Clifford's Throttle Position Sensor - Fixed

The problems I had with no Jake brake coming down from the mountains of West Virginia were due to a failing throttle position sensor (TPS).  It is like a noisy volume control on older audio equipment but since it is a sealed unit, there is no way to clean the contacts.

A couple of years ago, I removed it, worked the control through its entire range a bunch of times and basically, extended its life hoping to find a cheaper solution than the $170 replacement parts. It has worked ok since then but when I have checked the diagnostic faults log, there have been a growing number of inactive TPS faults indicating that it was getting much worse.

The TPS parts I picked up at Central Carolina Trucks in Kernersville, NC Just off of I-85/ I-40 was just a freightliner TPS and a six inch 3 wire- to-5 wire converter harness.  It took all of 15 minutes to replace it and not the estimated 2 hours shown in the parts catalog.  Easy job and now, no more TPS codes in my fault log..... and my Jake brake should work reliably from now on.

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Budd

The other shoe finally dropped

Several years ago the kitchen slideout started making a terrible rackety-clankity noise when going in or out.  At the time, I was sure the whole slide was going to end up in the street but it turned out to be a small problem that was very difficult to fix.

My mechanical slides are driven by a 12v dc motor through a gear train to a pinwheel shaft with teeth that engage cogs on the two rams.  To keep the whole thing from drifting while traveling or even when parked and extended, there is a permanent magnet and friction disk attached to the back end of the motor's drive shaft.  Very simple arrangement. This brake is wound with an electromagnet winding that activates with the motor to cancel the magnetic field of the permanent magnet so the motor shaft can turn freely.  When power to the motor stops, the electromagnet drops the cancelling magnetic field and the permanent magnet once again, clamps down on the friction disk attached to the end of the motor's drive shaft.

Unfortunately, the manufacturer used a pot metal cast adapter to fasten the brake assembly to the back of the motor. They also used only two #6 screws to fasten the adapter to the motor housing and did not use any Loctite. You guessed it.  The screws worked loose until one fell out and the whole brake unit was flopping around on the end of the motor shaft.  Lots of racket.

When I repaired the one under the kitchen slide it was some what accessible if you are small and skinny. I am 6'2 and 300 lbs. so you can imagine what a hard job this was to get finished.  They covered the heads of the attachment screws behind the brake mechanism so that had to be removed from the adapter before the adapter could be fastened back to the motor.

If you are a mechanic I know you hate engineers that do this kind of stuff.  In this case, it was hard to reach up into the belly of the RV between the axles to put the screws back in (with Loctite) but it was doable.

Guess what?  I have two slideout with this mechanism and the other one has now lost a screw and produces the terrible rackety-clankity noise when going in or out. Knowing what was wrong and how much work it was going to be to fix it I have not rushed right in to do it.

Today, I rushed in (where angels fear to tread, of course) and opened up the belly of the beast to tighten the adapter bracket back up.

Whoa! I said to myself when I had finally gotten at the motor assembly. The screws are loose but the adapter is BROKEN!  different game altogether.  Now I have to find a replacement or engineer something myself that will hold the brake assembly onto the motor housing.  Making it much worse is that there is no way to get at the screws that hold the brake to the adapter so to fix this puppy I am going to have to take the whole motor and gear box out just to tighten two #6 screws (assuming I can even find a replacement for the pot metal adapter).

So, until I can get on with it I just have to button the bottom back up to keep the critters out... but I was too pooped to do it today.... maybe tomorrow, I need to replace some of the insulation, anyway. It looks like it has been pulled out before, and just chunks stuffed back in there.  I will cut some batts to fit so it won't all come tumbling out into my face the next time I have to go into there.

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Budd

Sealing off Refer vents for Residential Refrigerator

At the beginning of the year, we replaced our defunct Norcold LM1200 12cu ft. RV refrigerator with a standard 22 cu foot Household refrigerator.  It was pretty much a test to see if we could work with it instead of a gas/elec  RV refrigerator so we just used an older extra refrigerator we kept in the basement for summer water melons and beer.
In the past 6 months of use, it has never been a problem for us and even when we have been traveling unplugged for 9 hours at a time the freezer still stayed below 15 degrees.  We are very happy with the household refer and especially with the much larger capacity and far better internal layout and flexibility it has over any RV refer we have seen.
Since this was a test, we left some of the labor to finish off the installation until we were sure we were going to like it and that it would be a completely satisfactory solution, which it is.  One of the things left to do was to seal off the outside venting that was there for the RV refrigerator.  Although I wrapped each vent door in a trash bag and pinned it shut, it looked odd and the winds on the highway shredded them pretty quickly. With them unsealed it has been like living with a window open all the time so before summer gets really hot I needed to finish this off.

The main thing I was concerned about was air infiltration. A secondary concern was just plain insulation which is problematic on the bottom vent because there is only 1” behind the refer and the air being exhausted when the refer is running needs to be able to circulate back into the interior of the RV or the compressor will overheat and it won’t cool very well.
The upper vent door was no problem and I fully insulated it with part of a bat of pink fiberglass insulation glued over the 4 mil plastic film I first glued to the backside of the door to seal out all airflow through it.
I think that this will work fine for the summer.  I may revisit this later, to see just how well it is actually sealed but short of pulling the refrigerator and sealing the hole from inside the RV I don’t see much chance of doing it any better.
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Rear Window Crud

The runoff from the rear fiberglass end cap and roof have left a really hard deposit on the rear windows.  I have tried a number of things to get it off with mixed success.
The last thing I have used is CLR, and it appears to work better than anything else.  I make it a point to really rinse it well and then follow its use with a rewash with Simple Green before a final cleaning with Invisible Glass.
CLR contains some acids and I don’t want residual problems with anything below the windows from acid residues left to fester.