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Topic: !?I think my headgasket might be blown?! (Read 751 times) previous topic - next topic

!?I think my headgasket might be blown?!

I got this car, an 86 cougar 3.8 at, a couple of weeks ago. Its run a little hot since I got it. The needle usually sits just to the left side of the M. once or twice it has gone to the point of completely covering the M but would drop almost immediately to the point where the needle is almost verticle then work slowly back to the M. It has never hit the red zone in the time I have owned it. This morning on my ride to work it covered the M then started moving past it! I pulled over and let the car sit for 15 mins or so then finished the last 20 mins of my drive with the needle still covering the M. Now I know that the heater core leaks but I was under the impression I could put this off for a while. The water pump is not leaking from the weep hole and the coolant seems to move through the radiator ok. Yet when I got to work and popped the hood for a quick look-see I could hear the sound of water boiling off from the right (pass) side of the engine but could see no visible leaks from any of the hoses or connections. Leading me to believe its a bad HG. What do you all think? Am I screwed here. How bad is a HG job on these motors? Let me know. All comments appreciated.

!?I think my headgasket might be blown?!

Reply #1 –
symptoms of a blown headgasket:

periodic white smoke "could" mean the headgasket has a minor defect
Continuous white smoke means the headgasket is most likely to be blown.,,, Perfrom compression test

If your constantly adding water or coolant, the water is going somewhere outside the car, thus te white smoke or heater core. 
Loop back the heater core hoses up at the pass side of engine bay and retest over time.


in your situation,, you do have water boiling over so,, since you did not mention periods of white smoke being intermittant or continuous, My first thoughts are the fan clutch (40dollars).

Fan clutch is easy to install and you can DIY. 
to test with cold engine-  you wont be able to spin the fan one complete turn by hand with all your might.

to test while engine hot--- have car running, open hood, watch fan,, turn off car,,,, Fan should stop turning within a 1/2 to on full second after shutdown.
with a super hot motor, if the fan is real super easy to spin,, replace the clutch.

last but not least,, the thermostat,,,, which is the cheapest and quickest part to throw at it before moving into the areas above.

other areas to look at would be the flow of the radiator (coolant has corroded the flow tubes closing them off)
or
Transmission fluid is getting so hot, the secondary side of the radiator is transfering heat to the water. 


If you have'nt spent money on the car,, and its paid off,, and your insurance is so cheap you laugh all the way to the bank,, spend some money on the ole girl,, shes prob been good to you and 3 or so hundered bux in new piece parts would be a good idea.

a headgasket is toooooooooo easy.  But the general public thinks its time to freak out and jump off the empire state building.  Take your pick,, : )

Now,, get to work!!!:D

!?I think my headgasket might be blown?!

Reply #2 –
Well its definitely the HG :p  An external fail fail fortunately. It was making the hissing sound this morning but it now pumps a.f. out in a nice little stream from the right bank head. The worst is I think I caused this! The fan clutch is toast. Does not engage the fan at all. And here I was thinking it just ran hot because the system couldnt hold to pressure:hick: The oil is not milkshake yet and I see no indication of exhaust gasses in the a.f yet. I was foced to drive it home 40mi today with the thing g out and running hot. Tomarrow I'll pull the t-sat out and see if I can mount an electric fan to the radiator some how. Zip-ties or duct tape should work wonders! I have to be able to drive this thing till the weekend. My DD (Subaru Outback) is in the middle of an engine swap I started this past weekend because of a bad HG, and I dont think I'll have it ready any sooner than Friday. And I know HGs are not hard to replace but it gets pricey the moment you send your heads to the machine shop! So anyone have a decent 3.8 sitting in their garage from when they did a 5.0 swap? Willing to pick up within 150mi of Spfld Mass.
 

!?I think my headgasket might be blown?!

Reply #3 –
wow

the thing about sending off the heads might not be a bad idea.

the warpage allowance on those heads is .006 diagonally.  I tolerate zero.  I just sat the head down on my big ass belt sander and let it zip away.  When you flip it over you can see where the belt is removing metal and where it isnt.  when you finally see metal being cut away close to the center of the head, then stop. 

anyway,,,, forget about the electric fan thing,, first off, ill bet you forget to mount it in such a way that it does not NULL out by forward motion of your car,,,,,,,,,:D :D :D 
just kidding but there was a guy on here a few years ago named "JOE FRIDAY" who fiddle fugged his way into the same problem. finally realized why things were getting hot while moving and cool while sitting in traffic.  An exact opposite of what you would expect on an over heating engine.

just get er done,, you know what needs replaced.  let us know how you make out,, the HG kit aint that bad in price.  Dont forget new head bolts since these are tty.