Testing a turbo diesel engine

[Snow]

Hi ya All

I'm looking to purchase a 92 Prado 3L turbo diesel. I've been told they have the same engines as the 90 series.
I know bugger all about deisel engines and want to find out what is involved with testing these engines.
How hard is it to do a compression test on these motors ? Is it just a case of pulling the injectors out and screwing in a meter.
What other test can be done to find out if the motor is going to go bang in a big way on the way home?

[ISUZUROVER]

The easiest (and one of the most important) thing to do is pull the oil breather pipe off and see if crankcase pressurisation is occuring, then pull off the pipe from the turbo to the intercooler to see how much oi is getting past the turbo seals. While you have the pipe off check for play in the turbo spindle but be gentle.

Also check what it drives like and listen for any strange noises.

Compression tests on diesels are difficult to do without specialist equipment.

[Snow]

Thanks ISUZUROVER

Good tips there. I know how to check turbos but its just a doing a compression test that gets me, never done one on a diesel before.
Any thoughts on a leak down test instead of a compression test?
I've have never done either on a diesel before but might get a specialist to run a leak down test for me if its too hard for a compression test.

[Gribble]

Thanks ISUZUROVER

Good tips there. I know how to check turbos but its just a doing a compression test that gets me, never done one on a diesel before.
Any thoughts on a leak down test instead of a compression test?
I've have never done either on a diesel before but might get a specialist to run a leak down test for me if its too hard for a compression test.

The main difference between compression and leak down is that a compression test will tell you your loosing compression, a leak down will help find where its loosing it through.

Much the same as a compression test you need the specialist fittings and guages and air valves etc. to perform one. A compression test is much simpler!

[dumbdunce]

too much noise (whistle) from the turbo can be indicative of slop in the bearings which can lead to expensive turbo repairs. look for leaks in the cooling system (get it pressure tested if you can), and look for evidence of overheating.

[dow50r]

Mate, you need special compression testers for a diseasal...i would take it to a diesel shop and have them check it over...having a service record book helps make that decision too....these motors are pretty reliable i think....another way to check would be to put it up on a dyno and see how it compares to others...might be quicker and less expensive...
Andrew

[Snow]

Thanks Guys.

I'm going to get it tested by a diesel specialist, the price of specialist equipement and my inexperience with diesels warrants this.
Just trying to decide which coarse to take, one mechanice charges $125 which includes a compression test and the other charges $155 which includes a leak down test. Both sing the praises of their test over the other and both will inspect the turbo

I've also noticed on the swivel hub/front axle it is quite damp and has leaked a few drops of oil on the ground.
Anyone know how hard these are to repair? Is there a seal which holds the oil at the end of the axle or does oil flow into the swivel hub itself?
I've never pulled apart these kind of hubs before but i'm pickin there might be a oil seal between the axle and the uni joint to hold oil in.

[bazzle]

You should probably Start a new thread for the Hub. Under Toyota tech

Bazzle

[Snow]

I've been given the good oil on swivel hubs, but thanks anyway Bazzle.