Heat(ed) Exchang(er)

Earlier in this blog I sang the praises of our Entec 4200 generator. I’m not singing now. While it does a good job of providing AC power, its maintenance challenges are ugly.

Whoever designed this must have imagined it would only be installed where the user could walk 360 degrees around it at table height. Whoever designed the acoustic enclosure apparently gave no attention to what would be blocked from routine access. It is ridiculous to have to uninstall a piece of machinery like a diesel genset, just to perform routine maintenance. The oil and coolant and the air filter can be changed and the valves adjusted with ease. From there, it goes over a cliff.

When the water pump self-destructed from bad design (my engineering opinion), it took hours to get the damaged parts off the engine. I had to grind a wrench down to where it would fit on the necessary bolts and work blind. (Actually, I used my webcam on a long cable  and worked reversed.) [Then of course there was the additional $300+ I had to spend to retrofit the genset with the kind of pump it should have had in the first place.]

When the starter motor failed (at only ~850 hours), the genset had to be unbolted from its mounts and pulled out of the acoustic enclosure just to be able to fish the old starter out and the new one in as if they were complexly carved puzzle pieces. Seating the starter shaft had to be done blind.

Now as part of routine maintenance, the heat exchanger zinc must be checked/replaced (I’ve done it once before — I can’t remember how.) This time it took a day to get the job half done. I had to cut a 19mm socket down to 1/8 inch of grip to be able to turn the zinc holder bolt. Why? Because the heat exchanger zinc port had been positioned with a fraction of an inch of clearance from an immoveable hose, and the bolt faces were too thin to accept an awkwardly angled (because of acoustic enclosure interference) box wrench without slipping and rounding the faces. There was room for the heat exchanger to have been positioned inches away.

Unfortunately, the zinc holder bolt sheared off and half is left in the heat exchanger zinc port. It’s going to be interesting to get it out. At least a day, I’m thinking. [The only good news is there was zinc left.]

Then there is the guidance to check the heat exchanger tubes and rod them out if necessary. One can barely remove the end caps on the heat exchanger with it in place in the back of the acoustic enclosure With one inch clearance at the ends, there is no way a rod is being fed into any tube. The heat exchanger can’t be removed without completely uninstalling the genset. It may end up that I have to install a new heat exchanger outside the acoustic enclosure — bypassing the one that lurks under the actual generator unit.

I will say this, when the water pump debacle ensued, I got good phone guidance on how to get the d**med thing off the engine. And when the genset wouldn’t start last winter, I got good (if counter-intuitive) explanations of why valve adjustment was necessary to make that happen. But… in the midst of all this, the Entec owner has sold the company and access to useful phone help has evaporated.

When trying to hand start the genset on one of the 100 degree days after the starter failed (it was 135° under the cockpit floor where I was attempting this), I was instructed “not to be afraid” of it and “put my weight” into it. When I pointed out I was sitting under the cockpit floor without head room at a 45 degree angle to the genset in a drenching sweat. I got ~ “well then you probably aren’t going to be able to get it started.”

And the jury is out on the new owners. When the new starter motor arrived it came in a box that said ~”Return for Core Credit.” So I called. The response was, “No credit on those starters, it was just the first box we grabbed.”

The Entec genset has turned from reliable benevolent genie to a dyspeptic troll. The good thing is the solar panels are so effective we only need the monster for air conditioning, and we are trying hard not to be in places where that is necessary.

I really can’t recommend these units to anyone who won’t be able to access them from 360 degrees, while standing up. They also must be installed with enough hose and cable slack the 175# genset can be pulled substantially from the acoustic enclosure for routine maintenance — not just the inch I can manage without disconnecting several hoses — by feel.

Part of this is we now live on the boat and usage of all equipment has increased, but most of it is what I consider bad design for maintainability*.

Caveat Emptor**

*This is unwelcome deja vu. In the late ’70s, I was the chief engineer for the program to bring design for maintainability and operational reliability to the diesel flightline handling and storage area equipment used with air ordnance. This assignment came about because I had been a Munitions Maintenance Officer and had seen first hand how bad it can be. This genset, from a maintainability perceptive, is every bit as bad. Nothing which requires routine maintenance should ever require more than removing an access plate to reach and normal tools to service.

**Shame on me for not paying more attention to these issues when the boat was being built.

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