Everyone Should Rebuild An Engine

Rob Bell

Issue 19, February 2019

While we’re teaching our kids how to code, I think they should also be taught to rebuild an engine.

Actually, I take that back... EVERYONE should learn how to rebuild an engine. While arguably the days of the internal combustion engine are limited, they remain a shining example of human engineering.

Yes, they’re inefficient. Sure, they’re noisy. However, they represent a stellar opportunity for understanding of mechanical engineering and gaining an appreciation for industrial design. It’s something many people won’t appreciate when turning the key to start their car each morning, or pulling the starter cord on their lawn mower on the weekend.

While they have become infinitely more complex in recent years, with complex computer hardware and software monitoring just about everything possible, they’re still relatively simple beasts at their core. Seeing just how an engine does its thing can provide valuable insight and perspective when machinery or technology fails to perform as expected.

I recently had the experience of rebuilding a marine transmission. As someone who grew up around cars and started my working life as a mechanic, this wasn’t a huge leap in terms of technical ability.

However, one thing had always bothered me about this transmission - I didn’t know what was inside. Sure, I had a basic understanding of what it was doing, having worked on vehicle transmissions a number of times, but I didn’t truly appreciate how it did what it did.

So naturally, when it required an overhaul I jumped at the chance to understand this cast iron beast better.

Most marine transmissions are fairly straightforward, with a forward and reverse gear, as well as neutral. This particular design uses an internal hydraulic pump to create pressure on clutch plates, to engage forward or reverse gear, or simply recirculate the hydraulic fluid when in idle. I won’t go into the specifics further, because it’s not terribly relevant. However, I now have a full understanding of what’s going on inside the unit.

While I hadn’t intentionally undertaken this overhaul task as a learning experience, as I began the task of removing the first bolts to discover the secrets inside, I couldn’t help but notice the knowledge I was gaining along the way. Every disassembly of what appeared to be a single unit revealed more working parts. In contrast, what appeared to be complex parts were, in fact, surprisingly simple.

What was most interesting, however, was that I hadn’t specifically set out to understand the transmission at all. I merely had a goal; remove the rust, replace the serviceable components, and reassemble with fingers crossed it still worked once reassembled. If it went back together with the serviceable items replaced, and still worked at the end of the day, I was going to be a very happy camper.

However, what I received was a thorough education on how this transmission does its job.

If there are mechanical troubles down the road, where it won’t engage (or disengage), or it slips under load, I can almost certainly diagnose the broad issue without even tearing it down again. While this level of knowledge isn’t entirely critical, having a more in-depth understanding means less mystery when something goes wrong.


We all know that waste, in particular, e-waste, is a major challenge of the 21st century. By creating or increasing the understanding of how things work, we can almost automatically reduce e-waste. Let’s think about this further.

Can you imagine if people thought that cars were useless when the engine broke down? This seems silly, but many people consider a computer, phone, or other pieces of technology to be total trash when they fail. While indeed, modern electronics is less geared towards repair than a car, many options still exist for repair in just about all circumstances.

This opportunity for repair also extends to (arguably) less complex electronics such as your coffee machine and such.

While commercial repair isn’t always viable (since the hourly rate of a technician may be more than the cost of a cheap coffee machine), placing greater emphasis on repair (or at least diagnostics to confirm if repair is viable) is an important step to ensuring equipment is indeed ‘end of life’ or unserviceable. If we don’t, the broken TV, for instance, is put out to the kerbside cleanup with a brand new replacement already sitting in its place.

I think it’s safe to say we’ll never see a return to highly serviceable consumer electronics, but due diligence when it comes to repairability will help keep unnecessary waste to a minimum.

So let’s educate. The more we educate, the better we can handle the challenges that face our increasing adoption of technology.