Exhaust port leaking water

[Finn Flatty]

Hi,
I have a freshly rebuilt 8ba. Started it today for the first time and
to my disappointment realized that the driver side exhaust is leaking
quite a lot of water, the leak comes from the last exhaust port, cylinder #8.

It's quite hard to look into the port, but when touching with fingers you can feel
a sharp corner, maybe something like a small cracked piece.
Pouring water does not help finding where the leak is.
There are repaired bolt holes with helicoils. I'm wondering if the bolts have been drilled too deep.

There is a strange "tap" in that port pointing upwards. Please look at the picture attached.
Would you have any idea about that piece in casting.

A well-known builder here in Finland put the motor together and I did not
suspect a problem like this would arise, but here I am with an issue...

-Pasi

 

[JSeery]

That is not a small crack! Was the block pressure checked? I would not know of any way to repair a crack like that without taking the block apart and having it blazed up, and even that might be a challenge.

 

[scooder]

There's two things in that port. One long sticky out thing, this is a fairly common find, left over from casting cores. I normally just snap um off. Looks like the other maybe some thing like a drilled out bolt that went too deep.
Other thing I noticed, you said first time start. There certainly appears to be a coolant leak at the head gasket right there, you sure it's not from here that the coolant is coming?
Martin.

 

[Pete]

That can be silver soldered without dismantling the engine.
The engine will have to be out of the car though.

 

[JSeery]

Well, maybe my eyes aren't that good! Looked like a crack in there to me, but scooder may have it right. And it does look like the head gasket is leaking all along the side.

 

[scooder]

That is not a small crack! Was the block pressure checked? I would not know of any way to repair a crack like that without taking the block apart and having it blazed up, and even that might be a challenge.

I'm only looking on my phone, will get me 'puter fixed one day, not sure I can see the crack.
Could you point it out please? Maybe can't get the pic Big enough here.
Martin.

 

[scooder]

Posting at the same time!
Martin.

 

[Tony NY]

Looks like leaks around the head studs. Probably the threads. I think if the exhaust port was badly leaking there would be carbon free metal where the crack is supposed to be.

 

[bobH]

That can be silver soldered without dismantling the engine.
The engine will have to be out of the car though.

You've got me wondering... I abandoned a 59A that I had rebuilt by a local flathead builder, because of something similar. In my case, the leak(s) are at the right-front. Water comes out the #1 exhaust port, and also out a hole that is at about 11-o-clock above the cam gear. The hole over the cam gear can be seen, and presumably can be repaired. The builder and I abandoned the block because we can't see the leak in the exhaust port, and assumed that if we could see it, we would have no way to repair it. Comments, from Pete, or anyone?
We also assumed that the block must be 'weak' in the right-front area, and we would be reluctant to trust it, even if we did manage to repair existing leaks. Comments? Might we have success with silver-solder, which we would have to apply pretty deep into the port? Do you think a repair could be trusted?
My motivation is that I have quite a few bucks into it, with Merc crank, fresh bore & pistons, balance job, mild cam and more.
No intent here to hijack this thread. I simply think it's almost the same problem that the op has posted.
Thanks

 

[Pete]

You've got me wondering... I abandoned a 59A that I had rebuilt by a local flathead builder, because of something similar. In my case, the leak(s) are at the right-front. Water comes out the #1 exhaust port, and also out a hole that is at about 11-o-clock above the cam gear. The hole over the cam gear can be seen, and presumably can be repaired. The builder and I abandoned the block because we can't see the leak in the exhaust port, and assumed that if we could see it, we would have no way to repair it. Comments, from Pete, or anyone?
We also assumed that the block must be 'weak' in the right-front area, and we would be reluctant to trust it, even if we did manage to repair existing leaks. Comments? Might we have success with silver-solder, which we would have to apply pretty deep into the port? Do you think a repair could be trusted?
My motivation is that I have quite a few bucks into it, with Merc crank, fresh bore & pistons, balance job, mild cam and more.
No intent here to hijack this thread. I simply think it's almost the same problem that the op has posted.
Thanks

If you can see the crack, you can fix it most of the time. No see, no fix.

 

[Walt Dupont--Me.]

I think you'll find that pointed thing you can put your finger on is just core wire, you'll find them in most blocks, You said there are few heli coils in the block. Is one of those coils in the rear head bolt? The rear exh port is real close to that bolt hole, it's possible that some one drill to far for the coil and got into the port. Walt

 

[Ol' Ron]

Yup! Dats the problem, lost a good block that way. You might fix it,BUT!!!!

 

[A bones]

If... it is a stud hole repair... can it be sealed from upstairs?

 

[Finn Flatty]

Today we'll take the head of to see if a helicoiled hole is situated on that corner where the problem is and to check if the coolant leak might be at the head gasket.

There are two fixed bolt holes on heads, and four helicoiled ones on exhaust port areas, one also where the water comes from.

I attached a closer picture for those who have smaller screens, though that image which was taken with a piece of mirror only shows the core wire which, as you commented is fairly common.

 

[Mart]

I read a thread on one forum (can't remember which) and a previous owner had drilled too deep when repairing a stud and drilled into the center exhaust port. He was able to tap the hole and screw a small (1/16" NPT) plug into the hole in the port. You might need to do something similar.

Mart.

 

[JWL]

I am having a difficult problem with trying to recognize that engine?? What is that behind the mirror? Appears to be a series of small core plugs in a circular pattern? Also, I don't recognize those holes at the rear, outside, of the block? Maybe the perspective these pictures provide have me undecided?

Now, to the leak----FIRST it must be specifically located. Then we can suggest repair procedures.

 

[51 MERC-CT]

Two head bolt holes (marked in yellow) go into the coolant core, the one marked in green is blind and if drilled too deep could break into the exhaust port but does not look like it would come close to any coolant core.

 

[scooder]

I am having a difficult problem with trying to recognize that engine?? What is that behind the mirror? Appears to be a series of small core plugs in a circular pattern? Also, I don't recognize those holes at the rear, outside, of the block? Maybe the perspective these pictures provide have me undecided?

Now, to the leak----FIRST it must be specifically located. Then we can suggest repair procedures.

John,
The "series of small core plugs in a circular pattern" are the nuts on the bolts that hold the starter plate on the bell housing..
I'm fairly sure from what I can see, the thing in the port that ain't a core wire is a drill breakthrough. Which would have been caused by drilling out a broken bolt in the lower corner, it should not have happened as the threaded hole doesn't go all the way down to the exhaust port. But appears that's what has happened.
As my buddy Mart said, it can be fixed by drilling and tapping the breakthrough for a small screw in plug.
Fiddly but fixable, much easyer than a crack.
Martin.

 

[Ol' Ron]

In my engine the yellow arrow was broken into the exhaust, powring water into the exhaust. I used a threaded rod to repait it with some Hi temp epoxy. It did work to some extent but I was getting water in the oil. I thought of using some stop leak but decided the block was not a reliable unt and scrapped it. Installing all the components . except pistons. Into a 59a block.

 

[truck]

Hi all,

The topic starter's, Finn Flatty's, car is in my garage and i am helping him to get the car rolling. However, this is my first flathead i've ever played with.

I tried to narrow down the possible leak source by unbolting a head bolt one by one around the cyl #8 and pouring water into the cooler. At least, next to exh #8 the bolt holes where bolt head paint-marked in white are thru to the water jacket (pic 'waterbolt'). There was no sealant on the bolt threads. Are these bolt holes normally drilled all the way to water?

Next removed the head (pic 'headoff'). Nothing wrong there that i can see. Can you point out which bolt holes might crack to exhaust #8 - to take a closer look?

The leak is in the exhaust port somewhere quite near the exhaust flange, since the water is not getting into the cylinder neither oil pan.

Any help is greatly appreciated.

Thanks.