where the F is the block drain for coolant (1HZ) (2 Viewers)

[BreckenridgeCruiser]

the title says it all.

I'm trying to get some preventive maintenance done and want to get all the crap out of my block and radiator. I know where the petcock is on the radiator obviously, but I cannot seem to find the engine block drain for coolant. I think that will help get all the crap out of my block before getting intonthe rad.

pictures would be exceptionally helpful!

 

[IanB]

Assuming it's the same as the 1HD-T (and I don't know why it would be any different unless the 1HZ doesn't have an oil cooler), there's a coolant drain on the injection pump side of the block, on the oil cooler cover just behind the injection pump, accessible from the LHS wheel well (you'll have to remove the wheel/tire to get in there). It's the same one many guys use for a circulating coolant heater install, they run a hose from here to the inlet of the coolant heater.

Here's a link to that thread, there's a pic of the drain location on page 4, and an FSM drawing on page 2.

https://forum.ih8mud.com/threads/circulating-heater-install-on-1hdt.539931/

 

[Squash]

As above no need to remove tire, just use a socket and long extension, you may have to lift the rubber liner to really see.
The HDT is straight the 1HZ fitting may have a small elbow attached.

 

[Squash]

Pictures.
Top is typicall 1HDT, bottom is 1HZ.

 

[BreckenridgeCruiser]

So... After all of the info you guys posted. I don't think I have a drain...

Here are some pictures of the area it is supposed to be. Am i missing it or did a PO put a bolt in instead of a drain? Could I not have on on this engine?

 

[roscoFJ73]

Do you have a 1HZ FSM? It is clearly shown in the Lubrication section in a diagram on page LU15. If you dont have a manual,there is the page you want in IanB's link.
LU17 has an even better diagram showing the bolt inserted into the oil cooler

 

[roscoFJ73]

From memory ,the point at which the drain is , is the lowest point of the coolant system in the engine block.Obviously it is in the oil cooler
Pictured circled in yellow from an engine I rebuilt a few years back.

After studying your pics ,it does look like someone replaced the brass fitting with a bolt

 

[lostmarbles]

I just did a search and some bloke in Oz (Ken) reckons that from 1998 the engine drain plug was deleted.

http://www.exploroz.com/Forum/Topic/25430/HZJ_75_Engine_1hz_engine_coolant_drain_plug.aspx

Is this relevant to the discussion here?

 

[OGBeno]

I just did a search and some bloke in Oz (Ken) reckons that from 1998 the engine drain plug was deleted.

http://www.exploroz.com/Forum/Topic/25430/HZJ_75_Engine_1hz_engine_coolant_drain_plug.aspx

Is this relevant to the discussion here?

View attachment 1085050

5/1998 and later the drain cock on 1HZ engines was moved from the oil cooler housing just to the right (moving rearward) of the oil cooler.


So it went from the oil cooler to the block.

It should be a 14mm bolt head drain cock. Brass.

IMO, as stated above, someone replaced the drain cock with a bolt.

 

[lostmarbles]

Thanks Beno..

Maybe that introduction date changed with the market because here's a General-Market image from the EPC showing the block-location for the drain cock for a 1HZ occuring from January 1998:

Looks like it's just down and forward of the heater feed elbow..

I could be wrong, but I don't think any of Kraig's photos look quite at this area.

I should have known not to rely on other Internet posts. ... (Much better to refer to Toyota's own information.)

 

[BreckenridgeCruiser]

I'll look there tomorrow! Pics too. Thanks guys!

 

[roscoFJ73]

The one in Marble's diagram appears to be where the Australian 1HZ had a water temp sensor for the glow system on the older models circa 93.
I remember removing it when I stripped the engine down for a rebuild but the sensor was non functioning. I might have it somewhere in my nut and bolt bucket.

 

[BreckenridgeCruiser]

So I checked the other location and it seems that I have the sensor on the rear location (my engine was set for superglow) and that bolt on the front. Looks like I need to source a drain to make sure I can clean the block properly.

Thanks everyone! I thought I was losing my mind for a second there!

 

[Hooligan327]

I realize that this is an older post. I got here looking for block heater options. I'm considering putting an inline circulating heater on my 1Hz. That would entail connecting it from the "Engine Drain Cock" to the heater hose before the cab heat control valve. Anyway, I was trying to figure out the specs (threads) for the drain. Then I went to my service manual, and I still wasn't able to find the information I was looking for. However, I found this and thought it might be relevant to the above discussion. Maybe it will help someone else; if not, feel free to ignore this post.