[andref]

Hi Folks

I have recently picked up a nice Gen3 SWB that was rather sickly. It was suffering from a serious miss and showed signs of excess crankcase compression. The car has done a decent mileage at 340k so I was not expecting to be able to save the engine. This was basically going to be a fun project vehicle.

However...

Once the engine was apart we found a small crack/hole in the top of one of the pistons.

Piston hole

The rest of the engine is in incredible condition. So now the conundrum is whether to fix the engine and leave it as is or continue along the project vehicle route. Of course these things are never simple since "while you are there" you might as well do all the bearings, chain, maybe the liners etc etc.

Anyway, back to the question. Does anyone have a theory as to the cause of the cracked piston? Our current conventional wisdom seems to point towards a faulty injector, but I can't see how this would cause localised heating to damage a piston. I would be grateful to anyone that could explain this to me. Also, do you folks think an EGT would have caught this?

Lastly, if anyone knows of a decent condition 3.2 DiD going please let me know. It would be worth checking against the cost of the potential rebuild just to be sure.

Thanks
Andre

[CATS]

Andre

First post and already a valuable photo contribution!! Thanks

Not many 3.2 Did around as they tend to last a long time, unless you can get one from a rolled vehicle. Just be sure you get the one before the Common Rail injection as your ECU will differ a lot and wont be useable in your case. Price would be in the R35000 - R45000 region I would guess.

I would agree that a stuffed injector was the cause and would hope that an EGT meter would have assisted in catching this, or even just a constant measure of fuel consumption figures as a stuffed injector would probably have led to increased consumption due to inefficient power delivery. Off course pump settings could also be to blame.

I would personally fit new pistons and injectors and have the pump checked and let it run for a while to see what it does.

By the way, if it sounds in any way like I know anything about diesel engines then please be aware that I know very little and the above is the sum total of my knowledge I would say

Please keep us updated on the way you go.

CATS

[RoelfleRoux]

Andref,

Welcome here.

Yip, my money is also on a faulty injector over fueling that cylinder.

[Lock]

Hi Andre

I had a similar problem caused by a “pinched” injector pipe. Before going for a replacement motor, have a look at Ernies V8 conversion project. Seems to be running half the price of a replacement motor. https://www.pajeroclub.co.za/forum/view ... ilit=lexus

[andref]

Hi Folks

Thanks for the warm welcome! Much appreciated.

Got the report back from the engineering folks today. Looks like the number 4 bore is also a little damaged, too much to hone out, so we are looking at a new set of liners. Crank is good, but not excellent so recommendation there is to go 10 tho'. Rest of the engine is amazing condition.

Thanks for the link @Lock, I've been watching this one with great interest as this was the original plan when I bought the car.

At this point I'm considering rebuilding the DiD and selling it complete then doing a (hardcore fans avert your eyes here ) Lexus conversion. It seems a shame to leave such a good engine in bits due to one little holed piston.

The fuel consumption comparison of a 4.0l V8 would be very interesting compared to my current 3.5l LWB which can make my eyes water at times.

I'll post up once the sums have been done and the decision made.

Andre

[andrew.ashton]

Hi @Lock,

I am still trying to get my head around diesels as opposed to petrol engines, so please excuse my ignorance.

I can understand how a lean burn in a petrol engine could hole a piston. How does that work with a diesel - I thought it was only over-fuelling that could cause heat damage in a diesel?

[andref]

Right-oh folks, sums are done and decision is made.

I'm doing both... Ok, let me explain. Since I have already incurred costs to remove and strip the engine I am going to carry on and fix it. It will then be put up for sale. It's getting a full rebuild, new liners, new pistons, new bearings etc. If anyone needs a 3.2 DiD please let me know.

The engine swap (as @Lock mentioned) comes in cheaper and suites the "project car" nature for which the shorty was bought originally. It's a manual which makes thinks a little easier. Luckily the guys I am working with know the Lexus engines and conversions in general well. I'll start a separate thread on the conversion with plenty of pictures

Thanks for all the feedback so far.

Andre

[Lock]

@Andre Might have gotten the "Mushroom" answer, but apparently the diesel cools the combustion chamber as it is injected...

[Jakes]

Hi Andre

I had a similar problem caused by a “pinched” injector pipe. Before going for a replacement motor, have a look at Ernies V8 conversion project. Seems to be running half the price of a replacement motor. https://www.pajeroclub.co.za/forum/view ... ilit=lexus

If a pinched injector pipe caused the problem did the engine run normal or did it have a miss, Did it have any warning signs that something is wrong, What caused the pinch on the injetor pipe, Is there a way to check and prevent a failaire like this.

[andref]

Ok, folks. Change in plan. Took the injectors and pump to the guys that quoted to work on them to be told "Oh, it's one of those, sorry no can do" Sigh...

Anyrate, new quote ranges from 5k to 25k! Since that is a rather large scale I don't really want to take a chance. Hence I will not be rebuilding the DiD, but selling it as parts.

I'll put the major bits up in the For Sale section.

On the bright side, we collected the V8 this morning. Plan is to have the vehicle running in around 3 weeks.