Hi All,
Have wanted to get a 4wd for ages and last year I decided I had spent to longing sitting in the passenger seat while my mates were four wheel driving.
So in December I picked up a 91 1HZJ75 with aftermarket turbo. Took her down near augusta. Had a blast 4WDing around the forests there and did another run to Brunswick junction which was a bit more technically challenging. Absolutely loved it!
But....
On the run down to Augusta, and the return she overheated (went to 3/4 and didnt look like stopping till I backed off), could only manage about 95~100 safely. Also found it doesnt like hills, the hill up welshpool road to kalamunda does it every time. It doesnt overheat cruising the city and you can 4WD all day, even on the steep inclines at Brunswick and the needle doesnt move.
I had hoped to post something once I had figured out the solution as it seems to be a pretty common problem. I was toying with the concept of an intercooler until I went up the hill at night with 20 degrees ambient, it did the same thing as a 40 degree day - and I dont believe the intercooler will drop the intake temp by more than 20 degrees.
Anyway, I spent a fair while googling, and was excited to see that 1HZs without turbos do the same thing - so at this point I was pretty convinced it was the coolant system.
I replaced the thermostat (which is not easy to get to with the afermarket in the way) - it didnt do to well on the boiling water test but didnt seem that terrible. Recommendation to anyone going through this, its that hard to get to the thermostat and there only about $30 dont worry about testing it, just replace it, be careful with the gasket, mine slipped out a bit, pinched and I put the whole thing back together before I realised it was leaking
I replaced the fan belts and the viscous clutch ($175 at repco). The old clutch didnt really seem to bad. The old belts definately needed some tension.
No improvement
I had a new pump to put in($140 at repco), and here Id like to say a big thankyou for nothing to to the publisher of gregorys automotive manuals who didnt mention you need the timing belt off to do the water pump . Put it all back together again and picked up a new timing belt kit ($215 at repco - seeing I was going to take it apart anyway). Pulled it apart again, swapped out the pump, worth doing, the bearing was clicky. Succesfully rebuilt the timing belt and in the process realised the ******* I had bought it off had used silicon to seal the rocker cover where he had pinched the gasket once - down to repco - new gasket ($15 at repco).
No improvement
Amidst all this I had bought an infrared temperature gun from supercheaps ($30). Did some testing, found the radiator ran about 87deg at the top inlet and about 50~55 at the bottom outlet. Also, believe I can definately say the temperature guage is not faulty as when its reading 3/4 on the dash the temperature gun is showing 95deg at the top of the radiator and surprisingly about 87~90 at the bottom - couldnt really figure out what the high reading on the top meant but discounted the gague on the dash.
Time for a new radiator, picked one up at radiator wholesalers ($350). Went to put it in that weekend - it was the wrong one. To their credit they swapped me one out the next week. Replaced the radiator next weekend.
No improvement
I would have been tearing my hair out at this point but fortunately in parallell I had been working to install a boost guage. (I found a good example from a website on where to tap in and copied that - it came up really neat. Can provided instructions if required). On the run to my testing ground (the hill up welshpool road) I realised that the turbo was putting in 15psi of boost at 100kph. Bingo I thought - way too much boost.
Next weekend pulled out the wastegate, pressure tested it, it opens at 15psi. Couldnt really solve that then but decided to wind out the clevis on the end of it. Got the boost down to 5~6psi max at 100kph and about 7psi going up the hill.
NOTE : at this point I was already very paranoid about a cracked head, even though there were none of the signs (no bubbles in the radiator, no oil in the water, no water in the oil, expansion tank not overflowing). I bought a radiator leak tester($200 at coventries) and a block tester ($150 at coventrys). FYI the radiator leak tester is great, when I detected a 1psi drop over 1minute I traced it to a loose hose clip that only produced 1 single drop that didnt even drop off in that 2 minutes. Fixed that and it held pressure for half an hour. So, no leaks under rated 17psi of pressure in the water system. Next, the block tester, ran the test, fluid stayed blue, didnt believe it, did it again, gassed the motor the works - stayed blue. So, assuming I did it right, there is no combustion gas in the coolant system either.
Anyways, sure that with less boost it had to run cooler I did the test runs again.
No improvement. WTF!
Anyway, at this point I had given up hope, started ringing around to get a 1HD-T transplant. Sadly, everyone I called told me I had no chance of getting a 1HD-T. Then of course there was the bloke who offered to rebuild my motor, using my turbo and put it back in for $12.5k!
So, I got my hands on a field service manual (you can find them on the web digitally). Found one more item in the list for overheating - injection timing retarded. Bought the SST from toyota ($175) and a dial guage ($75 at tool mart). Did the checks, determined the timing was retarded 10%. Adjusted it, (also put in a new air filter - should have checked first, the old one was labelled new just 10k ago) took it up the hill.
No improvement
Anyway, Im back to giving up now. This weekend Im picking up the viscous coupling goo and Im going to service the original fan clutch and reinstall, plus yank the spotties. I must admit, I dont hold much hope as I dont believe fans do anything at high speed (compared with the airflow you get from driving it) and the I dont understand why other people can run spotties and I cant.
Basically I bought the cruiser because I wanted a rock solid reliable machine, but at the moment I havent really been able to take the trips I want to because Im afraid im breaking it.
So.....
If anyone has any ideas Ive missed pleeeasssee fire away
But more importantly....
Can anyone recommend a really good deisel mechanic? I think im all out of ideas. Preferably near kewdale/welshpool but Im willing to go anywhere in perth with the right recommendation.
Thanks in advance.
Have wanted to get a 4wd for ages and last year I decided I had spent to longing sitting in the passenger seat while my mates were four wheel driving.
So in December I picked up a 91 1HZJ75 with aftermarket turbo. Took her down near augusta. Had a blast 4WDing around the forests there and did another run to Brunswick junction which was a bit more technically challenging. Absolutely loved it!
But....
On the run down to Augusta, and the return she overheated (went to 3/4 and didnt look like stopping till I backed off), could only manage about 95~100 safely. Also found it doesnt like hills, the hill up welshpool road to kalamunda does it every time. It doesnt overheat cruising the city and you can 4WD all day, even on the steep inclines at Brunswick and the needle doesnt move.
I had hoped to post something once I had figured out the solution as it seems to be a pretty common problem. I was toying with the concept of an intercooler until I went up the hill at night with 20 degrees ambient, it did the same thing as a 40 degree day - and I dont believe the intercooler will drop the intake temp by more than 20 degrees.
Anyway, I spent a fair while googling, and was excited to see that 1HZs without turbos do the same thing - so at this point I was pretty convinced it was the coolant system.
I replaced the thermostat (which is not easy to get to with the afermarket in the way) - it didnt do to well on the boiling water test but didnt seem that terrible. Recommendation to anyone going through this, its that hard to get to the thermostat and there only about $30 dont worry about testing it, just replace it, be careful with the gasket, mine slipped out a bit, pinched and I put the whole thing back together before I realised it was leaking
I replaced the fan belts and the viscous clutch ($175 at repco). The old clutch didnt really seem to bad. The old belts definately needed some tension.
No improvement
I had a new pump to put in($140 at repco), and here Id like to say a big thankyou for nothing to to the publisher of gregorys automotive manuals who didnt mention you need the timing belt off to do the water pump . Put it all back together again and picked up a new timing belt kit ($215 at repco - seeing I was going to take it apart anyway). Pulled it apart again, swapped out the pump, worth doing, the bearing was clicky. Succesfully rebuilt the timing belt and in the process realised the ******* I had bought it off had used silicon to seal the rocker cover where he had pinched the gasket once - down to repco - new gasket ($15 at repco).
No improvement
Amidst all this I had bought an infrared temperature gun from supercheaps ($30). Did some testing, found the radiator ran about 87deg at the top inlet and about 50~55 at the bottom outlet. Also, believe I can definately say the temperature guage is not faulty as when its reading 3/4 on the dash the temperature gun is showing 95deg at the top of the radiator and surprisingly about 87~90 at the bottom - couldnt really figure out what the high reading on the top meant but discounted the gague on the dash.
Time for a new radiator, picked one up at radiator wholesalers ($350). Went to put it in that weekend - it was the wrong one. To their credit they swapped me one out the next week. Replaced the radiator next weekend.
No improvement
I would have been tearing my hair out at this point but fortunately in parallell I had been working to install a boost guage. (I found a good example from a website on where to tap in and copied that - it came up really neat. Can provided instructions if required). On the run to my testing ground (the hill up welshpool road) I realised that the turbo was putting in 15psi of boost at 100kph. Bingo I thought - way too much boost.
Next weekend pulled out the wastegate, pressure tested it, it opens at 15psi. Couldnt really solve that then but decided to wind out the clevis on the end of it. Got the boost down to 5~6psi max at 100kph and about 7psi going up the hill.
NOTE : at this point I was already very paranoid about a cracked head, even though there were none of the signs (no bubbles in the radiator, no oil in the water, no water in the oil, expansion tank not overflowing). I bought a radiator leak tester($200 at coventries) and a block tester ($150 at coventrys). FYI the radiator leak tester is great, when I detected a 1psi drop over 1minute I traced it to a loose hose clip that only produced 1 single drop that didnt even drop off in that 2 minutes. Fixed that and it held pressure for half an hour. So, no leaks under rated 17psi of pressure in the water system. Next, the block tester, ran the test, fluid stayed blue, didnt believe it, did it again, gassed the motor the works - stayed blue. So, assuming I did it right, there is no combustion gas in the coolant system either.
Anyways, sure that with less boost it had to run cooler I did the test runs again.
No improvement. WTF!
Anyway, at this point I had given up hope, started ringing around to get a 1HD-T transplant. Sadly, everyone I called told me I had no chance of getting a 1HD-T. Then of course there was the bloke who offered to rebuild my motor, using my turbo and put it back in for $12.5k!
So, I got my hands on a field service manual (you can find them on the web digitally). Found one more item in the list for overheating - injection timing retarded. Bought the SST from toyota ($175) and a dial guage ($75 at tool mart). Did the checks, determined the timing was retarded 10%. Adjusted it, (also put in a new air filter - should have checked first, the old one was labelled new just 10k ago) took it up the hill.
No improvement
Anyway, Im back to giving up now. This weekend Im picking up the viscous coupling goo and Im going to service the original fan clutch and reinstall, plus yank the spotties. I must admit, I dont hold much hope as I dont believe fans do anything at high speed (compared with the airflow you get from driving it) and the I dont understand why other people can run spotties and I cant.
Basically I bought the cruiser because I wanted a rock solid reliable machine, but at the moment I havent really been able to take the trips I want to because Im afraid im breaking it.
So.....
If anyone has any ideas Ive missed pleeeasssee fire away
But more importantly....
Can anyone recommend a really good deisel mechanic? I think im all out of ideas. Preferably near kewdale/welshpool but Im willing to go anywhere in perth with the right recommendation.
Thanks in advance.
