Does my Td5 have a blown headgasket?

[Hendrik]

Hi all
Something that has been bothering me for a while. Everytime I start up my D2 (99 model), and take off there is a bubbling sound just above my feet, so clearly theres air in the cooling system. Now I've tried bleeding numerous times to no avail. The bubbling sound gradually started, as in it did not start to occur after a coolant change.
In addition to this, after the engine has been at operating temperature and turned off , and when the expansion cap is turned anticlockwise, as to loosen it, coolant starts pouring out of the overflow pipe. My question is, is it normal for the system to be that pressurised? The coolant coming out of the overflow is very bubbly so there is clearly air in there.

I have overheated it before when a coolant hose busted, but everything seamed fine and the bubbling sound only started about a year later.
This whole thing has me very concerned, as I have a week long trip coming up and would not like to take a car that I am not confident in.
Your advice would be much appreciated. I really don't want to ruin the current head.

[strangy]

Hi Hendrik, I am in the middle of doing my head gasket now. I have had two instances of coolant dumping after towing a trailer (not real heavy) and some off road work. The low coolant alarm let me know which saved a bigger issue. Prior to this I noticed significant pressure in the header tank when removing the cap and the coolant going overboard. Symptoms as you describe. The motor ran ok but I had noticed it running slightly rough at idle. I had my sons D2 to compare with after the same trip and his had much less pressure, what I would consider normal. Anyway I got the head off and the plastic dowels had sheered off and there was evidence of blow by around the #3 cylinder and coolant gallery also some movement around #5. The head has not warped and will be crack and pressure tested today. I think I have gotten off lightly compared to some here. It seems my sort of failure is quite common, compression test(AFAIK you cant check compression on #5 as there is no glow plug hole to screw a fitting into.)
& testing for exhaust gas contaminants in the coolant may reveal something futher for you. Though I had done neither of these before stripping the head as I was positve of my problem. I did not have the bubbling sound and mine has not been overheated.
If it were me I would be pulling it off as it has been overheated and the symptoms match. Would you do this yourself?

On a positive note this motor is the easiest head gasket Ive done compared with some Toyo and Mitsi motors.

Hope this helps

Cheers

[Psimpson7]

Hi Hendrik,

They do run quite high pressure in the cooling system, but yours does sound excessive. The D2 cap/overflow is slightly different to the Defender, but we noticed a tiny leak past the cap on 3 seperate occasions so I pulled the head after posting a similar thread on here.

I also was nervous about making the issue worse, and decided it was safer to do it before the issue got worse.

Difficult one to call as to whether you should use it. Where are you going? Is it remote? do you have a low water alarm.

Its not that difficult to do. I agree with Strangy, easiest one I have done

Rgds
Pete

[Hendrik]

Thanks for the replies.
I'm going to Fraser for a week, and would hate to be stranded in the middle of a sand island with a cracked head. I think it would be best if I did something about it now, before it is too late. Strangy, I think the my dowels would be shredded off as well, due to the over heating. And the excessive air in the system would clearly cause hot and cold spots in the head. Now that you mention rough running, it sorta feels like mine has been getting worse, when compared to other td5's.
I think I should just do it, before I do too much damage to the head. I will be doing it myself, Pete I've looked through your write up and it doesn't seam too difficult. I will get my dad to help me as well, he has done heads on countless diesels, as well as a few 300tdi's. I think it could be done in about a week, if I was only to spend my free time on it, it seams simple...but then again nothing is ever as simple as it seams.

[Psimpson7]

Hey mate,

You should easily cope with getting it done in a week.

Do you have a good head shop to get it checked/skimmed at?

Feel free to ask any questions.

LR Gold Coast should have all the parts in stock.

Rgds
Pete

[Hendrik]

Hi Pete
I think it would be easy enough to find a place to do it. Apart from cleaning and pressure testing the head, did you get the injectors cleaned as well?
It would be good to do a few other things as well while I'm there, like cleaning out the inlet manifold and also checking for broken exhaust manifold studs etc.
Kind of looking forward to doing this, it will run so much better with a new head gasket. Will also fit a low coolant alarm when I'm done, so I can be warned when another hose busts.

[Psimpson7]

I didnt have the injectors cleaned no, I didnt do a valve grind either, but at the time my car hadnt quite done 100k so it may be more worthwhile on yours.

Rgds
Pete

[abaddonxi]

The Td5 head thread-
http://www.aulro.com/afvb/projects-tutorials/66259-td5-cylinder-head-removal-how.html

[Hendrik]

I didnt have the injectors cleaned no, I didnt do a valve grind either, but at the time my car hadnt quite done 100k so it may be more worthwhile on yours.

Rgds
Pete

I think I will look into getting that done as well, mine has done a lot of kms.
With the machining, did you just take an absolute minimum off and hoped that it was enough? Reading other posts, it seams only a very small amount can be skimmed off. Won't know for sure untill I have it off, but I just don't want to get the head machined, put it back only to find out that it wasn't enough and having to replace the head anyway.

Will start looking at what parts I need today.

[Psimpson7]

I had the minimun needed to lean it up taken off. That was from memory 6thou. 8 or 9 seems to be about the most you can take off.

The head place will know exactly what they are doing. You will be able to see what it looks like. They wont, not take off enough.

Mine was done by P+A Gilberts in Southport who also did our Vitara, and they are excellent.

Rgds
Peter

[strangy]

Hi Hendrik, the tutorials here are simply fantastic, between these and the RAVE CD or manual, you will certainly nail it in a week. I was surprised how fast and easy this job has been. I started at 0900 and by 1300 had the whole lot off and stripped ready for the machine shop and I took no shortcuts. If you have successfully done a head gasket before on any vehicle, you will have no more effort for this.

I'm expecting it back tomorrow, which gives me time to clean up the block, fit the new washers and o rings to the inectors and fit the EGT probe to the exh. manifold.

I was not going to have the injectors cleaned as the spray pattern on the piston crown is clean and uniform.
Having originaly being told the units could be cleaned, I am now told no one can test them and the only cleaning that can be done is from the outside and you could do that yourself with a soft brush.

I am expecting about $160 for the test and grind. I discussed the hardened / throwaway head. Ive been advised they have machined more than 60 Diesel Hardened Alloy Heads from Toyo, Mitsi, Isuzu and Landy, all without ramification. According to them the main reason manufacturers say throw away is, when the head cooks up badly the warpage is too great to machine out leaving sections too thin, futhermore when the head warps that badly cam journals are no longer parallel and then shafts break etc. Most Ally heads cant take much more than 10 thou.

Futhermore the distance between centres of the camshaft and crankshaft is reduced requiring the timing chain tensioner to take up more slack and since the chain is of specific dimensions correct timing may be unachievable. Which is also one of the reasons why vernier camshaft pullies are found on modified engines.

At least if it is beyond repair Turner Engineering are offering full reco for $2500 AUD ( im pretty sure this included valves) A bare Hi lux or Isuzu head is more than $3000.

Good luck with it.

[Hendrik]

Thanks Strangy
Are you going to fit steel dowels from LR, as I have heard things like fitting the wrong steel dowels could crack the head? Also did you get the valves grinded, as it might be something I will have to consider due to the amount of kms mine has done.
By the looks of things, there are not too many things to remove to actually take the head off, just have to take your time I guess and make sure things are well organised.

[johnclv]

Mine used to "gurgle" away all the time - Head gasket was about the only thing that did not fail on the POS

Anyway - I have a ( comprehesive )head kit and other goodies that I am wanting to sell as I no long have my POS.

PM if you are interested. I am about to put it all up for sale on ebay on the weekend

Cheers

[strangy]

Thanks Strangy
Are you going to fit steel dowels from LR, as I have heard things like fitting the wrong steel dowels could crack the head? Also did you get the valves grinded, as it might be something I will have to consider due to the amount of kms mine has done.
By the looks of things, there are not too many things to remove to actually take the head off, just have to take your time I guess and make sure things are well organised.

Steel dowels, yes. IMO and from a design view, the dowels really are a location device to ensure the head is aligned correctly with the cylinders, gasket and block. The head is retained by the bolt clamping force, not the dowels. I feel my type of gasket failure is not based on the type of dowel , but due to either poor bolt quality or torque setting at the factory level. With bolts stretching and losing there tension over time/use. Of course with severe heating it doesnt matter what bolts/ torque you had.
LR steel dowels are reccomended by TRS and many others for all engines.
However, again IMO, steel dowels will assist the head to stay in place at the upper end of pressure and heat if the bolts have tendancy to lose tension and will reduce the amount of potential failures. If the head has expanded and moved enough for the steel dowels to cause cracking, then the head will be useless regardless.

Valves, no. 220km on mine. No signs of abnormal wear and doubt any issues will arise here. There are hone marks still in the bores!

[Psimpson7]

I used genuine LR steel dowels without issue.

[Hendrik]

Thanks for the detail Strangy, very helpful.
If thats the case, I will go genuine LR dowels, infact thinking about going genuine LR for everything.

[Shamo]

Kind of looking forward to doing this, it will run so much better with a new head gasket. Will also fit a low coolant alarm when I'm done, so I can be warned when another hose busts.

Why don't you just watch you're temperature guage?

What's so good about going genuine? the label?

Shamo

[Psimpson7]

Because the gauge isnt a live reading as such. there are basically only 3 readings. cold/normal/hot and by the time it moves you have generally done the damage.

Non genuine parts can be fine, unfortunatley they can also be absoloute junk.... I know which one I would use!

[justinc]

Because the gauge isnt a live reading as such. there are basically only 3 readings. cold/normal/hot and by the time it moves you have generally done the damage.

Non genuine parts can be fine, unfortunatley they can also be absoloute junk.... I know which one I would use!

And genuine parts aren't all that costly, when you figure in the labour attached to the job. It's All I ever use doing these jobs, genuine LR or Elring for gaskets, and SPS for fasteners.

JC

[Hendrik]

Well the head will be coming off this weekend, or I will try to make a start at least and see how far I get. Been looking at Rave and Pete's write up, and know how I will go about it. Will post updates as I move along.