Jump to content

Recommended Posts

I recently did a full rebuild on my discovery 200TDI converted Series 3. It just completed its 500 mile break in period without any issues.

Now, in the last 100 or so miles some strange things have started to happen. The first was the heater core which started leaking, eventually blowing and dumping litres of coolant into the cab. The next thing to go was the radiator. I replaced both as they were over 20 years old and put both failures down to coincidence since there were no other signs to point to HG failure. 

After another 100 or so miles I noticed that the heater output was erratic and the expansion tank seemed to overflow even when half filled. Even though there was no smoke, bubbles or oil/coolant mix, coolant loss, or loss of performance, I now suspected HG failure.

I ended up taking the head off and noticed a very obvious bulging of the fire rings as well as rust marks between the manifold side of the cylinders and water jacket. The second thing I noticed was that the head bolts in the area where rust had formed (Turbo side) required less force to remove. I.e were less torqued down then the others.

Now, I want to be honest and admit to my great shame that I used a Britpart MLS head gasket which appeared to the eye at least to be well made. I followed the tightening meticulously, 40nm, 60degree's, 60degree's. Both the head and block decks were flat (Checked with a straight edge and feeler gauges), clean and all the headbolts lightly oiled.

I have since ordered and fitted an Elring composite gasket with brand new headbolts. My concern came today when torquing down the bolts again, during the second and third sequence, It felt to me as though the same bolts (Long ones on turbo side) took less effort to take to 60degrees compared to the shorter bolts on the pushrod side. Are these bolts "Stretching" or is there a bigger problem here.

 

The threads do not feel stripped or damaged but its noticable and some bolts require less effort to get to 60degrees then others. The 100mm M12 bolts on the pushrod side took allot of force to pull to the final 60degs, I would estimate around 180nm to 200nm.

 

I may be being paranoid, but I would like someone to confirm. Do all the head bolts take a similar force to torque or are they all different?

 

Hope my explination makes sense.

 

 

IMG20210121130512 (Medium).jpg

IMG20210121143416 (Medium).jpg

IMG20210121124002 (Medium).jpg

IMG20210121124005 (Medium).jpg

IMG20210121124013 (Medium).jpg

IMG20210121124138 (Medium).jpg

IMG20210121124333 (Medium).jpg

Edited by youngengineer
Link to post
Share on other sites

If it makes you feel any better, you aren't the only one on here to have had a very quick MLS failure on a 200TDI -@western was the same, and swapped to composite like you.

As for the force required to stretch the bolts, if you think about it a shorter bolt will require more force, as you are stretching a shorter amount of bolt, though I can't say I have ever noticed it to be honest.

  • Like 1
Link to post
Share on other sites

I've heard of several people having issues with MLS which is why I swapped to comp. I find it a design flaw that they don't seem to put any of the coating between the laminations, surley this would provide a route for gases/liquids to escape through tiny imperfections.

 

What you have said makes sense about the bolts. The longer bolts do feel elestic compared to the short ones. 

Edited by youngengineer
Link to post
Share on other sites

As Bowie69 has mentioned me, The MLS head gasket I fitted to a checked flat head & block, after a week or so I found oil was getting into the coolant, after another head removal & buying a Elring composite gasket, flushing the cooling system, washing out the header tank & heater matrix, the head went back on & the Elring gasket cured the oil/coolant mixing, So now I won't touch those MLS gaskets,

I found oil between the MLS layers & some traces had made their way to one of the coolant channels. 

  • Thanks 1
Link to post
Share on other sites

The four bolts on outside of the manifold side of the head are narrower than the others as well, M10 instead of M12, so they take noticeably less torque to get to the final angle.

Edited by mat2495
  • Thanks 1
Link to post
Share on other sites

With water migrating about, have you properly dried out the threaded holes for the head bolts ? Water doesn't compress very well and can lead to erroneous torque readings.

Mo

  • Like 1
Link to post
Share on other sites

If the bolts feel strange then for the price of a new set, I'd be investing in some new from a reputable source - I'm sure I've read that they are re-usable a specific number of times but again for the faff - of having to replace if not quite right, I tend to always fall on the side of caution. 

Not head bolts but I have had experience of high tensile bolts stretching.

  • Thanks 1
Link to post
Share on other sites

Turners use Elring gaskets on their engines (I asked) , though I am with the OP in that in theory at least the MLS should last better and withstand more boost; Reinz offer some diagostics...https://www.victorreinz.com/en/service-downloads/practical-information/mls-cylinder-head-gaskets-and-damage-analysis.aspx?region. Maybe if you do try MLS again try a different brand? I think the best thing is to change the Elring one every now and again or something like that. Re the bolts, they do feel terrible when tightening. I use a wee bit of moly grease under the heads to try to make things a bit smoother

  • Like 1
Link to post
Share on other sites
2 hours ago, Mo Murphy said:

With water migrating about, have you properly dried out the threaded holes for the head bolts ? Water doesn't compress very well and can lead to erroneous torque readings.

Mo

I blew out all of the threads with compressed air.

Link to post
Share on other sites
2 hours ago, Maverik said:

If the bolts feel strange then for the price of a new set, I'd be investing in some new from a reputable source - I'm sure I've read that they are re-usable a specific number of times but again for the faff - of having to replace if not quite right, I tend to always fall on the side of caution. 

Not head bolts but I have had experience of high tensile bolts stretching.

I did use brand new bolts this time round. The first time round I used the ones I had which could have been quite old.

Link to post
Share on other sites
4 minutes ago, youngengineer said:

I blew out all of the threads with compressed air.

Yup me too but then I followed up with tightly twisted blue roll down each one and finished with a cotton bud. They all got water out.

Mo

Link to post
Share on other sites
18 hours ago, cackshifter said:

Turners use Elring gaskets on their engines (I asked) , though I am with the OP in that in theory at least the MLS should last better and withstand more boost; Reinz offer some diagostics...https://www.victorreinz.com/en/service-downloads/practical-information/mls-cylinder-head-gaskets-and-damage-analysis.aspx?region. Maybe if you do try MLS again try a different brand? I think the best thing is to change the Elring one every now and again or something like that. Re the bolts, they do feel terrible when tightening. I use a wee bit of moly grease under the heads to try to make things a bit smoother

The instructions that came with the Elring gasket were pretty good. They noted that both the threads and heads of the bolts should be lubricated. Anyway, yes I agree. I think the issue may not be "MLS" in itself but the variation in quality between manufacturers. I believe MLS style gaskets have superseded comp and Land Rover now only provide MLS for the 300TDI?

 

I wonder if all of the reported MLS failures have been Britpart or Bearmach gaskets? Has anyone had an actual Victor Reinz MLS fail?

Link to post
Share on other sites

I can't remember what make my MLS gasket was, but I will not use one again, hopefully my cylinder head won't need to be removed again. The current composite gasket came from Turners & it's a Elring. 

Good to read the problem has been cured. 

Link to post
Share on other sites
34 minutes ago, western said:

I can't remember what make my MLS gasket was, but I will not use one again, hopefully my cylinder head won't need to be removed again. The current composite gasket came from Turners & it's a Elring. 

Good to read the problem has been cured. 

What?! I was looking forward to your 1 million mile 200Tdi rebuild! :lol:

Link to post
Share on other sites
1 hour ago, monkie said:

What?! I was looking forward to your 1 million mile 200Tdi rebuild! :lol:

Engine had a full rebuild 2 years ago, so the next work on it will be a scheduled timing belt change. 

Link to post
Share on other sites
6 hours ago, Sigi_H said:

I saw on the pic the isolation of your bulkhead. What did you use? Is it self adhesive?

Yes its 10mm foil lined closed cell foam insulation. It makes a huge difference to noise levels in the cab, I think a roll is around £10 on ebay.

Link to post
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.

×
×
  • Create New...

Important Information

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