Jump to content

300Tdi Head Gasket change - what to do about carp in the cylinder?


SPendrey
 Share

Recommended Posts

Hello,

I'm changing the head gasket on my 300Tdi because it is/was blowing out the back of cyl. #4. After cursing a few times trying to undo everything, I found a bunch of hard crusty stuff in the cylinder. Should I just scrape it out and carry on with the H/G replacement?

Thanks,

Scott

post-11857-0-46073000-1452511683_thumb.jpg

post-11857-0-82206900-1452511687_thumb.jpg

Link to comment
Share on other sites

It looks like most I see as well, when you say 'scrape' remember that means scrape not gouge great lumps out of it ;-)

I always end up blowing debris / spilt oil and coolant out of the head bolt threads with an airline as well.

Link to comment
Share on other sites

It looks like most I see as well, when you say 'scrape' remember that means scrape not gouge great lumps out of it ;-)

I always end up blowing debris / spilt oil and coolant out of the head bolt threads with an airline as well.

Yep, makes sense. There must be little bits of rubbish that fall in to the bolt holes. Will remember to do that before putting it all back together again. Ta.

Link to comment
Share on other sites

The cam followers could do with a flush of clean oil once you finish scraping (carefully) the carbon from around the tops of the bores. You could use decoking fuel additive neat to dissolve the deposits and wipe them clean (let it soak in for a couple of minutes), and I'd recommend doing that on the head and injectors.

Link to comment
Share on other sites

One more question... been hunting for a definitive answer on which way the sealing washers on the injectors go. Many sources online imply the ridge is upwards (towards the injector), but a few claim downwards. What is the opinion here? A or B??

post-11857-0-50779800-1452683595_thumb.jpg

  • Like 1
Link to comment
Share on other sites

If it were my engine, (and I'm totally anally retentive and fastidious) and, if on removing the head I found that two or more of the cylinders were that badly coked I would drop the sump, remove the big ends and push the pistons out and fit new rings and give the bores a very light hone, but thats just me.

EJ is right (of course) it's "A" but I don't think it really matters too much so long as they are new gaskets. While the injectors are out get them ultrasonically cleaned.

By the way. what caused you to need to replace the head gasket in the first place?

Link to comment
Share on other sites

Not questioning your answer Ed, but whats the reason and why does it matter?

On A, the raised ridge is formed into a seal against the injector as it's tightened.

On B the raised lip gets forced into the hole and distorts, potentially not forming an actual seal

Or at least that's what I was taught

Link to comment
Share on other sites

All back together, and seems to be working, but made some odd sounds at first. However, after a moment of "what the hell is that?" I soon realised it was leaking water from the thermostat main hose onto the aux belt tensioner and making an odd chirp! One issue I have is that I managed to strip the thread out of one of the inlet manifold bolt holes :-( Ordered some 8mm helicoils, tap & drill to fix that, but of course it would have been much easier to do it with the head out! Oh well.

Link to comment
Share on other sites

Helicoils arrived, will sort that later, although it seems OK with only three bolts on the manifold?! Anyway, I noticed a warning on the box. It says "Always think safety before using this product". When i stripped the thread, I thought "boll*cks!", I'll have to go back and think "safety" now or they might not work.

On another note, I think the old radiator had seen better days. I'm sure there are supposed to be fins on those bars? Lucky I'd saved my old one from the broken Disco.

post-11857-0-13154100-1453217561_thumb.jpg

post-11857-0-93931900-1453217652_thumb.jpg

post-11857-0-00047900-1453217655_thumb.jpg

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy