As mentioned in a earlier post I have a head gasket to do, I have a couple of questions firstly following a thread on here head gaskets from Paddocks have been known to delaminate and fail and what is the best one to buy, there are also dfferent thicknesses what one do I need, I have a 95 300tdi ES and there is also mention of 2 or 3 hole gaskets whats the difference and which one do I need and lastley do you really need new head bolts. thanks
Fur Trapper
Banned
Yes they stretch when you torque them done. They go into a blind hole and can bottom out and give a false torque reading,ie; the head gasket did not get compressed properly, even though the torque was right.
All the work to due a head gasket job worrying over 25quids or less for head bolts?
jamesmartin
Well-Known Member
as said no of holes denote thickness of gasket as pistons protrude above block face it is critical to fit either same as was fitted (holes are visible with head in place on drivers side rear of engine ) or 3 hole as most fit to be safe , you can reuse bolts although if you want new bolts fit genuine as the onlt time ive snapped a bolt has been with new but of questionable origin ,as first stage is 40nm you need torque wrench but as stage 2 and 3 are 60 degrees you can use bolt flat as guide mark one edge and bring next edge to that mark ,a good marker pen etc is necessary to mark each bolt as you progress as you cant go back and check like you can with torque wrench,stage 4 is to give further 20 degrees to 10 bolts that surround cyilnders
storm99
Spreading Joy & Harmony
shocker
Well-Known Member
Workshop manual says 5 uses out of GENUINE LR bolts.Personally my experience is that you have more to worry about them snapping than bottoming.That or jamming on crap in the threads or down the holes giving you false torque.
Make yourself a thread cleaning tool by hacksaw cutting a couple of slots up the shaft of the two sizes of old headbolts,at right angles to the tread as it were.Run them in and out of each bolthole and clean the crap caught in the slots between each one using an old feeler gauge or similar.If there is stuff in the threads use a wire brush.Check for particles or fluid on each one and clear out as needed,blow out with an airline if you have one.
You shouldnt need any force to get the clearing bolts in and out,if you meet resistance theres a problem.You are not tapping a thread,simply cleaning whats there.So....DONT force them !
When you come to put the bolts in proper,smear a LITTLE clean engine oil across the threads,you really dont need a lot but you are more likely to get proper torque that way.
The holes in the gasket are referring to its thickness.Different thicknesses are needed (partly) to allow for piston crowns standing proud of the block.If you havent had a headskim (not you personally!) and there have been no serious overheats or similar problems I am reliably told that you fit a gasket of the same holes as the one that came off...the more holes,the thicker.If in doubt go for a 3 holer,1.6mm gasket.
You might want to do some searches on here if you are still unclear,or just look at some of my more recent threads about my own 300tdi head and gasket problems and the excellent advice that I was given,theres a wealth of anecdotal knowledge on these pages that is worth a dozen books.More !
On the subject of gasket type or brand,independent LR dealers have had instructions to supply Multi Layer Shim types but on futher questioning this was under the assumption that a new head was being used.I have found that a re used head sometimes doesnt like this.Others swear by MLS gaskets and have no trouble with them.I just swear AT them. I now use ELRING brand composite headgaskets for the 300 and find them a little more forgiving....unless you fit them backwards,like I did recently.I can be a stupid cnut at times.
Theres lots of tips on fitting the head here in various threads plus the 300tdi engine section that I know you have posted on before,Too much to list now,but have a good read and poke around the engine bay to familiarise yourself and come back with any worries.I know I always do.Good luck mate and tell us how you get on.
Shocksi.
PS and dont let paddocks fob you off with britpart ****,tell them if they havent got what you spec NOT to repace it with anything but genuine.At their expense,of course !
Make yourself a thread cleaning tool by hacksaw cutting a couple of slots up the shaft of the two sizes of old headbolts,at right angles to the tread as it were.Run them in and out of each bolthole and clean the crap caught in the slots between each one using an old feeler gauge or similar.If there is stuff in the threads use a wire brush.Check for particles or fluid on each one and clear out as needed,blow out with an airline if you have one.
You shouldnt need any force to get the clearing bolts in and out,if you meet resistance theres a problem.You are not tapping a thread,simply cleaning whats there.So....DONT force them !
When you come to put the bolts in proper,smear a LITTLE clean engine oil across the threads,you really dont need a lot but you are more likely to get proper torque that way.
The holes in the gasket are referring to its thickness.Different thicknesses are needed (partly) to allow for piston crowns standing proud of the block.If you havent had a headskim (not you personally!) and there have been no serious overheats or similar problems I am reliably told that you fit a gasket of the same holes as the one that came off...the more holes,the thicker.If in doubt go for a 3 holer,1.6mm gasket.
You might want to do some searches on here if you are still unclear,or just look at some of my more recent threads about my own 300tdi head and gasket problems and the excellent advice that I was given,theres a wealth of anecdotal knowledge on these pages that is worth a dozen books.More !
On the subject of gasket type or brand,independent LR dealers have had instructions to supply Multi Layer Shim types but on futher questioning this was under the assumption that a new head was being used.I have found that a re used head sometimes doesnt like this.Others swear by MLS gaskets and have no trouble with them.I just swear AT them. I now use ELRING brand composite headgaskets for the 300 and find them a little more forgiving....unless you fit them backwards,like I did recently.I can be a stupid cnut at times.
Theres lots of tips on fitting the head here in various threads plus the 300tdi engine section that I know you have posted on before,Too much to list now,but have a good read and poke around the engine bay to familiarise yourself and come back with any worries.I know I always do.Good luck mate and tell us how you get on.
Shocksi.
PS and dont let paddocks fob you off with britpart ****,tell them if they havent got what you spec NOT to repace it with anything but genuine.At their expense,of course !
jamesmartin
Well-Known Member
how many have you done
jamesmartin
Well-Known Member
shocker id forgotten about making your own thread chaser as i have bought ones but tis very good idea wish id remembered, as good a bit of advice i seen for a while
shocker
Well-Known Member
Coming from you James that is a real complement,thank you. I cant really claim to be the inventor,my old dad,60 years on the diesels, taught me that one !
One of the benefits that I see over using a tap type chaser is that one is less likely to damage the bolthole thread....cheaper too ! I have a drawer full of them for various engines that I have done over the years but always try to use the ones that came from the same engine type rather than relying on the thread designation (M8, AF,whatever) to allow for minor differences in the manufacturers tooling.
One of the benefits that I see over using a tap type chaser is that one is less likely to damage the bolthole thread....cheaper too ! I have a drawer full of them for various engines that I have done over the years but always try to use the ones that came from the same engine type rather than relying on the thread designation (M8, AF,whatever) to allow for minor differences in the manufacturers tooling.
