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Mitsubishi L200 2.5D 2003 - Head gasket #

Posted by Bradley kingsley on October 9, 2012, 10:40 pm

Year of Manufacture *: 2003
Engine Size and Code *: 2.5 turbo diesel

Hi i done a head gasket and new head on this about 4 months ago.
It was in yesterday again with the customer saying it bubbles into the expansion bottle.

He is right it is.!!

At idle you can see after a few minutes it will give a few bubbles every now and then. It hasnt lost water and runs absalutly fine.

I believe it wasnt a genuine gasket fitted could that be the big problem, has anyone else had this problem??

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by aidan birley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2879' width='330' height='300' border=0 style='border:none;'> on October 9, 2012, 10:44 pm, in reply to "mitsubishi L200 2.5 diesel, Head gasket"
Aidan Birley

Bradley

These are also known for cracked head issues, They dont always show on pressure test or visible to eye.

cheers Aidan

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Tony Ludford <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5539' width='330' height='300' border=0 style='border:none;'> on October 10, 2012, 7:19 am, in reply to "mitsubishi L200 2.5 diesel, Head gasket"
Tony Ludford

Have you looked at the top of the radiator, where the rad cap seals onto it?

Last one I had, which took the head and gasket, the combustion gases had eroded the plastic. Needed new rad & cap too.

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Bradley Kingsley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3153' width='330' height='300' border=0 style='border:none;'> on October 10, 2012, 7:53 am, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Bradley Kingsley

Aiden thanks for response but it had a brand new head fitted with gasket.
I will hopefully get a look today and maybe get a dye test on it. I realise these have a egr cooler can these introduse gases?

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Russell Davey <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2748' width='330' height='300' border=0 style='border:none;'> on October 10, 2012, 9:43 am, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"

I've had the same as Tony - take a close look at the rad & cap.

Also, done around 20 ish head gaskets on these - have never fitted a genuine gasket - always aftermarket, so that shouldn't be your problem as long as the head has been tightened correctly

What sort of pressure do you have in the cooling system? Attach your pressure tester to it, run up to temp & post back the results.

Is that crank damper pulley ok? - had loads where its just about attached by the rubber bonding - no wobbles - no noise but unable to turn the belt to the water pump at sufficient speed.

EGR coolers are common too - bypass it & test vehicle.

Russ

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Simon Clarke <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3160' width='330' height='300' border=0 style='border:none;'> on October 10, 2012, 8:22 pm, in reply to "mitsubishi L200 2.5 diesel, Head gasket"
Simon Clarke

I did a head on one these after cambelt failure my local distributor supplied aftermarket head and it came with a full gasket set and timing belt etc. After about six months that too had combustion gases coming up through rad, I drained coolant and removed top hose at head and when started from cold you could see the gases,sure enough head gasket was leaking, I cant remember which brand of gasket was supplied with head but i replaced with a Payen one and all has been fine since

HTH
Simon

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Bradley Kingsley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3153' width='330' height='300' border=0 style='border:none;'> on October 10, 2012, 10:40 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Bradley Kingsley

Thanks for all the responses on this. I got it in this morning and drained some coolent from the rad then dye tested it,, bubbles within 2 mins and turned dye in about 4.

I then used a hose to bypass egr cooler and tried again with just the same results.

Head is off now and going for skim etc in the morning. I have ordered genuine gasket. Onto saxo head in the morning.(a paid job)

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by liam hall <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3033' width='330' height='300' border=0 style='border:none;'> on October 10, 2012, 11:10 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Liam Hall

Now this is an area I am very well versed on!

I currently have two L200's on the go, both engine out, crank, shells, heads etc.

The main thing, as always really is not necessarily using genuine parts (in the case of big end shells most definitely not genuine!), but to ensure you use a known brand, like mentioned, payen, reinz etc I have had no issues.

The aftermarket heads are good too, you all know that if a head is cracked its not a duff casting, its a coolant fault etc.

If any of you get one in for the dreaded knocking from big ends, feel free to contact me, I have some very good sources on parts, such as the early 4D56 crank which is better than the later, etc etc.

Liam.

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Alan Lange <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3293' width='330' height='300' border=0 style='border:none;'> on October 11, 2012, 9:47 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Alan Lange

I've also had the same problem as Tony but as you say the dye changes colour - have you checked the block face is true?

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Bradley Kingsley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3153' width='330' height='300' border=0 style='border:none;'> on October 11, 2012, 10:13 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Bradley Kingsley

Just got head back from being checked today.

They never charged us? Im wondering if they hadnt checked it for true before supplying it as they have gave it a skim now.?

Genuine gasket is all metal(multilayer) unlike non genuine.
thanks again for all your opinions.

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Kevin Apps <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2589' width='330' height='300' border=0 style='border:none;'> on October 12, 2012, 1:20 am, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Kevin Apps

Bradley.
"They never charged us? Im wondering if they hadnt checked it for true before supplying"

Why would they check a brand new head ?

Kev.

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by bradley kingsley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3153' width='330' height='300' border=0 style='border:none;'> on October 12, 2012, 10:18 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Bradley Kingsley

Kevin, do all new heads come machined absolutely flat?? I dont know. Probably do but have never questioned it.

Anyway got job done today and out the door.

2 more thoughts have came up about reason for failure,
Its a 2003 D4..T engine, sorry cant remember full code, But they fitted fibre gaskets up to 2002 i believe and multilayer steel from then on.

I was asked if it was fibre or steel when i fitted the first gasket and it had a fibre so we fitted a fibre type.

This time i gave the chassis number to main dealers and was supplied a multilayer.
I have noticed the sump has been off this before the first head was done, could it be it had a fibre gasket fitted before i ever saw it causing premature failure then i got the job to fix it?

Also 2 different way to tighten, torque or torque then angle. I done the torque then angle again today and then went over it at 124nm as the last torque stage is and found some moved up to 100 degrees further,??

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Kevin Apps <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2589' width='330' height='300' border=0 style='border:none;'> on October 12, 2012, 10:35 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Kevin Apps

Bradley.

"do all new heads come machined absolutely flat?? I dont know. Probably do but have never questioned it."

Yes, unless (maybe) if it,s a bare casing !

2003 should be torque and angle and i would have renew them (even if AD says its not needed. You could be getting it back soon.

Kev.

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by bradley kingsley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3153' width='330' height='300' border=0 style='border:none;'> on October 12, 2012, 11:21 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Bradley Kingsley

Kevin, As far as i know when this head was supplied it was supplied to the head technicions
as a bare casing and they swapped the cams and valves etc from the old one.
Also it did have new bolts this time and i did torque and then angle them!! But after doing the final 120 degree angle i checked how tight they were with the torque wrench set at 124nm in the advised sequence. I found that most of them did tighten a bit further still!!
124nm is the last sequence for the torque type sequence.

The way i see it the angle way left the actual bolts very uneven in torque when some turn over half a turn further than others. I can understand the reasoning with stretch bolts using angles but if these are stretch bolts why does it say they can be re-used??

Why should i be seeing it again soon Kev, what have i done to jeperdise the life of this head gasket?

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Kevin Apps <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2589' width='330' height='300' border=0 style='border:none;'> on October 13, 2012, 12:01 am, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Kevin Apps

Bradley.

"Why should i be seeing it again soon Kev, what have i done to jeperdise the life of this head gasket"

Well the bolts will be over stressed if they took more turning to reach the torque setting which is not applicable, WHAT tech specs were supplied with the new bolts as too torque setting/oiled threads and shoulders ?

I suspect they are stretch bolts !! and AD may have it wrong

Kev.

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Bradley Kingsley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3153' width='330' height='300' border=0 style='border:none;'> on October 14, 2012, 6:35 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Bradley Kingsley

Kev i dont agree with you on that one.

When i do a head gasket i always follow the same protacol.

1. remove head send it away for pressure check and skim.

2. remove dowels, clean head and check for true.Run all the bolts into the block with a little lubricant checking they run free all the way. Lube bolts and washers before refit.

3. clean both faces before refitting head using torque sequence and settings as manufacturers spec says.

But how do you believe strech bolts work??

I believe they stretch when under enough pressure to stretch. This would be when they are tight enough to stretch if as you say i have over stretched them(if they are stretch bolts that is?) Some of them were already overstretched before i added the final torque as they didnt move at all or they werent over stretched and i torqued the others that did move to the position where they are now stretching.
Right or Wrong??

Either way i believe you need all the bolts at the same torque as they are now.

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by aidan birley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2879' width='330' height='300' border=0 style='border:none;'> on October 14, 2012, 8:11 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"

Hi

Re stretch bolts, my opinion is that this is a slightly misleading description and it would be better to refer to them as > spring bolt < as it reflects there purpose.
However as they operate in there 'plastic' region this can result in a permanent stretch when tightened.

These type of fixing bolts will be relatively long and thin, the idea is that when correctly tightened it extends like a spring. The result is that when the head and gasket expand / contract/ settle in service the ' spring ' effect of the bolt maintains its clamping force.

The advantages are clear, no re torquing needed after running, clamping force maintained through operating temperature range.

Re torque / angle tightening. The sole point of tightening a fixing correctly is to obtain the correct clamping force Angle tightening does not automatically mean that the fixing bolt is 'stretch type '

The problem with traditional torque method is that it gives inconstant (clamping force) results as so much depends on condition of threads and shoulder i.e smooth / rusty / dry / lubricated.

As an example we will all be aware of the difference oiling the threads on a humble puller has.

Tightening by angle will give more consistent results as condition of threads has no effect, the clamping force being predetermined by the pitch of thread and type of bolt.

Agreed a pre torque is used but the % error on total clamping force will be much less.

cheers Aidan

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Bradley Kingsley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3153' width='330' height='300' border=0 style='border:none;'> on October 14, 2012, 9:46 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Bradley Kingsley

Thank you for your explanation there Aiden,

I agree with what you say completly. A good sound explanation.
The case in question is probably not fitted with stretch bolts as they are fairly short and thick, also AD says they dont need replaced(altho i did replace them to be sure)

I did run the bolts down the threads with lube first then placed gasket and head on replacing bolts with copper slip on shoulders and threads.

I used a nearly brand new snap on torque wrench for all the torques, a lot of questions remain i would like answers for.

Why AD says dont replace bolts when it gives an angle setting as you usually get with stretch bolts??

Why if you have set torques then angles all the bolts are then at varied torques??

I do get what you mean about setting a torque then an angle stretching bolts an exact amount due to thread pitch but whats to say the first torque is any more accurate than the last??

How much can the bolts be streched before they are over stretched, or how smaller stretch is to small??

If AD says dont replace bolts and you need to how much more info is wrong??

Just thoughts that bug me,,

King regards Brad

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Dave Hill <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2783' width='330' height='300' border=0 style='border:none;'> on October 14, 2012, 11:08 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"

Nice post Aidan.

Quote...

""but whats to say the first torque is any more accurate than the last??""

That is a good question Bradley.

The answer I believe is that the stresses that will influence the torque wrench "click off", that are imposed on the bolt are less at the lower torque range.

Take for example the effect of static friction.

I am sure that we have all experienced the loud "crack" that a head bolt makes when it subjected to the final stage of a tightening sequence. This loud crack is generated when the static friction threshold is surpassed.

If you think about the amount of effort required to start the bolt turning, in that final head bolt tightening sequence, compared to the effort required to start the same bolt turning, when it has only been tightened to 25 Nm, you then begin to understand why we now use a low torque in the first instance, followed by several angular tightening sequences.

I am sure that in the old days, there were many examples where technicians had inadvertently thought that the head bolt was tightened correctly, when in reality the bolt was not tightened optimally due to variations in technique.

This can be demonstrated nicely in the workshop, If you have a sacrificial car & the inclination to try it.

If you set your torque wrench to lets say 150 Nm & proceed to tighten a head bolt, you will see a significant difference in the final resting position of the bolt, depending on your technique. For example, if you perform the final tightening action, in one fluid movement, without pausing, you will find that the resting position of the bolt will be further (read tighter) than if you were to pause momentarily before the final 150 Nm torque wrench "click off" is heard. The momentary pause will often cause the torque wrench to "click off" prematurely before a further movement has taken place, giving an misleading indication that the bolt is tight enough.

On top of all that, imagine the influence of thread condition & lubrication used. Not all technicians apply the same standards. A tight thread & a dry head bolt washer will influence the final torque reading more so, when compared to a bolt that is tightened thus.....

25Nm
45 degrees
45 degrees
45 degrees

I hope that makes some sense.

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Bradley Kingsley <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3153' width='330' height='300' border=0 style='border:none;'> on October 15, 2012, 8:04 am, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Bradley Kingsley

Thanks Dave that all makes sense to me.

I do always pay special attention to the threads and the final turns of any bolts i torque making sure they are torqued in one smooth action as best as possible.
I dont believe in this case it was a big factor as they were not at the stage of cracking free when i gave them that last tweek.

anyway i guess time will tell??

Re: mitsubishi L200 2.5 diesel, Head gasket

Posted by Rob Nicholson on October 19, 2012, 10:47 pm, in reply to "Re: mitsubishi L200 2.5 diesel, Head gasket"
Message modified by board administrator January 25, 2013, 3:47 pm

"If you set your torque wrench to lets say 150 Nm & proceed to tighten a head bolt, you will see a significant difference in the final resting position of the bolt, depending on your technique. For example, if you perform the final tightening action, in one fluid movement, without pausing, you will find that the resting position of the bolt will be further (read tighter) than if you were to pause momentarily before the final 150 Nm torque wrench "click off" is heard. The momentary pause will often cause the torque wrench to "click off" prematurely before a further movement has taken place, giving an misleading indication that the bolt is tight enough"

Dave, A nice explanation of static and dynamic friction the force required to start and keep moving an object demonstrated (a few moons ago!) in a physics lesson attaching a newton gauge to a block and pulling along a flat surface the gauge rises then when it starts moving the force required to keep it moving reduces, and then if lube added...

Rob

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