clamp over it to hold it in. Ain't pretty but it'll work.
As for the distance thing, I think as long as they are all the same distance from the exhaust flange. EGT trend & comparison is key.
 
If the original holes are 1.5" I would just use them, the temp .5" lower is not going to be significantly different.
 
what did you end up doing?

hobby_rv6 said:
I am in the process of replacing my original Van's single EGT probe with a new 4 probe EGT system as part of installing the Garmin G3X package. The instuctions that come with the new Alcor EGT probes say to install the probes at least 2" below the exhaust flange in a #30 hole. I had hoped to re-use the existing probe hole, but the existing EGT probe (and hole) was considerably larger than #30 and the current hole is less than 2" below the exhaust flange.
So here are my questions:
1. Can I just use the exisiting hole? The hose clamp that holds the probe in the hole more than covers the entire existing hole. I forgot to measure, but I think that it is about 1.5" below the flange.
2. If it is absolutely imperative that the hole be 2" or greater below the flange, how can I seal the existing hole in the exhaust pipe? Use some sort of stainless patch held in place with a hose clamp?
I am open for all suggestions. Thanks.
Hobby in Abilene, TX
RV6
270 hours
Click to expand...
What did you end up doing? I'm in the same boat. We surely can not be the only folks with this issue. Seems there would be a reducer fitting, that would make the fit. Thx, DM
 
Last edited:
Go to the source

Since I still had some doubts, I talked to the man that designed and built my exhaust system, Larry Vetterman.
He patiently explained why probes are placed where they should be (think making sure that the probe is in the exhaust gas flame cone) and then suggested probe orientation, by cylinder, specific to RV's and my engine (O360-A1A) to avoid intake tubes, spark plugs, etc. Huge wealth of knowledge.
Lastly, he suggested a stainless steel counter sunk screw (1/4" long) to plug any existing holes, with a band clamp securing the screw, if you cannot use any existing hole(s).
 
Resolved

Pulled pipe. Had a professional local weld shop (familiar with welding SS aircraft exhaust pipes) put on a small patch. Putting new probe in location other than the patch. Take care. dm
 
You must log in or register to reply here.
Back
Top