head gasket may be starting?
BobbyisKing
02-12-2004, 12:00 AM
89 supra turbo, i just checked the oil filler cap this afternoon and saw a light brown liquid on the cap, which i konw is a sign of a blown head gasket. The radiator water in the overflow bottle has a swirly different color in it also. The low radiator water light came on yesterday, and i filled it up today, so im pretty sure that the head gasket is beginning to fail. Will tightening it up again stop it? i pretty sure it wont but i hope it will. whats the best thing for me to do? sorry if this has been asked before, its just that i know if the head is blown for sure, repair and replace, but the car isnt over heating. thanks for listening
projectsupramk3
02-12-2004, 11:09 AM
Yea that's what it means, I was going to say something about the dissapearing coolant in your other post but oh well. So you've already retorqued the head bolts? If your already showing signs of BHG it won't help any cause the gasket is already decentigrating and deformed too much. How much is it puffing out smoke as of now? You can drive it if you have to right now but the best thing to do would be to just tear it down now before something else gets messed up. It'll mean less machine work and less money spent to rebuild it in the end.
BobbyisKing
02-12-2004, 11:58 AM
my dads already really mad because we had to take it to the shop twice already, and i have to drive it. i don't think the shop retorqued the head. If i was to tear it down right now, since it isn't completely blown yet, would swapping in a new head gasket be allright? do u think the engine is deformed or anything yet? hopefully not. o also, what is the lights on top of the abs and engine check lights? those and the break lights came on yesterday when i started the engine, but when i reverse, they dissapear. any thought of this? thanks for listening.
xjoeharperx
02-12-2004, 12:26 PM
swapping the gasket is fine providing you havent overheated the motor..dont forget to follow the torquing procedure..
projectsupramk3
02-12-2004, 01:29 PM
Swapping the gasket with a toyota compsite yes, but if you want a MHG you'll need to have it checked out by a trustworthy machine shop and possably prepped/milled depending on the condition. Since you've got a turbo I'd go ahead and do the MHG/ARP's cause one day you will want more power, and this way the car will be prepared for it, alittle more work now will save alot of headache later. The only lights about the check engine light is the door open and the tail lamp failure, either you've got a bad ground or the yellow box is shorting out. It's nothing big as the taillights work the same, you just have to put up with the idiot light.
BobbyisKing
02-12-2004, 05:29 PM
i don't think i'll be boosting much so, i might go with the regular toyota headgasket. Would the 1.2 hks bead headgasket fit in without machining the head, i dont think so as i think it will raise the compression or something, because im kinda low on money. Ill have to wait a month until i get my money to fix it. Do you think casual driving around town will make mess up the head even more, as i need the car for school and shit. as for the lights, i was driving this morning, the brake light, the tail lamp failure light, and the battery light was flashing a few times. what does this mean? thanks for listening and for any responses
xjoeharperx
02-12-2004, 05:47 PM
driving the car with a leaking intake gasket might not be the best idea for you...if water leaks into the cylinder, when you crank it up you take a good chance on bending the valves...not to mention the damage from overheating and warping the head....if you get down to it and work diligently you should be able to do the gasket swap in one day, get at buddy to lend you a third hand and read the book before starting the job...a little hard work on saturday will keep you from walking some extra miles on monday...I know money is tight but better to do it now than kill the motor..
projectsupramk3
02-12-2004, 06:21 PM
Leaking head gasket... and I doubt you'd ever bend the valves, its very hard to do unless the cylinder is filled to the top with water and theres some foreign object in there, and then it's much more likely a rod or rods would bend, not to mention the 7m is a non-interferance engine. Like I said you can drive it if you have to, but just remember the more you drive it the worse the BHG gets. Also just get a 1.2 MHG, the different thicknesses are to compensate for how much you have shaved off the head (which will have to be done if you do a MHG unless its almost perfect and then you might get away with lapping the head), but it's such a minute compression change you would never feel a seat of the pants differance. There have been so many BHG walk throughs its not even funny, just search supraforums for it and you'll see what I mean. About the lights, if the battery discharge light is coming on then it could be 2 things, either your alternator is going out, or you have a loose alternator or ground cable/wires. If you want to test the alt take it to autozone or advanced and I believe they do it for free.
DaMoNe6969
02-20-2004, 07:00 PM
I would really recommend not driving the car at all until you get the BHG repaired.. There is more to it then the BHG just getting worse..
After the head gasket has failed, a combustion leak
leads to immediate destroying of the inhibitors in the coolant, and will
set up an acid condition in the cooling system. The acidic coolant will then
conduct electricity, and a galvanizing reaction will begin among the
various kinds of metals in the cooling system. This will eat away at the
radiator and other parts of the system from the inside out. When the
coolant enters the cylinders the result is a poorly running engine, cutting
engine life with each revolution as the coolant breaks down the engine's
lubricants. Combustion leaks in the compression ring area also force coolant
away during acceleration causing excessive heat. When acceleration stops,
the diverted coolant rushes back to the area, resulting in rapid temperature
changes. This is bad enough, but the compression leak also causes the
engine to blow the coolant out of the radiator and cylinder head into the
overflow reservoir bottle, depleting the coolant, causing the engine to
badly overheat. This heat further aggravates the already devastating
conditions in the engine by causing the metal alloy in the cylinder head to
expand, stretching the head bolts and further compressing the bad head
gasket.
After the engine cools down the head bolt tension due to the heat expansion
is relieved, leaving what is left of the original head bolt tension from
the torque up at the factory. Due to the mashed head gasket, internal
surface damage, and warped cylinder head, the factory bolt elongation is
all but used up.
After the head gasket has failed, a combustion leak
leads to immediate destroying of the inhibitors in the coolant, and will
set up an acid condition in the cooling system. The acidic coolant will then
conduct electricity, and a galvanizing reaction will begin among the
various kinds of metals in the cooling system. This will eat away at the
radiator and other parts of the system from the inside out. When the
coolant enters the cylinders the result is a poorly running engine, cutting
engine life with each revolution as the coolant breaks down the engine's
lubricants. Combustion leaks in the compression ring area also force coolant
away during acceleration causing excessive heat. When acceleration stops,
the diverted coolant rushes back to the area, resulting in rapid temperature
changes. This is bad enough, but the compression leak also causes the
engine to blow the coolant out of the radiator and cylinder head into the
overflow reservoir bottle, depleting the coolant, causing the engine to
badly overheat. This heat further aggravates the already devastating
conditions in the engine by causing the metal alloy in the cylinder head to
expand, stretching the head bolts and further compressing the bad head
gasket.
After the engine cools down the head bolt tension due to the heat expansion
is relieved, leaving what is left of the original head bolt tension from
the torque up at the factory. Due to the mashed head gasket, internal
surface damage, and warped cylinder head, the factory bolt elongation is
all but used up.
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