97 Etc N* Head Gasket Project

[97Concours1]

I'm probably the one that keeps questioning the torque values all the time. Since I had the same problem that Tatos did, I just think it is worth some discussion so others might avoid a problem. As far as consulting Cadillac engineering, I think we are on our own when we use the aftermarket Norm's inserts and Rockauto head bolts. These two variables change things enough that Cadillac would probably not have any suggestions except to use original GM parts. The problem here could just be the quality of the Rockauto head bolts. They are much less expensive and probably not as consistant in their strength.

[submariner409]

Get in touch with ARP. If anyone other than CHRFAB knows torque and bolts from different manufacturers, it's them.

[AlBundy]

AJ should know or at least give info on what he does when he changes them out.

[krechtr]

Thanks for the help today Tateos. Got all of the inserts in... it took a lot more time than I though it would but they all ended up pretty straight. I should get the head gaskets and bolts in tomorrow and plan to bolt the heads back on Wednesday. This is what AJ posted on the Fiero thread:

Cylinder Head Bolt (M11)
First Pass .................................................. .....................................30 N·m.........22 lb ft
Second Pass .................................................. .................................+60 degrees
Third Pass .................................................. .....................................+60 degrees
Final Pass .................................................. .............................+60 degrees (180 degrees Total)
Cylinder Head Bolt (M6).............................................. .......................12 N·m.........106 lb in

that is what I am going to use... will let you know how it turns out.

[tateos]

krechtr and I live about 30 minutes apart in the Phoenix area, so I went down and gave him a little help and advice on Sunday.

On my own project, I got the right/rear head on and bolted up this weekend - also bolted up the coolant crossover and replaced the rack and pinion steering gear with a new one (mine was original and pretty worn out and suffered from "morning sickness").

I don't think the Fel-Pro cylinder head bolts I got from Rock Auto are inferior - they are made in US and 29 out of 30 worked just fine - I think I just got one bad one, and that could happen to anyone. By the way, did I ever mention that Rock Auto said they had not heard of these bolts snapping, but they sent me a new set of bolts, no charge and no questions asked - I didn't even have to return the broken bolt or the rest of the set. I think that is pretty good customer service.

[blb]

Originally Posted by STEVEHO

With a really good forum like this, isn't there someone with a direct connection to Cadillac engineering to get a positive answer and explaination for this very important final head bolt torque value?

If Cadillac Engineering knew what they were doing in the first place, there would be no need for this thread, and there wouldn't be a big market for aftermarket inserts for the Northstar.

[Rafterd]

Went to the dealer ship today and they quoted me a price of $2127.75 and I furnish the inserts. I thought that was not bad.

Bill

[Rafterd]

Oh forgot, Please keep this going I am enjoying reading this.

Bill

[97Concours1]

Originally Posted by blb

If Cadillac Engineering knew what they were doing in the first place, there would be no need for this thread, and there wouldn't be a big market for aftermarket inserts for the Northstar.

I'll second that. I've never really understood the reverence shown to GM at times related to this problem (i.e. "you can use Norm's inserts - they're not GM approved".) I'm as loyal as anyone when it comes to GM products, but the ball was dropped somewhere on this one.

[97Concours1]

Delete

[STEVEHO]

Actually I was talking about the torque value discrepancy in the FSM. I was also under the mistaken? impression that Rock Auto sold G.M. parts. Years ago when I was into building up VW engines, the first thing you did was to Helicoil all the block fasteners. So it's not unusual for a high performance light alloy engine to have this kind of problem. I'm very impressed with the engineering that went into this engine but if my head gaskets blew, I would probably be joining you in your displeasure with GM. I wish you all a successful repair job.

[krechtr]

Got the motor back together today... no problems with the inserts. I am ready to put it back in the car tomorrow morning but have haven't installed the harmonic balancer yet. My neighbor told me that it has to be lined up to work correctly but I don't see any marks on the timing chain cover or the balancer to line up with. I am doing this work from AJ's post on the Fiero website but it doesn't mention it. Anyone have info?

[Ranger]

The only thing I can tell you is that the oil pump is driven off of it and it MUST be torqued properly or you will have oil pressure issues. Torque is quite high as I recall.

[krechtr]

I have the torque value... I just don't know if it is suppose to line up with something like the timing gears do... like the groove on the balancer of a SBC is lined up with a timing mark.

[Ranger]

I don't think so, but I would not swear to that. See if Ewill or AJ pipe in. I'll PM them for you.