Overheated 1HZ (1 Viewer)

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Yes, my number one priority is to get a better warning system once it's all installed. I've been doing a lot of research but still haven't decided what my after market sensor will be, just know it will likely go in the coolant outlet spot. If anyone has suggestions of their preferred strategy i'm all ears.

@mxtaco48 i hope your head turns out to be reusable!

Ive had one of these Engine Guardians or its competitor (Engine Watchdog) on all my landcruisers and I cant praise them highly enough for price, reliability and ease of installation and operation.
There is an ideal spot just forward of the transfer shift lever under the dash where they will sit nicely, but easy to see. You can plug them into the cig lighter or wire them direct to the battery or fuse box.
They are so light I had mine held on with double sided tape but they do have the ability to be held on with a bracket which is screwed to the dash

Seller below claims to be in Memphis USA.
 
@roscoFJ73 - reviving this thread as i'm getting ready to put a brand new head back in after year (what a saga!)


What size/thickness head gasket are you using?
 
I actually picked up the #5 before I knew there were different numbers. Plan on checking the protrusion when i start cleaning the block surface hopefully this weekend. Hopefully it turns out to be the right one...

With the watchdog, my understanding was it fits the sensor under any given bolt on the motor. I was worried this gives a less than accurate or at least not as real-time a temp reading as something in the flow of the coolant. Thoughts?
 
It's ok running too thick of a headgasket; just not too thin obviously. If you did run too thin, even the carbon on the piston/valves can touch. When people make this mistake on the 2LTE it takes out the big end bearings over time. Bang bang. With the 2LTE, people usually just buy the thickest one no matter what.
 
Aside, does anyone have an opinion on diesel having sat in the tank for 1 year. It's one of the things i'm kicking myself for not thinking to put some chemical in with it because i didn't expect it to sit this long. Drain tank, change fuel filter, refill? Or am i in for something more complicated?
 
I actually picked up the #5 before I knew there were different numbers. Plan on checking the protrusion when i start cleaning the block surface hopefully this weekend. Hopefully it turns out to be the right one...

With the watchdog, my understanding was it fits the sensor under any given bolt on the motor. I was worried this gives a less than accurate or at least not as real-time a temp reading as something in the flow of the coolant. Thoughts?
Having a gasket thats too thick will rob it of some power and possibly make it hard to start in very cold conditions.

I connected mine to the lower bolt on the upper coolant outlet. It probably does show a temp a few degrees cooler than the real temperature, but it gives you much better information than the OEM gauge. And you dont have to drill holes in anything.
And you soon come to realize what is normal and what is not. You look for consistency .

With the warning alarms, I had mine set a 75c, this showed me the temp was coming up from a cold start. The next warning beep was at 90c, this tells me the t/stat is working/opening. The final warning which I never used was set at 120c. The 90c warning was so reliable it would always come on in a 300 metre stretch of the freeway entrance. In summer it would come on at the beginning of the 300 metre stretch, in winter it would come on at the end of the stretch.
 
Aside, does anyone have an opinion on diesel having sat in the tank for 1 year.


No problems. But you could still put some fuel conditioner in there. Fuel conditioners make any moisture mix with the fuel and it goes out as steam(although you wont see it)

The real danger of fuel sitting for long times is in the fuel injection pump. If the fuel has very small amounts of moisture in it, it can sit on the highly machined surfaces and leave a corrosion mark.
But as water is heavier, it sits at the bottom of the tank or the water trap on the fuel filter.
I wouldnt do anthing more than fill it up with new fuel and go for a long drive with the new head.
 
I was just told by the local diesel shop that all injectors failed bench testing and need new nozzles. Quoted $610 USD total for 6 new nozzles shipped from Denso and pop test. Does that seem reasonable? I really didn't want to mess with replacing these after dropping the money for a new head and associated parts but cold starting was pretty rough and I guess it's the pill one must swallow.
 
Thats about what I paid when I had similar work down, about 60$ in parts each plus the labor.
 
Cool - anything else that should be taken into consideration when getting this labor done or parts to replace in regard to the injectors?

I saw somewhere to ask for flow matching? How important is that?
 
Let me tell you a story 🤣

This sounds eerily similar, although mine sat longer than yours did.
This "new diesel" sucks! It will go bad much faster than the old diesel did.

I sent my injectors in and they all failed as well, but they were able to clean them and get them working again. I decided since I was rebuilding the engine, might as well do the pump. Good thing, it was hammered, completely gummed/varnished up. The shop said this new diesel causes problems like this all the time. I also had to pull my fuel tank, clean it with lacquer thinner and all the fuel lines, filters were cleaned/replaced.
I would ask the shop that did the test if the fuel looked OK, or did they fail because they were gummed up/etc?

If it were me, I'd drain that tank no question, easy to do and see what that fuel looks like. Pull the sender out as well and shine a flashlight down in the tank. You will be able to see if it's nasty or not in there.

You "should" be alright if it's not all gummed/nasty, but if the pump has never been rebuilt, this might be the right time to do it along with injectors. A shop will be able to test/calibrate your IP as well and let you know what shape it's in. It might cost you $2~$300 to test the pump and is well worth it.
 
Thanks @FJBen - I actually dropped the injectors off by themselves since the truck is inoperable. They said they were sticking and had blueing. Being no expert, I assume in budget-speak that's "they work but they're not working well, and are worth dealing with now possibly as penance for blowing a head."

The IP has been weighing in the back of my mind as something to do soon but i figure I can cross that bridge if problems appear upon start-up because of costs to date.
 
I saw somewhere to ask for flow matching? How important is that?
Flow matching gets all the injectors flowing at the same rate. Its not vital but common sense says its got to be better.

The IP has been weighing in the back of my mind as something to do soon but i figure I can cross that bridge if problems appear upon start-up because of costs to date.

Getting the pump and injectors serviced at the same time is probably the best thing you can do for the injection system.
 
Long shot but does anyone have a trick to check valve clearance while the head is off the motor? Since I will have to rearrange several shims and possibly replace multiple with new shims, I'd rather pull the camshaft and reinstall it than use an SST. Is the SST just inevitable...?
 
Long shot but does anyone have a trick to check valve clearance while the head is off the motor? Since I will have to rearrange several shims and possibly replace multiple with new shims, I'd rather pull the camshaft and reinstall it than use an SST. Is the SST just inevitable...?

Usually the SST is only really needed for removing the shims when the engine is together. If the head is off the motor, you can take all your clearance measurements, then remove the cam, measure the shim thicknesses, and switch them around as needed. You could also remove the valves and have the stems ground to change clearances too. This is common practice for an automotive machine shop. Honestly I'd just let the machine shop do it all.... Usually doesn't cost much.
 
I was just told by the local diesel shop that all injectors failed bench testing and need new nozzles. Quoted $610 USD total for 6 new nozzles shipped from Denso and pop test. Does that seem reasonable?

Probably too late now, but I think its a bit expensive. But you are in the US and its a kind of tax you pay on engines not sold there. It is around $350USD in Australia for exchange injectors.
 
@GTSSportCoupe my conundrum is how to get the camshaft into the correct TDC position and the opposing position to take the measurements. How do you rotate it accurately without the timing belt and all connected?

@roscoFJ73 $350 USD would be a dream. When I compared similar services in the US it seemed like i couldn't get much less than 600. If anyone knows a cheaper alternative in the US please let us know for future reference!
 
@GTSSportCoupe my conundrum is how to get the camshaft into the correct TDC position and the opposing position to take the measurements. How do you rotate it accurately without the timing belt and all connected?

I think when I did it on my four cylinder head (2LTE), I used a couple pieces of old wood to suspend the head off the surface of the bench. This gave the valves clearance to open without hitting anything. I installed the cam pulley, and turned it clockwise using a rachet. It naturally wanted to stop in the right spots if I remember correct. Of course the 6 cylinder head might be different. Ideally you want to take the measurement when the cam lobe is pointing straight up away from the shim, but the radius of the cam shaft opposite the lobe is pretty consistent for many degrees, so it's ok if it's out a bit.

The 2LTE head uses the same valve spring/bucket/shim part numbers as the 1HZ. Even the valve is the same dimensions. They're not so different as people are led to believe...LOL.
 
I was just told by the local diesel shop that all injectors failed bench testing and need new nozzles. Quoted $610 USD total for 6 new nozzles shipped from Denso and pop test. Does that seem reasonable? I really didn't want to mess with replacing these after dropping the money for a new head and associated parts but cold starting was pretty rough and I guess it's the pill one must swallow.


New are about $150/each from Toyota.

Cheers
 

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