Low KM engine failures

[Footy Shorts Shane]

I've seen a few engines at the drags fail with very little "miles" on 'em.

Always a good look with the rods punching windows into the cylinder block and a sump full o' lumps.

Seen that once or twice too.

Shane.

[Footy Shorts Shane]

Young bloke next door to work had a Mazda 7 something junk a turbo real early. Whilst searching for another turbo he found one that was only 35k and junked a turbo and engine.

Saw a Nissan Xtrail, (I think that's what it was) spin a bearing at a little over 100k. Replaced crank, rod and bearings, only to window the block 20k later.

But all in all, when I started as an Engine Reconditioner 20+ years ago, we were reco'ing about 8-10 cylinder heads per day for the local workshops. Only 1 dealership, the rest were small shops. Most workshops today would be lucky to R&R a cylinder head a month, with a lot refusing to do engine work. Engine Reconditioning shops are scarce now and the ones who don't specialise in heavy diesel, are mostly struggling. It's a dying trade due to the modern engine.

As for no locating tangs in modern engines, correct. They don't stop the bearing from spining in the rod. The cap crush on the bearing does that. The tangs primary purpose (as far as I believe) was to make the installation idiot proof for the unskilled worker sitting bearings into rods and blocks, shift after shift after shift. No need to idiot proof the engine assembly line now, just the guy who programmes the robot.

Shane.

[westvic]

Funny that - the Jackaroo was the first of the real intro to high performance diesels.  They were a sweet powerplant but as you say, turned turtle when given a sniff of the wrong grade of oil.

From memory they also had a second oil filter that many mechanics didnt know about, hence often didnt get changed, which also lead to turtlish behavior.

Having said that the previous version 3.1l had a much better reputation and the 2.8l before that was almost impossible to kill. Natural progression though, if you follow this thread, later models = more power = more stress on engines = greater risk = higher chance of failure. However, this is still just playing the odds. Older engines still go BANG sometimes and newer engines can still last for ages.

Play the odds and do the maintenance. Still not guarenteed but doing regular service/maintenance is cheap insurance in the long run.

Having driven older diesels and newer diesels i do know which is nicer to drive though 

[Bird]

There's a D4D Prado currently having an engine rebuild in Kununurra, 100,000 klms $18K.

Sure it aint a ZD30?

[Matto]

Low KM engine failures are my speciality.

Dad had a pair of Ford Couriers chew their motors at about 35,000kms.

I was driving the father-in-law's Courier one day when it's motor let go at just on 30k kms.

Last week, a Mazda Bravo in Dad's fleet let it's head go in a big way, just on 40k kms on that one.

The reason in all the above cases was short trips, and an easy life. The vehicles were all low-milage, had been used predominately for short, around-town trips, and hadn't been used to tow or cart heavy loads. Mechanic's advice for modern small-capacity turbo-diesels was not to use them for this sort of driving - buy a petrol instead. They said that heat-cycling the motors with lots of short trips leads to the alloy head failures, and babying them in general does more damage than using them hard, putting them under load and doing long trips. Mechanic says they have been seeing steadily more and more TD dual cab utes coming in with blown motors as they've become more popular as "everything cars", vs rattly, old, slow work trucks.

That said, the single-cab TD Hilux ute that has been loaded right up and used to tow a heavy trailer is now on it's third clutch (about 30k kms total) and is in desperate need of new suspension. So while it's motor might be OK, the rest of it is decidedly sad. I suspect this is one of those areas where "they don't make 'em like they used to" applies.

Cheers,
Matto
(Who should not be let near a car that you like - it seems I have the touch of death for TD cars and utes)

[fishfinder]

Sure it aint a ZD30?

In a Prado ?

[shanegtr]

I work in a reliability field for industry, so I feel reasonbly qualified to comment on machinary failure as trying to avoid failures is my job Apart from general design failures that causes the same failure across multiple units, failures can and do occur randomly. This can be for a varity of reasons, manufacturing issues, assembly problems etc...... The more components you have the more chance of failure. The highest chances of machine failure occurs during commissioning (brand new) and after rebuilds (infant mortality), and then again as the machine nears the end of its life (weasr out failures). Everything inbetween is often subjeted to random failures. Google "bathtub curve" and you'll find a heap of info. Generally speaking I find a lot of failures occur after maint has been carried out and machines fail because something was over looked/not done correctly. I think there would be very few engines in the automotive world that would truly reach their end of life wear out failure point.