Head Gasket replacement - strange situation.

[Paul99]

A couple of weeks ago - taking my 66 230 to the garage for some general issues, I got the dreaded clouds of steam from the exhaust.  Once at the garage they had a look and found that on number 3 cly, when the plug was removed, water would gush out of the plug hole.

they removed the head, and the gasket.  The strange thing is the gasket looks as new, and cant see any traces of issues.  We will send the head off to be pressure tested etc, but a bit baffled as to the problem?  No water in the oil at all, but tons of water getting into number 3 - only. All other 5 clys perfect - good compression etc.

Any ideas please?  Concerned not to have found a bad gasket. 

[Peter van Es]

Injectors in there with a helicoil? Is it still ok?

[Benz Dr.]

you have to be careful under conditions like that because you can htdro lock the engine and possibly bend a connecting rod. It's much easier to do this with a V8 but it can happen.

I would be looking at the head gasket, the head,and the block. I've seen where the block or head were warped enough that the gasket didn't seal. You should be able to look at the head gasket and see if the crush was even around all of the water ports. If you have any corrosion around the ports,coolant can easily leak past that area and get into the cylinder.

[ja17]

Hello,

The cylinder head can corrode right through the aluminum from the water jacket  and eventually cause a leak in the combustion chambers. A good reason to keep the coolant fresh.  Most often a combination of loose head bolts and hot engine cause the problem.

[Paul99]

Thanks guys.  The head will go for testing.  The car had one lady owner from new until 18 months ago, it did about 200 miles a year over the past 4 years.  It did have a major engine rebuild, about 7k miles (12 years!) ago but is it true that the head needs to be tightened down at least once after rebild, and again some miles later?  Say 600 miles after rebuild?  If this is the case, it would have been 3 yearsto cover 600 miles  and she probably forgot!

Probably the same re anti freeze not being replaced.  It was running so well!  zero oil burn, and just on no 3 plug getting wet, then it went big time.  I guess i could have got away with just retightening the head before removal to try?  Anyway, working on it now, will relay back any findings in case it helps others.

[Paul99]

Looks like the head was a bodged job some years ago. Was done by a garage in London who didnt do a good job on the head.  The water insets (?) were not in right, one was sitting proud so they bashed it in to fit!  Slight crack near the no3 cly water pipe on the head as a result. It was done only 7000 miles ago, but 12 years have passed! They will weld it up and pressure test it etc. not warped at all.

Not sure if this can be recovered, but they will have a go.  A new head sounds just too much of a cost.  Quoted around £4000! plus build etc.....anyone know of a cheaper alternative? Can you still get new heads? or exchange - Is this head likly to last once welded up? This is a 66 230 UK car.