1994 2nd Gen Hilux Surf 3.0 turbodiesel 'Sasquatch'
- Thread starter pyemaster
- Start date
Saint Nick
Active member
Very nice work Owen 
Nick
Nick
toastyjosh
Adventurer
PICs of the 35s!!!
I'm a Minnesotan and imported a 1995 KZN130 just last summer. I've begun building it up into my overlanding rig, especially since the gf and I took a 2 week "budget overlanding" trip earlier this summer.
Your post made me join this forum just to ask some questions.
What was the reason for the head replacement? Did the truck overheat and warp the heads on you?
Where did you find the 71 degree thermostat? I've been looking for one for a while, and only come up with the 82 degree one.
Can you post some pictures of your interior organization?
Do you have cruise control retrofitted?
At the moment, my surf sits mostly stock with Aisin manual locking hubs and a few maintenance items all buttoned up. I have most of a 2" suspension lift kit ready to go in, then will be 33's, and a roof rack.
Pic related is an old picture of the truck that I have saved on my computer. Shipped it in with 70,000km on the odometer.
Your post made me join this forum just to ask some questions.
What was the reason for the head replacement? Did the truck overheat and warp the heads on you?
Where did you find the 71 degree thermostat? I've been looking for one for a while, and only come up with the 82 degree one.
Can you post some pictures of your interior organization?
Do you have cruise control retrofitted?
At the moment, my surf sits mostly stock with Aisin manual locking hubs and a few maintenance items all buttoned up. I have most of a 2" suspension lift kit ready to go in, then will be 33's, and a roof rack.
Pic related is an old picture of the truck that I have saved on my computer. Shipped it in with 70,000km on the odometer.
Attachments
Hello surf_baka,
Great choice! If you change the oil regularly and make sure your cooling system is efficient, these engines will go forever.
I bought mine stock. Unfortunately for me the garage that did the service when I got it didn't bleed the system properly and it overheated within 10 minutes of me driving it away. They took no responsibility and it took me 3 months to get them to agree to fit the new head, gasket, bolts, etc. Been perfect ever since, the replacement head is cast from much better grade aluminium I believe. I also make sure it's bled properly every time the coolant is changed! (They hadn't realised the Japanese imports come with the rear heater, and thus hadn't opened up the system for the rear pipes).
For peace of mind, I'd check your rad is flowing fine, with good fins and no blockages of crud in there. Upgrade to a 10-blade Hella fan and get the viscous hub kicking in a little sooner with thicker oil. Fit an external oil cooler if it's an auto to take some of the heat out of the bottom of the rad. I removed my AC system and AC rad to improve flow, and moved the fan for that to suck more air through the main rad on a standalone button in the cab. That's my '******** this is a long hill on a hot day switch'. Maybe knocks a degree or two off the top hose temp, every little helps.
I can't remember where I got the lower thermostat from, but it was online, I found discussion about it on some forums, so have a dig around, it may have been the Ozzies who pioneered that little idea. Worked great over the last few years.
I'll try and get some pics of the interior for you, I built and carpeted some full-length, full-width, low-profile drawers (4" high) which run from the tailgate to where the rear seats hinge. Then there's a detachable storage floor which I slot in to create a flat sleeping platform. Under that are additional storage compartments for recovery gear, straps, etc.
I never bothered with cruise control as it would need to be retrofitted and I just felt was a potential 12v weak spot with the wiring, plus I felt it's a luxury item I didn't really need. I've tried to keep all the modifications to Sasquatch simple, so they can be bushfixed quickly when on a trip if needed.
Will try and get some pics for you!
Owen
Great choice! If you change the oil regularly and make sure your cooling system is efficient, these engines will go forever.
I bought mine stock. Unfortunately for me the garage that did the service when I got it didn't bleed the system properly and it overheated within 10 minutes of me driving it away. They took no responsibility and it took me 3 months to get them to agree to fit the new head, gasket, bolts, etc. Been perfect ever since, the replacement head is cast from much better grade aluminium I believe. I also make sure it's bled properly every time the coolant is changed! (They hadn't realised the Japanese imports come with the rear heater, and thus hadn't opened up the system for the rear pipes).
For peace of mind, I'd check your rad is flowing fine, with good fins and no blockages of crud in there. Upgrade to a 10-blade Hella fan and get the viscous hub kicking in a little sooner with thicker oil. Fit an external oil cooler if it's an auto to take some of the heat out of the bottom of the rad. I removed my AC system and AC rad to improve flow, and moved the fan for that to suck more air through the main rad on a standalone button in the cab. That's my '******** this is a long hill on a hot day switch'. Maybe knocks a degree or two off the top hose temp, every little helps.
I can't remember where I got the lower thermostat from, but it was online, I found discussion about it on some forums, so have a dig around, it may have been the Ozzies who pioneered that little idea. Worked great over the last few years.
I'll try and get some pics of the interior for you, I built and carpeted some full-length, full-width, low-profile drawers (4" high) which run from the tailgate to where the rear seats hinge. Then there's a detachable storage floor which I slot in to create a flat sleeping platform. Under that are additional storage compartments for recovery gear, straps, etc.
I never bothered with cruise control as it would need to be retrofitted and I just felt was a potential 12v weak spot with the wiring, plus I felt it's a luxury item I didn't really need. I've tried to keep all the modifications to Sasquatch simple, so they can be bushfixed quickly when on a trip if needed.
Will try and get some pics for you!
Owen
Owen,
Thanks for the info. I've delved into the known problem of 1KZ-TE cooling and will sum up the common fixes for my reference and anyone else that happens into this thread. These answers are usually spread out among multiple threads and pages. I'll put them all right here:
OE Fixes:
Replace radiator with new aluminum radiator. (gunk buildup)
Replace/clean radiator hoses. (gunk buildup)
Drain and replace viscous fan oil with 40-60 mL of 7000-10,000 CST oil. (Kick on fan sooner. Factory generally uses 3000 CST oil and underfills at 20 mL. Overfilling will engage fan all the time, reducing MPG)
Install lower temperature thermostat (71C Prado thermostat: Part #90916-03121. 76C thermostat: Part #90916-03119. Factory thermostat placement does not monitor 'true' coolant temp coming out of engine. Preempt this with a lower temp thermostat or move thermostat location to radiator inlet at top of engine. Stock thermostat placement also results in temperature 'cycling'/pulsing between 50C and 88C due to slow feedback response of thermostat. The 'cycling' introduces excessive expansion and contraction on the head and studs.)
Remove EGR valve and blank off (gunk buildup, restricts air intake; heightens engine temp)
Remove Venturi/Butterfly plate (restricts air intake; part of EGR system)
Ensure water pump is operational (don't mix an aftermarket water pump front half with an OEM rear half. The impeller and housing interior clearance can be as large as 8mm, making for a useless pump. Proper clearance should be <2mm with both Genuine halves. Don't get lazy, replace both halves with Genuine Toyota parts.)
Stock water temperature gauge resistor fix (stock temp gauge known to be 'numb' caused by poor quality resistor components.)
Higher quality viscous fan
Clean/New air filter / high-flow filter (less air restriction)
Blank off / Remove second row rear heater matrix (simplify cooling system? Less potential problems?)
Modifications:
Thermostat relocation to Radiator inlet (Jegs in-line 1 1/2" thermostat housing w/appropiately paired thermostat)
Separate transmission cooler (Have read this may not be true fix as the original Toyota design is an efficient oil-water heat exchanger)
Turbo Intercooler (reduce coolant temps via separate turbo cooling)
Larger diameter Turbo downpipe (remove the hot exhaust gases faster/sooner; lower turbo temperature)
Larger diameter turbo-back exhaust system (same reason as above)
Aftermarket reliable coolant temperature gauge for monitoring
Pre-turbo exhaust gas temperature (EGT) gauge for monitoring (absolute best indicator of the engine's realtime condition.)
Driving Behavior:
Don't use overdrive on steep hill climbs
Keep RPM between 2500-3000
Keep towing weights low (ideally, don't tow at all)
In short, Toyota was very close to an excellent product of an engine. I would say having a gunk-free cooling system, viscous fan re-oiling, thermostat relocation + lower temp thermostat, EGR valve + venturi plate removal would be the top things to address. Most overheating problems here are apparent when towing trailers up hills. Personally, I don't tow at all, so I'm not terribly worried. I did bump the temp gauge to exactly 50% (normal is 40% on mine) while wheeling out in Colorado, but hopefully that wasn't enough to cause any real damage. All that being said, I will likely have a spare complete head on standby if the head decides to go anyway.
I also look forward to seeing your drawer system. I've decided to fab my own racking that will accommodate up to 8 Dewalt weatherproof toolboxes for gear organization/modularity. It goes without saying, I'm not sleeping inside the Surf. I also have bumpers and armor on the way and will be putting on a Smittybilt roof rack. Keep a lookout for my surf's thread of it's own in the future.
And I have to say, you are a mad man pulling the A/C out like that. My Surf's compressor went out early this summer and I was without A/C for like 60 days. It was awful. But if you can deal with the heat, the simplicity is nice.
Also, I would suppose being in Europe, cruise control wouldn't be totally needed. In the US, doing 12 hours on the freeway is hell having to switch feet on the gas pedal all the time. One doesn't really appreciate cruise control until you don't have it.
surf_baka
Thanks for the info. I've delved into the known problem of 1KZ-TE cooling and will sum up the common fixes for my reference and anyone else that happens into this thread. These answers are usually spread out among multiple threads and pages. I'll put them all right here:
OE Fixes:
Replace radiator with new aluminum radiator. (gunk buildup)
Replace/clean radiator hoses. (gunk buildup)
Drain and replace viscous fan oil with 40-60 mL of 7000-10,000 CST oil. (Kick on fan sooner. Factory generally uses 3000 CST oil and underfills at 20 mL. Overfilling will engage fan all the time, reducing MPG)
Install lower temperature thermostat (71C Prado thermostat: Part #90916-03121. 76C thermostat: Part #90916-03119. Factory thermostat placement does not monitor 'true' coolant temp coming out of engine. Preempt this with a lower temp thermostat or move thermostat location to radiator inlet at top of engine. Stock thermostat placement also results in temperature 'cycling'/pulsing between 50C and 88C due to slow feedback response of thermostat. The 'cycling' introduces excessive expansion and contraction on the head and studs.)
Remove EGR valve and blank off (gunk buildup, restricts air intake; heightens engine temp)
Remove Venturi/Butterfly plate (restricts air intake; part of EGR system)
Ensure water pump is operational (don't mix an aftermarket water pump front half with an OEM rear half. The impeller and housing interior clearance can be as large as 8mm, making for a useless pump. Proper clearance should be <2mm with both Genuine halves. Don't get lazy, replace both halves with Genuine Toyota parts.)
Stock water temperature gauge resistor fix (stock temp gauge known to be 'numb' caused by poor quality resistor components.)
Higher quality viscous fan
Clean/New air filter / high-flow filter (less air restriction)
Blank off / Remove second row rear heater matrix (simplify cooling system? Less potential problems?)
Modifications:
Thermostat relocation to Radiator inlet (Jegs in-line 1 1/2" thermostat housing w/appropiately paired thermostat)
Separate transmission cooler (Have read this may not be true fix as the original Toyota design is an efficient oil-water heat exchanger)
Turbo Intercooler (reduce coolant temps via separate turbo cooling)
Larger diameter Turbo downpipe (remove the hot exhaust gases faster/sooner; lower turbo temperature)
Larger diameter turbo-back exhaust system (same reason as above)
Aftermarket reliable coolant temperature gauge for monitoring
Pre-turbo exhaust gas temperature (EGT) gauge for monitoring (absolute best indicator of the engine's realtime condition.)
Driving Behavior:
Don't use overdrive on steep hill climbs
Keep RPM between 2500-3000
Keep towing weights low (ideally, don't tow at all)
In short, Toyota was very close to an excellent product of an engine. I would say having a gunk-free cooling system, viscous fan re-oiling, thermostat relocation + lower temp thermostat, EGR valve + venturi plate removal would be the top things to address. Most overheating problems here are apparent when towing trailers up hills. Personally, I don't tow at all, so I'm not terribly worried. I did bump the temp gauge to exactly 50% (normal is 40% on mine) while wheeling out in Colorado, but hopefully that wasn't enough to cause any real damage. All that being said, I will likely have a spare complete head on standby if the head decides to go anyway.
I also look forward to seeing your drawer system. I've decided to fab my own racking that will accommodate up to 8 Dewalt weatherproof toolboxes for gear organization/modularity. It goes without saying, I'm not sleeping inside the Surf. I also have bumpers and armor on the way and will be putting on a Smittybilt roof rack. Keep a lookout for my surf's thread of it's own in the future.
And I have to say, you are a mad man pulling the A/C out like that. My Surf's compressor went out early this summer and I was without A/C for like 60 days. It was awful. But if you can deal with the heat, the simplicity is nice.
Also, I would suppose being in Europe, cruise control wouldn't be totally needed. In the US, doing 12 hours on the freeway is hell having to switch feet on the gas pedal all the time. One doesn't really appreciate cruise control until you don't have it.
surf_baka
Yeah great post mate, covered off all the big ones there, most of which I've done on mine. There are a few things I've yet to do, like move the stat to the top pipe, but I've not felt I've needed to as yet. On the flat when not pushing hard it cruises at around 80-85C. I've also got a high flow K&N air filter, removed all the rear heater pipework and fitted a good quality aftermarket Auberins digital temp sensor in the top pipe to keep an eye on things. Don't worry too much on the engine temp creeping over halfway on long climbs out in hot temps. So long as it comes back down again that shows things are operating as they should. Climbing over the Alps I had mine up to three quarters and even higher, but it quickly came back down again after cresting the peak, as it should. Just shows a hot engine working hard under load. It's when it doesn't come back down again you need to worry...
I don't tow but still have a fair amount of kit on board which means I take it gentle on hills. I try not to go over 2.25k rpm if I can help it. I've definitely found having the external oil cooler helped the coolant system drop the temps down. While the heat exchanger idea is sound in theory, in practise it doesn't hold up. There's an argument against having a bigger turbo downpipe too. I've kept mine the same diameter, as after speaking with an exhaust builder he said going too large on this pipe doesn't actually help lower turbo temps a great deal - having the smaller stock diameter pipe speeds exhaust gases and heat through, where a bigger pipe allows for slower release and hotter temps at the turbo. In reality, it's probably marginal.
By the way having an exhaust any bigger than 2.5" on this engine will only serve to rob you of torque. This is the sweet spot in my opinion - opens things up and allows greater flow while keeping your low end grunt and not getting caught up in the 3" arms race of sacrificing it for more 'power'. Let's be honest, noone buys these engines for speed and power
I've currently got my EGT sensor wired up and resting on my dashboard, haven't got around to getting it fitted pre-turbo as yet. Aiming to get this done by the end of the year for peace of mind. Interestingly it has proven my dashboard has reached 80C this summer though.
Although my AC was ice cold, I reasoned I'd rather be too hot and open the windows than let the engine get too hot, it also creates SO much more room in the engine bay to work on things, and has probably removed most of the weight of my winch!
I hear you on the long drives, I've very much welcomed cruise control on all the trips in standard cars I've done across the states, there are big days out there, but I've also gone across Australia a few times without it, and done 1,000km days across Europe without it and not felt the need for it too much if I'm honest. Different strokes for different folks - definitely worth retrofitting it if it's something you're used to though for sure.
Definitely need to see pics of yours!
Best
Owen
I don't tow but still have a fair amount of kit on board which means I take it gentle on hills. I try not to go over 2.25k rpm if I can help it. I've definitely found having the external oil cooler helped the coolant system drop the temps down. While the heat exchanger idea is sound in theory, in practise it doesn't hold up. There's an argument against having a bigger turbo downpipe too. I've kept mine the same diameter, as after speaking with an exhaust builder he said going too large on this pipe doesn't actually help lower turbo temps a great deal - having the smaller stock diameter pipe speeds exhaust gases and heat through, where a bigger pipe allows for slower release and hotter temps at the turbo. In reality, it's probably marginal.
By the way having an exhaust any bigger than 2.5" on this engine will only serve to rob you of torque. This is the sweet spot in my opinion - opens things up and allows greater flow while keeping your low end grunt and not getting caught up in the 3" arms race of sacrificing it for more 'power'. Let's be honest, noone buys these engines for speed and power
I've currently got my EGT sensor wired up and resting on my dashboard, haven't got around to getting it fitted pre-turbo as yet. Aiming to get this done by the end of the year for peace of mind. Interestingly it has proven my dashboard has reached 80C this summer though.
Although my AC was ice cold, I reasoned I'd rather be too hot and open the windows than let the engine get too hot, it also creates SO much more room in the engine bay to work on things, and has probably removed most of the weight of my winch!
I hear you on the long drives, I've very much welcomed cruise control on all the trips in standard cars I've done across the states, there are big days out there, but I've also gone across Australia a few times without it, and done 1,000km days across Europe without it and not felt the need for it too much if I'm honest. Different strokes for different folks - definitely worth retrofitting it if it's something you're used to though for sure.
Definitely need to see pics of yours!
Best
Owen
