Offroad-Express

Hi there, I have a 3L 2.8 diesel turbo engine in my 91 Toyota Prado. Most times, after driving through a river, I have a few seconds or so of the motor blowing white smoke. After doing this today, shortly after my motor started to blow BLACK smoke, and shudder/miss? on throttle. (idles and behaves okish below 2000revs or so). Also for s short time when revving motor there was a slight knocking noise, but after being recovered and getting car home, can rev it to around 3000 and no knock, just very underpowered and shuddering and black smoke. People that helped me out, said its probably a bent Con Rod from water getting into the motor, but ive read online and others say may be injector? What is the probable cause of this, and what avenues do I need to take to diagnose/repair.

Thanks

Has it got a snorkel and is it sealed properly?, if not then the air intake should be inside the drivers guard.....unless its been changed when the 2.8 went in...

Have you checked the air filter for water?

Did you go into deep water or was it like it when you got it?, if its sucked a bit of water now or previously then its farked.... ask Nstacey or Skid .....theyve just had to rebuild/replace their motors....

Diesel engines do not handle two things

1) Getting hot
2) Swallowing water

When you see white smoke this shows swallowing water, a teaspoon of water is enough to kill a diesel.

You can do two things to test the engine get a leak down test to prove the head and rings are okay and second get a compression test to prove compression in the cylinders is consistent.

I suspect a bent rod and you could drain and pull the oil pan and look up the bores to see if one is bent.

Repair can cost a lot good luck.

UPDATE :

Well this weekend, I have taken the time to remove the Head and Sump to get the pistons and conrods out. Visual inpection tells me that all the conrods are straight and in good shape. All the rings look to be complete, there is no scoring on the bores, there is not any excess play in the bearings, there are no cracks on the head or block (that are visible) and everyhting looks as it should be. Is there anything else I can look for that may be causing this lack of power and intermittant knock, and smoke from exhaust. The headgasket looks old, but no visible signs of cracks etc.

Cheers for the replies

A visual inspection is good to start with but will not always show up a cracked head so that need to be crack tested and warp tested.
The bores need to have taper and out of round measured as do the bearings

While it is in pieces it is easy to do.

There is a possibility that water has allowed the timing belt to slip a couple of teeth affecting Fuel and valve timing which would account for a lack of power.

How long since you changed your fuel filter ? It may be blocked starving the motor and making it run rough.

While it is in bits do proper checks and it will give you peace of mind long term

Cheers Richard

Hi, the head and conrods are going to the engine recondition to be checked, but just wondering, so it is in fact possible for the water to cause the belt to jump? If the diesel and valves are out of time, would this cause the lack of power, and the knock could be diesel knock by the pump being out of time? Thanks

..

The diesel pump is gear driven off the crank I thought, it is possible the timing belt moved a couple of teeth. Did you do a compression test or a leak down test before pulling the engine to pieces, those would have told you the area to look.

EG Leakdown suggests rings or cracked head
Compression suggests bent #4 or head gasket (if it was low) and you look at #4 or that area.

You may be lucky and just have blown out a little of the head gasket, if you change head gasket you re-time the head and pump anyway