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Hi All,

Well, during my long winded rebuild, after a long wait of farting around with panels etc i've moved onto mechanicals and have the engine, trans, transfer case, radiator, front diff, front springs, all hoses and A.C system out.  I won't go through what i'm fixing/replacing/rebuilding as i'll do that in a report at the end.  What i'm wondering for the moment is with the engine out (and it's a lot easier to access) what things should i check for maintenance?  For example, i went to take the water pump off because i need to replace the gasket behind it and also thought it would be worth checking the condition considering #57 has done over 500,000km and a bolt was rusted in.  I rounded the bolt head and had to weld another bolt on top to get it out, the original bolt then decided to break in the housing...  I'm not too worried because i would much rather this happen here where it's easy to fix!  I'd really like to get to any other common/difficult-to-fix  faults/points-of-failure now before i get the engine back in.  It will be out for atleast a couple of weeks as i'm doing a fair bit while everything is out...  Any thoughts or advice?

Cheers,

Alister

Alister, I recently had to take off the injector pump to fix a leak which meant removing the hydraulic pump first to get at the lower fixing nut.

While you've got access to it, I suggest changing the top bolt on the hydraulic pump with a socket head bolt so it's easier to remove from the rear if/when the time comes.

Another suggestion is to replace the small water hoses on the LHS of the engine to and from the oil cooler. If they split they are difficult to get at. You can get a cheap Commodore heater hose with all the bends already on it and cut it up as required.

Also you could change the fuel line from the lift pump to the fuel filter which is prone to leaking. It goes behind the engine and the lift pump end is difficult to access.

Alister I have  found over the years as an owner driver that any major as you are doing it best to replace any/all flexible hoses you can find apart from the age condition its so much easier with the vehicle dismantled and it gives peace of mind when venturing off into the wide blue yonder.

Cheers Dave

Alister, yes, what Dave said. But also you could usefully replace the solid water pipe from the thermostat housing to the oil cooler with a flexible heater hose.

This pipe severely gets in the way of any work around the injector pump since you can't move it out of the way, and if you remove it, I found the top threaded union extremely difficult to reconnect.

A hose connection at the top would make things simpler and I wish I had done it as part of my injector pump reseal.

Thanks David's!

Thanks for the advice!

I actually pulled the hydraulic pump off to see about getting a bigger or dual replacement to run the winch as well and noticed how hard it was to get that bolt out even with the engine out!  Must have been a nightmare in the engine bay!  Even getting to the bottom fuel pump bolt would have been hard!  On that note, i'm just about to fix that fuel leak from the throttle shaft myself, have you found another one?  Would it be better getting it overhauled?

On the note of the metal tube running from the thermostat housing to the oil cooler, i think i'll leave it as is because before you replied i'd already gotten a new one made up and although that thought had crossed my mind, i'd be worried about rubbing points etc with a hose dangling there...

Also wondering if anyone can help here, when i got the oka there was no glycol in the cooling system and although i changed that straight away i've noticed a lot of scaley rust inside the cooling system...  Is this a major problem with the perk?  Also, how would i flush it out, is there a 'flushing fluid' you can use?  And, how do i tell if the waterpump is worn do i press the impeller out somehow or press the gear off and then the impeller and shaft out of the housing?

Cheers all,

Alister

alister, go to your local coles or woolies & buy a bag or 2of  'electric soda' (in the laundry isle) mix in a 10-25 tlr bucket of warm water untill disolved, then pour into radiator. i drive around for a day or so then drop lowest hose & drain & rinse/flush repeatedly 3-4 times.i have done this on all 4wd's i've owned & has worked well.(although haven't done to 420 yet)

P.S. works even better if you remove thermostat first. but dont forget to replace when flushed.

Alister I've replaced the throttle shaft seal a couple of times. It can be done in situ and is not too difficult, and if there's nothing esle wrong with the pump, there's no need to remove it, especially as you already have the engine out.

See my original blog entry. There's also a bit in my blog on removing the pump.