1kd head gasket blew

[xliney Lurker Find all posts View Profile Close xliney]

Recently had a problem with my 120 1kd, drove all towing a Jayco, stopped at the info centre, on restart it was running rough, sounded like it was chuffing air out of the snorkel??? black smoke, white smoke, terrible noises. Cancel trip to national park, luckily a van park nearby. Call RACQ, can’t diagnose properly but thinking cracked piston. Workshop can’t look at it for a week, offered to tow us home under our ultimate care plan. Ok 600kms in a tow truck and my other half has a bad back… arranged tow for 2 days time and an early start. On the way out of town we pass a local the Toyota dealer??? What the? RACQ didn’t mention them as an alternate and I didn’t think to look. Anyway back home after dropping off at workshop for diagnosis I am reading all the pradopoint notes and googling and getting depressed that the Prado is going to need replacement engine No.2 !!! Car has done 360000 rebuilt engine 120000km. Workshop checks injectors and seals all seems fine, sent injectors for test, all test fine. Head scratching. Replace engine, buy used from wreckers, buy new from Toyoster, rebuild ?? Which way to go…
Online consensus seems to be do not spend money on finding out the pistons are cracked just fix. Local curious mechanic who has looked after the Prado deems it wants investigating further. To keep costs down he will work on it sporadically. Anyway head comes off and he calls me to come see …..blown head gasket between cylinders 2and 3. Pistons and bore look fine, oil clean, can’t locate any other problems, what was root cause?
send head off the be crack tested and machined. Report all looks ok. Machine head, replace all gaskets, new head bolts, new timing belt and tensioner ( to be sure even though they had only recently been done) new injector seals, clean, put back together, test run, 5 weeks later and $3500 lighter the Prado is on the road again, good as gold. Still none the wiser why the head gasket went though..thanks for reading, just thought I would share.

[ptommo59 Senior Member Find all posts View Profile Close ptommo59]

Great news that it wasn't as bad as you had initially thought and thanks for posting the update.

Did you take any photos? Would be interested to see what the top of the pistons and head gasket fail area looked like.

[JohnCW Lurker Find all posts View Profile Close JohnCW]

Mines a 1KZ-TE so may not be applicable, but I keep a VERY close eye on the temperature gauge when towing, especially up steep hills. If I floor the accelerator in low gears and have the engine spinning around the 3000+ rpm working hard the engine temperature starts to climb dramatically. However If I keep the revs between 2000 - 2500 the temperature may climb slightly but not alarmingly.

The speed difference up hill of those 500 revs in low gears at near full throttle is negligible, so my theory is from that extra fuel the engine is just producing extra heat. So basically I drive up hills watching the tacho (under 2500, closer to 2000 which is max torque) with a close eye on the temperature gauge.

[ptommo59 Senior Member Find all posts View Profile Close ptommo59]

Hi John,

I found the same and used the same technique with my 2012 1KD-FTV Hilux auto when towing a caravan near max towing capacity.

The trans cooler helped manage temps a bit but the controlled right foot worked even better.

When towing trying to maintain speed or accelerate uphill with foot flat to floor is a recipe for an overheated transmission and potentially a cracked piston on the vulnerable 1KD's.

[JohnCW Lurker Find all posts View Profile Close JohnCW]

Certainly a transmission cooler is a must have, at least on these older models. Prior to fitting mine, the transmission oil would be noticeably dark after a trip. I just changed the transmission sump the other day after a 10,000 Kilometre trip and the oil came out looking like new. Granted many of those K's were in SA and VIC where the temps were mild to cold. I change the 4 liters in the trans sump after every decent trip, my way of avoiding doing a full flush.

[kizbot Member Find all posts View Profile Close kizbot]

After fitting an EGT gauge to my 2010 Prado 1KD, I noticed the same thing when towing. Always worth running higher revs to keep things cool. Putting too much load on the engine will send the temps skyrocketing and I can only assume that puts added stress on those pistons. I'll run up around the 2500rpm to 3000rpm if climbing a decent hill with the caravan on the back. I wouldn't push revs over 3000rpm. When cruising in 4th gear, the revs sit around 2500rpm at 95km/h which in my opinion is on the high side for prolonged periods but the temps sure do stay down compared to going to 5th gear.

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

I haven't got EGT, but noticed using scangauge that the engine temp always climbs in 5th, even if it is under minimal load (based on live fuel consumption).