I got my nice Citroen garage to stick a replacement head on due to a mullered exhaust stud hole.
All has gone nicely to plan until an odd oil leak has been spotted now that the car is up and running. They suspect one of the pushrod tubes is slightly cracked, which is a shame.

Unfortunately the all knowing old school 2cv guy has left, but they are doing their best to try and sort it out.

Aren't pushrod tubes quite a difficult thing to do though, if it turns out its definitely a hairline crack?

I have the same problem with mine, some days it's a lot worse than others.

I was chancing trying to find a good head to put on incase I messed up replacing the tubes, but couldn't seem to find one so I'm living with it for now.

Someone did mention (think it was Sean) that cleaning the tube up and using araldite to seal it was an "almost permanent temporary" solution.

Hmm good point, I was wondering if it could be sealed up of its just a hairline crack.

It seems the tubes would need cutting off, and the remaining little bit slotting and then pulling out. The new ones seem to be either a push fit, or need expanding once in with a thing called a reamer. None of that seems like it's too bad, on the face of it.

Ian,
for what it's worth, I've yet to see a hairline crack in a pushrod tube, however I've seen plenty of pushrod tubes which have been mangled by sloppy workmanship when refitting heads to engines.

A reamer removes material from a bore to finish it to an exact internal diameter, but that's not what's needed when installing pushrod tubes.
For that, the tool needs to expand the tube so that it's wedged into the cylinder head.
Citroen had a special piece of kit for the job, but a modified Rawlbolt will work...

Ken

Thanks Ken. I think they've avoided the usual mangling of the tubes, there's just this bit of an oil leak and they haven't been able to see where from. There's a mark on the tube apparently. I'll find out some more on Monday hopefully.

Might be a knackered spectacle seal.....much easier to replace!

Ah I supplied new ones for the job - the slightly more expensive (viton?) type from Ecas. So those should be ok. Suggestion appreciated though, i do love an easier option

The seals can leak if they aren't properly bedded on the block and if they are the wrong way up.....

If it's of any use, it took a while to find mine. I had to sit and watch it idle for a short while with the cowling a bit loose, then I could see it running down the tube from some point, but towards the engine and then on down the side of it. It seems to be coming from about where the washer sits (probably corrosion as opposed to a crack). Might be worth quickly doing that just to confirm where it's coming from.

I've never seen them cracked either but I have seen pin-holes caused by corrosion in the aluminium. If I haven't had a spare head at the time, I have found araldite or chemical metal to be successful as a "temporary repair".