water leaking from the head gasket

[JarrettF]

I replaced the head gasket, among other things, and the engine started right up after I put everything back together.

What a great feeling.

But then I noticed that it was leaking water from the head gasket - one stream from the starboard side, shotting just aft of the alternator. And on the port side, enough to create a steam from between the manifold and the head. One of the stud nuts has a drop of water coming through it...

Unless I am misusing the torque wrench all of the stud nuts have been torqued to 35#.

What to do?

Are the studs not deep enough into the water jacket? Should I hank on the nuts and force the head down onto the block? How much torque is too much here? And is this normal, like incoming water until the planks swell up (will the gasket eventually seal completely after some time?

[JarrettF]

hmmmm....

after having an absolute devil of a time getting (many of) the studs out I resisted putting JB weld or some other kind of nearly-permanent goop on the threads into the block...I used Tef-gel. Could this be the problem? Must one use a epoxy-like sealant on the threads into the block?

[sunnnnseeeker]

I recently put my engine back together. Had new head studs and used Loctite High Strength Threadlocker "Red." I started the engine and sure enough I had water leak. Turned out the head had a leak that was not visible with the naked eye. I purchased a new head from MMI, installed and waterleak problem resolved. You can not re-use a head gasket. Once they are smashed and their graphite sealant squashed out they will never seal again. I initially torgued to 35 ft lbs. After engine warmed from running and cooled all the head bolts were loose. It took 1/2 turn to get them back to 35 ft lbs. Another cycle of running and cooling the stud nuts took another 30-40 degrees to get them back to 35 ft Lbs. One more cycle and one more nudge with the torque wrench and all nuts are holding at 35 ft lbs.

In your case if water is squirting out from the head gasket either the gaskets (did you use 2, one on top of the other - you must!) broke during installation or the head is not flat or both. Also, maybe you didn't get all the old gasket off and the surfaces were not clean? That was a tedious task for me. The old gaskets were really stuck on both the head and block.

In anycase, it sounds like you need to start over. Buy new headgaskets (must use 2), make sure the surfaces are clean and flat and torque to 35ft lbs starting in the middle and working your way out. Try to keep the nuts all the same tightness as you tighten it up a little at a time on each nuts. You'll have to go around the head many times before you get them to 35 ft lbs.

If you are not sure the studs are locked in tight and sealed take them all out, clean everything off including and oil. Run a tap in the head holes to clean those theads. Then re-set the studs using generouse amount of locktite. Don't worry about having to remove them again, if you do and they do not budge because of the locktite a little heat with propane torch will free them up. If your headstuds are not in good shape put new ones in. They should have at least 4 full threads on the studs and at least 4 threads in the block must be there. Sounds like you are OK with the thread if they held the 35ftlbs.

DO NOT "hank" on the nuts or you'll strip the threads in the block.

Good luck - let me know how you corrected this problem.

Nathan.

[JarrettF]

How could it develop a leak, or a crack after removal? Why wouldn't it have been leaking before, with a head gasket that was shot?

And why would water then be coming up through the bolts?

[adab1402]

welcome to the wonderful world of gremlins

first remove head ,next step is get thee hence to a qualified machine shop ,pressure test ,magnaflux and check for flatness . part b check block for flatness ,borrow a str-8 edge from your machine shop . eyeball and wiggle all studs ,no play ? great ,clean .all mating surfaces ,re-install head ,new gaskets ,use a 3 step procedure to torque head ,take your time and be positive ,it,s not brain surgery ,take your time and enjoy the bonding time . fair winds adab

[sunnnnseeeker]

Mine actually did leak before I took it apart. I thought it was coming up through the bolts or the gasket was shot. After I got it all back together with new gaskets and studs sealed in and new paint on it it was easy to see where the water was seeping through a small crack. The water leak cracked the paint. Solution = New Head.

Nathan

[JarrettF]

Actually, I'm just an idiot.

I torqued the head down to 35# alright, 35 inch pounds! So about 3 foot pounds!

I bought the only torque wrench in the damn Sears and thought it was a real torque wrench. Turned out it was the MicroTork.

After returning to the boat with the right tool, I proceeded to strip out the third bolt I touched. So back to waiting for parts...

Thanks for your helps...

[sunnnnseeeker]

35 inch pounds....That will do it. What happened? Did the stud pull out of the head? Make sure you are not going over 35 ft lbs or even 30 ft lbs if the studs and the threads in the head are not at least 4 deep. If one pulled out the others are likely not far behind; wanting to let lose. I would take the head off and the studs out and really see what you are working with there. New studs may be necessary. Word of caution - better make sure you have the water out of the cylinders while you are doing this work. Rust will form over night on the cylinder walls.

[Don Moyer]

In addition to all the good help you've already received, you might find the attached instructions useful for installing a repair stud without the need to remove the head again. Also, Universal informed us many years ago that if you have any concern over the integrity of the stud threads in your block, you can back down on the torque value a bit (Page P1-3 in our MMI Service and Overhaul Manual). They (Universal) claimed that they had actually tested engines successfully down to 30 foot-pounds. Your 3 foot-pounds stretched this envelop a bit.

Don

[JarrettF]

Thank you all for your help. And for not making fun of me for mixing up torque inches and torque pounds. I'm surprised more water wasn't shooting out of the head - I basically had everything just a little more than hand tight.

And Don, thanks for the pdf, but I already took the head off just to make sure there was not a puddle of water in any of the cylinders...all clear. I lucked out.

Thanks again, everyone.

[JarrettF]

Went back today and replaced the stripped stud with the fix-it kit (Thanks, Don!).

Torqued everything down to 15, then 20, then 25, then 30. Started it up and no leaks.

I do believe the engine is fixed!

Thanks, everyone, for the multiple answers and advice over the past 4 mos while I traced and fixed the problem. The forum was indispensable.

[respite]

Exhaust flange top bolt leaking water

Hello,

I’m a new owner of a 78 Catalina 30 with a MMI rebuild A4. The engine appears to run great except that I needed to replace the hot section.

During the process of installing the hot section on my Catalina 30, I stripped the threat where the exhaust flange top bolt attaches to the manifold . A friend suggested installing a 3/8th Heli-coil to repair the threat which I did. Now water is dripping from the top bolt.

Could this be a torque problem? I just hand tighten the bolt as tight as I can.
Does any one know what is the appropriate torque setting for the Exhaust flange bolts? 35?

The manifold top threat hole is approximately ¼ inch deeper then the lower threat and leaks water where the lower threat doesn’t. Is normal?

I was thinking about using a High Temp Gasket Maker like the Permatex Utra Black then installing a longer bolt (1 ¾). Can this seal the leak? Is this a good Idea?


Please help.
Any ideas will be appreciated.

[Don Moyer]

The problem you're facing is that the upper bolt of the exhaust flange threads into the water jacket of the manifold (while the lower bolt does not). Your experience with Heli-coils is the very reason we discourage their use anytime you are penetrating into a water jacket; i.e., they're simply too difficult to seal. This takes nothing away from Heli-coils in other applications; they are very strong and otherwise reliable fasteners.

Since you already installed a Heli-coil, I do not recommend removing it, as the threads are unique to their product. In our shop, we will usually will use a stud in that hole (if it leaks) and use JB Weld to seal the threads of the stud and try to work the JB Weld into the coils of the Heli-coil as well. You can see what those studs look like here in our online catalog.

Don

[67c&ccorv]

Guys, all threaded fasteners on an A4 (or any motor) have a torque value which I can guarantee you will not be able to "feel" by hand tightening - get an accurate torque wrench and learn how to use it! It is a precision instrument (not a tool) and should be treated as such. That is why I don't lend mine out, at least not without a $200.00 deposit.

All assemblies which are fastened by more than one nut or bolt must be removed and tightened in the required sequence so as to avoid warping or in the worst case scenario, cracking an improtant casting like the cylinder head.

Get a manual, get the proper tools, take your time - remember, its' not "flat rate" work you are doing!

[respite]

Thank you Don,

I'm planning to used the studs you recommended. I'm assuming that a 35 pount torque should do job. Is that correct?