need some detailed tech questions

[GAME OVER]

hey guys, first of all i just bought a 89 turbo and like all peeps scattered here, im wondering so much about the ins and outs of a supra.

ive been researching some facts about my supra and found out that it has a serious flaw with regards to its head gasket. im planning to mod this and join the 400 hp club but more over than not, reliability here is my priority. it wouldnt hurt to make sure if my beast is fit enough to that label.



how would i find out if my hg is blown??? :huh: too much redunduncy on this topic but no specifics whatsoever....
what other parts do i need to replace other than the hg itself and the arps boltswhile im havin it done????
id rather buy whatever i need beforehand and have them all done at the same time
how much would it normally cost to have it replaced???
anybody ever compared dealer quotes from the outside perf shops quotes???


right now the car runs decent but you can see traces of oil smudges all over the lower parts of the engine bay...im thinking of having it steamcleaned soon to get rid of the oil

i think my 93 na z32 runs faster than my supra even with its turbo working
maybe its me but i just me but i think that the reaction of the car is slow(yes i know, my car is the supra's nemesis but hey im not being biased here. we all have the need for speed)

mods cost a fortune and so does some engine work so we only need to do all of this with one pass.



any info's would be appreciated

-edz
(12 am stalker)

:huh: :huh: :huh:

[suprra_girl]

hey

easy ways to check if your hg is gone... do a compression check.. let us know your numbers they should be 142 or above.. make sure they are even and don't differ by more than 14psi between cylinders
if you compression check comes up good you can next try a block check and see if there are exhaust gasses in the water

other than those tests there are just the usual tell tale signs, water bubbling out the overflow, overheating or spiking of the temp gauge

i can't think of any others off the top of my head right now

let us know how you get on

[GAME OVER]

hey there

thanks for the reply, the compression test will be done on thursday by a mech friend of mine
hopefully the numbers come up good. also, since you mentioned a block test... how is that done?(total newbie here sorry) would it require removal of the engine???

cleaned up the engine with degreaser today... if it was only possible id clean the whole thing with a toothbrush... still waiting for some signs of oil leaks whatsoever.

im gonna hang around for a while to see what i can learn from you guys if you dont mind

cheers....

-edz

[suprra_girl]

cool so that's the compression side of things taken care of

and no a block check doesn't require removal of the engine hehe
it's a rocket shaped tube which has a rubber bung on the end, you fill it with special type of fluid and shove it in the top of your radiator while the car is running to see if there are exhaust gasses in the water.... generally the fluid colour is blue and if exhaust gasses are present it will change to green or yellow usually fairly quickly

hehe i know bout the toothbrush thing... i cleaned this one for 2 days with one :P




glad to have ya around

I keep seeing the same answer to check a bad head gasket is a compression check. I may not be ase certified but I do know that a compression check should only be used to decide if a engine is rebuildable. If you would like more detail about your engines condition and cover the major areas use a leak down test. Doing this is easier than it sounds. Buy a adapter from any auto parts store (+/- $20)that threds into your spark plug hole and connect it to a compressor. Rotate engine to move each cylinder your testing, to top dead center. "Intake and exhaust valves closed and pistion up, for lamens" Lock engine still or SLOWLY (OR ENGINE MAY ROTATE WHEN YOU DONT WANT IT TO) increase air pressure to about 90 psi. Not confusing "sea-shell" sounds from air leakage listen for air leakage. Disconnecting intake and opening throttle valve to listen or even feel air coming out could test for intake valve seating problems or bad valve timing, listining to tail pipe or feeling air rushing from tail pipe can tell you you have again bad valve timing or burnt /bent exhaust valve, remove the oil cap and you will hear a little of usuall blow-by, this one you have to realy listen and compare each cylinders air flow one may be a little louder or feel more air coming out could be bad compression rings, and the biggy for the 7mge is the head gasket test, before inserting the air into the chambers remove the radiator cap "only when cold of coarse", top the radiator off "I only suggest distiled water" anyway Slowly release the 90 psi into the cylinder and once there watch for spitting water from radiator "a bad leak" or look inside radiator for any signs of bubbles, bubbes there is a deffinate sign of a bad head gasket. If looking into buying a car and cant perform this test, a good way to tell is the coolant reserve tank. A good engine that has never had a blown head will have a clean white overflow tank, one that has blown, may be yellowed or dingy, looking inside maybe even a prominate line of dingy yellow from oil in the water or cooked fluids. This is commanly over looked by private sellers or dealers trying to armor-all a car just to sell it. Also i may not have spelled all this right, but try it, youll be suprised how much this is used by shops and how much it can tell you.

[suprra_girl]

there are many ways a head gasket can blow, the use of a compression tester is used in the case of the cylinders leaking between each other i.e one cylinder will read very low because the compression is leaking into another cylinder, it's an easy way to diagnose one variation of blown head gasket.

and the part with seeing if your leak down test for detecting a leak into the water system, hence why we use block checks, run the car up to operating temp so that the thermostat opens and bung it in... alot easier in my book but then some ppl do prefer your way of doing things as well

and can you please break up your posts as they're very hard to read when they're all together