: My Northstar HG project

10-18-08, 10:58 PM
Well after my '99 ETC has been sitting for over a year and I have been saving up money I finally decided not to spend $3000+ for a shop to do the work and got the courage to work on it myself. I myself am mechanically inclined, I have built Chevy small blocks, big blocks, and old VW engines, as well as doing almost any repair on mostly GM cars old and new but the Northstar just seemed too daunting as I am not a professionanl mechanic and dont have great tools. But I dived in anyway.

I have been taking my time I spent 2 hours wednesday and 2 hours friday and almost 6 hours today but I got the whole subframe/engine/trans out. I ran into some problems and got lost a few times, cursed at it constantly, and my hands are all banged up, but I got through it. I will try to post some pictures soon. Now comes the next daunting task of tearing the engine down and repairing the headbolts.

I certainly couldnt have done it with out the help of this forum and also the factory service manual. Thank you everyone who have posted usefull info on the HG repair. I will keep you posted on my progress but it may be slow as I dont have much time to work on it and I also dont even have a kit yet to do the headbolts but hopefully in a months time I can get her done and it will be a nice birthday present for me.

10-18-08, 11:38 PM
best of luck to ya
i did an 01 Deville DTS and its my only HG repair job yet THANK GOD lol

10-19-08, 03:04 AM
^ I see you too are in PA :sneaky: and you can do head gaskets oh joy!!!

10-19-08, 10:35 AM
i did it on a DTS at the shop i work at
when the HG went on my 97 ETC i had the dealer do it lol
much less room to work around in there haha
not to mention they did the job for 2k instead of the normal 4-5k as they had replaced the motor previously for me under warranty

10-19-08, 05:31 PM
Mine N* sat in my garage on the subframe for 2 months before I got up the courage/had the time to actually start tearing into it. It is an extremely daunting task but take your time and be sure to double check everything you do - it would really suck to get it back together and remember that you had forgotten something.

Make sure you cover everything well when you start drilling and tapping, you want to make sure you keep the chips out of the engine, if you can get a helper to hold a vacuum on the drill for you while you drill it wouldn't be a bad idea. If/when you blow the chips out of the holes make sure you hold a rag or something over the hole so the chips don' scatter everywhere.

Use a square to align the cams with the head - do not rely on your eyeballing to get it "good enough".

Borrow/buy a harmonic balancer installation tool - best way to get the balancer back on properly - leave the starter out until after you get the front cover back on and torque the crank bolt (this will allow you to put a bolt through one of the holes in the flex plate to hold the engine while torquing the crank bolt).

When you are putting the water pump drive pulley back on the cam be mindful that you do not put it on too far - you can use a power steering pulley puller/installation tool to take off and put on the pulley, but when you are putting it back on make sure you put a washer on that will not allow the installation tool to go too far - if you do the ribs on the backside of the pulley will get into the head casting and mess it up.

I am sure that if I were to give it more thought I could come up with a bunch more helpful tips but I am out of time for now.

It is a very good feeling when you get it all back together and you light it off for the first time. I have had mine running again since memorial day and to date have had no problems.

Good luck, if you have any questions drop me a line.


10-19-08, 06:25 PM
I've gotta take note on this, it's getting near that time to pull my motor and fix it. Been running hot, and today just used up enough of the new coolant I put in yesterday to turn the check coolant level message on. It was just blowing it out the surge tank cap when it was too hot, but it didn't over heat once since I changed the coolant. Looks like I won't be pulling the engine in the Triumph this winter....and pulling mine out instead..lol. Anyone know how much big engines hoists are goin' for?

10-19-08, 07:11 PM
Thanks for the tips everyone. I took a few pictures of the engine right before I started and after it was out. As for engine hoists I bought one for this project and I got it at Pep Boys on sale for $150 Regular $200 I think it is a 2 1/2 ton rating. You wont find many new ones less than $200. I plan to use it when Im done with the Eldo to rebuild my old Delta 88.




10-19-08, 08:47 PM
i saw a 95 sts on craigslist with the heads in the trunk. the shop gave up cuz the block is stripped and the owners decided to sell it as is. 500 obo! not sure of the cars condition or mileage. needs to be towed. haha. i bet dropping the subframe with only a shortblock in would be easier. hmm.

02-27-09, 01:42 PM
Well it took me a little more than a month (mostly because I am busy with work and school or it was too dang cold to work on her) but I finally got the job done. I had a problem with oil pressure when I first got it started and I still dont know what the problem was but after torquing the heck out of the balance bolt and still no pressure I pulled the oil pump out (wasnt really hard even with the engine in thankfully) and I replaced it with a new one and now I have oil pressure. She still clattered after running for about 20 mins but I let it cool down and restarted and all clattering gone. That was yesterday and today I started it up and drove it around the block and got her warmed up and everything seems fine.

I have to go get it inspected but I do have a new trouble code P0147. It a sensor in the cat conv. I cant figure out how to reset the codes in the car? Does anyone know how to reset the codes in the car?

Anyway we will see how she does when I get her licensed and can really drive her, but I want to thank everyone here who posts useful information on the post. I would have never gained the courage to do this job on my own if it wasnt for this forum. I also would have been a little lost. I do have the FSM but sometimes it doesnt speak in english and I get better help here than the book. Im glad I have the book but Im glad I have the forum too.

#1 thanks to 97eldocoupe aka Jake. I used his stud kit and it worked perfectly and A+ customer support. He is probably tired of me calling him but he doest act like it and he is always willing to help. Great product too I wouldnt use anything else. It is good to know there are still people out there with the knowledge and ingenuity to produce a product like this that the market does not have.

Here are some more pictures and thanks agian. I'll keep you all posted on how the progress continues.

02-27-09, 06:20 PM
Wow man, Nice job!

...Does anyone know how to reset the codes in the car?...

Go into diagnostics mode and wait for it to get to "PCM?"
-Press Fan up to go into the PCM menu
-Press Fan down until you get to "PCM CLEAR CODES?"
-Press Fan up to clear the codes. It should display "PCM CODES CLEAR" and then take you back to the next option in the PCM menu
-You can turn the key off or press the OFF button a bunch of times to exit diagnostics mode.

02-27-09, 07:13 PM
Thanks! I was trying to find that in the FSM but that book seems a little disorganized to me. maybe its just me but I have the FSM for my 91 fleetwood and its a lot eaiser to read.

Anyway Ill try that and see if the code will come back. If it does than I guess I need to replace the o2 sensor. Why would it go bad now when it was working before I took the engine out. Maybe I should check the wires but Im sure I got them back on ok.

02-28-09, 09:51 AM
According to Ewill the manuals went to crap when they started publishing them electronically and the paper version became a secondary product. It seems like they just spit the paper copies out in random order and there's no logical flow. The cross referencing of sections is the worst. The FSM for my 1990 was far better than my 99.

03-01-09, 01:41 PM
are the stud threads in the block timeserted? i have not been following the stud conversion process lately. i do recall yanking out the hollow dowel pins to be able to timesert those holes though. maybe i am forgetting those bad memories.

03-01-09, 06:15 PM
The studs are very recently developed for the Northstar and serve as a repair method without the use of any kind of inserts. Inserts are just bandaids. As you can see in the picture of the stud compared to the original headbold the studs have a much coarser thread that goes into the block. They also put the torque up on top of the head instead of the threads in the block. Seems to me like this is the way they should be built in the first place.

Anyway the studs were developed by our very own 97eldocoupe aka Jake and he has began marketing them with a new website at www.northstarperformance.com
His kit comes with everything you need to drill and tap the threads.

03-01-09, 10:21 PM
the timeserts are obviously larger than the factory bolts and the bigserts are even larger so there must me some meat in the block so the holes can be drilled and tapped for the larger studs.

03-02-09, 01:09 PM
Nice picture of the stud next to to the stock bolt - I don't think I have seen that before.

03-02-09, 05:23 PM
There's plenty of meat in the block for the studs- due to the lower oil drain-back passages there's no room for more- at least I wouldn't trust more- but there's enough material in the block for the studs without compromising strength or sealing area.

PimpDaddy... I never got tired of the calls because this is what I do- I want to hear the progress/issues that people are having. Customer feedback is very important to every business and important to the future of any product's success. I am so glad to hear your Eldo is working good again. Nothing scares a person more than pulling a Northstar for the second time. You are the very first person to purchase the stud kit from me and the first one besides me that installed the studs.

I've had some calls saying that it's time consuming drilling and tapping the block. But the one thing I will not compromise is the accuracy of the drilling/tapping process to make it faster. The tap/drill block is combined and held down with two bolts and needs to be moved for each hole. This takes time, but it's better to take an extra half hour and get the holes straight. Do it once and do it right.

I've got my own special set up for drilling and tapping but the last couple of engines I used the drill/tap block that I sell with the kits and each time, the gaskets slipped right over all 10 head bolts and so did the heads- all the studs were perfectly straight and in-line.

03-02-09, 05:42 PM
I actually did the HGs on a 3.5 liter V6 from a 2000 Oldsmobile Intrigue. These LX5 "ShortStar"engines come in only the Intrigue and the Aurora (the 4.0 was the upgraded engine on the 01-04 Auroras, the 3.5 being the base engine). The same thing needed to be done to this engine block- there is now one 3.5 V6 Intrigue that's studded just like the 90+ Northstars out there. I know it's a topic of pretty much no interest on a Cadillac forum but a stud kit for the 3.5 LX5 V6 will be available soon too.

To be perfectly honest, I'd rather do the HG's on a Caddy any day.

03-02-09, 07:17 PM
Thanks Jake. The drilling was time consuming but I was taking my time too, like you said better do it right than fast. I took it in to get it inspected today and it failed the emissions even with the check engine light off. The guy said that since it hasnt been driven much since I got it back together that 3 of the sensors hadn't finished calibrating and were not reporting? He said it just needs to be driven for 50-100 miles and retested, so I have to go get a temporary plate now.

The 2 miles to the shop and back were fun though. I just don't dare driving it with expired plates, it is my luck I'll get a ticket.

03-02-09, 07:45 PM
I just don't dare driving it with expired plates, it is my luck I'll get a ticket.

Same here.

03-03-09, 09:35 AM
There were some threads with the parameters that set the "good" flags. Several trips that warm up the engine and have some freeway speeds should do it. I don't remember the exact details.