Thread: Which head gasket for TD5

There is a section of the gasket visible with a punching,it tells you wich gasket is needed,the VIN will not.
See what others say,I did order a gasket for mine,but was told by the mechanic wich thickness was required.
Andrew

The head gasket has holes to dictate the thickness, you need to look at the one on there to begin with and order the same. Don't forget head bolts.

JC

okay thanks, how can i tell what head gasket i need before i take it off as i want to have all the parts ready before i do it, i have ordered the head bolts, and the vrs going by the vin, if its not the right gasket in the set when it comes ill just have to get the right one, any ideas how much they are form genuine? and a few other odd and ends like the injector loom, thermostat and waterpump and ive ordered some silicone hoses and egr removal kit, do i need to replace the bolt for the cam sprocket and bolts fro the rocker assemblies?

Front right hand (when looking in) side of the head under the water inlet. you will see the part of the head gasket with the holes. You may need to clean up a bit.
If you have 1 hole your replacement should be a 2 or 3 hole.

I was told by TRS that they only supply 3 holes regardless.

I had a 2 hole gasket in the first place, so 3 was the replacement.
The thickness of the gasket on the TD5 is important to keep the timing correct and chain tensioner within an effective working range.

cheers

When I ordered my head gasket through M.R. Automotive, they also said that they only supply the 3 hole (thickest) one. Mine was a 2 hole gasket.
The 0.8mm difference doesn't make a huge difference to the cam timing - a little advance can be a good thing for mid range.

The different head gasket sizes will have no effect on cam timing, there is a pin to lock cam and another to lock crank. You leave cam sprocket bolts loose fit tensioner and the torque cam sprocket bolts. Doing it this way the cam will always be in the same position, regardless of head gasket thickness.

The different head gasket thicknesses is for piston protrusion, If you measure how much the piston lifts above the block deck height. This determines the thickness of head gasket.
If you are not getting any machining done, use the same size gasket (same number of holes) If machining use thickest gasket.

The different head gasket sizes will have no effect on cam timing, there is a pin to lock cam and another to lock crank. You leave cam sprocket bolts loose fit tensioner and the torque cam sprocket bolts. Doing it this way the cam will always be in the same position, regardless of head gasket thickness.

The different head gasket thicknesses is for piston protrusion, If you measure how much the piston lifts above the block deck height. This determines the thickness of head gasket.

Sorry while correct this is not quite accurate and cannot be used as a general rule.

Machining the head changes the distance betwen centres for the cam and crankshaft. You may lock the camsaft and crankshaft but,
the Timing chain pitch remains unchanged therfore you now have extra slack for the tensioner to deal with on the unloaded side and a retarded state of timing on the load side. The slots in the cam gear will compensate for the difference and achieve correct timing if you have fitted the appropriate gasket after machining. The extra slack on the unloaded side will generally be taken up by the tensioner, but in some instances the tensioner will reach its limits before the chain has actually reached its limit (unlikely but possible).
Piston protrusion has no part in this case. You do not change this on this motor. By machining the head you will decrease the clearance between open valve to piston by the amount of machining. Piston protrusion is unchanged as it is relative to the block and the combustion chamber is in the piston not the head.
If the gasket selection was based soley on piston protrusion there would be no need or reccommendation to go to a thicker gasket after machining.

If you were to take the accepted maximum from your head of 8 thou and your original gasket was 2 or 3 holes and you then fitted a 1 hole gasket. You would unlikely have adjustment enough to achieve correct timing.

If you are not getting any machining done, use the same size gasket (same number of holes) If machining use thickest gasket.

Do not fit a new gasket to a TD5 without machining the head to remove the grooves made by the gasket fire rings.
You will simply waste your time and money.

The 0.8mm difference doesn't make a huge difference to the cam timing - a little advance can be a good thing for mid range.

A little advance or retard in valve timimg is not the same thing as for ignition or fuel pump timing and is not a good thing for these motors..
The ECU is looking after any of the fuel aspects and is conditional on the mechanical timing of the cam shaft corresponding to the CPS signals for the EUI to function properly.

This is why vernier cam gears are used on performance and modified motors to correct changes caused by modifying and or machining.

cheers

Just to add what Strangy says, set up the valve timing using the corect crank and cam locking tools and procedure, and all will be fine. They DO NOT like excess advance or retard.

It just has to be right

JC