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Hi,
Ive recently gotten a 79 Dodge motorhome with a 440 engine. I had to replace a cracked exhaust manifold on the right side and decided to replace both gaskets.... When i was finished and filled her with coolant, she wouldnt turn over at all. I later found out that the cylinders were full of coolant and with the spark plugs out, it sprayed everywhere.... I thought it may have seeped in through the open exhaust port when i took the manifold bolts out because the bolts do not have blind holes but go into the water jacket.... but after leaving it for a couple of days, i turned it over and she was full again!,.... i did not use the original bolts when reinstalling the manifolds but i used new 3/8" UNC bolts with a teflon sealant on the threads..... I removed the right cylinder head and the 2 rear cylinders were FULL of coolant,.....even if the sealant wasnt tight on the bolts, it seems like an aweful amount of coolant to be getting in there from that,..... especially with no pressure.....The head gasket looks fine..... Any suggestions would be greatly appreciated..... Thanks
 

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The exhaust manifold bolts don't go through to the combustion chamber. They will cause an external coolant leak, not an internal one and any leaking back down the exhaust port would require more coolant than would come out an exhaust manifold bolt hole.
I suspect you've got problems beyond the cracked exhaust manifold. If I'm remembering correctly, water doesn't circulate through the intake on a 440 so that leaves the block, head or head gasket as the issue.
 

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You might want to start with new head gaskets. If the torque down was bad, the gasket will have been compressed improperly and they don't really recover from that very well. I would use a proper set of head bolts too.
 

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I do agree with the lack of proper torque on the head bolts to start with, but what is the history of the engine?

Intake does not have any water passage in it, so Valiant67 was right about that, but, do your heads have the water attachment on the front of the heads for the water pump? Not that it really matters, all big block heads fit all big blocks, so that can't be a problem, but, did the engine run prior to the exhaust manifold change? Was there any overheating associated with the decision to change the manifold? If there was an overheating problem, the head gasket could have been compressed, then when she cooled and you did the manifold change, the fluid can pass the fire ring and if it hadn't been running after cooling, you would not see it on the gasket surface. At the same time, the heads are pretty tough and rarely warp or crack, which, hard ot say for sure, and since the head is off, get it magnafluxed and pressure tested before reinstalling. I take it the left head showed no signs of fluid in the cylinders?

Additionally, the bottom row of head bolts do pass into the water jacket, make sure they and all the other bolt threads and bolts themselves are clean so they don't catch on dirt and show the improper torque readings.
 
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