1924 6pot is steaming; head gasket or else?

[Guest lex]

Hello Reader,

My 24-41 Buick has developed a new habit: blowing the whistle, formed bij the threads of the radiator cap. Seemingly the overflow pipe cannot cope with the amount of steam. The sound rises over the driving noise.

Of course I checked oil and coolant levels before taking off. I was only doing about 30 mph and after 3m the coolant was boiling.

At home I drained the cranckcase of the white coolant/oil mixture and took the valve cover off, so the engine could evaporate as much water as possible. The radiator I drained too, but only a few liters were left.

The engine type is 116.

What I would like to know, before starting to dismantle and getting stuck for probably a long time with piles of parts:

Is it common to blow a head gasked at low speeds, or should I expect a more serious problem, like a cracked cylinder?

An european addres that can send me a head gasket would be welcomed too.

If necessary a cylinder block as well.

I would be obliged fot any informative answer.

All the best, Lex

don't hurry, be happy!

[Mark Shaw]

I suggest you first pull the big panels off the distributor side of the engine and inspect the freeze plugs for leaks.

This source of coolant in your oil would be the easiest to fix.

[Rooster]

Do a compression test on each cylinder. A low singular piston result ( or 2 adjacent bores ) will point to head gasket. Take the spark plugs out and inspect for any moisture on the electrode. Get a torch ( flashlight ) with a strong pencil beam and turn engine to TDC on each piston have a look down the bore to see if any moisture / rust there. This will identify if any water has been in there. That will be head gasket gone.

A head gasket can go at any speed. It's probably been ready to fail. Any problems before with overheating ? If so I would take the radiator out and have the top tank taken off and core rodded out. If it's a honeycomb core then it will need specialist treatment.

[Larry Schramm]

Here is a great tool.

Inspection Camera - Save on this Digital Inspection Camera

You can also take pictures of what you are looking at.

I have one similar to this one that I purchased at COSTCO and it is great. It can also be used to look up behind the dash, instrument cluster, doors, etc. besides inside of the cylinders through the spark plug hole. May not use it a lot, but worth the price when you need to see something.

Edited August 28, 2013 by Larry Schramm (see edit history)

[Guest lex]

Thanks a lot for the answers, guys!

I'll first check the freeze plugs, as Mark suggested.

Rooster, I took the plugs out when hot, they all looked about the same, one a bit blacker than the other.

And no, generally she has no problems with overheating. Even on hot days the temp keeps in the normal. The radiator core is fairly new.

I took a look at the inspection camera, Larry; in the leaflet is nothing about making photographs, which I think a necessary feature.

When I know more, I'll tell.

All the best from Lex

[Mark Shaw]

Lex,

When my dad & I first filled the radiator in my first old Buick (now my son's 29 Buick), the water flowed through the rotted freeze plugs behind the side panels and into the pan with the oil. The oil and water overflowed the oil fill tube and spilled onto the garage floor. It was like keystone cops trying to move all the cardboard boxes and stuff out of the way while slipping and sliding on the slick floor.

When we finally caught our breath, my dad said he thought we had a cracked block. I wanted to eliminate any other possibility before accepting that conclusion. Further inspection revealed holes in the freeze plugs behind the side panels, along with mouse nests, seeds, and lots of debris. One quick trip to buy new freeze plugs and we were giving rides to the neighbor kids the next day!

There is one freeze plug at the rear of the engine that normally requires pulling the engine for replacement. Again further inspection revealed a flap in the firewall a previous mechanic had made by drilling a series of small holes directly behind that freeze plug. We opened the flap and replaced that freeze plug from under the dash. Nobody will ever see that flap and it shows how old time mechanics got things done...

Edited August 29, 2013 by Mark Shaw (see edit history)

[Rooster]

I'm more inclined to diagnose a water jacket crack somewhere inside the block. I once had a 1929 head crack into the rocker chamber where water mixed with the oil.

I would fill it up with water, start it and bring it up to temperature. Check to see if there are any bubbles inside the radiator top tank. This a sure sign of head gasket or cracked head. Check to see if there is any steam coming out the exhaust , another sign of head issues. Take the tappet cover off with engine running and check to see if there are no cracks and water seepage there. If all that is good then it would spell an engine strip down and get the head and block pressure tested.

Obviously one would eliminate potential causes one by one , but it might mean for peace of mind a strip down. If so just take the head off and get that done first before diving into pulling the engine. Good Luck.

[Guest lex]

Well Mark and Rooster, I took away the side panels. The front plug in the pushrod chamber is leaking indeed, if only a drop every minute. At the rear the plug has been repaired by a former owner. Around it seems to have been treated with someting like araldite, I suppose. Unfortunately it is now the underside of the rear part of the water jacket that is leaking. I don't know if its cracked, or just rusted through. It is leaking with several drops a minute at two different spots.

I think to open both plug holes and treat the bottom of the water jacket with a water resistant coating. I'm not yet sure what, as it should be able to flex with the iron when heated and still stick to the iron as well. Any suggestions of tested solutions? Tar would be my first idea.

Thanks fot the answers, Lex

[Rooster]

I'm not quite sure where you mean by the underside of the water jacket ? A few drops leaking every minute wouldn't seem to me to be the problem with your overheating.

If your oil is white then copious amounts of water have got into the oil, or the oil hasn't been changed for a long time and those few drops a minute have added up. Although if it's driven regularly then a small amount of water should evaporate out of the oil with heat. Same as what happens with condensation in oil pan in cold weather after a long drive.

The core ( welsh ) plugs need to be replaced there's no 2nd rate attempt here. If there are cracks in the block / head they can only be repaired by welding or metal stitching.

If you want the car to be a driver in all weather conditions and for piece of mind then your engine may well have to come out.

Edited September 1, 2013 by Rooster (see edit history)

[Mark Shaw]

If I understand your description, it may be the same place where my son's 29 had a crack under the overhang on the side of the engine. That area seems to retain water even when the block is drained. We ground a groove in the crack and applied a thick coat of JB Weld epoxy to stop the leak. Since the water jacket only gets up to 200 degrees, it has worked well to seal the leak for several years. The repair is hard to see after sanding and painting as it is on the underside of the overhang created by the water jacket.

I suggest you try the JB Weld repair, replace the "freeze" or "core" plugs, and try again with some fresh oil and coolant.