Santana 27 exhaust system

[JOHN COOKSON]

Hello Afourians,
I bought a head gasket sealing product (with nanofibers, and other BS in it), but didn't use it yet. Every car mechanic says that such head gasket and engine block sealing/repair products are useless. Does anybody have any experience with such products at all?
~Laszlo

If you're RWC I suspect it wouldn't work at all. In a car engine coolant is pumped 'round & 'round. In a RWC boat engine water is pumped through the engine. If your A4 is FWC it will work for a short period of time or not at all. At least that was my experenice with the stuff.

How much water is getting into the oil? Enough to raise the level really high on the dipstick? Or just enough to make the oil look like a chocolate milkshake?

TRUE GRIT

Edit: Unless there is a new product out there this stuff is made for leaking radiators; I can't imagine it working on a hole in the block.

[Laszlo]

I will do some pressure test, but I am afraid I already know the answer. How else would the water get into the oil?
The level increases on the dipstick noticeably. The system is RWC, but my plan was to capture the outgoing fluid in a bucket, and recirculate it through the block a bunch of times. I wouldn't want to dump that thing in the water anyway. But if it's useless, I would rather not waste my time.

[Whippet]

exhaust

good-looking work on the exhaust. Must seem like small pleasure at this point given the water-oil issue. Let us know how pressure test goes.

[JOHN COOKSON]

I will do some pressure test, but I am afraid I already know the answer. How else would the water get into the oil?
The level increases on the dipstick noticeably. .

See oil system FAQ #4 for some ideas. The idea of dead heading the pump sounded good. Also there are some A4s out there that were built with a mild steel plug to seal off holes in the casting that later have been failing. As best I can recall the plugs were in the lifter area. I'll try to do some research when I get the time.
In any case a pressure test is the next step.

TRUE GRIT

[joe_db]

A thread or two up a couple A4s are for sale - just sayin.

[Laszlo]

I finally got around to doing a pressure test. I removed the T-fitting at the water jacket inlet, and plugged it up with brass plug. I also plugged up the inlet of the thermostat housing. I came up with a way to attach a Milton valve to the cooling water outlet, and apply pressure with a bicycle pump. I pumped up to about 40 psi fairly quickly, and noticed a hissing sound, and water seepage from the bottom left corner of the water jacket inlet cover. At that point decided to dismount the alternator, water jacket inlet, exhaust manifold and valve cover. I was going to remove the head as well, but I don't have the stud remover tool yet.
I am attaching a few pictures of what I found. In my estimation the rust issue looks pretty grim, and I am wondering on opinions how bad it really is. The bolts on the water jacket inlet were completely rusted away. It seems that not much was holding them in place. Obviously the water jacket inlet cover plate, thermostat housing, probably the head as well will need some sand-blasting and cleaning. I will order new gaskets, etc... Then, I might be able to put the engine back together, and perform the pressure test properly. There is a chance that the water leak issue might be solved with all this. However, looking at the water jacket, there is a lot of rust in there. Do all A4 engines look this bad before an overhaul? Should I try to get the whole block out of the boat while I am at it? Due to the space limitations hauling the engine out might be a challenge.

[Laszlo]

Hello Afourians,
I thought I give an update on this thread. Moving forward with tracking down this water leak issue, I took off the head, the manifold, valve housing cover, and water jacket cover. I sandblasted and painted them, cleaned all up the threads by running a tap through them. I also tested the original late model thermostat (double-action) in with hot water, and it worked just like a charm.
Today I got around to put the engine back together, and do the pressure test. I could still detect the hissing sound coming from around the water jacket side plate. I used soapy water to identify where air is escaping. I took the side plate off several times to sand out all the small erosion pits, apply some sealing paste, etc.. to stop the air escaping, when at some point I finally managed to ruin one of the bolt holes. Interestingly I didn't rip the thread, but rather unfortunately cracked the side plate, even though I was careful not to over-torque the bolts. I am attaching a few pictures. I suppose the right way to fix it would be to carefully tap that chip back into its place, and then weld it. I would feel rather uncomfortable doing that in the boat, and I have no intention of pulling the engine out. I think I will try and fix it with the water jacket side plate repair kit, and JB weld that chip in place as it is. Are there any other suggestions for fixing it?

On a different note, earlier this month I cut that old standpipe open with an oxy-acetylene torch out of curiosity. I am attaching a few pictures. The thing was rusted out, but the pictures show how it worked. Pretty much what you would expect.

~Laszlo

[hanleyclifford]

I like the JB idea. You might consider modifying the repair kit so that the backing plate is centered behind the repair. Alternatively you could consider abandoning the hole and sistering two new ones either side. Definitely go the all stud route when you put it back together. Neil had a good idea using brass nuts that become sacrificial in the event of difficult removal.

[Administrator]

Pin hole leak in one of the cylinder bores below the normal piston travel? (Don)

Bill

[Laszlo]

Hi Bill,
I am not sure I understand correctly what you are referring to. Were you pointing out that you saw indication of a pin hole leak in one of my photos? Could you elaborate? I am curious.
Laszlo

[Administrator]

Here's the entirety of Don's note to me:

Lazlo has done an incredible amount of good work. At this point, he
doesn't have to put the whole engine back together. He's better off just
reinstalling the head, then filling the block and head and doing a pressure
test. That way, he'll be able to visually see where water is escaping from
his leak. None of his photos shows any obvious internal water damage that
would indicate a breach in a water jacket around any of the combustion
chambers, leading to the possibility of a pin hole leak in one of the
cylinder bores below the normal piston travel.

Bill

[Laszlo]

Block cracked

Hi Everyone,
Recently, with the nice weather's arrival, I got back to the engine. I was pleased that the engine started up, and was anxious to see if the head gasket replacement fixed the water leak issue. Unfortunately it didn't, furthermore I saw signs of trace amounts of water seeping to the outside past the head gasket. I had followed the instructions for torquing the nuts on the head, and didn't want to over-torque, there was clearly something else wrong. So I took the head off again to investigate. I found that the corner of the block is cracked. This must have been the issue all along. I am attaching a picture. The last two stud holes in the rear right corner are both cracked across to the water passage. In addition there is a crack going diagonally out towards the outside wall of the block.
I think the engine will have to come out of the boat. I am wondering what is the best course of action here. I appreciate any advice.
Laszlo

[Don Moyer]

Block cracked

Laszlo, there are a lot of Atomic 4s running around with cracks on the decks of blocks, and as long as you can torque the head studs to around 30 foot pounds, they usually don't result in leaks. Are you certain that you're seeing water manifesting along the head gasket in the exact location of the cracks? Any water appearing in your oil? That would be the case if there were any pin hole leaks below the area of piston travel. Don

[Laszlo]

Hi Don,
The location of the water seeping outwards was exactly in the same place where that diagonal crack reaches the outside wall of the block. Traces of rust carried by the water trickling down made it very obvious. A little more background on my observations. At first I torqued all nuts in the order the manual suggests in multiple steps. Then I ran the engine a little bit with no cooling, just to get it warm. Then I re-torqued all the nuts. Then I ran it again, and re-torqued again. Only after this did I open the cooling water through-hull. I could see a little bit of water seeping up to the top of the head past the stud that is in the hole with the diagonal crack. At this point I hadn't yet noticed the water seeping to the outside. I torqued that nut a little higher (38 ft-lbs i believe.) I didn't see any more water coming up past the nut. After a while I did notice, however, water getting pushed through past the spark plug in the rear cylinder (#4). I also noticed water getting into the oil. Only then did I discover water seeping out past the head gasket into the gap between the block and the manifold.
I know that water was getting into the cylinders, I found a bunch of it in #4, and a little but in #3 after I removed the head. I think water was getting into #4, where it slowly built up, and once there was too much of it in the cylinder, it got pushed over into #3 due to incompressibility. I mostly suspect those two studs holes for letting water get past them. Also, the area on the block around the stud hole with the crack wasn't completely flat. I think someone must have pulled quite hard on the stud at some time in the past. The picture was taken after I sanded it down gently with a sanding block.
Laszlo

[Don Moyer]

Laszlo, Sorry, but it’s still difficult for me to know the source(s) of your water leaks from your report. Before giving up on your block, I suggest the following:

1) Smear a thin layer of JB Weld on the gasket surface of the block around the opening of the water jacket side plate. From your photos, the surface of the block is too irregular to seal reliably. Then use one of our water jacket repair kits (Product No. - KTAS_05_307) to replace the bolt in the hole with the broken wedge. Use lots of a good tenacious sealer like old Permatex aviation brand on both sides of a new gasket and reinstall the side plate.
2) Reinstall the head studs using the original slow-set JB Weld to seal them, particularly if any of them have a sloppy fit.
3) Smear a thin layer of JB Weld on the deck of the block in the area of the cracks, especially in the area where it seems lower to you.
4) Reinstall the head but leave the manifold off.
5) Allow the JB Weld to cure overnight, then fill the block and head with water up to the thermostat housing and do another pressure test to approximately 20 psi. Email me at; info@moyermarine.com if you need a guide for pressure testing. During the test, look in through the spark plug holes for evidence of water leaking into the cyilinder bores and up through the valve ports for leaks in that area of the block. Don