Thread: How to kill your Defender in 8 months

You may have read my post recently about testing a motor driven air compressor on the 300Tdi Defender. http://www.aulro.com/afvb/1253348-post1.html

But just as I was about to head out of the driveway the car broke down http://www.aulro.com/afvb/1258352-post24.html

Anyone want to guess what the problem was?

I made a call to Stuart from Rovacraft who suggested that the timing belt might have slipped one tooth. I was confident that it shouldn't be the belt as it had been replaced only 40,000km ago and it was running normally up until this point. Stuart asked "who fitted it?" to which I sheepishly replied "I did". His comment "there you go...with eyes rolling". Now I admit fitting a timing belt to a 300Tdi is not my normal day job but I fitted this one up after reading everything I could find on the timing belt. My truck was the first one I had done and have done three others since, BrendanB's two Defenders and Michael2's so felt sure it had been done right....but the doubt had set in maybe I didn't tighten the tensioner properly thus causing it to slip.

Over the weekend I couldn't stop thinking about what it could be. It soon became the common discussion point around the camp fire. We all eventually concluded that it could only be a timing/timing belt problem.

After the the 5hr return trip from Big desert Steve (Madana) and I started to look over the truck mind you this was Sunday night just after 7pm. (SWMBO was none too happy!).

Now without the high pressure situation of a few nights ago we could diagnose the problem methodically. Fuel is ok, no water, power to injector pump, fuel coming from injector harness etc. The first thing I did notice though was a few steel ball bearings under the car. "Any idea where these could come from?" I said to Steve. "No idea" was his reply. I decided it wasn't related and put it down to having two small boys that like throwing things around.

The rocker cover came off next and my worst fears were realised. Two broken rockers and two severely bent push rods. Interference motor and timing belt failure immediately ran through my head.

It was getting late and cold but I couldn't stop there. I had to know what caused the timing failure, especially with my mechanical skills/reputation on the line. Also because this is my daily driver I wanted to know what needed to be purchased on Monday to get it back on the road quicker.

We started stripping down the motor, draining the radiator and motor of fluids, removing shrouds and all belts to get access to the the front timing cover so it could be removed.

And this is what we found on opening it.





The idler bearing had completely collapsed! All the ball bearings were dropping out of the wading plug hole. Which is what I had initially found on the driveway.

Now this was not what I was expecting at all but it did not take me long to realise what caused this catastrophic failure, in fact Stuarts words from 8 months ago rang through my head hauntingly. "you will kill your motor going through bog holes like that! I just didn't think you were the type of person to do that sort of thing. Don't you want to keep your Defender? That Toolangi mud is so abrasive, its like grinding paste......it gets in everywhere"

And this is what he was referring to.



Now to put this into perspective. I normally am the one to bypass holes like this. But on this occasion I had fitted up my muddies and just installed the Tigerz11 winch. It needed to be tested so was an important experiment!

Wading plugs were in, snatch strap attached and after checking the water depth thought hey I might just get through. Maybe not the best judgement call but I really wanted to see what I could do.



But I got stuck 3/4's of the way through and it took a fair bit on snatching and winching to get me out because of the awkward track and slippery conditions. All told I was probably in the water for 10 minutes with the motor running.



The winch worked a treat and I now know what my muddies are not capable of! When I removed the wading plugs the following day a handful of water came out but at the time I did not think much of it. In hindsight I would say its worth removing them immediately after big water crossings just to make sure you haven't sucked in a lot of water, even better a breather on the timing cover would probably prevent this in the first place. FYI the diff oil was changed recently and was clean with no apparent water/mud ingress so the diff breathers worked.

We called it a night around 12:30am early Monday morning as I had work the next day. I checked the weather for the coming days and week and it was not looking good. Rain was on the way so we better get onto it quickly as I can only work on the truck in my outdoor garage!

I built up a list of items I would need.

1 x Timing kit
2 x Push rods
2 x Rockers
1 x Head gasket (260,000km on the clock)
1 x Head bolt set (didn't know bolt history)
1 x Exhaust gasket (oil leaking down side of motor)

On further investigation the next night we found two more slightly bent push rods. This prompted the decision to change all the push rods and rockers. The crank pulley was extremely worn and the injector pump and cam pulley also slightly worn so all were replaced.

Once the head was off we could see two clean valve impressions in the disel particulate on the top of the number 1 and 4 piston. The pistons had no cracks or chips which was a relief.

I was just going to replace the valve stem seals but Stuart recommended getting the head checked and reconditioned because you "just don't know". I am glad I listened to him as the reconditioners found that one valve was slightly bent and one valve stem guide worn. It was decided to replace all valves just to be safe. $600 dollars later it came back looking better than new! So essentially I have half a new motor.



Cylinder head going on.



I replaced the cam shaft seal, crank pulley seal and o'ring and all the timing gears as well as reset all the timings - they were really out, not just a tooth or two!



New push rods and rockers fitted up. Auxilliary equipment all going back on.

While I was at it I replaced the water reservoir, power steering pump due to some end play in the shaft, fan belt, silicon turbo hoses, water pump & p-gasket, tidied electrical cables, cleaned and flushed the radiator and intercooler. Still to do is a breather line for the front timing cover.

Well after too many cold late nights the car is alive! Think of us working on all those freezing cold foggy nights Melbourne has been experiencing, I had to have thermals on, just so we could get it back on the road before the coming rain which came down heavily the very next day!

This repair would not have been possible without the help of Steve who has been at my house on most of the nights I worked on it! Thursday night till 3:00am....yawn because I really needed it going the next day to drop kids off and get to work. Thanks Steve this was very much appreciated. Also BrendanB and Michael2 lent a hand when able and this was also much appreciated. And of course I must thank Stuart who has helped with his expert knowledge of all things Land Rover and sourcing parts on short notice. I know he will never let me live it down but thanks you have been a great help.

I hope this story and expensive repair helps you avoid the same mistake I made.

So now that I am back on the road I will be heading back to the desert to give the motor driven air compressor a good workout and will post these results up soon.

Originally Posted by cewilson

I'm curious as I've spent a lifetime playing in mud holes like that. I've had to rebuild alternators, starter motors, radiators etc. But never have I had damage like that!

Was there any other mitigating factors in the damage? It seems quite a lot of damage from mud unless there was something else wrong.

I didn't believe that there was much difference between the 200tDi and the 300tDi?

Toolangi mud! Is the majority of the mitigating circumstances. It sticks to anything almost like glue and stains everything that touches it. When dry it is an extremely fine powder.

The other one would be that I had stuck on the timing cover with gasket former so it really sealed well. When I plunged into the mud it sucked in the water/mud.

And thirdly leaving the wading plug in till the following day with water/mud trapped inside made it get lapped around the cover. A fine mist seemed to completely cover the inside of the timing cover.

It is a real pain to clean. I am still cleaning off the mud! The radiator and intercooler had to be soaked overnight to help clear it. And this was after hitting it at the car wash.