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Drilling and Tapping The Northstar V8......my personal experience so far.

17K views 66 replies 14 participants last post by  98eldo32v 
#1 · (Edited)
I was going to post this in Eldorado_Red's thread "97 ETC Headgasket Project" but I decided if someone just wanted to reference just this part, I should make a separate thread.

This is just my opinion and experience so far and nothing more. I'm not being bias or taking side, these are just my personal conclusions.

Once you have decided to remove the engine by whichever method of your liking, you'll eventually come to the crossroad of drilling and tapping the block for repair. Eldorado_Red's and my personal choice is for studs.

I suppose the inserts have to be drilled also, so some of this may apply but since I've been drilling for the studs I'm a bit more familiar in that area that the inserts.

Things you WILL need:

Cutting Fluid......Motor oil or Trans Fluid. I used trans fluid.

Drill with side handle...Mandatory 1/2" variable speed reversible

Drill Bits...... High strength for cutting metal. 1/2 and 17/32.


I have Northstar Performance's Stud kit with it's first design stud plate. The second design "X" plate looks a lot more user friendly, but that could be just "eye" appeal.

Eldorado_Red chose Carroll Custom Cadillac studs. CCC's items came out a bit cheaper for Red, but was missing drills bits, thread locker and the tap. I suppose those items can be sourced rather easily, but I happen to be a one stop shopper so my kit came with those items.


Eldorado_Red and I started to compare the head studs.

I happen to have the "shiny chrome" version of the Northstar Performance head studs. When comparing the studs, (no matter who's version), there is no comparison to the oem head bolt. One thing I did note on CCC's stud was the allen head key dimple on top of each stud to help speed up installation.

The tap needed seems to be the same for either kit, but CCC's kit calls for a bottom tap at one point in the info on the website, but states it my not be necessary in one of the videos.

The tap needed will be 5/8-11 high strength steel. The starter tap has a taper to it to align itself into the hole. The bottom tap, lacks the taper and cuts immediately.

More on that when we cross that bridge.....

DRILLING........

Here's where the fun began......

My personal opinion..........

Tape off the block with DUCT TAPE. The duct tape is more durable, and "forgivable" heaven forbid you start drilling and the drill "jumps" on you. You want to protect the deck surface of the block from any potential harm.

Take the duct tape and cover the deck surface of the block including the holes to be drilled out. Once the deck is completely covered with the duct tape, smooth the duct tape on the deck to make sure the tape sticks to the deck. (Pre cleaning the deck surface before taping is a good idea if not done so already).

Find the head bolt holes with your fingers by running them across the duct tape. The head bolt holes will leave dimples in the duct tape. You will use a single edge razor blade or x-acto knife and cut the dimples out in a circular motion by sticking the edge of the blade into the lip of the hole and trimming away the duct tape. You may need a small flatblade screwdriver to assist in removal of the dimple of tape from the head bolt hole. Do this to all the head bolt holes to be drilled out. Once the holes are exposed you are ready for drilling.

I was a bit skeptical if the holes could be drilled without a guide plate, at this point I can say yes. Yet, the reason for that, I happen to have a bit more experience with these sort of things, but if one were to feel uncomfortable I would advise using some sort of guideplate.

Even with my experience, you still had to get a "feel" on how to drill these holes out.

1. Load the drill with the 1/2 drill bit. Make sure it's TIGHT.
2. DIP the drill bit into the trans fluid/motor oil. You may want to pour a little in the hole to be drilled out.
3. Align the bit with the hole to be drilled and brace yourself firmly. (you'll understand after a few tries). Start the drill just slightly above the hole, don't have the drill going too slow or too fast. You want the bit to "fall" into the hole but cut smoothly at the same time. IF the bit GRABS (it will until you get the feel of it) hit the reverse button to back the bit out. Re oil the bit and hit forward with just enough speed to enter the hole and cut through without "grabbing" on the aluminum block.

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To be continued......
 
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#32 ·
The left head is in place on the block!!

I cleaned the deck surface with lacquer thinner, then the head. I installed the dowels pins. ( The CCC dowel pins need improvement, they'll get the job done but low quality) I then slid the headgasket down onto the block.

The real fun was the head.

Holding the head at the at the front (facing the timing cover) and the rear (facing the transmission), I positioned the head over the studs and checked for their ease into the holes.

The head started to ease it's way down then stopped almost at the bottom. Ironically, I had to give it a few good shoves to make it the rest of the way then it stopped on the dowel pins.

I figured a block of wood and a few strategic taps will would seat the head, I was wrong. I had to get the nuts and washers out and altenate a tightening sequence to seat the heat to the block.

It's flush, but not torqued into place yet.


So far..... so good.....
 
#33 ·
I figured a block of wood and a few strategic taps will would seat the head, I was wrong. I had to get the nuts and washers out and altenate a tightening sequence to seat the heat to the block.
I don't like that description - ^^^ - not one bit. The head should slide down to the block like smooth velvet, seating flat with no strain anywhere.

Before you set the cams, redo your torque sequence at the last (highest) torque value.
 
#36 · (Edited)
Gentleman,

Unless we're drilling with presicion machines and fixtures, there is going to be some room for error. How much depends on the accurracy if the individual involved and their skill level pertaining to these things.

For one, you can never compare the wimpy head bolt to the stud.

The hole drilled for the stud is at least two times larger than the bolt. The thread pitch is what eliminates the pulling out of the aluminum due to the coarse pitch of the stud versus the fine pitch of the bolt. Due to the fact that the "clamping" force is now induced from the nut and washer on the stud versus the bolt alone in the aluminum, rentention of the head should be superior.

There was no beating of the head over anything. I don't like those dowel pins. They'll work and obviously has worked on many cars that CCC has repaired, but personally the construction/ material leaves much to be desired.

If the studs need to be tweaked in any direction, as stated by Northstarperformance and CCC in their instructions the heads ISN'T going to slide on exactly "velvety" smooth. That is because of the human error angle. Therefore if a particular stud has been tweaked then it has the possibility of slowing the sliding of the head into it's final position.

What has to be used in this situation is caution and common sense. You can't just hammer one side down and then move to the other. You have to gently move the head into position as a "unit". Think of it as putting a lid on a coffee can. You have to go around the lid until it is seated on the can.

If you have to use the nuts and washers to alternately get the head into position, so be it. Gently position head onto the deck.

You re still dealing with solid fixtures per se'. The block is a solid fixture, the head is a solid fixture, the stud is a solid fixture. Out of those three, which is going to be the most flexible if needing a tweak to position itself?
 
#41 · (Edited)
I have the northstar kit with the first design square plate.

I'd like to updgrade that plate to the "x" plate. I hear the bolts are different on the "x" plate versus the first gen plate.

I haven't used my kit yet, but I am going to on my eldo rebuild that I'm going to jump on after I install this motor back into the car.

I'd like to swap the first gen plate for the second gen "x" if possible.
 
#48 · (Edited)
Gates 3-rib tensioner pulleys in RockAuto, $23. Your car, engine, "belt drive".

Pictures in my albums. Been there, done that (pulley only).

If you even remotely suspect that pulley does not turn like greased velvet, change it. Same with the accessory belt drive idler and tensioner pulleys.

EDIT: Instant gratification = NAPA
 
#49 · (Edited by Moderator)
The water pump tensioner pulley looks new, but it felt "notchy" when rotated by hand.

I wasn't too pleased with that. I didn't come this far to have something like that possibly cause a catastrophe. It'll be changed or the whole tensioner is coming out.

Thanks for the Rock Auto suggestion Sub......will check it out.

I edited my post ............. Sub
 
#51 · (Edited)
Well,

I installed the intake cams back onto the heads. The left side went on like butter. The right side due to the cam profile is trying to open the valves on cylinder number 5.

If I rotate the cam, it's attempting to open another set of valves. When I installed the left side, the cam profile never got on the "nose" in any postion for it to open the valves, so I just took my time and re-installed the caps back in their corresponding positions.

The right however will need some ingenious installation techniques that I used to take it off.

I removed the AC Delco plugs that someone must have put on with an impact gun...... They looked damn near brand new.

Now I'm getting ready to reinstall the chains and tensioners......
 
#52 ·
It's the exhaust cam, isn't it? Just install it slightly off the right angle mark to the head surface and then when you get ready to put the sprockets and chains on, rotate the cam slightly to line it up to its proper position. Also, if you are lucky, the cam will "stick" in that position and you won't have to hold it with a wrench while you put the chains on. A helper to hold the cam in position would be nice...
 
#54 ·
Did you remove all the sprockets for all four cams? It is a bit challenging to get the chains on if the sprockets are on the cams already. Maybe it's the intake cam that needs slight adjustment on bank 1, it has been a while. In any event, just use a wrench on the cam to hold it at the right angle position while you install the sprockets and chain. Temporarily zip ties can help hold the chain to the sprockets while you get them in position. Any more pics you can share?
 
#55 ·
Well,

The cams, chains , tensioners and guides are all back in.

I wasted more time trying to figure out how to get the right side/ rear guide back in than setting the timing. The timing was a breeze.

I guess my experience with quad 4's made this a walk in the park.

I unfortunately had to remove the right side intake cam again to install the guide but once in, it was smooth sailing.

Rotated the motor manaully a few turns to make sure everything was kosher........

We're on the way......
 
#57 ·
Yes Vincent,

Changing the main filter and servicing the unit.

I believe Eldorado_Red stated the vehicle ran fine before he parked it for the headgasket issue.

When I remove the side cover we'll see what's going on in there and the state of the fluid.

All the motor mounts are getting changed also.
 
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