I have a 66 425 MW that has a stripped headbolt thread in the block. The thread is at the 4 O'clock position on #1 cylinder (the long bolt). My ? is, is there enough meet to; 1) Drill out and helicoil 2) Drill deeper and cut more threads 3) are there any other options Thanx, Lou
Someone probably used a short bolt with the a/c bracket. If you have stripped the threads using the longer bolt, the only option you have is to use a heli-coil or use a stud driven down as deep as possible. I'd opt for the heli-coil, there should be enough space, but I have never had to do that.:bglasses:
Yea, thats exactly what happend. The meat around the hole looks thin and I was just wondering if anyone had drilled this area before
head bolt- Hi Lou-I'm not too sure there is enough 'meat' to go with a helicoil or keensert. I might try first to drill tap straight thru into the water jacket and then locktight in a stud. good luck!
Thanx Dan, If I depended on luck I would be in bad shape!! The meat around this bolt hole looks pretty thin and if it was weak after the helicoil job I would be afraid that the torque would crack it. Where's a good source for studs of different lengths?
Head Bolts These guys are the best. http://www.arp-bolts.com/ 653-479 was the one I had my eye on for this application.
If the helicoil will work that is great. I wouldn't have guessed that it would. Make sure you get the longer length type helicoil rather than the more common shorty-You want all the thread engagement that the long one gives. The stud length shouldn't be as critical-there is enough room up top for a little longer length-I'd go at least 1" longer than the bolt if you drill down-1/2" if you go the helicoil- I'd stay with a stud even if using the helicoil-easier on things than running the bolt in and torquing-I'd also use locktight when installing the helicoil-
