Y-Block Heads Seeping

I just finished rebuilding my 292 Y-Block with my father-in-law about 300 miles ago. Recently I noticed that Oil was seeping out of the heads and trickling down the sides of the block. I didn't think too much of it because it wasn't very much oil. During this time I was also running straight water in the radiator. Recently I changed the radiator to have a 50/50 antifreeze & water mix. After doing this I now have noticed white lines in the same locations as the oil seeping from the heads. Am I right to assume that the white lines is coolant seeping out? Should I be worried about this? Could the head bolts just need to be torqued again? My brain is telling me to check the head gaskets (which are new) but I'm really hoping I don't have to... FYI, when we rebuilt the engine we did not deck the block or heads so I'm wondering now if maybe their isn't a little warpage.

 

Retouque, add stop-leak to coolant, watch for oil in radiator and coolant in the oil, run it.

 

of some reason y blocks is often warped in the deck area
always use atleast a straightedge to control warpage
not only on yblocks but on all engines

 

I'll retorque and see what happens. I used Bars Leak in the radiator when I first got the motor going, should I do that again? So far there doesn't seem to be any water in the oil. What are the signs of oil in the water? Would it be milky?

 

Yes on the milk, hot oil and hot water, yes make milky substrate, whether its in the rad or under the valve covers, milky pukey looking goo. And no on the second bars leak. Please dont do that.

 

ok cool, well so far oil and water are fine. Just white seepage from heads. Just ran the motor a little earlier and had some white smoke but I'm not sure if it was due to coolant or maybe running rich. The truck has sat for a few days so I think it may also be condensation?

 

I am not a Y-block expert, so I have to ask are the head bolt holes blind? That means you cant see into the water jacket, or are they through bolt holes. Pull one out and use a piece of coat hanger if your not sure. If they are through holes, you need to use sealer on the threads, that should help your problem.

 

Honestly I don't remember if they needed sealer or not... It was all put together a few months back.

 

Use the coat hanger deal to be sure, I am leaning toward the holes being through holes, I am sure someone will chime in who knows for sure. If they are they will seap. Not trying to be pushy, I just have a great admiriation for the old iron mills, and hate to see a fellow HAMBer on the side of the road with his overheated ride.

 

You're not being pushy at all, I appreciate the help. I could have just put something newer in my truck but I really wanted to rebuild the Y-Block. I'm glad I did because it stands out amongst all of the small block chevys.

 

There are two head bolts that are shorter then the rest,I think they are on the ends toward the bottom of the head and if you put the longer bolts in those holes the head wont tighten correctly.

 

Both are an indication of coolant where it shouldn't be. Changing from an oily apparance then this, indicates something is changing.
Were the head gaskets put on dry or with some kind of sealer? Should never use anything, it just deteriorates from the heat and then the space it took up loosens up the works.

 

Like bulldogmafia says, sealing the bolt threads is the first thing to do.

Of course if it's just leaking gasket that should be remedied by milling the heads if the problem persists.

It might be worse than we would want it to be. I'm thinking head gasket(s) seeping OR cracked head(s).

If you decide to take the heads off to explore, I suggest you flush the coolant, put in pure water, then run it before teardown. After teardown, don't clean anything up, let them sit for a couple of days and it there are any cracks they'll show up as rust tracks, like you drew a line with a rust pencil.

 

Gaskets went on Dry.

 

I'm pretty sure these went in the correct locations. It seems that the coolant is seeping out of the rear portion of the heads, does that make a difference?

 

Pabst, are there freeze plugs in the ends of the heads? A pressure test is probably in order. You might be able to rent a test kit at the auto parts store. Need to pressurize the coolant system and watch the leaks, see if you can tell EXACTLY where the leaks are. How about a water passage in the rear of the intake?, could be intake gasket if theres a passage back there. If there is one, could it be leaking and running down and accumulating around the block deck edge making it appear to be head gaskets.

 

Nope, there aren't freeze plugs in the ends of the heads. Looks like I'll be pulling it all apart to see what's up.

 

i had a bit of seepge on the startup of my motor, right down the side of the block . it dried I wiped it and nothing else has come out ... mine is a y block , but you have to do both sets of touques cold and hot to get them to seal . also I hear the copper gaskets are crap and will leak even though ive used both felpro and copper , oh and the head gasket copper spray is a must .... hope any of this helps... oh and if you do pull the heads and deck em tell em to take a few thou off for compression haha every little bit helps.

 

WRONG The end bolts are longer and if put in the middle holes may bottom out. Then the gasket will not seal.

And if I remember correctly, none of the head bolts go into the water jacket.

 

Thanks for all of the input guys. I used Fel-Pro gaskets when we put the motor back together. I am going to re-torque the heads this weekend and hope that does the trick. This is my first real full rebuild so I'm not sure what to expect, and I get a little bit like 'chicken little' everytime something happens.

Paul - I think you're right about the bolts not going through water jackets.

 

Whenever I have something apart, I trace the gasket on cardboard, punch holes in it and put the bolts through it as they come off the engine. It works for everything from water pumps to major engine hardware. Also, when in doubt, put sealer on the bolt.

In your case, I'd re-torque the heads and intake, follow the pattern from your reference material. Then toss in a dose of Solder Seal Block Saver or an equivalent product. Great PM for any rebuild. It may be hard to find, older auto parts stores usually have it.

My experience with Barrs is that it congregates in heater cores and radiators making either or both less effective.

Bob

 

I think your right on the water jackets.

The question becomes this. What kind of head gaskets did you use? I used to use steel shim gaskets on my 312 and they got coated with copper coat before they went on. After initial warm up and cool down they got retorqued. Some gaskets need to be retorqued it was common when that engine was built.

One of the things that happened when you went back to the dealer with the new car @ 500 miles was that they adjusted the tappets and retorqued the heads.

On modern head gaskets most do not require a retorque but some still do. After 40+ years of wrenching I still read the instructions that come with the gaskets.

And yes to the earlier Y Blocks need to be decked and the heads faced prior to reassembly. They have a tendency to warp in the deck area.

 

I used Fel-Pro gaskets, the head gaskets were fiber faced so they didn't need sealer. Ill check through my service manual for the engine and see if it mentions a re-torque on the first service.

 

and sbf,s and flatheads too good luck with the y-block there alot of good help here and also on y-blocks forever

 

With the Felpro gaskets you shouldn't have to retorque. They would have specified a retorque if they needed a retorque.

It probably wouldn't hurt a thing to retorque anyway. What it'll cost you is about half an hour. Then clean your rngine real well and drive it.

I don't know what your weather is like there but its real humid here. You can park one for a couple of hours just long enough to cool off and get condensation in the tail pipes.

 

Pull the top row of head bolts out to make sure the long ones are on the end. Retorque in increments , start at 45, go to 55, then 65 and do 65 twice. If you take the heads off this time, and the bolts are in the correct place, mill the heads .020, then to take up a possible wavy block, put two coats of KW Copper seal on both sides of each new head gasket. Use a thread chasser in the block holes, and a wire wheel to clean the bolts, then lightly oil the bolts on reassembly.