Coolant leak - possible malfunctioning water pump

Hi all,

I have a 1994 SC van with a 3.0L turbo diesel 1KZ-TE motor.

The last day or so, I noticed that the coolant level in the overflow tank wasn't returning back to the mark, so today I removed the radiator cap and saw there was no coolant there. I then topped up with fresh coolant and about 3 litres was required, much to my horror  I had a look for any obvious leaks but couldn't find any. I drove home and immediately put the van up on the ramps.

I had a thorough look with a torch, both from above the engine and below. I could see a line of drips along the driveway, so I knew there was a leak somewhere. There were a couple of half dried drips underneath, one on the front axle, a couple on some hoses and another on the housing next to the belts (see pic)



I could not see any fresh drops at all, so I turned the motor on. I had another look underneath, nothing.
I then turned on the front heater and looked again, nothing.
I then turned the front heater off and put the back one on and checked, nothing.
I then switched the back heater and motor off and had another look, nothing.

I was about to give up looking when a few drops of VERY warm coolant hit the top of my head  , at last I could see where it was coming from (designated by the arrow in the pic which shows a drop of coolant about to fall).
By the way, front of van is at the bottom of the pic with rear at the top. Not easy to get an in-focus photo as there wasn't much room to get within the focus range of the camera as well as light up the area of interest with the flash.

A closeup (taken before the source of the drops was discovered)



I rang up my mechanic and told him what I had done. He said by the sound of it, the water pump was on its way out. If it's the original, then it would be 19 years old, so it's probably had a fairly good run.

He said that I would need to remove the fan and loosen the flange behind which sits the water pump and look for any leaks at the base of the pump.

Has anyone done this before and is it easy to do? I'm not that mechanically minded and while I'm pretty pleased with myself for the bits and pieces I have been able to do, I feel this one may be a bit beyond me   (Mechanic is unavailable for the time being)

Does anyone know if a water pump from a Prado with the 1KZ-TE engine is the same as that for our Hiace vans? Or is it the same as that from an Australian Hiace? Or are they unique to our vans?  

If the water pump turns out not to be the source of the leak, will check thermostat area to rule that out.

Although it's probably expensive, I am hoping that it is the water pump as at least I know what the cause of the leak is and where to go next.

How easy is it to replace the water pump?

Any thoughts/ ideas/experiences welcome.

I think I may have to invest in some sort of temperature monitoring device as this experience has given me a bit of a scare  

regards,

Werner

Today my van was back on the road, so far so good. With a few phone calls to my mechanic to query a few things, I managed to take out the water pump and put the new one back in, saving myself some $$$ in labour costs.

Here's the procedure I used to get to the water pump. Hopefully it will be of some use to someone. I'm not sure on the location of some of the bolts for the seat etc for Left hand drive vehicles.

The order in which get to the water pump is as follows (hopefully all the bolt sizes are correct as I'm working from memory!)

1)  Drain coolant by loosening tap at bottom of main radiator. Don't know where drain plug for engine block is, so coolant wasn't drained from there. Bit less messy I guess if you can drain the coolant from the block.

2)  Undo 3 screws holding trim along wheel arch and remove trim. Remove the seat by undoing 4 x 14mm bolts plus 1 x 14mm bolt behind the handbrake setup. Unclip the power cable for the seat (if your van has electric seat) and remove the seat. You may need to move the seat backward or forward to gain access to the relevant bolts.

3)  Undo 7 x 12mm bolts holding down the engine cover and lift engine cover out of the way after unclipping the wire in front of the handbrake setup. I left the handbrake setup on there.

4)  Undo 1 x 10 or 12mm bolt holding plastic shroud above fan. This is located approx halfway down the radiator on the drivers side.

5)  undo 4 x 12mm nuts holding the fan in place. You have to somehow try and stop the pulley from turning. I can't remember exactly what I did, but I think someone mentioned pushing down on the belts works. Remove the fan.

6)  Loosen the nut on the aircon pulley. Then back off the adjusting bolt for the aircon pulley until the belt is loose enough to remove. Take note which way the belt was facing.

7)  Loosen the 12mm bolt/nut (can't remember which it was) located below and to the side of the adjusting bolt for the alternator. Loosen the pivot bolt for the alternator. I wasted a lot of time trying to work out why the belts running through the alternator pulleys wouldn't loosen. Eventually I found the pivot bolt after checking out the workshiop manual which didn't give any info really and also the forum. I stumbled across a reference to the pivot bolt for the alternator. In my van it's a 14mm bolt head located next to the belts on the "inner" side of the alternator.

Remove the 2 belts after taking note which way they face. The pulley wheel which sits behind the fan should also come off now.

9) Undo the 5 bolts and 1 nut holding the water pump in place. Try and wiggle the pump to loosen it. If this doesn't work, then a gentle tap with a hammer should do the trick. There may be some residual coolant flowing out at this stage. I had put an old sheet covering the crankshaft pulley wheel in place. I also put a tarp and another old sheet underneath to try and capture any stray coolant escaping.

10)  Remove the old gasket. If it doesn't easily come off, use something like a Stanley knife to carefully prise it off.

11)  Clean up the surface of the water pump cover and surrounding area.. (I didn't end up removing the water pump cover).

12)  Put new gasket onto new water pump. My mechanic suggested to put a bit of sealant between the gasket and water pump. I also put a bit of sealant on the cover face.

13)  Carefully mount the water pump back in place.

14)  Put 5 x 10mm bolts plus 1 x 10mm nut back in place and tighten to the required torque. I don't have a torque wrench, so the bolts & nut were done up firmly, but not overtight.

15)  Put the pulley wheel which sits behind the fan back in place. Put the 2 belts back on making sure they are facing the correct way. Tighten the belts to the required tightness using the 10mm adjustment bolt. Tighten the side 12mm bolt/nut and 14mm pivot bolt.

16)  Put aircon belt back on, again making sure it faces the right way and tighten using the adjustment bolt. When at the required tightness, tighten the 14mm aircon pulley nut.

17)  Put fan back on pulley wheel and do up the 4 bolts. Easiest to put the bottom nut on first and tighten so that it just bites onto the thread. Then locate the other 3 nuts. Doing it this way will save some skin on the knuckles. Tighten all nuts.

18)  Replace fan shroud locating the 10 or 12mm bolt. This is a bit of a mongrel job as the bolt sits almost directly under a hose, albeit the hose is flexible. Make sure that the upper shroud sits properly on the lower shroud otherwise you won't be able to locate the bolt into the hole. Also make sure this step is done BEFORE you put the egine cover and seat back on. I had forgotten about it and had to remove the seat & cover again, grrr...

19)  Put engine cover back in place and reattach the wire. Put the 12mm bolt which goes behind the handbrake setup and towards the rear of the engine block in place first, the put all remaining 12mm bolts back in place except for the one directly in front of the seat. Tighten all bolts up. Put all the carpet back in place, do this BEFORE putting the seat back in place. (I forgot and had to remove the seat a thrid time, thereby wasting more time, grrr....)

20)  Put seat back in place remembering to rejoin the wire cluster which sits to the front left of the seat. Put the last 12mm bolt which holds a bracket for the wiring cluster in place and tighten. Put the 4 x 14mm bolts which hold the seat in place and tighten. Don't forget the 14mm bolt which holds the strap on the LHS of the seat in place. Again, you may need to move the seat back or forwards to gain access to the bolts. Put the trim back over the wheel arch and tighten the 3 screws.

21)  Prepare some fresh coolant and fill up via the pipe where the radiator cap sits. Make sure that the radiator cap is on properly.

22)  Go for a drive, running the heaters so that coolant can flow to all parts of the system and expel any air pockets.

23)  When cool, check coolant levels and top up if necessary. Check for leaks as well.

I was quite proud of myself to having being able to do this as my mechanical skills are average. Just needed a bit of thought (and occasional phonecall to my mechanic!) and care.

Cheers,

Werner

Oops, forgot the most important part, the part number.

I got the pump through Sprint Auto Parts, part number WP3057, cost was about $80, but this may vary a bit from store to store. Can't remember the brand, but it wasn't Toyota.

Well done.

Thanks for that procedure Wernerk. I wouldn't have bothered removing the seat if you hadn't suggested it. I'm off to try it now. I have 6 to do so hopefully should get a procedure figured out by the end!