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

[William R Conte]

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?

[Kim K Kaiser]

I brought this up in my rebuild in Feb.  i also ordered another gasket, and it was different than the first one!!  same supplier!!!i "made a note of that Holes in heads, gaskets, and block are not a 100% one for one match"

[William R Conte]

I noticed that too, and thought it strange. I bought Fel Pro gaskets from RockAuto, the last pair they had. They matched up hole wise with what came out. I expect to be re installing the radiator support today, and possibly the fan shroud too. I will probably start it tomorrow, and see what happens.

[William R Conte]

I see that I did not mention that I also had ended up with a low compression issue on several cylinders. Three of them were below 100, 1 was 89, 2 was 91, and 8 was 97.

I put the heads back on yesterday with the best Fel Pro gaskets I could get. I got it oiled back up with new oil and filter (break in oil used again, with WIX filter). when I did the compression test just now on the stone cold engine, all of the cylinders came up, with the exception of 7, which had 170 on compression before, and now.

I am working on getting the radiator support, fan shroud, and fan back into it. I ran without them before, just the radiator sitting on the frame with a blower on it. I'm not doing that again.

Once it's all together the right way, I will add water and try it again. I'm not expecting to have any more issue with it.

[Jason Edge]

That's great news. Glad it wasn't any thing major.. just a pain in the you know what to disassemble and reassemble.

[William R Conte]

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.

[Jason Edge]

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.

[3b0iz1uxl3e46]

The head gasket can go on wrong but it only fits properly one way. If a hose blew off the first two times it seems that a water port has been plugged off on one or maybe both sides. As for compression, it should be good right from the start. It will get better as the rings get broken in but without reasonable compression the engine won't start.

A fresh set of head gaskets installed correctly should fix the issues you have. Be sure to check your radiator and heater core for signs of damage as if the pressure was high enough to blow a hose off it may have been too high for them.