Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: rsihnhold on June 19, 2014, 07:32:23 pm

Title: Boost and EGT Sensor Locations
Post by: rsihnhold on June 19, 2014, 07:32:23 pm
I've received my GlowShift 3in1 gauge kit and now have to begin installing everything.

I need a 1/8" NPT port for the boost sensor.  It looks like there are ports on the turbo up-pipe that goes to the aftercooler and right before the flexible connection over the top of the engine.  Is this what everyone else has been using?

I don't see a ready made connection for the EGT sensor, also 1/8" NPT.  For the people who have a EGT gauge, have you tapped into the exhaust manifold or have you had a bung welded into the turbo down pipe?

Lastly, the wiring for the gauges is designed for a typical run in a much smaller/shorter vehicle.  Is there a preferred method or type of wire recommended for extending the runs?

Thanks in advance.
Title: Re: Boost and EGT Sensor Locations
Post by: John Haygarth on June 19, 2014, 08:26:58 pm
 For the EGT one I am pretty sure that Banks put that one below the turbo by drilling and tapping into that "box like" mount for turbo. You will have to remove turbo and plug the ports to keep metal out.
JohnH
Title: Re: Boost and EGT Sensor Locations
Post by: pocketchange on June 19, 2014, 08:47:29 pm
For ease of installation put the EGT sensor near the turbo intruder/manifold interface (before exhaust goes into the turbo.) 
For pressure readings, someplace handy in the intake and not in the way will work.
None of this is written in stone and understand that this question has been discussed for decades.
FWIW.. I do not have any concern for these gauges with my FT, but that is just me.

This is how I plumbed my hot rod..
My S2 Buick has the heat (O2) sensor(s) located in the collectors (down stream of the turbo about 3') and the pressure sensor is in the top rear of the intake manifold.  To verify individual cylinder temps, heat sensitive paint is close to all exhaust ports.  pc


Title: Re: Boost and EGT Sensor Locations
Post by: Barry & Cindy on June 19, 2014, 10:33:26 pm
We installed VEI boost & EGT pyrometer gauges earlier this year. Pyrometer photo is attached.
VEI Systems (http://www.veisystems.com/ws/)

I could not bring myself to drill & tap our cast iron exhaust manifold, knowing that steel shavings can fall into manifold and possibly damage turbo. Or if an unlikely pyrometer breakage happens, it would likely damage turbo. Not to mention cracking exhaust manifold from drill & tap.

So we drilled a hole in the top of the 4" steel pipe attached to the output side of the turbo. We made our hole in a place that that does not have any part of the turbo inside the pipe. We drilled a hole in a large hose clamp to hold the pyrometer in place. Photos attached.

After reading about your GlowShift purchase, I went to their web site and while looking at their gauges, found a better pyrometer bracket than my drilled hose clamp. I purchased it and it arrived today and it looks like it will make a better mounting than we now have.
http://www.glowshiftdirect.com/egt-bracket.aspx (http://www.glowshiftdirect.com/egt-bracket.aspx)

Pyrometer thermocouple probes like we have are made with dissimilar metals that produce a variable millivolt signal based upon probe temperature.
Diesel Forum - TheDieselStop.com (http://www.thedieselstop.com/forums/f25/myth-extending-pyrometer-lead-wires-) 110519/

My experience with a Cyberdyne EGT gauge was that extending these wires need to be done with the same dissimilar metal with splices carefully made. The EGT meter contains an adjustable controller that converts the millivolt to a meter reading. This controller needs to be calibrated, often by putting thermocouple in ice water and then boiling water because these two temperatures are known points. My previous pyrometer required this calibration.. When I purchased this older pyrometer, the seller asked how long of an extension I needed and he said he would connect the thermocouple and extension to the meter and he would calibrate the meter. I was never satisfied I had the correct EGT readout, even after the ice water & boiling water trick.

My new VEI pyrometer thermocouple has its controller in the engine compartment which is permanently attached to the thermocouple. The required calibration is done by the manufacturing process and no further calibration is needed. Since the controller is far from driver's position, ordinary automotive wires are used to connect controller to dash gauge, which transfers the output of the controller to the gauge without introducing any errors.

I did contact Glow Shift on how to extend their pyrometer and was told ordinary automotive wires can be used, but I believe that their controller is located in the gauge, so I am not sure I received correct information. Installation does not mention anything about extending wires with specific wires and there is no mention of re-calibration. So I have no idea how their system is designed. They do sell a set of extension wires, but offer little information on which products they are to be used for.

Here is an interesting pyrometer article:
Banks Power | Why EGT is Important (http://bankspower.com/techarticles/show/25-why-egt-is-important)

Our turbo output to intercooler & intake manifold casting does have those same 1/8" NPT fittings and that is what we used for turbo psi sensor.

Years ago we ran a bunch of spare wires from engine to dash area.  We used some of them to connect our turbo & EGT senders to the dash. Probably Foretravel spare wires could also be used.
Title: Re: Boost and EGT Sensor Locations
Post by: rsihnhold on June 20, 2014, 09:24:05 am
John and pc,
That probably is the best way to do it.  I had the turbo off when I replaced the exhaust manifold and it is mostly quick and easy to remove except for 1 screw that is incredibly difficult to access.  I guess this is going to come down to how lazy I am about this since Barry's clamp looks easy.   

Barry,
When I talked to Glowshift tech help before purchasing the unit, they said to use 16-18 gauge or larger to compensate for the resistance over the wire run but nothing special needed to be done and that they had sold quite a few to Rvers with no complaints. 

The gauges themselves are in the controller so the splices and wiring will have to transmit the data accurately over 30 ft before it gets turned into a reading.  Sounds like VEI uses a much more accurate system with the engine room controller.  I'll test this thing with before and after the addition of the splices to see how similar the readings are.  Thanks for your post.
Title: Re: Boost and EGT Sensor Locations
Post by: John Haygarth on June 20, 2014, 11:18:26 am
 Barry, as I mentioned in earlier posting you must take off Turbo etc to do the drill and tap for unit. Banks did ours (when PO had coach about 6 yrs ago ) and it has not been a problem-cracking etc as you mention. I agree with the article from Banks that this Pyrometer is a very handy tool to have and as it mentions the computer (Ottermind) controls this function (temp') very well. It is also one of the main reasons I put my air Deflector over the air intakes as I had seen so many Air Filter containers chock full of debris. Mine is still clean after replacing it in 2010!! The air restriction guage has never moved and I have actually taken filter out to check-being very careful not to cause any problems. It is a light grey colour. When at FT a couple years ago I spoke to a tech there about this item and he said that generally the container is full of everything except the "kitchen sink"!!
johnH
Title: Re: Boost and EGT Sensor Locations
Post by: rsihnhold on June 20, 2014, 11:47:04 am
Barry, as I mentioned in earlier posting you must take off Turbo etc to do the drill and tap for unit. Banks did ours (when PO had coach about 6 yrs ago ) and it has not been a problem-cracking etc as you mention.
johnH

I will say that the instructions that came with the Glowshift gauge include 3 different methods of mounting the pyrometer including before the turbo (threaded into exhaust manifold like john has), after the turbo in the turbo exhaust down pipe (like Barry has), and mounted what looks to be anywhere in the exhaust system tubing.

The order above seems to coincide with what would give the most accurate readings with regards to safe EGT since the temperature will go up the closer you mount it to the combustion chamber.  The order above is probably also in the correct order as to difficulty of installation. 
Title: Re: Boost and EGT Sensor Locations
Post by: Dave Katsuki on June 21, 2014, 02:43:18 am
When I installed our pyrometer, I was concerned not only about the potential  breakage of the probe and the chips if in front of the turbo, but also didn't want to create any local stress concentration with the hole, since the exhaust manifolds on the 8.3 and ISC engines have a tendency to crack, so I welded a tapped bung into the down pipe just after the turbo.  The Banks pyrometer comes with a long (50') thermocouple cable with the right dissimilar conductors, and I ran the cable up to the front along with the  1/8" tubing for the (mechanical) boost gauge.