Thread: Td5 - to steel dowel or to not steel dowel

Originally Posted by RRV80

Hi all, mid way through doing preventative headgasket maintenace, i thought originally that if it had plastic dowels always replace with steel, now i have read in a manual certain vins must under no circumstances be fitted with steel dowels, i have the steel dowels ready to put in, i have not checked the numbers yet to see if im supposedly allowed to fit steel dowels or not, do i go by the reccomendations and refit plastic if my vehicle falls before the vin listed or fit steel regardless?

If it has plastic dowels then leave them in. The dowels are for assembly only. ie. they hold the gasket and head in the correct place while the head bolts are torqued down. Once the bolts are torqued down the dowels play no further part.
The time to pull a TD5 head and renew the gasket and bolts is when you appear to be topping up the water in the header tank more than normal. Let it go an extended time in this condition then you are heading for a good 'cooking'.
Regards

Well there is nothing left of the dowels, the plastic has disintegrated, i have steel ones and i have seen jc comment on forums thats all he uses just wondering if anyone has actually come across this head cracking that appstently can happen,

I used the steel ones on mine. No issues since.

Its your call but I personally would never use the plastic ones.

Thanks, just reinstating what i was thinking in the back of my mind

Our LR specialist has the change from plastic to metal dowells on a list of things he tells you to change on a disco 2 if it hasn't already been done. Along with greasible front drive shaft, sealed injector harness, oil pump bolt loctited, new o rings in the fuel cooler etc.

Our 03 D2 came with steel. Our 99 D2 now has brass?. Although I agree that once it's assembled and torqued down they should play no further part, but some people say the heads are known to move. I just can't believe they were plastic at all in such a hot place????

I checked the length last time I had the head off.
Think I had 1mm to play with and the fact the ends are chamfered(spelling,ron?) I was happy to use them.

I overhauled our head as a PM measure and replaced the plastic dowels (or what was left of them) with steel dowels about 18 months and lots of kms ago. All good thus far. The head must move under certain conditions for the plastic dowels to sheer as ours had. AFAIK I haven't overheated ours.

Erich

Have a read of this thread....

Who has fitted Steel head locating dowels (Td5)

Cheers
David


> > All td5 derivatives within VIN range
> > ds2 02 my 2A736340 - 3A793895
> > def 02 my 2A622424 - 3A647705
> >
> > Cylinder head locating dowels.
> >
> > Td5 engines fitted to vehicles within the above VIN range are fitted with
> > plastic dowels to locate the cylinder head onto the cylinder block.
> >
> >
> > LRE has intrduced steel locating dowels from the following VINs.
> > ds2 - 3A793895
> > def - 3A647705
> >
> > IMPORTANT
> > If a cylinder head is removed from a vehicle in the above VIN range, the
> > plastic dowels must be replaced with new spec steel dowels, which are now
> > available from LR parts.
> >
> >
> > CAUTION
> > TD5's prior to the above VIN ranges must not under any circumstances, be
> > fitted with the new steel dowels.
> > If steel dowels are fitted to earlier engines cylinder head cracking may result!
> >