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Thread ID: 141399 2015-12-12 19:22:00 Mazda Capella engine. tut (12033) PC World Chat
Post ID Timestamp Content User
1412683 2015-12-12 19:22:00 Hi Folks.
I have this 1995 Mazda that I bought with supposedly a blown head gasket.
The previous owner had replaced the radiator which had split and when I took the intake manifold off I found a frost plug had come out. ( It was obvious that it hadn't been fitted properly )
When I first got the car home several months ago it turned over on the starter but had no compression then.
The head gasket has now been replaced and the engine put back together again.

Still has absolutely no compression on any of the four cylinders.

The engine was full of water when opened up and this has now been rectified.
It may have been overheated.
It may have been seized.

Without going through all the things that have been checked up to now, would some one like to put in their cents worth as to what they think the problem might be.
Maybe I might have missed something.
Have consulted with many experienced mechanics, gone through several Mazda forums and tried all the suggestions.

Many thanks to anyone that might find the time to add any comments.

tut
tut (12033)
1412684 2015-12-12 20:26:00 I wonder if he bores have been checked for roundness and the rings replaced? If so there most probably is a major leak in the upper regions of the head. Has the head been planed and true to the top of the engine block? Bryan (147)
1412685 2015-12-12 20:26:00 If it has been overheated the piston rings go all soft. If you have fitted new rings rings to pistons before you would know they are brittle into and can break. Ones that have been overheated you can twist them into a pretzel shape. The trick to getting an engine running with little compression is to squirt in a bit of engine oil in through the spark plug holes. Once its running and hot you can investigate further. prefect (6291)
1412686 2015-12-12 20:27:00 Easiest way to find out.
Bring one piston up to top dead center on compression.
Put compressed air in the plug hole & see where it leaks out.
Shouldn't come out anywhere on a good motor.
Most likely come will out dipstick tube & crank case breather, indicating cooked piston rings.
Driftwood (5551)
1412687 2015-12-12 21:23:00 Hi Folks.
I have this 1995 Mazda that I bought with supposedly a blown head gasket.
The previous owner had replaced the radiator which had split and when I took the intake manifold off I found a frost plug had come out. ( It was obvious that it hadn't been fitted properly )
When I first got the car home several months ago it turned over on the starter but had no compression then.
The head gasket has now been replaced and the engine put back together again.

Still has absolutely no compression on any of the four cylinders.

The engine was full of water when opened up and this has now been rectified.
It may have been overheated.
It may have been seized.

Without going through all the things that have been checked up to now, would some one like to put in their cents worth as to what they think the problem might be.
Maybe I might have missed something.
Have consulted with many experienced mechanics, gone through several Mazda forums and tried all the suggestions.

Many thanks to anyone that might find the time to add any comments.

tut Not wanting to question your skills, but in case the obvious has been overlooked.Is this an overhead cam engine if so are the pulleys lined up correctly, because this sounds like the valves aren't closing. Cam could be 180 degrees out ie bdc instead of tdc worth checking sometimes timing marks are easy to confuse.
mickb (5065)
1412688 2015-12-12 22:16:00 The best way would be to strip the engine down to the last nut and bolt, inspect, measure, check to see what needs replacing/repairing and rebuild.
That way you will know what you've got.
Terry Porritt (14)
1412689 2015-12-12 22:49:00 Or buy a good condition used motor with good compression in each cylinder and install that. You say you have consulted with "many experienced mechanics". What did they say? Richard (739)
1412690 2015-12-12 22:58:00 As driftwood suggested, the leak down test to pinpoint the source of leak either from - exhaust pipe ( open exhaust valve), coolant bubbles in radiator (head fracture), throttle body (open intake valve), and oi filler (worn/broken rings). Excellent video from eric the car guy here. (www.youtube.com)

if out by 180 degrees, the engine will rotate (assuming compression), then immediately stop with a shudder. I know - happened to me years ago when I first changed the timing belt on my 1980 ford cortina.
kahawai chaser (3545)
1412691 2015-12-12 23:19:00 I have this 1995 Mazda that I bought with supposedly a blown head gasket.
The previous owner had replaced the radiator which had split and when I took the intake manifold off I found a frost plug had come out. ( It was obvious that it hadn't been fitted properly )

The engine was full of water when opened up and this has now been rectified.
It may have been overheated.
It may have been seized.


It's stuffed.
pctek (84)
1412692 2015-12-12 23:51:00 It's stuffed.

There you have it, we were trying to break the news to tut gently pctek.
prefect (6291)
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