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Blown Head Gasket? coil pack? Coolant? Radiator?


HKSTurboRacer

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Hi.

I am new to the forum. I have a 93 TT auto Jap import.

I will explain in detail as much as i can as to what i have been experiencing. I am a newbie to cars but I have learnt a lot recently and continue to gain knowledge and experience. I really need your help as i am very stressed with my Supra lately. Any help will be appreciated. sorry for the long post i have a few issues but can be all inter related.

 

So everything was fine with my car apart from issues with starting the car up (i would have to jump start it, i tested my battery and alternator with a multimeter and they are fine) I went to fill up and drove the car hard there and back. 5 days later (16th June) i started the car and drove few miles. When i got back in the car to drive back home after starting the car the exhaust sound was deep for around 5 seconds and then went normal like it opened back up. Very strange first time this ever happened. Got home and then i headed back out. This time i reversed out the driveway and car jerked a little. It also did not sound normal almost like its misfiring. I then left from that place to come back home and on starting the car it would shake/vibrate. Then on the 24th June i thought let me take the car for a spin around the block to see how it behaves since my last experience. The car lacked power! acceleration was poor, gear changes were fine and sounded ok but was just was sluggish like its holding back power.

 

Ever since that day (June 24th) i did not drive until the 5th July i decided to take the car to the garage to get it looked at. On the road just before the garage i decided to turn the AC on (it was a hot day!) i noticed my temperature gauge go up to 3 quarters of the way. I pulled in to the garage and turned the car off immediately. Told the mechanic and he said water/coolant must be low which it was. Basically took a whole gallon of water. I noticed the sound of the engine and exhaust went quiet. Almost as it has calmed down and back to how it normally should be sounding. I checked the water level in the radiator a few weeks prior and it was full. So it must have leaked or where else would it have gone? after leaving the garage i stopped at a auto part shop which done the free battery test for me. While doing the battery test even he noticed how hot my engine bay is and confirmed my battery is good, can do with a charge but seems fine. He did not have a alternator tester. Anyway so on my way home the car was pulling good, better acceleration and power. I decided to turn the AC on again and the needle started going up back to 3 quarters high. I quickly turned the AC off and it slowly came back down to the middle.

 

Now the very next day thinking my car wont start as its got a mind of its own (intermittent starting) it started and i went to my friends house who had a multimeter to further test the battery/ alternator which were fine. While my car is idling it is idling rough, like it is misfiring and the exhaust/car in general vibrating. After some driving i noticed the car in traffic was jerking at low speed coming to a stop and the rpm was very low like the car is about to stall. white smoke occasionally would come out but i also have a valve stem problem which needs replacing (well that is what i was told by who i purchased the car off. he gave me brand new stem seals with the car) and i think that is related to that. After reaching home and an hour and a half later i decided to top the radiator with water and it took a few jugs! The engine bay and hose pipes were VERY HOT. Car would not start. Very loud thump sounds trying to start the car. I had to push it to and onto my driveway!

 

10 days later today without the car being started i decided to check the water level in the radiator. It took a lot of water considering it was sat and not started or driven. Therefore i decided there must be a leak of course. Hoping its just a hose which i can replace and then flush the radiator and have fresh coolant. so i jacked the car up and checked the hoses which all seem fine not cracks or tears apart from the small hose on the bottom end which seems easy to turn but again no leak. Upon starting the car the exhaust shoots out some water and i noticed from the rusty radiator the exhaust had that same rusty water. You can see it in the exhaust. car sounded awful. I had a friend go underneath and he assumed the water is leaking from the top somewhere as he said a lot of water dripped down. So we undone the radiator bolts and the fan shroud to pull the radiator up thinking there is a leak in the radiator. We started the car and there was no leak anywhere. i was expecting water to pour out of a hole in the radiator but nothing! then i said lets check the engine oil. we opened the cap and can see a little water in there. its also is on the dipstick started to get milky. i only started the car and moved it to another spot on my drive way. checked water and had to top it up again. after starting engine topped it up again. so where is the water going! no way i can drive the car even to the garage. needs to be towed.

 

Me and my friend have come to a conclusion that it can be a blown cylinder head gasket. What does not make sense is it over heated approx 3 times going 3 quarters not in the red or near so why would it blow the head gasket. Also if there was a leak where was it leaking or was it going in the engine? as some water is coming out the exhaust also. I do think the coolant was low or none in there just water and due to the hot weather it took a toll and i left the radiator flush late to where it has now starting mixing with the engine oil...passing the head gasket and going in the engine? if i done the radiator flush earlier if i knew and put toyota red in it would of been fine that is if it never leaked.

 

If its head gasket it will just need to get replaced with radiator and engine oil flush right?

If its not got to that stage what would you advise? i was thinking to do a radiator flush today but it may be a waste of time as water is dissappreaing and i do not want to start the engine any more to cause more damage. what do i do?!! please someone help!

 

To summarise and Conclude:

starting issues -

not the battery or alternator

Can not be the starter as it starts with jump leads or starts randomly when it wants.

Can be coil packs as car struggles to start but also is running rich and felt like its going to stall (low rpm)

Or is it radiator/head gasket related?

 

radiator/coolant/head gasket related:

with AC on car temp spikes

Car in general gets hot and temp is going up now regardless

water is dissapearing from radiator maybe going into engine oil and not a leak?

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I'd have the compression checked ASAP on the 6 cylinders to see if they are all consistent, that'll check out any head problems for you either with the head itself, gasket or valves. There is no reason to loose water other than a leak which you say you don't appear to have or as steam out of the exhaust. If the water was going into the engine sump then you'd expect to see it in the oil and as an emulsion on the valve gear. It'll only take you half an hour to an hour to check the cylinder pressures and then move on from there.

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I'd have the compression checked ASAP on the 6 cylinders to see if they are all consistent, that'll check out any head problems for you either with the head itself, gasket or valves. There is no reason to loose water other than a leak which you say you don't appear to have or as steam out of the exhaust. If the water was going into the engine sump then you'd expect to see it in the oil and as an emulsion on the valve gear. It'll only take you half an hour to an hour to check the cylinder pressures and then move on from there.

 

Thanks for your reply. This is what i have been advised by my local mechanic. I believe water has now got into the oil mixing. I have some pictures.

IMG-20180717-WA0010.jpg

IMG-20180717-WA0007.jpg

IMG-20180717-WA0008.jpg

IMG-20180717-WA0005.jpg

IMG-20180717-WA0006.jpg

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This looks serious :( in hindsight posting up in the first instance may have helped.

 

I'm no expert but the absolute best you can hope for is it's a 'simple' head gasket to get you back on the road, but loads of other potential (probably but I'm trying to be optimistic!) issues, not least why it happen (the overheating) in the first place as the head gasket just going is not normal.

 

Might be time to brace yourself (financially) and off load it to one of the forum guru's to assess?

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Don't drive it! As mentioned leakdown test ideally. Then go from there. Looks like at best the head needs to come off for further assessment. An oil and water mix doesn't do any good for the bearing surfaces in the engine though either..

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If you had to put a gallon of water in it then its lost approx half of what the coolant system holds which

on the auto is 8.8 litres

 

You'll need to find the reason why its overheated first, blocked rad, rad cap not working correctly, thermostat

not opening correctly, does it have an expansion tank fitted.

 

Before fitting a new head gasket the head will need to be checked to see how flat it is

Edited by Dnk (see edit history)
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If it is coolant loss into the cylinders be very aware that this will cause bore and piston ring corrosion. The way to defer this is to drain all water out and then run the engine at a fast idle for 3 minutes. This will dry out the bores and in theory no more coolant can migrate in. To be more sure you can then remove all spark plugs and put two tablespoons of engine oil down each plug hole and spin over on the starter for a few seconds. Reinsert and tighten the plugs, this will give protection until water is added again or you can resolve the situation. A sniffer test using a gas analyser like used for the MOT or a dye test will likely show if head gasket failure has occurred. I can do either, some MOT stations are coy about alternative uses for their 4 gas analysers...

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Apart from the obvious that coolant and oil has mixed. Rusty water vapour coming out the exhaust usually means internal terminal damage. Wish is it wasnt true in this case mate

 

 

That may not be the case at all if suitable precautions are taken in a timely manner, like *NOW* :) Leaving water in the bores for days will likely give serious issues though. if the coolant has a good dose of antifreeze in it the corrosion inhibitors in it will help greatly until it's drained as above.

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That may not be the case at all if suitable precautions are taken in a timely manner, like *NOW* :) Leaving water in the bores for days will likely give serious issues though. if the coolant has a good dose of antifreeze in it the corrosion inhibitors in it will help greatly until it's drained as above.

 

But from what hes said it has been a fair time for any rust to start inside, thus rusty water in the system. Im fairly sure a head gasket change, oil and coolant change may not cut this one in the long run. And if its gotten that hot to blow the head gasket id be worrying more about cracks to the head.

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It doesn't look good unfortunately, hopefully its just a blow gasket causing the issues. Beyond that there is a lot of rust in the coolant, with these iron blocks people really should go waterless coolant or do the recommended change every 2 years as inhibitors do age degrade.

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Hi guys. Sorry for the late reply had issues logging in.

Just an update. I had a cylinder leakage test done today and cylinder 4 has water inside. Also spark plugs were wet and need replacing. so therefore it is a blown head gasket.

How much should a head gasket replacement cost labour /parts? The garage near me who done the cylinder leakage test first said 700 just labour. Then spoke to his mate who said its a big job and he said roughly may be 1300/1400 but will confirm..so he doubled. Then said 2k with parts included apart from new spark plugs and timing belt (recommend changing and i was thinking to anyway as labour is included) he is over pricing me for sure although hes work is professional. Can any1 tell me what do you think? Also how much i should be looking at?

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You need to find out how warped the cylinder head surface is and go from there... Toyota have tolerances set in the TSRM where if the head is warped more than 0.10mm Toyota deem it to be scrap....

The other thing you want to know is why this has happened, you say the gauge went to 3/4, well IMO this wouldnt cause the issue you have now, more likely it could be as a result of. More investigation needed I would say and perhaps someone who is experienced with Supras would be the best idea. While it is only a straight 6 engine at the end of the day, a good 2jz mechanic could save you a load of dosh at this point.

Edited by and1c (see edit history)
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The 3 most critical concerns once the head is off is how warped it is, and in particular, how much have the cam bearing saddles moved? Whilst you COULD have the caps dropped and be line bored it would cost more than a good used head, maybe even more than a new casting. The other deciding factor is has the head got hot enough for the alloy to have softened? I have three heads here which have all gone soft and failed a Brinell hardness test. Finally, head wise, check all waterway openings for corrosion that may have opened them up beyond the head gasket coverage. Running with anti freeze with its inbuilt corrosion inhibitors can quickly erode the waterways in the head. The 2JZ head gaskets can fail in an unusual way and if they don't know what to look for the may think it's OK.

 

You must also check the head face of the engine block to see if that too has warped. Nothing here is unique to this engine, just normal competent practice if an engine has suffered head gasket failure.

 

 

If they just slap a new gasket on you may well find it fails again.

 

Whilst the head is off now is a good time to have the guides and valve seats done....

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The 3 most critical concerns once the head is off is how warped it is, and in particular, how much have the cam bearing saddles moved? Whilst you COULD have the caps dropped and be line bored it would cost more than a good used head, maybe even more than a new casting. The other deciding factor is has the head got hot enough for the alloy to have softened? I have three heads here which have all gone soft and failed a Brinell hardness test. Finally, head wise, check all waterway openings for corrosion that may have opened them up beyond the head gasket coverage. Running with anti freeze with its inbuilt corrosion inhibitors can quickly erode the waterways in the head. The 2JZ head gaskets can fail in an unusual way and if they don't know what to look for the may think it's OK.

 

You must also check the head face of the engine block to see if that too has warped. Nothing here is unique to this engine, just normal competent practice if an engine has suffered head gasket failure.

 

 

If they just slap a new gasket on you may well find it fails again.

 

Whilst the head is off now is a good time to have the guides and valve seats done....

 

Great info Chris. Curious at to why the cam bearing saddles would move? Due to the heat generated?

 

To the OP - Maybe just take it to Chris if you want it done right!

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Just think of the head as a rectangular block of aluminium alloy. Bottom face should be dead flat. Top face is machined with "semi circles" for the cams to sit in and turn, with bolted on caps to allow the cams removal. If the bottom face warps almost certainly the top does too, taking the once perfectly straight and true alignment of the cam bearings out of kilter with it. A cast chilled iron cam doesn't take kindly to be pulled banana shaped then rotated rapidly! If it doesn't break it will wear the journals in the head and itself to become free again, leading to greatly enlarged clearances, abrasive alloy powder in the oil (fine enough to pass through an oil filter) and loss of oil pressure due to excessive cam to cam journal bore clearances.

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I suppose the good news is if you are only shipping water into one cylinder then its very unlikely there is any cracked block damage. I did try once on an old Ford Essex V6 in my Capri of the time to just change a failed head gasket and hope that'd fix it because that car was my only car, the daily driver but nope had to get the head off again the next weekend and off for skimming. So it is definitely worth getting the head all checked out before reassembly even if it means losing the car for a week or so and while its off as Chris says its a no brainer to get the valves checked over and stem seals done at the same time.

 

I fear your wallet is about to get seriously assaulted.

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Just think of the head as a rectangular block of aluminium alloy. Bottom face should be dead flat. Top face is machined with "semi circles" for the cams to sit in and turn, with bolted on caps to allow the cams removal. If the bottom face warps almost certainly the top does too, taking the once perfectly straight and true alignment of the cam bearings out of kilter with it. A cast chilled iron cam doesn't take kindly to be pulled banana shaped then rotated rapidly! If it doesn't break it will wear the journals in the head and itself to become free again, leading to greatly enlarged clearances, abrasive alloy powder in the oil (fine enough to pass through an oil filter) and loss of oil pressure due to excessive cam to cam journal bore clearances.

 

Very good point!!

Yeesh

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