I've just put the engine back in the car and had the exhaust guy weld the headers back to the exhaust pipes. The exhaust guy said he had to tighten the headers down to stop a leak. Now it's blowing water out the tail pipe. The engine is a 65 426 with d 4 heads. Do you think he cracked the heads? Thanks

From my own personal experience with 440 heads, the header bolts require sealant, like ultra-blue, on the threads or they will leak coolant. 440 heads exhaust manifold bolts do go into the water jackets, so sealant is required. Could the water coming out of the exhaust be condensation? Do you have sealant on the header bolts? Those are 2 questions that may help diagnose your troubles. Good luck!

The water is coming from the radiator, It's geting low. I know the 440s need sealent but does the hemi also need it? Water is also coming from the drivers side only. I didn't put anything on the header bolts. Thanks Jimmy

It is possible that there was some junk in the bottom of a bolt hole that when the header bolt was screwed in punched a hole through to the water jacket. I have seen this happen so many times its disgusting. Takes a minute to clean out bolt holes with a tap or high pressure jet, even poking a pick in there will get it and yet people keep doing it. The give away is that the bolt was tightened to stop the leak. If the bolt had bottomed out the extra torque pushed something somewhere. )added) sorry I went on a rant. Pull the header bolts one at a time if you strike water you've found the problem. I don't think D4 Hemi heads have bolts into the water jackets.

Shot the heaaders with a temp gun, looks like it's the #1 cylinder. It's running running cooler than the rest. What's the best way to fix it? Thanks

I had the same thing happen to me on a 340 stroker with ported X heads. My head was leaking water into the cylinder; pull the plug and see if you have water in the hole.

Good luck;

If its No 1 you may be real lucky. I say that because you can probably put a stud in what ever hole it is and still be able to remove the headers. Find out which one it is and I would use Locktite 565 P8T pipe sealent on a stud and run that in. Its always worked for me on B's and RB's. You dont need to torque the stud just get in in to where the nut will have enough bite to tighten up (kinda like main studs on a block). Good luck. Oh, if you want to reuse the bolt that may work. However, on most of the iron BB heads I've worked on once the studs are pulled you almost always have to heli coil the heads because the threads are shot. Thats just an afterthought. Good luck.

Thanks for the info. I'll need a full weekend to pull the headers, there custom made because of the d 4 heads and a real pain to remove. Someone told me to try k&n block seal. Has anyone tried that? Thanks

Before I would pull the headers I would try an identify which headers bolts are leaking by pulling the bolts one at a time. Then I would to seal that bolt with some sealer. I don't like block sealer. Might save you a weekends work. I don't like to add anything to my cooling system except antifreeze and water wetter. To many radiators have been plugged up with other stuff.

Thanks, I'll try one bolt at a time

How does lack of sealant on a header bolt allow water into the tailpipe?

Unless the guy he-man tightened the stud/bolt so far to crack the head between the bolt and the port, but then I think you'd have an external leak also.

I don't have a clue. I ran the car with headers for a few days with no water leak. After the guy welded the headers to the exhaust he said he needed to tighten the headers because of a leak. The next day water started coming out of the tail pipe. i put the car on the rack no leaks anywhere but the tail pipe. Thanks

depends on the guy that tighten it....did he remove the stud or turn the stud in deeper?...he could of messed up the seal on the stud and the header gasket...

I can't find header gaskets for the d-4 heads, if you know someone that sells them let me know. I did use a copper spray on gasket. The guy told me that he just tighten them down, he's a big fellow also. Thanks