Builds HDJ77 Build for Midwest Overlanding (2 Viewers)

[GreaseMonkeyJP]

Well I got the new engine mocked up in place, and started making new engine mounts when I found a bit of an issue... There is no space left for the fan.

Remember when I said that I was glad that I caught that I needed the longer input shaft with this bellhousing well it turns out what I really needed was a shorter bellhousing. The long input shaft is ~2 1/4" longer and the engine is currently ~2 1/4" too far forward.

So now as I see it I have 3 options.
1. Move the Transmission: would require a fair bit of fabrication (cross member, center tunnel, prop shafts, etc.), and then the carpet would no longer fit.
2. Use electric fans: Actually there would be barely enough space for this. (<1” between belts and the fans) Also all other items connecting to the engine are off so it would require some modifications of other parts.
3. Find/make a new bell housing: My initial search leads me to the conclusion that the correct bell housing doesn't exist, so make maybe my only option. This will also require tearing down the transmission to change the input shaft back. However it would be the cleanest option.

I am currently leaning towards option 3 (I would be getting some help with making the bellhousing). Any opinions?

 

[GreaseMonkeyJP]

I noticed that the longer input shaft length on the new transmission is actually the same as what was used with the 1PZ. So I decided to just go ahead and stuff the 1PZ back in for a couple of weeks while I look into some options.

Already I can say that the new 5th gear is awesome. The 1PZ seams to really enjoy the new ratio on the freeway. I will see what it does for fuel efficiency.

 

[SNLC]

Not easy or cheap to make a bell housing. Almost all bell housings are cast, be it steel, aluminum or iron. I have worked with machinists a fair amount before and can tell you from that it may cost $3-5k to have a machinist turn up a custom bell housing. The chunk of steel alone to make it is going to cost a lot.

You might try talking to Advanced Adapters but also from previous experience I can say companies like this don't do one offs.

Cheers

 

[GTSSportCoupe]

Try looking at some other fan's that have less offset? Looks like if you could gain a 1/2" of room, you may be ok. Other Japanese Aisin style fans will bolt to the hub also, like from Isuzu etc. Just hunt around till you find one that will fit? Seems like the easiest option. Electric fans usually don't have enough power to do the job.

 

[bjowett]

Hydraulicly driven fan from an SC 400?

 

[GreaseMonkeyJP]

Not easy or cheap to make a bell housing. Almost all bell housings are cast, be it steel, aluminum or iron. I have worked with machinists a fair amount before and can tell you from that it may cost $3-5k to have a machinist turn up a custom bell housing. The chunk of steel alone to make it is going to cost a lot.

You might try talking to Advanced Adapters but also from previous experience I can say companies like this don't do one offs.

Cheers

Making one from scratch would be really difficult and time consuming. However I have one with all of the correct bolt patterns I just need to make the one I have shorter so it should just be some cutting and welding.

Unfortunately after second look the change with the shorter input shaft is less than 1.25". So this wouldn't get me all the way there.

 

[GreaseMonkeyJP]

Hydraulicly driven fan from an SC 400?

I didn't even know that hyraulic fans were a thing. I wonder how it is controlled.

 

[bjowett]

Lexus used them on the SC 400 and some 1st gen ES 300 cars. Toyota used them on the Camry V6 (ES 300 equiv.) from 92 - 94. The SC has a dedicated pump built in place of the fan pulley support bracket. The ES/Camry pump is also dedicated, but built into the housing of the regular PS pump, a double pump of sorts. A temperature sensor supplies info to a small dedicated computer that controls a solenoid valve which regulates flow and thus fan speed. They have a reservoir, cooler, and inline filter even. They are, IMO, one of the sweetest fan drive systems out there.

 

[GreaseMonkeyJP]

Now that's more like it

It is about 1" from the fan to the Radiator which should be sufficient.
Now to get everything else done.

 

[GreaseMonkeyJP]

Also if anyone was wondering I filled up before pulling the 1PZ, and the fuel economy for my one tank with the new 5th gear was 26.4mpg about a 10% increase from my normal.

 

[GTSSportCoupe]

Now that's more like it

It is about 1" from the fan to the Radiator which should be sufficient.
Now to get everything else done.

Looks great! What is that fan out of?

 

[GreaseMonkeyJP]

The fan is actually out of a Hilux of all things.

 

[GreaseMonkeyJP]

Well after driving with the 1HD for a couple of weeks there is bad news. The gas mileage was way down, and when I checked the oil level had gone up (despite a clear leak) so I am guessing there was diesel in the oil.

Also managed to set up a rough compression test (no one makes the correct adaptor for a 1HD-FT.) and got less than 100psi on cylinders 2 and 3.

I am hoping for just a head gasket but I will check everything and won't really know the extent of the rebuild until I get the head off.

So for now it is back out and the 1PZ is back in place.

 

[GreaseMonkeyJP]

And out it comes again:

On the good side I am now well practiced at swapping engines. The swap back to the 1PZ was completed in less than two days, including the exhaust re-routing, with plenty of time to spare.

Also I added the EGT probe onto the 1PZ exhaust. I figured that I might as well still put it to use.

My egt probe mount actually started out the morning as a stainless steel bolt. (Please ignore the poor welding on the rest of the exhaust)

 

[GreaseMonkeyJP]

Well I finally got the 1HD opened up

It looks like the head gasket did fail between cylinders 2 and 3, unfortunately it looks like head gasket bits left a little bit if scoring on the cylinder walls.

So it looks like it is time for a full rebuild...

 

[GreaseMonkeyJP]

Got the engine all town down and you can clearly see the damage on the No.2, and 3 pistons.

Out side of that the other cylinders looked literally barely broken in.

The block and head are now off to the machine shop. It will probably be close to a month to get the machining done and all parts gathered to re-assemble.

 

[bjowett]

Moly coating for the skirts on the new pistons. WPC Treatment is another option.

 

[GreaseMonkeyJP]

I am currently just thinking Toyota OEM pistons with no additional treatments. I am guessing that most of the piston damage came after the head gasket went and the cylinder walls were being washed down with unburnt diesel fuel due to the low compression.

Are you aware of any issues with the OEM pistons?

Also if anyone has suggestions on upgrades while I have it apart please let me know.

 

[bjowett]

Today, many OEM pistons, including diesels, come with moly coated skirts.... The benefits are well established and known. At a minimum, when building an engine, I have the piston skirts and rod bearings moly coated. Cheap insurance on top of slight efficiency gains. Swain Tech will coat piston skirts for $22 each, and 6 cylinder rod bearings for $35.50 a set.

 

[GreaseMonkeyJP]

Today, many OEM pistons, including diesels, come with moly coated skirts.... The benefits are well established and known. At a minimum, when building an engine, I have the piston skirts and rod bearings moly coated. Cheap insurance on top of slight efficiency gains. Swain Tech will coat piston skirts for $22 each, and 6 cylinder rod bearings for $35.50 a set.

So after a lot of looking into options my new pistons are off to Swain Tech to get moly coating on the skirts, and thermal barrier on the top. I tried to find someplace closer to do the coating, but I couldn't find anyone that had a better combination of quality for the cost.