Northstar Engines and System Technical Discussion Discussion, On the road again! in Cadillac Engine Technical Discussion; It’s been six years (2007) since I purchased this 1994 Cadillac Deville Concourse N* with HG issues from a local ...
It’s been six years (2007) since I purchased this 1994 Cadillac Deville Concourse N* with HG issues from a local salvage yard for $600.00. It ran enough to get it titled and plates hung on it, then it took up refuge in the back of my shop pending head gaskets.
This year it finally happened.
I actually started collecting tools and equipment for the project in the fall of 2012, Hoist, engine stand etc. I removed the N* out the top with no problems. I approached the engine bay from the right side with the hoist and lifted the engine up and over the right fender. Once out and mounted to the stand I proceeded to de-grease and pressure wash the engine.
The disassembly of the top end reveled the loss of threads in two of the head bolt bores and a burnt gasket at cylinder #8, (front left corner next to the water pump).
I have been following a lot of the N* HG discussions on the forum and decided to use “STUDS” instead of “BOLTS” in the repair. I chose “CCC” in TX to supply the 20-machined studs required, mainly because of the cost, ($350.00) and the rapid delivery to my door, (3 days).
I obtained a top end gasket set from “O’Reilly’s”, ($200.00) and a machinist friend provided drill bits and tap. No power drill was used; I chucked the drill bit in a tap wrench and bored all the holes by hand. Boy did that pay off when the heads slid on effortlessly.
I did experience a sheared guide pin requiring some extra effort. Also when tapping one of the holes, (the end hole at cylinder #7 near the starter valley) a casting void opened up about halfway down and toward the bell housing. I pressure tested the hole and found it to be tight so I used “JB WELD” on the end of a Popsicle stick to fill the void. I then cleaned the threads up with the tap after letting the repair cure for 24 hours. After putting everything back together, careful to torque everything properly to spec’s I attached a tilter/chains and hung it on the hoist.
The engine installed easily and with out any real trouble. The task of reattaching the harnesses went smooth as well. The only issue being; I missed disconnecting the small wires to the speed sensor at time of engine removal resulting in breakage, a simple repair. Also the “knock Sensor” got damaged while installing the engine, another simple sensor replacement. I filled the block/radiator, power steering pump and crankcase. I was surprised at how much oil it took to hit the dipstick!
I did have to buy a new battery before I could get the gas door open. It was on fumes when I parked it 6 yrs ago. I dumped 5 gal of good gas in it and cranked it over until it popped a couple of times then I turned the key off. My next attempt was just quick turns of the key and after about 4 or 5 tries it fired up. I let it run a little to pump the fluids then shut it down to check levels. I then started it again, this time it fired right away and ran smoother. I did take a little while for the lifters to quite down through, and then it just purred. Very surprised No codes displayed either?
Actually this has been the easiest engine r&r I’ve ever done! Could'nt have done it without this forum!!!!
Oh Ya! 2,000 miles now and not a drop of any of the fluids consumed or on the ground.
I say, "If ya got a hot N* that needs fixing, and you know which end of the wrench to use. Go for it". Happy Motoring...
Drill bit by hand cranking? Wow. I see a 1810 woodworker drilling holes for oak dowel pins in my mind? U did not use a jig plate with guide bushings? I suppose ur machinist pal said it would be ok and it seemed to work for you.
That’s right! No guide plate.
Brace and Bit? LOL! I like that.
Hand drilling the soft aluminum was very easy to control. The tap wrench T-handle I used gave me all the leverage I needed to do the job. To keep check of perpendicular alignment I used an aluminum carpenters speed square.
Yes, my machinist friend did recommended doing it that way, since there was no way to really chuck up the engine block with a drill press in order to have the control needed, and my variable speed power hand-drill, even with a jig, would just have too much grab & pull for my liking. Also, in my book, taking a cheater bar to correct stud bolt alignment problems is best avoided.
My Papy always said, “The proof is in the pudding”, and In my case, there were no issues installing the gaskets and heads.
BTW, The engine pull procedures I used was published in my FSM for the 1996 model year under engine removal as “Alternative method”.