11 or 12mm head bolts?

[jwspin]

im rebuilding a solid lifter 1.6d from a rabbit and im wondering what head bolts to order. how do you tell if they are 11 or 12 mm?

thanks
-jared

[Wingaman]

Measure it with a caliper !

[Turbinepowered]

Do you have a gasser block handy? If your headbolts thread into the gasser like they belong, you need 11mm headbolts and should seriously consider upgrading to head studs while you're in there.

1.6 diesels were only 11mm for one year, and not even the full year at that. 1981 was the only year for 11mm 1.6 headbolts.

[Rabbit TD]

Do yourself a favor, in fact a lot of favors by switching to ARP studs weather they are 11 or 12.  The studs screw in a lot deeper and torque a lot smoother and eliminate a lot of problems, especialy if you have the 12's which are those pain in the ass stretch bolts with all those extra turns you have to put on and all the creaking that goes along with it making you always wonder if the block cracked in the process.  I'd have bougt them years ago if I had known about them sooner and these little engines are very sensitive about leaks even with a flat block and head, clean and torqued right.  I would say those studs, the exhaust spring clamp tool and the timing dial indicator are must haves if you are gonna play with these little beasts.  I'm surprised I haven't worn the threads out on my dial indicator as much as it gets used anymore and I thought I'd only need it just that 1 time {WRONG}

[maxfax]

11mm head bolts have an allen head (10mm to be exact), 12mm bolts have the tripple square head...

1981 is supposed to be the only year for a 1.6 to have 11mm bolts, but I've found them in some 82's as well..

Eaither way, get head studs!!!   They are required on a 11mm engine, the noise Rabbit TD described as soundling like the block cracking is indeed the block cracking with 11mm bolts...  Never ran into too many 12mm blocks cracking, but it's still HIGHLY recomended to go with head studs...

and I thought I'd only need it just that 1 time {WRONG} 

But the question is, was it because you can;t leave one engine alone, or you ended up with 12 more of these things?

[maxfax]

Good point!!!   Although you probably encountered the same thing I have, someone put gasser bolts in a diesel..  All the vendors I;ve checked out only list a 10mm allen head non stretch bolt for the 11mm diesels.. I've had parts guys hand me gasser bolts for a diesel a time or two as well..

The gasser bolts seem like a good option in that they thread in further, but they still don;t hold so well...

[79rabbit4dr]

im rebuilding a solid lifter 1.6d from a rabbit and im wondering what head bolts to order. how do you tell if they are 11 or 12 mm?

thanks
-jared

check page five of my thread (below), I just went through the exact same thing. I've got pix and part numbers listed there. PM me if you have questions, hope it helps!
http://www.vwdiesel.net/forum/index.php?topic=17027.60