300Tdi 'no notch' head gaskets

[rednaxela]

Were the 'no hole' head gaskets ever factory fitment by Land Rover?

If not, why are they an option, and why would a mechanic use one, if following the simple approach of using the same type as that which was removed.

Surely anyone replacing a HG on a TDI should know that skimming the head is irrelevant for HG thickness?

 

 

[monkie]

Why are you asking? Are you having some work done and you don't think it is being done right? The no hole head gasket for a 300Tdi is listed as a part number (ERR7154, now LVB500230) but I don't know if it was fitted as standard by land rover. I have always understood that the head gasket thickness is determined by measuring piston protrusion on a Tdi.

[cackshifter]

You might fit pistons that were slightly taller I guess is the official answer. If you have to skim the block it might be handy too. 

[Troll Hunter]

In practical terms, what is wrong with fitting the thickest gasket regardless of what gasket came off? This way you know that the head is clear of piston contact, and yes, you will lose a little compression ratio, but is this a practical concern?  Of course, if the block is skimmed then piston protrusion must be measured on each piston to ensure that that the gasket protects against contact.

Mike

[rednaxela]

I'll soon want to install a new ported cylinder head and was set on ordering a 3 hole gasket as that's what I thought my 90 had, but went out to double check and saw it was a no hole gasket. Most seem to imply that 3 holes is thick enough if in doubt, although I will certainly measure the protrusion. To reduce down time I could always order two gaskets, and never bother to return the unused one and add it to the dusty heap of unused gaskets and fasteners and bits of junk. 😙

 

Engine is at 102k miles. Had it done a stratospheric mileage, I could understand that the block etc could have had some work done necessitating the thicker gasket.

 

 

 

[Snagger]

If you have the block deck skimmed because of heat distortion or corrosion, or if you replace the crank shaft, pistons or rods with a result of the piston crowns sitting any higher than before, then you’d need a thicker gasket.  Just having higher mileage shouldn’t cause that change, though any significant wear on the crank, gudgeon pins or their bearings could allow the piston to move up higher on the upstroke (very unlikely with the gas pressure above).  

A head skim could also need a thicker gasket if the valve seats weren’t cut by a matching amount.

Three holes gaskets are the most common, but they are not “standard” as such - all four thicknesses are standard spec, just allowing for tolerance variations.  You can fit the no-hole gasket without worry; the engine will run fine and any performance or economy loss will be minimal.  It could conceivably make cold starting a little harder, but that’d only be exacerbating a different fault that is causing the starting difficulty in the first place.

[Will@LRW]

I dug out the technical service bulletin for it if you're interested

[rednaxela]

That's very helpful guys, thanks Will also; my 300 is quite a late model - that could explain it.

[missingsid]

Wow, have I got this right? I can't believe even for LR that build quality got so bad that the piston height changes that much and that the fix is to bodge it not reject!

Or is this a diesel thing?

[Troll Hunter]

Is this a Land Rover manufacturing defect?  Who actually makes the 300Tdi, is it LR or some sub-contractor?

Mike

[western]

LR made the original 300tdi engines,  which was sold on to Brazil after the Td5 took over as the standard Defender engine,