daftpooly Posted July 12, 2009 Share Posted July 12, 2009 Hi guys, the project eventually started today with stage 1 being a top end rebuild of my 3.9 auto Disco . The bad news is a previous muppet owner seems to have had one head off too and in the process didn't evenly torque that head, used a wonderul combination of bolts and left out gaskets, washers, etc. Even worse one of the head bolts has snapped , which raises 2 questions:- 1. The bolt in question is on the bottom bank of four, now i know later engines didn't use that row of four bolts, so can i take the risk of putting the head back without this bolt . Which leads me to the second question. 2. If the response is an overwhelming no, what's the best method of getting the snapped bit out, bear in mind that the car is on my drive and i don't really want to take the block out . One final thing, the shoppong list is of course growing, does anybody have a pair of exhaust manifolds, the originals have lovely cracks and a bottom cover for the flyheel, mine's missing and i don't think exposing the flywheel will be any good when i get it wet. I'm in the Northe East if that helps. Thanks in advance guys. Quote Link to comment Share on other sites More sharing options...
BogMonster Posted July 12, 2009 Share Posted July 12, 2009 How far down has the bolt snapped off - right in the block or is there / will there be some sticking out? (have you got the head off yet?) I wouldn't put it back on without all the bolts as the manufacturer intended - just as a general mechanical principle - but I don't know the specifics of whether it might be OK on a V8. If the head has been torqued up stupidly I'd also suggest you check it to make sure it is still the right shape when you get it off... Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 12, 2009 Share Posted July 12, 2009 Lucky boy - you can completely live without it if it's the lower row, they are actually deleted on the later blocks. The advice from some people is to refit the bolts but only torque to ~20lb just to keep mud out of the holes Here's my 4.6 block, look ma no bolts! While you're pulling things apart, I'd put later composite gaskets on (head & valley), and if you're feeling flush ARP head studs (as seen in my picture) mean you avoid the issue of snapping bolts in the block as you wind the stud in under very low torque, and then put the head on and tighten down with nuts & washers which means you're tightening a steel nut on a steel stud not a steel bolt into an alloy block. Quote Link to comment Share on other sites More sharing options...
daftpooly Posted July 13, 2009 Author Share Posted July 13, 2009 How far down has the bolt snapped off - right in the block or is there / will there be some sticking out? (have you got the head off yet?)I wouldn't put it back on without all the bolts as the manufacturer intended - just as a general mechanical principle - but I don't know the specifics of whether it might be OK on a V8. If the head has been torqued up stupidly I'd also suggest you check it to make sure it is still the right shape when you get it off... Luckily the head is flat, how I haven't a clue, but i was worried when it was coming off. The bolt has snapped flush with the block. Quote Link to comment Share on other sites More sharing options...
daftpooly Posted July 13, 2009 Author Share Posted July 13, 2009 Lucky boy - you can completely live without it if it's the lower row, they are actually deleted on the later blocks. The advice from some people is to refit the bolts but only torque to ~20lb just to keep mud out of the holes Here's my 4.6 block, look ma no bolts! While you're pulling things apart, I'd put later composite gaskets on (head & valley), and if you're feeling flush ARP head studs (as seen in my picture) mean you avoid the issue of snapping bolts in the block as you wind the stud in under very low torque, and then put the head on and tighten down with nuts & washers which means you're tightening a steel nut on a steel stud not a steel bolt into an alloy block. Thanks for that, now let's see how much ARP head studs are. Quote Link to comment Share on other sites More sharing options...
steve_d Posted July 13, 2009 Share Posted July 13, 2009 ........now let's see how much ARP head studs are. No matter what they cost they are worth doing. Steve Quote Link to comment Share on other sites More sharing options...
pw8757 Posted July 13, 2009 Share Posted July 13, 2009 I'm near Bedale and have a nearside exhaust manifold if you want it - I bought a pair on Buy Bay when my offside one had cracked. PM me if you are interested and I'll call you............................. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 13, 2009 Share Posted July 13, 2009 Real Steel had ARP head studs for £80 last time I looked, they have two different sets (the other is more money), I assume one comes with the outer 8 bolts and one doesn't. They also have lovelies like duplex timing chains (see my piccy) and rubber rocker cover gaskets which actually seal properly. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.