'93 HDJ81 - Turbo Upgrades and More (1 Viewer)

[GreenPump]

This summer, I acquired a 1993 HDJ81. Relatively high mileage at time of purchase, approximately 400,000 kms. I have several early and mid-90s Hilux, but this is my first 80 series. My initial impressions of the rig are very positive. More roomy and powerful than my other trucks, rides nice, and is happy at 120km/hr on the highway (will easily do 80mph which is the highway speed limit in these parts). The fuel consumption, however, is less than ideal. I struggle to get 250 miles out of a tank. Fuel capacity seems to be around 25 gallons. Plenty of grey/black smoke on startup, some grey/black smoke on heavy acceleration, nothing I would deem unusual for a diesel. Truck appears to have the "cold weather" package, although is not marked "snow version" like some others. Heated seats, fuel heater, and the weird blind which can be pulled down over the radiator. Starts on the first crank so far every time, we have had a few close to zero degrees F days, but nothing deep in the negatives yet. No obvious blow-by.

I performed the following maintenance items after purchasing the rig. Everything appeared to be kept up on, aside from BEBs, which were close to delamination.

• BEBs - ACL bearings & Conrod Bolts
• Transmission Maintenance (A442F Electronic)
  • All four solenoids replaced
  • Strainer replaced
  • Drain & refill with Redline DT4 ATF
• Front & Rear diff drain and refill with Amsoil SVG 75w90
• Transfer case drain and refill with Amsoil SVG 75w90
• Fuel filter & Petcock replaced
• Timing belt
• Water pump
• Glow plugs
• Engine air filter
• Oil Change & Filter - Amsoil Signature Diesel 15W40
• Grease all zerks (Driveshaft, spider joints, etc)
• Fluid film undercarriage for wintertime

As of this weekend, I pulled my turbo. Replacing the old and tired toyota CT26, which now has 420,000kms, has been on my radar for a bit. The stock turbo is beginning to leak fairly significantly into the intake side, and I am noticing oil coating the intake side of the block. However, I do not have any noticeable oil consumption on the dipstick. There does not seem to be excessive crankcase pressure.

I have read several threads on Mud about turbo kits; there are a plethora of options. But I am not sure if I have yet to come across my specific situation. I would like advice from those of you that have extensive experience in this area.

I am looking for a reliable setup which can bolt on to my stock exhaust and manifold with minimal or no modification. I would like to keep stock injectors and pump, although I understand I will need to tune my pump. Cost is a factor here; that being said, I would rather pay more for a reputable setup. I have looked at the PDI intercooler/airbox, but I do not know how important this really is. I would rather avoid the intercooler if it is not necessary. I have also considered having a local machine shop rebuild the stock turbo, I'm not sure if anyone has gone that route. I do a fair amount of towing, lots of highway driving, and I am almost exclusively at altitudes >5000ft.

Right now the Gturbo G300 green wheel seems like an attractive choice. I have ordered from HD Automotive in Australia in the past, but it looks like the kits can also be bought directly from Gturbo. Is there an American distributor? Kinugawa also seems like an "ok" option, but I am hesistant to put chinese/taiwanese parts on my rig.

Thoughts?

 

[GreenPump]

Update: Gillett Diesel south of Salt Lake will rebuild the stock CT26 for $625. Talking with them on the phone, they have done a couple of Toyota CT26s for 80 series. Turnaround time is 2-3 days. Sounds like a pretty good deal to me...

 

[mudgudgeon]

Update: Gillett Diesel south of Salt Lake will rebuild the stock CT26 for $625. Talking with them on the phone, they have done a couple of Toyota CT26s for 80 series. Turnaround time is 2-3 days. Sounds like a pretty good deal to me...

Do they have capability to swap the compressor wheel for a slightly larger 7mgte Supra compressor wheel? This would require the compressor housing to be machined to suit. Or source a 7mgte compressor housing.

Aftermarket versions of these two items can be sourced from Kinugawa or Mambatek.
Or OEM quality replacement parts from Mellett turbo in the UK.

7mgte compressor gives you a modest high flow upgrade for not a lot of dollars.

It keeps the original 40year old turbine technology, which is the biggest downside/ or the biggest upgrade potential.

7mgte compressor fitted to a 1hd-t turbine and CHRA was the original upgrade for these trucks before the aftermarket game stepped up.

 

[mudgudgeon]

Intercooler is not really necessary until you exceed 14psi.

You can get a lot more power and torque out of these with a fresh turbo, boost/wastegate set to 15psi ( maximum safe boost on the ct26) 3" exhaust, injector refresh, injection pump timing check, infecting pump tuning, valve clearance asjustment.

if you turn up the power output, EGT and boost gauge become essential.

 

[GreenPump]

Pulled the turbo apart today to get it ready for Gillett Diesel. I talked with them again today. Do I need to have an adjustable wastegate put on to open at 15 psi? Sounds like I will be safe with those numbers in stock form.

Wastegate seemed totally seized up on this bad boy.

A note on the exhaust manifold. Why does it come apart in two pieces? It seems there was a minor exhaust leak between the two halves. Replace the little metal rings/sleeve?

 

[GreenPump]

I also pulled off my intake manifold and injectors today. First time pulling the 1HDT injectors... it was an experience.

The injectors themselves came out pretty easy. I soaked in PB Blaster and wiggled them loose with a 10mm box end wrench.

The copper injector seats are much thicker than what I'm used to in the 3L engine. Three came out with the injectors (cylinders 1-3). Cylinders 4 and 5 I popped the seat out easily with a hook tool. Cylinder 6 the injector seat had become one with the head. It absolutely kicked my ass.

We're talking like, hood off the car, standing on top of the block, while letting loose all kinds of four letter words.

After a few hours I got it off. I ended up marring the head a bit. It's not terrible. It will probably still seal up. But very frustrating.

 

[TheBussman]

you can use a manual boost controller to up the boost if you have enough fuel and you get your drive pressure leaked sorted.

pretty normal to see some oil on the intake side of the turbo as it's after the crankcase vent hose.

having the exhaust manifold in 2 parts should reduce the chances of the manifold cracking as it can allow for expansion. there could be some production reason also.

 

[mudgudgeon]

Pulled the turbo apart today to get it ready for Gillett Diesel. I talked with them again today. Do I need to have an adjustable wastegate put on to open at 15 psi? Sounds like I will be safe with those numbers in stock form.

View attachment 3791867

Wastegate seemed totally seized up on this bad boy.
View attachment 3791866

A note on the exhaust manifold. Why does it come apart in two pieces? It seems there was a minor exhaust leak between the two halves. Replace the little metal rings/sleeve?

View attachment 3791870

You can use a bleed valve type boost controller to adjust when the waste gate opens.
Or purchase a Kinugawa ( or other) asjustable waste gate with a 15psi spring.

Yes, replace the rings in the manifold joint.
I think the rings come in a kit. Includes a couple of rubber o'rings and steel rings, and slip sleeve.
It's two pieces because a single piece manifold that long expands and contracts too much.

The old rings can be a pita to dig out.

 

[GreenPump]

I did my first valve job this weekend on the 1hd-t. Luckily my 3L valve tool is the exact same SST #09248-64011, which works for both. I've previously mentioned the poor gas mileage earlier in this thread... well, that is all making sense now. Gillett diesel tested the injectors yesterday, and they need new nozzle tips (no surprise there).

The truck has been sitting several nights in the shop, so it was definitely a "cold" reading. Once I got the wood stove going, I did my clearances at room temperature. Not one, or two, but EVERY SINGLE valve clearance was out of spec. All the exhaust valves were too tight measuring between 0.23-0.28mm. Intake valves were all too tight as well, aside from cylinder 6 intake, which was too loose... weird.

As I went along, I thought maybe something was up with my feeler gauges. I had a second set, so I double checked everything. Both sets of feelers returned the same reading. I did the same process when measuring shim thickness, I doubled checked the readings from my Starett calipers with my Mitutoyo calipers. Measured clearance is shown in blue pen, shim thickness in black.

Ordered a bunch of new shims, and now we wait.

 

[GreenPump]

As for the turbo: Luke at Gillett diesel started to tear down the turbo for a rebuild, and the turbine housing is cracked pretty significantly. @Owyhee Jackass has a CT26 off of a 14BT, which already has the 14psi actuator. I believe this turbine housing is identical to mine and will work for a rebuild? We are both in Idaho, it could work out.

Anyone able to confirm this?

The numbers on the housing match up... #68020

 

[mudgudgeon]

As for the turbo: Luke at Gillett diesel started to tear down the turbo for a rebuild, and the turbine housing is cracked pretty significantly. @Owyhee Jackass has a CT26 off of a 14BT, which already has the 14psi actuator. I believe this turbine housing is identical to mine and will work for a rebuild? We are both in Idaho, it could work out.

Anyone able to confirm this?

View attachment 3794780
View attachment 3794781
The numbers on the housing match up... #68020

If the housings are both original Toyota, and not a reproduction, the matching numbers is what you want.

Aftermarket reproduction castings often have the wrong numbers.

 

[Owyhee Jackass]

We're both in Idaho, but on the opposite side of the state. Let me know if you need more pics or measurements.

Dan

 

[GreenPump]

We're both in Idaho, but on the opposite side of the state. Let me know if you need more pics or measurements.

Dan

Hey Dan,

Just wanted to confirm if this is the original toyota housing. It looks like the number stamped on it is 68020?

Hopefully your housing is in good shape- cracks can be hard to see but will be on the exhaust side, many times around or behind the wastegate.

I will send you a direct message to figure out the details if your housing is crack-free.

 

[GreenPump]

So unfortunately we are looking at two cracked turbine housings

The one Dan has failed in exactly the same spot.

I spent all day today reading up on Mambatech, Arashi, and Kinugawa. They all are similarly priced and come out of Taiwan. The more I dig into these brands, the sketchier they seem. All sorts of horror stories from other car forums, not just Toyotas.

That leaves me with a few options. The Gturbo green wheel seems like it is going to be more than I need. I want to run a 1.0 bar actuator, which I believe is between 14 and 15 psi?

What about the UFI 16G?

Any other brands which could be comparable to the stoutness of a stock CT26?

I am now firm on no intercooler. One thing is for sure, I want to put this thing on and not worry about it for a decade, just like the original.

 

[bcsteel]

Hx30?

 

[GreenPump]

Hx30?

I didn't know this was an option... I found a couple Australian offroad sites advertising it for the 1HDT though...

What modifications required to fit it to stock manifold

 

[bcsteel]

I have not had both in my hands but it seems like it’s been done quite a few times. Cheap alternative to Gturbo or wink and probably just as good.

sins 4x4 has quite a few options it looks like.

 

[cgmud]

I would find a CT26 and get it refurbed like you’re originally looking for. I have one still. I’ll check to see if it has the crack you’re talking about.

 

[KiwiDingo]

Where's the crack exactly?

 

[Owyhee Jackass]

This is where mine's cracked, his is in the same spot.