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Letter 16

Isuzu Trek Owners Infoletter #16

Editor’s note: You will notice that the contributor’s email addresses have been altered by changing the “@” to “at”. This was done because, since Al is now putting the newsletters on his website, it should keep web-crawling spammers from picking up the email addresses to add to their lists, so it is a form of protection to keep you contributors from having your addresses added to another spammer’s list.

About “hopping up” or Boosting your Trek Engine so it will pull that grade faster

An Opinion, by editor Dale:

Lots of folks have asked me or told me about increasing the power output of their Trek engine by propane injection, methane injection, etc.  Just recently, a respected friend asked me the same question. Here is what I wrote him:

I learned while still in high school that if you hop up an engine beyond its rated output, you greatly decrease the time until you get to rebuild the engine! In the case of my 41 Chevy after I installed a three carburetor manifold, it wasn’t long……only until I dragged a 51 Ford. I beat him in low gear!  Then my dad dragged me home to start a lengthy rebuild of the engine, performed by (you guessed it) yours truly. That was more than 50 years ago, and little has changed on the subject.

Boosting an engine beyond its design capability, whether you do it with propane injection or methanol injection or turbo charging beyond one atmosphere, if it increases horsepower or torque output, it stresses many parts, including but not limited to the crankshaft and its bearings, the connecting rods and their bearings, the wrist pins, the pistons, the cooling system, the lubricant (oil), the transmission, the driveshaft, the differential, the drive axles, etc.

 These stresses may or may not be more than the part(s) can take. It won’t be apparent until things start coming unglued and when they do, they often damage other parts.  When will it happen? That is the unknown. One thing is for sure though: it will happen sooner than if the engine was run properly at the ratings for which it was designed. The greater the boosting, the shorter the time until something gives. In the case of methane injection where horsepower and torque can be doubled or even quadrupled, the time until giving (money for repairs) may be shortened to milliseconds.

 So if your purpose is to create a hot rod motor home with the understanding that your resources (either money or mechanical ability or both) are going to be needed sooner than later, to affect major repairs, go for it, and enjoy getting to the top of the hill faster….for awhile.

But if you have other places you want to spend your limited budget and don’t want your motorhome down for major repairs, then use that first gear and be content with topping that steep grade at 15 mph. Lots of nice things happen at 15 mph: it is slow enough that you can relax, look around, see small animals doing their thing near the roadside, the torque converter is locked out so your tranny isn’t overheating and life is good. You aren’t really in a hurry anyway. If you are, get an airplane or a Lamborghini!  And what about the guy in the yellow Lamborghini that is behind you honking at you and flipping you off?  That is really his problem, not yours, isn’t it?  Just let it be so.

 What are my qualifications for the above opinion?  Not much, except a lifetime of managing and trying to understand engines, both in the air and on the ground. And, I wrote the book “Aircraft Systems for Pilots” that is used as the primary textbook in most of the colleges and universities that teach aviation in the English speaking world (see

Enjoy your Isuzu Trek. It is about as perfect a small motorhome as it gets, just as it is…in my opinion!

 Electrical & Battery Charging

Jim White (Jwhit2 at ) said: I did have something strange happen this winter.  I had my Trek plugged into a 15 amp 120v outlet to keep the batteries charged (Should the main switch by the door be left on or off if you want to keep the batteries charged?).  Anyway, the connector plug got wet and that tripped the GFI in the house circuit, so the batteries ran down (nothing was on that I know of in the Trek).  (I am not sure, but I think it also may have tripped the bathroom GFI in the Trek…  Should that happen?)

My solution was to wrap any extension cord connectors that are exposed to weather with Saran Wrap for at least 3-4 inches beyond the connector.  It worked like a charm, no more trouble with tripping the GFI in either place.

Editor:  Jim asked: (Should the main switch by the door be left on or off if you want to keep the batteries charged?). Here is my answer (somebody correct me if you think the following is incorrect.)

If the Trek is plugged into shore power it shouldn’t matter, because:

The switch by the door only shuts off the 12 vdc circuits in the trek, whereas the Heart Interface inverter/charger has direct access to the house batteries, so they will be charged by the charger if it is plugged in.

 If the Trek is stored (for more than a day or two) and if the Trek is parked where the sun can reach your solar panel, it will keep the batteries up, but the switch by the door must be off because, unless you have increased the output of the solar panel, it won’t keep up with the nominal load on the 12 vdc system as there are still some things ‘on’ (such as the CO detector, for example.  The switch by the door stops all 12 vdc electrical loads in the coach so that the solar charger can “keep up” and charge the batteries with its small output.  The switch by the door being off also decreases the chance of an electrical fire while the coach is unattended.

The Trek owner also said that, while the Trek was plugged into shore power with an extension cord, it rained and water got into the connection, causing  GFIs to pop open, causing the batteries to become discharged.  For clarification, the popped GFI in the house circuit (shore power to the Trek) removed power from the Trek’s charger. The GFIs in the Trek being open would not cause the charger to be unable to charge the batteries, so the fact that the GFIs in the Trek were open was incidental to the batteries becoming discharged.

 For the above discussion, I assume Jim was talking about the house batteries rather than the chassis batteries because the Heart Interface charges only the house batteries, not the chassis batteries. The solar panel charges both.

 Loose dashboard screws again

Dutch (dutch_98221 at ) writes:

One more item about the problem with screws coming loose on drivers side of dash:

I drilled out one of the pop rivets (the one just forward and below the mirror) on that vertical metal strip, drilled it through to the angle on the interior, and installed a 5/16 inch bolt, washer and nut.  I am hoping this will be a better fix as the screws kept coming loose.  On the passenger side, I could not do the same, as the mirror is located differently.

 Editor: this is an often-brought-up topic. See discussions about firewall bolts in issues 4, 6, 7, 9 and 14.

 Trek Step

Joann and John Figueras (joannf4 at )contribute:

We’ve replaced our Quickee step (’94 Trek)!  It started to get a mind of its own at the ’04 Trek rally in CO, and the tech’s advice was to get a new ‘brain’ for about $100.  I fooled with the step for months, and sometimes it worked, and sometimes it didn’t.  (I DID check the ground wire!)  Finally, after digging out the side of the driveway with the extended step and bending it more than it had been, I checked the web for prices and found a new step for about $250. We purchased the new step from RV Supply in OR—after looking at results of a Google search.  One other thing about it–the new step’s top mounting bracket is shallower than the old one, so I was able to mount the new step
farther back, so the retracted step does NOT protrude like the original.  Apparently Kwikee has many models but RV Supply carries only one–just happened to be OK.

Installation was not too bad, but removing the old one was a job.  It had been installed with carriage bolts on washers, so all they did was turn on themselves.  Finally had to cut the bolts.  Then the new step had holes in different places, so I drilled new holes in the Trek.  (Instructions said to drill new holes in the step, but the 3/4 ply was rotted around the old bolt holes and I found solid wood with the new holes.)  I added metal bars across the depth of the step for extra support and used lag bolts instead of carriage bolts.  (I suppose the ply should have been replaced, but it seems to go under the back and side walls, and I didn’t want to get into more trouble than it was worth.)

 Anti-slosh/siphon fix

Joann Figueras (joannf4 at ) solved the problem of loss of fresh water from her trek’s tank by the following fix:

I did another thing to the Trek before we left for this trip–did it because we lost about 5″ of water from our fresh water tank last year in Baja on our way to the beach.  I cut the
grey plastic pipe off the overflow fitting and screwed the fitting out.  (I had to tilt the empty tank to allow it to turn past the wood support.)  Then I installed a fitting that goes straight up and clamped 5/8″ flexible tubing onto it.  The tubing goes UP about 16″
and then back down and is connected to the remaining piece of overflow pipe.  Used some fittings to make the top of the “U” and then cut out the floor of the closet to allow my raised overflow to go up the side wall, where I fastened it to the wall.  Works well.  I
didn’t drill a hole in the top of the loop for anti-siphoning because that hasn’t been a problem for us.

 Thank you for your contributions!  Hey, everybody:  send me your Trek problems, repairs, fixes and parts sources for the next newsletter NOW, while you are thinking about it!   Thanks!   Dale