06/94 1KZ-TE - flushing the cooling system

Hi all,

I need to give the cooling system a flush & refill it with coolant, preferably sooner than later.

I have a few questions :

Are the 2 radiators connected?

Is the drain plug on the horizontal radiator for both radiators or only the horizontal one? I have yet to take off the bash plates for a proper look at the bottom end of the vertical radiator.

The draining procedure would I assume include draining the radiators, the engine block (where is the best drain point for this?) & overflow reservoir.

What is the total capacity of the cooling system (auto transmission)?

Is the flushing procedure relatively easy and NON-MESSY (to avoid an earbashing re mess )?

I am assuming the procedure is as follows :

Once system has been drained, it's filled with flushing, then the engine is left running with the heater on for about 10 minutes so that the heater are is flushed as well? After cooloing, drain the flushing solution, then refill with coolant, again running the engine with heater on and radiator cap off, topping up coolant as the level drops?

Does that about basically cover it? Anything special to look out for? Have I missed anything?

I have tried to find some of the answers on the forum but haven't had much luck.

regards,

Werner

Hi Werner,

I can't even find the posts that I have read before about changing the coolant. The thread mustn't have the terms I'm searching for as keywords.

According to my handbook the cooling system is 13 litres but it doesn't differentiate between auto and manual.

Nulon radiator flush & clean says 20 minutes to do the job. You would need to run it for 20min after the thermostat has opened (up to normal temperature on the gauge) and be sure to have front and back heaters on. The radiator flushes I have used before can stain concrete ( I think thay are alkaline) with a whitish residue. I usually do this sort of thing over my font lawn which always recovers quickly. If you have glycol in the system the grass may not like it but it sounds like you don't. (my mate once nuked his mum's lawn with glycol - it grew back after about 6 months) .

I'm sure someone else will be able to help you with the rest. If I can find those posts I know exist I'll point you there.

Hi Dave,

the 13 litres is a good start, I'll make up some extra in case. The "owner's manual" which came with the car is very basic and goes into things such as fastening seatbelts etc.

Where did you get your handbook from?

Hmm, just remembered that there was an uploadable/downloadable workshop manual, will have to go through that to see if I can find the answers.

regards,

Werner

owners manual can be had from www.jpnz.co.nz
cheers another dave

Thanks for the link to the owner's manual, Dave.

I had a look at the online workshop manual and realised that it was mainly intended for the Prado or Surf as it only had the one radiator.

I think I'm going to have to put her up on the ramps again and remove the bash plates to see how the cooling system is all interconnected. Maybe take some pics & try and post up to confirm or otherwise the drainage points.

By the way, where do your temp gauges normally sit? Mine sits at either exactly midway or slightly below, depending on traffic flow.

Cheers,

Werner

yes mine sit in the same spot all day long just below half way
cheers the other dave

I have copied the post (in quoyes) from the "servicing 1KZ-TE - some questions" thread to this one as it's more relevant here.

"I have had a thought about the whole cooling system issue and also spoke to the RAA technical service as well as a caryard in Sydney which services these vans.

I have decided to have a "rise" test done to rule out any exhaust gases in the coolant=cracked head, then if that comes back ok, I'll get the whole system flushed by a radiator place and get some decent coolant put in, probably am going to go with the Toyota coolant as I aim to have my van for quite some time to come yet. Bit more expensive, but peace of mind. (Total cost flush + rise test ca $187 with Toyota coolant)."

Update:

I had the "rise" test done and confirmed the head was ok. Also confirmed that there was a very weak coolant in the system. Took the van to the radiator place next door, but he said although he would like to be able to have done the job, he wasn't able to as he said doesn't have a hoist to be able to access the vehicle from underneath to be able to drain & clean the system properly.

This guy has been in the radiator business for a long time so he should know what he's doing and he seemed to be honest to me. He gave me a list of 3 other places to go to who in his opinion would be able to do the job properly. Also told me of a few places to avoid as well.

I went to the place at the top of his list, but he said he was unable to help me. Seems like the position of the thermostat is the stumbling block. Anyway, I'll try the other 2 this week. If I draw a blank with them as well, I'll wait until my mechanic returns from overseas mid May and see what his thoughts are.

Meantime, I'll just keep an eye on the coolant levels as well as the temp gauge.

Hi, I have some questions related to the thermostat.

I took the front wheel off & pulled back the rubber strip & had a look for the thermostat.

Is the part labelled as "T" the thermostat housing in this photo? Are the 2 bolts labelled as "A" the only bolts holding it in place?



In the following view, what are hoses H1 & H2 for?



Apart from the 2 bolts labelled as "A" in the first photo, what else needs to be undone/removed so that the thermostat can be accessed for flushing?

Is it easier to get to the thermostat through the wheel arch or by removing the seat & floor panel?

cheers,

Werner