weird sounds when car moves

[Donovan]

ok well i own a 1987 toyota supra turbo 5 spd well when i drive the vehicle like almost every single ime when i start it right up and when i come from a stop and start moving there is this weird sound coming from it seems like under the car it sounds like a clacking sound with something hitting together like a rub with grinding and one more problem i am having is that when i purchased the car i could smell antifreeze but the guy said the smell was coming from the over flow tank that fills up with the antifreeze cause it does not have a seal on it to hold the lid on to the top of it so it always falls off but the rubber tube stays inside the housing of the resivore but its just doesnt let the cap seal shut could that be where i am getting the antifreeze smell from or dont tell me but could it be that my car is geting close to a BHG!!?

[cre]

The smell of coolant (in the engine bay) is typically from a leak onto the engine block or exhaust manifold. Pressurize the system to check for leaks.

The noise could be one thing or a combination of things, Check the carrier bearing (in the middle of the drive shaft) for play, the differential, brake calipers (one may be sticking), ball joints, and lastly have the wheel bearings checked.

The TSRM covers the troubleshooting of many common issues:
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/

[f00g00]

U joints or center baering on the drive shaft. If there is a thumping when you step on the gas while initially accelerating then the rubber has broken in the bearing and its flopping around. If not then you can get under the car if your arms arent long enough and grab the drive shaft and check the movement. A little play is normal, a lot means probably the U Joints are bad which will make noise when initially starting from a stop.

[Donovan]

alright thanks ill make sure to check that out this afternoon when i get home thanks

[Donovan]

okay this morning i got under the car and tried to move the driveshaft around but it did not really move at all or i dint notice it moving so im assuming that that is fine but i will still check the other stuff qwhen i get home but how do you perform a compression test on the block?

[f00g00]

Get a compression tester and remove one spark plug at a time, screw in the tester and crank the motor till the guage max's out, with the coil wire off of course.
Not really hard just a little time consuming doing all 6 then putting the intake back together. You will need to remove it to get to the middle plugs.

[Donovan]

ok i think i know what your tlking about i think i did this in autoshop but its a gauge like a psi and it tells you the pressure of the cylinders correct? but how will this tell me if there is a crack in the block or a bhg?

[supramacist]

You'll have low compression in specific cylinders.

[Donovan]

alright thanks um does anyone know what the compression would usually be in the cylinders?

[IHateHacks]

Mine were around 180psi. Whatever they are, you should be more concerned about the difference between cylinders than the actual number.

I ran a comp test when the engine had a blown head gasket and none of them were low, all around 180. A block tester will tell you definately if you have a blown head gasket or not.