Are my bolts supposed to break?

[TheKryptKeeper]

So I'm changing my head on my ka24de. I tried to do it with my original head and when putting on my head bolts, 3 of them snapped when I was tightening to 75 ft-lbs. It ends up that that head was incorrectly checked and didn't hold pressure, so I got a new one and while checking my valve clearances, a camshaft bolt broke while going to 17 nm! What the hell? Am I supposed to change all of my bolts when doing the head gasket? Also won't the aluminum head break before the steel bolts?

Krypt

[wagzilla260rs]

ARP that's all you need to know...go buy some

[S13xCrazy]

thats a terrible situation.

Are you sure your torque wrench is accurate? Have you dropped it? Are you using the right conversion? (foot pounds, inch pounds, nM)

[darens13]

you should replace the bolts. they are sort of a one time use sort of thing, because they stretch a little when you torque them.

[sebazztard]

thats a terrible situation.

Are you sure your torque wrench is accurate? Have you dropped it? Are you using the right conversion? (foot pounds, inch pounds, nM)

very very very easy to mix up when not paying attention, we all do it. but this was the very first thing that came to mind (correct lbs). and no your bolts shouldnt break, they were designed for the torque! hope you get everything straightened out, sounds like a nightmare.

[h.240]

The aluminum head shouldn't break before the bolts do. It is a good idea to replace the head bolts since they are designed to stretch under tension, I actually just read that in a Popular Mechanics magazine an hour ago. Here is the tightening procedure for the head bolts as per the FSM if you don't already have it - I would also get your tourque wrench calibrated to make sure you are torquing to the correct specs.

[TheKryptKeeper]

I juat bought a new torque wrench after the head bolts broke. Nissan insists that the bolts do NOT stretch and are to be reused.

[offroadbob]

it was 75 N/m not 75 ft/lbslook at the FSM pic

I was having the same problem when I was tightening down my cam cap bolts. 25 in/lbs or something like that and I kept snapping them at 25 ft/lbs.

[sebazztard]

its a good idea to get new bolts, but you broke way too many to be just an accident. i think it was your torque wrench causing the breakage. personally after all the work i would get new bolts just for some insurance. live and learn right?

[TheKryptKeeper]

The head bolts broke at 75 ft-lb. I just got a new torque wrench. I just checked and I confused in-lbs with ft-lbs. So, that is that. However, I just checked my injectors, and one was 25 ohms and another was 45 ohms. :-( Do I have to replace them or can I fix them?

[e1_griego]

You're not supposed to go past ~60 ft/lb for the head bolts....

Alex

[lrb_2000]

yeah.. I torqued my arp's to like 59ft/lbs.... the FSM says 55-63ft/lbs

you were looking at 75 to 84 nM

[S13xCrazy]

^^ yeah,

I think you made some mistakes haha. you aren't in the right units. These bolts don't just break.

[OutToWinPAHC]

Too much torque and they are torque to yield bolts so they must be replaced after one use.

[nissanman04]

The head bolts broke at 75 ft-lb. I just got a new torque wrench. I just checked and I confused in-lbs with ft-lbs.

Yeah, you might break some bolts if you are using 12x the designed torque.

[TheKryptKeeper]

Hmm.... Well, damn.