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Discussion Starter · #1 ·
My cousin's 10yo Patrol's engine blew up on the Hume Highway a few months ago. Uphill at 110km/h, puff of white smoke, no power, side of the road, mobile phone, NRMA, tow, overnight in bad motel, towed home, rebuild, huge expense etc.
But being the (remarkable) scientist aeronautical engineer CAD/CAM metal machinist electrician with an industrial workshop that he is, he's determined quite a lot about what caused his engine to self-destruct and in fact he's built and installed monitoring which make it very unlikely that he'll suffer the same event again.

I'm just wondering if engine failures around the 10 year mark are common and whether he'd find other owners interested in a kit which they could install to avoid the $10k cost he suffered.

I'm obviously the MBA in the family but I think what he's learned and prototyped is pretty impressive so I'm inspired to do this little bit of market research and if it seems there's interest, encourage him to develop it further - not to get rich but mainly to prevent disasters and stranded families.

I'll quickly describe the issue but forgive me for not being able to explain it well: (If there's interest I'm sure Bill will explain it in proper detail.)

It seems that every time the engine stops, back pressure from the turbo sends a pulse of dirty air back up to the airflow sensor which over time (start/stop cycles, 10 years, 100,000km) becomes dysfunctional. The engine management computer does various things to work with the issue but in most cases ends up running the turbo too fast (or something) and raising the temperature in particular cylinders (the rear two are the most vulnerable) and eventually the circumstance are such that superheated gasflow burns a hole in a piston. Game over.

Now common attempts to measure temperature at the turbo are misguided because the harder the engine works, the faster the turbo spins and the colder the measurement at the turbo so drivers with such guages would actually see lower readings when most at risk.
And the engine warning lamp may help but can be impacted by after market chips or there were such complications in Bill's case.
So what Bill's done is...
- source gas flow probes able to handle the high temps in the exhaust manifold
- determined how to machine the manifold for their installation for each cylinder
- worked out how to wire these so the wiring won't melt
- sourced appropriate meters guages to display the information
- worked out the danger temperature range
- created an alert light to warn the driver of the risk of operating beyong the present workload

He and I just drove from Canberra to Melbourne and back via Cooma and observed the system's operation in various situations. For the driver you have a fantastic view of the rising and falling cylinder temps and in just one or two situations can see when to back off and prevent the temps from going too high.

The way Bill imagines, a kit would encompass an exhaust manifold exchange with the probes in there, a mini loom for the wiring, the guages, warning light, mounting hardware and instructions for a mechanic to install. Maybe it would be a $700 kit? Really unsure - the main thing is that the buyer would pay a refundable deposit so Bill could be sure to get their (replaced) exhaust manifold. Maybe he'd hold a half dozen manifolds ready to ship.

Of course Bill's had the miserable experience and dreadful costs to appreciate the value of the monitoring, so I don't know if other un-scarred owners will recognise this as a necessary install. From what we've learned this kind of monitoring is essential to overcome a systemic weakness in this engine design. (Bill had diagnostic and install assistance from a diesel 4x4 mechanic mate who had seen a few.)

Please tell me what you think.

Admins if this message should be in technical or vendors please move it - I'm not sure where it would be best posted but I am hopeful of broad readership.

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