Head Gasket on 429 - If it were put on upside down, what would happen?

My newly rebuilt engine got hot immediately on first run. Did this 3 out of 3 tries, blew hose off first two times. It fails compression test badly.

My question it this... Can the head gasket go on upside down? If so, what would the result be?

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I ran the car this evening, and it ran very well, at 186 degrees at the T'Stat housing. Temp gauge read normal, about 1/3 of the way up or so. Same as it did in the past. This time I repainted the radiator support and fan shroud, and put them in, along with the fan. That helped. My water pump pulley has a slight wobble right now, so I have to get on that and check that I have it in completely straight. I suspect I don't!

End cause was the air pocket in the cooling system, that I foolishly missed, the first time I ran it. This caused the head gaskets to go. I replaced the head gaskets, and compression in the three low comp corner cylinders increased quite a lot. So did a couple of others. I still have lower compression on three out of the four corner cylinders, but it has just shy of a half hour run time on it now. It runs smoothly and quietly with no load, thus far. It got better after I adjusted the timing and dwell. It really runs nicely. Those three lower comp cylinders are the only spoiler.

So now I continue on with the reassembly of the car.

Let the rings seat by putting a few thousand  miles  on the engine and compression should show improvement 

Keep an eye on the oil level as it will be higher usage than normal now 

The stock rings on our engines take more time to seat than most  due to their metallurgy 

You could be just fine 

Enjoy the new rebuild 


I know that is a big relief! You expect the worse and when it turns out not to be so bad you will enjoy the results that much better. In other words you appreciate a good running engine when you get past a scare like that. Get that water pump in check you should be for smooth cruising in the coming months.



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