Possibly A Blown Head Gasket

Posted in Ignition Systems
  • I have a 1997 mercury grand marquis and supposedly I might have a blown head gasket. I took my vehicle to pep boys for an inspection of the problem. They claimed their was no compression in cylinders 7 and 8 (misfire) and that it might be a possible head gasket / head and that they couldnt tell for sure. Another local mechanic said it could be the distributor / pack where (spark plug wiring connects) What should I do and how much do these repair run up to for a car such as the gran marquis?—> Notable symptoms: Muffler releases gray smoke but now it appears to be bluish gray. Lack of performance. At times the vehicle may stop when going uphill or going very slow.

    There are 5 Answers for "Possibly A Blown Head Gasket"

    1. dr martin says:

      if your head gasket has gone you need to check the dip stick. if the gasket has gone you will have water in the oil.the only way to fix this problem is to have head gasket fixed.dont drive the car as this will cause moor problems. you will need to have the head skimmed as well as it may have a hair line crack that is invisable to the eye. could cost a lot of money.

    2. Michael says:

      The worrisome condition is the reported lack of compression. It isn’t clear from the pictures in the source whether it is true for your engine, but normally cylinders 7 and 8 are in opposite banks. If so that argues against a failed head gasket, in which a common failure is a blowout between two adjacent cylinders. If the compression is actually bad, ignition fixes won’t help.

      If you do have two adjacent cylinders with low compression a cylinder head gasket failure of that type is confirmed by doing a leak-down test and seeing if there is air coming from the adjacent cylinder when the first one is pressurized.

      If the lack of compression is confirmed and the indications don’t point to a head gasket, the next step is to remove the valve cover and do a visual inspection of the valve operation as the engine is cranked. Some engines are prone to sticky valves and it is possible there is something out of whack otherwise.

      If the head gaskets are bad, replacement would be around $1100 to $1400. You can put your own location in the second source for a more accurate range. Almost any valve repair (beyond adjustment or lifter replacement) will cost slightly more – same labor and parts but added machine shop charges. Figure a couple hundred more.

    3. Daniel D says:

      on Fords cylinders 7&8 are side by side. If the compression is low with the first compression test they should of done a wet compression test then a cylinder leakdown test. the sylinder leakdown test will inject air into the cylinder and you should find it coming out one of four places. The Intake which would mean a intake valve is open, the exhaust which would mean you are losing compression out the exhaust, or it could be coming out the dip stick which would be causes by bad rings or craked pistons, but if its the head gasket it can also come out the radiator..so take the cap off and see if you can find bubbles

    4. bandit_60 says:

      it don,t have to be a blown head gasket. other stuff can cause no compression too like a broken compression ring or a valve can cause it.

    5. D.C. says:

      FORGET ALL THE OTHER WANT-A-BE MECHANIC ANSWERS —-THE WAY TO SEE IF YOU HAVE A BLOWN HEAD GASKET IS THIS —SINCE # 7 & 8 ON A FORD V-8 ARE THE BACK TWO CYLINDERS ON THE PASSENGER BANK OF THE ENGINE——PULL THOSE PLUGS OUT AND WITH A ADAPTER TO PRESSURIZE A CYLINDER TO CHANGE VALVE SPRINGS WITH THE HEAD ON——-HOOK UP TO A AIR COMPRESSOR AND ROTATE THE ENGINE TILL THE CYLINDER YOU PUT AIR INTO HAS ITS PISTON AT TOP DEAD CENTER ( TDC )——YOU HAVE TO TURN THE ENGINE OVER BEFORE YOU HOOK UP THE AIR —-IF YOU CAN NOT GET THE ENGINE TO STAY AT TDC THEN BACK OF THE ROCKER ARM NUT UNTIL LOOSE —-IF YOU HAVE A BLOWN HEAD-GASKET ( CALLED A CROSS-FIRE IN YOUR CASE ) THEN AIR WILL COME OUT THE OTHER SPARKPLUG HOLE——IN A CROSS-FIRE BLOWN HEAD-GASKET YOU USUALLY WON’T HAVE WATER IN THE OIL OR AIR COMING OUT OF THE RADIATOR —-AS FAR AS COST —IT CAN BE AS CHEAP AS $ 100 WITH A FRIEND DOING THE WORK UP TO A GRAND IF YOU TAKE IT TO THE WRONG PLACE