head stud washers cracking....

Jono FD3 · Post by **Jono FD3** » Mon Feb 06, 2012 4:22 pm

Just a quick one to see if anyone else has sufferd the washers cracking when torquing them up?!! And oddly enough the 3 that broke, cracked at 70NM.

Jono

SimpleSimon · Post by **SimpleSimon** » Mon Feb 06, 2012 6:29 pm

This may be a silly question, are the washers bevelled/directiional?

sidecar · Post by **sidecar** » Mon Feb 06, 2012 6:37 pm

70Nm is only 51 ftlbs, something going wrong here because from memory the standard torque is something like 68 ftlbs for the long bolts. (Not the stretch bolts, I dunno about them!).

BTW Real steel sell washers that are suitable for the Arp studs, I would have thought that they would be OK for the standard bolts.

I take it that you lubed up the washers?

ged · Post by **ged** » Mon Feb 06, 2012 10:46 pm

Sounds like bad heat treatment (too hard).

unstable load · Post by **unstable load** » Tue Feb 07, 2012 12:35 pm

Wot Ged sed!!
Sounds like a duff batch of treatment.

Jono FD3 · Post by **Jono FD3** » Tue Feb 07, 2012 12:37 pm

they were second hand ones mind guys.....
What I did was match them with steel washers and put the steel ones on the outer bolts with the low torque setting and put the rover ones on the 10 main bolts!

Jono

bigaldart · Post by **bigaldart** » Sat Feb 18, 2012 3:24 pm

We used to break head bolt washers on a regular basis, while running! I had the engine set up for high cylinder pressures to boost bottom end and it was lifting the heads slightly, switched to the washers Real Steel sell and the problem went away. Later switched to ARP studs and have had no problems since. Try the Real Steel washers if you don't want to stud it.

Alan

sidecar · Post by **sidecar** » Sat Feb 18, 2012 3:29 pm

Jono FD3 wrote:they were second hand ones mind guys.....
What I did was match them with steel washers and put the steel ones on the outer bolts with the low torque setting and put the rover ones on the 10 main bolts!

Jono

When you say lower figure on the outer bolts I hope you mean something like 20 ftlbs or even better just don't fit the outer bolts at all.

Before anyone kicks off about this being a bad idea, Rover thought that it was a good idea to omit the outer bolts!