Question about 1998 Ford Mustang

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Compression for 1998 Mustang

How many pounds of compression should I have on a 1998 3.8 liter Mustang engine. I may have blown a head gasket as it got hot and there is water in the oil pan.

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  • otto13 Jun 24, 2008

    I tested the pressure today and one head's cylinders were 165,165,165. The other was 172.5, 172.5, 175. Based your your advice I need to look for another problem. What would be your thought. The engine has 101,000 miles.

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You may also want to do a simple check to see it the cooling system is holding pressure. You can use a tool or have a mechanic pressure up your system to check it it holds presure. Also after reaching operating temp, check the radiator cap after 20-30 minutes to see if it is holding pressure. I have also seen in the past a failed water pump. If the weep hole is plugged and the seals are out of the pump, coolant could leak into the crank case.

Posted on Jun 27, 2008

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Depends on condition of engine.What you want to look for is a large difference between related cyls. If all are with in 10-15 percent of each other your problem may be some where else.

Posted on Jun 23, 2008

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These are general procedures for tests so that you can see if your mechanic has actually performed them or not. If you want to run the tests yourself, I can give you more specific instructions.

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Head Gasket - need to remove the head and check the head and block for cracks. Then replace the gasket and reinstall the head.
Bad Valve(s) - need to remove the head and have the bad valves reground or replaced by a machine shop and then reinstall the head.
Bad Rings/Cylinder - the engine will need to be removed and either machined and rebuilt or replaced.

Again, if you want any more specifics, please ask.

Hope this was helpful!

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28 Solutions for ''HOw can I tell if I have a cracked head blown head gasket or cracked blown like how can I see it''


Often (but not always), a blown head gasket will also cause deposit of water on a piece of cardboard held an inch from the tailpipe output while the engine is running (when this is happening, it is likely that the catalytic converter has been ruined and the muffler will corrode in short order as well).

Sometimes drops of water will be seen dropping from the end of the tailpipe. Another clue: turn on the heater; often when the head gasket is blown an odor of antifreeze and synthetic rubber will emanate from the heater vents.
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