122S head gasket

[niveketak]

After my thermostat stuck and Ruby boiled I have changed the thermostat but she still boils when driven slowly so I suspect the head gasket has gone. I am taking the engine out as the sump gasket needs changing so will buy a gasket kit.
Anybody changed the head gasket, any issues with the change.

[Clan]

Originally Posted by niveketak

After my thermostat stuck and Ruby boiled I have changed the thermostat but she still boils when driven slowly so I suspect the head gasket has gone. I am taking the engine out as the sump gasket needs changing so will buy a gasket kit.
Anybody changed the head gasket, any issues with the change.

on a cast iron engine i would be very surprised if the head had warped and the gasket let go .... It is a piece of cake to get the head off of course . Maybe the gasket has just rotted though . I would try and confirm whether the engine is actually boiling or there is combustion gas bubbling through the head gasket . Does the TEMP gauge still go into the red ? Is the water pump pumping ?

[classicswede]

Hardest part of doing the head gasket is taking the manifolds off ( and compared to most cars that is easy tbh)

It might just be age with the gasket and if the engine is out it's not a bad Idea to do it. Just have the machinist take off the least amount of material from the head to make it flat.

But before you do any of that make sure the pump is pumps Ng and that nothing is blocked.

[niveketak]

Originally Posted by Clan

on a cast iron engine i would be very surprised if the head had warped and the gasket let go .... It is a piece of cake to get the head off of course . Maybe the gasket has just rotted though . I would try and confirm whether the engine is actually boiling or there is combustion gas bubbling through the head gasket . Does the TEMP gauge still go into the red ? Is the water pump pumping ?

The car has done 33000 kilometres from new but has spent 27 years parked up in various garages. The thermostat was completely seized up and I spent a good few minutes pulling it roughly apart and still didn't free it off. The cooling water was fairly brown. The temp gauge does go full deflection.

[niveketak]

Originally Posted by classicswede

Hardest part of doing the head gasket is taking the manifolds off ( and compared to most cars that is easy tbh)

It might just be age with the gasket and if the engine is out it's not a bad Idea to do it. Just have the machinist take off the least amount of material from the head to make it flat.

But before you do any of that make sure the pump is pumps Ng and that nothing is blocked.

Problem here in rural France is that there are no engineering shops who are prepared to skim anything. I spoke to a friend in our club who after 50 years of classic ownership had no idea who could do the work! We will see when its all stripped.

[Clan]

Originally Posted by niveketak

The car has done 33000 kilometres from new but has spent 27 years parked up in various garages. The thermostat was completely seized up and I spent a good few minutes pulling it roughly apart and still didn't free it off. The cooling water was fairly brown. The temp gauge does go full deflection.

perhaps the water pump impeller has rusted away , well worth getting the pump off to examine first , easy to put back with a gasket and a few rubber rings .

[Clan]

Originally Posted by niveketak

Problem here in rural France is that there are no engineering shops who are prepared to skim anything. I spoke to a friend in our club who after 50 years of classic ownership had no idea who could do the work! We will see when its all stripped.

Its unlikely a cast iron head has warped they are very tough, it's the modern alloy heads which can warp when overheated .

No need to get is skimmed until you know it is warped , you need a straight edge to check it .

[classicswede]

Originally Posted by niveketak

Problem here in rural France is that there are no engineering shops who are prepared to skim anything. I spoke to a friend in our club who after 50 years of classic ownership had no idea who could do the work! We will see when its all stripped.

I highly recommend getting teh face cleaned up both for the cylinders and the manifold and yes these heads do distort.

[blueosprey90]

No machine shop, no problem.

https://youtu.be/HyKN52HD6RU




Also, if you are simply overheating, I doubt it is your head gasket. More likely the radiator or the water passages are full of rust.

[niveketak]

Originally Posted by blueosprey90

No machine shop, no problem.

https://youtu.be/HyKN52HD6RU




Also, if you are simply overheating, I doubt it is your head gasket. More likely the radiator or the water passages are full of rust.

I did flush the radiator when I changed the thermostat but haven't checked the water pump impellor hadn't thought of that.