: Doing HG 1997 STS: questions!



ternstes
12-30-10, 04:11 PM
I am doing the head gaskets on a friend's 1997 STS and the four nuts/bolts that connect the pipe from the engine to the cat are very rusted. Can I just cut off the nut and discard the old bolts and replace with new ones?

The car apparently has an AC leak (low refrigerant message on DIC) Can I just disconnect the compressor, condensor etc. and plug the lines?

When I disconnected one of the electrical connections from the line that goes from the dryer to the evaporator, the connection was 'wet'. The car had been sitting for about two weeks... Whatever it was did not really smell like anything

Is there any way I can test for a leak or should I wait until the HG is done?

Should I change the evaporator while the engine is out?

We have disconnected/unbolted most things and once the exhaust bolts are free we should be dropping the cradle. I will add to this post if more questions arise, but from reading all the other posts on this forum, everyone else's experiences have come in handy!

jimsbox
01-01-11, 06:02 AM
I just did my 00 Deville and the flange is connected to the converter not with bolts but with studs. I also had to fight the rust, propane safely wielded is your friend! Seriously, I couldn't budge the nuts and heated each, one at a time for about 5 or 6 minutes with a propane torch and they came right off, one I may have had to heat for about 10 minutes. Heat the nut as evenly as possible, don't worry about heating the stud itself. When you put it back together wire brush the threads on the studs, use anti-seize compound and new grade 10.9 (I believe they are M8 1.25 pitch) nuts. If you have pressure in the air conditioning refrigeration circuit the law states you must have the remaining refrigerant recovered by a licensed tech. If the system has no pressure then it has no refrigerant and you should be able to remove whatever pieces you need to. If it was me, I would get whatever pieces out that I plan on changing or servicing now to make access for the rest of the job easier. You said evaporator, that is the heat exchanger in the passenger compartment, are you sure you didn't mean the condenser which is the heat exhanger in front of the radiator?

mhamilton
01-01-11, 10:18 AM
I am doing the head gaskets on a friend's 1997 STS and the four nuts/bolts that connect the pipe from the engine to the cat are very rusted. Can I just cut off the nut and discard the old bolts and replace with new ones?

The car apparently has an AC leak (low refrigerant message on DIC) Can I just disconnect the compressor, condensor etc. and plug the lines?

When I disconnected one of the electrical connections from the line that goes from the dryer to the evaporator, the connection was 'wet'. The car had been sitting for about two weeks... Whatever it was did not really smell like anything

Is there any way I can test for a leak or should I wait until the HG is done?

Should I change the evaporator while the engine is out?

I'm pretty sure my car has bolts on that flange, so if it did have studs originally then mine were replaced with bolts at some point. I don't see a problem with cutting them or burning them off if necessary. Jimsbox had good advice about the grade 10.9 bolts.

Even though the system is low on charge, it would be better to leave it sealed. If you must disconnect it, be sure to plug any open lines and wrap them with plastic and tape to seal them from any moisture or dirt getting in.

As Jim said, the evaporator is in the dash. No need to replace that unless it's leaking. And no need to replace the condenser unless you had a system failure that spread debris through the system.

The wetness in the low pressure cycling switch could very likely be system oil, and that would be the leak you've been having (I had mine leak in the same exact spot). It's a quick fix... just pick up a new cycling switch from GM, unscrew the old one, and put the new one on. Don't have to discharge the system, it has a schrader valve underneath.

Check around the compressor body for signs of oil and dirt, indicating a case seal leak. If so, you're in for a new compressor.

ponyboyt
01-01-11, 11:11 PM
i ended up cutting my exhaust and re-welding it. They did a good job. Then again, i did it because it was easier than changing the manifolds from the donor engine to the originals in my 97, as the dono came from a 95 and nothing (exhaust) bolted up...

ternstes
02-26-11, 03:41 PM
Hi!

I justed wanted to update... I think it has been quite awhile. There have been a lot of diligent Saturdays but we have the engine out and have started tearing it down. Wow! This is a job!

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0477.jpg

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0479.jpg

Exhaust is off!

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0222.jpg

I couldn't have done this without this forum, what a great resource this is. Overall, I 'd say we have about 20-30 hours in this so far, but we have been going very slow since this is our first time with such a large undertaking.

I will take a picture of the inside of the y-pipe if someone could help me with what sections to grind out.

vincentm
02-27-11, 01:41 AM
Id like to re-attempt my HG repair given the fact that i've the complete Gasket set and oil pan Gasket sitting in my bed room closet, along with Jake's stud kit, this time drop the cradle, but looking at the threads in the tech tips section i'm lost. What i think needs to be posted is a sticky thread listing all thee complete steps from a-z so that guys like myself and others can just do this job themselves, it might be a tough write up but i think it'll benefit members and this site alot. Please hear my request guys, the threads posted jump around alot for me, i want to fix my car, but i need my hand held, and such a guide would allow me to do so.

ternstes
02-27-11, 07:19 AM
Vincent,

I know what you mean. I used one of the threads here to aid in my job, but it did not hit everything, just the major items. I could attach the write up I used along with my own suggestions if you think it would help you get started. It is not difficult, but very tedious, especially when you start lifting the body. My method was an inch or so at a time, checking and rechecking to make sure everything was disconnected.

I would say your first step should be to get the ac evacuated because I do not see how people drop the engine with it still connected. I suppose it is just one more thing to maneuver around as the body is lifted but I just wanted it out of the way. Plus, we had an ac leak anyway.

Feel free to ask questions. I know a lot more than i did two months ago.

vincentm
02-27-11, 11:45 AM
Thanks for the response ternstes. What would be ideal is a complete step by step, with pictures, I've everything to do the job, the stud kit, gasket set, oil pan gasket too, engine hoist, jack stands, engine stand, a 300 piece socket set, torque wrench, breaker bar, 3 jaw pulley, fuel line disconnect tools, everything, and it's all just sitting there collecting dust.

ternstes
02-27-11, 12:26 PM
Well, I want to help you as much as I can, but I didn't take many pictures on the removal. I do have another relative with a 98 sls that I could take some pictures of and include with the steps I used.

First thing to do if the car is still drivable is take it somewhere and get the ac evacuated unless you have the equipment to do it yourself. Do you have the factory manuals? They help a lot with bolt locations, exploded views, etc.

Trust me, if I was able to get where I am, you will have no problems you can't solve.

vincentm
02-27-11, 02:09 PM
Ive an AllDIY subscription, and the Chilton, neither of which provide instruction of dropping the cradle, not sure if the FSM does, which is all im needing, once thats done i can take it from there, might need a guide on reinstalling the cradle but i think if i just work backs, ill be fine.

Sent from my MyTouch4G using Tapatalk

maeng9981
02-27-11, 08:37 PM
FSM gives you instructions of dropping the cradle. Look at the "Engine Replacement" section under the Engine / Engine Mechanical - 4.6L section.

zonie77
03-01-11, 12:23 AM
The FSM walks you through it, with diagrams. The write up I did was intended as an addition to the FSM, not to replace it.

Since most of us are not getting paid, just doing it to help each other out, I don't know if someone would take the time and effort to do what you are asking for. You are certainly welcome to do it.

A couple of months ago someone came on and said they were going to do a step by step deal because there was not one. I don't know if they ever did.

vincentm
03-01-11, 03:59 PM
Oh ok, i didn't know the FSM had the instructions to drop the cradle, thanks for the responses and sorry for hi-jacking this thread.

Submariner409
03-01-11, 05:18 PM
The ALLDATA for my car has the cradle removal instructions and diagrams under "engine", right margin, "removal".

vincentm
03-01-11, 05:35 PM
Im thinking mine is under:


Vehicle Engine, Cooling and Exhaust Engine Service and Repair Engine Removal and Installation Powertrain Assembly Replacement (Preferred Method)

Because it states:

"NOTE: The preferred method of removing the engine assembly is through the bottom of the vehicle. If the necessary equipment is not available, use the alternate service removal procedure."


I think i just need to read it more

vincentm
03-04-11, 01:38 PM
One more question i have. How much do you figure the cradle as shown in the picture in this thread, weighs?

tateos
03-04-11, 03:03 PM
Maybe ~1,000 pounds?

ternstes
03-04-11, 03:24 PM
Yeah, I'd say 1000 lbs is a good bet. I can't see moving the cradle out with rolling jacks. We used a forklift and came in at an angle around the cherry picker.

Vincent, I can scan in the engine removal pages from my FSM and post them here or email them to you if you think it will aid you.

I also just purchased a 2000 STS from a guy here at work for $1000. It won't start and was blowing white smoke out the tailpipe, so I am assuming I get to do this job all over again! :banghead:

Maybe I can video or take more pictures this time? It is hard to stop and take pictures when you are on a roll though, and there is so much to undo on these cars.

vincentm
03-04-11, 03:46 PM
I stopped by Bill McCurley GM and they printed me out some removal instructions, turns out they were the same from my AllDIY subscription, if you can scan those in that'd be great, if not don't worry too much about it, i dont want to inconvenience you.

vincentm
03-04-11, 04:04 PM
Maybe ~1,000 pounds?

Would one of these (http://www.harborfreight.com/automotive-motorcycle/lifts-stands/1000-lb-capacity-hydraulic-scissor-table-cart-93116.html) do the job?

ternstes
03-04-11, 07:15 PM
It could. If it is long enough to get under both the front and rear of the subframe it should hold it. You could also rent a pallet jack from a tool rental place. The only problem with them is the height range. Perhaps stacking a wood pallet or two would give you enough height.

ternstes
03-06-11, 07:47 AM
Vincent,

Here is the FSM instructions on removing engine/dropping cradle. I think the attachment is at the bottom of the post after the pictures.

And, I removed the heads yesterday.

Front (left) head bolts all made a nice 'crack' coming out and all bolts looked clean, no pulled threads.
http://i1185.photobucket.com/albums/z347/timernstes/aaf69c0e.png

Rear (right) head bolts, well some bolts came out very easy. Two bolts had a few aluminum threads pull out with them, but not much. Bolts around cylinders 1 and 3 had a lot of crap on them.

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0501.jpg

rear deck face. cylinder one was 'wet'

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0503.jpg

coolant in the valley

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0508.jpg

here is the rear gasket

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0505.jpg

close-up of cylinder 1

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0506.jpg

Now, what should I clean all the surfaces with? What product works the best?

Submariner409
03-06-11, 10:41 AM
Clean gasket surfaces - use a specific solvent product from parts stores - gasket cleaner/remover. Rags, careful scraping. Do NOT, under any circumstances, get within 100 miles of the engine with a ScotchBrite pad. That one mistake will cost you the entire engine.

vincentm
03-06-11, 10:15 PM
Thanks for the instructions ternstes i appreciate it. turns out i had the exact same steps in my alldatadiy subscription lol. I swear, i'm blonde

zonie77
03-06-11, 11:45 PM
Yeah, I'd say 1000 lbs is a good bet. I can't see moving the cradle out with rolling jacks. We used a forklift and came in at an angle around the cherry picker.

We used 2 floor jacks, one front and one back but it was not a great way to move the cradle.



Maybe I can video or take more pictures this time? It is hard to stop and take pictures when you are on a roll though, and there is so much to undo on these cars.

True, it is hard to stop and take pictures all the time, if someone is there to take pics you start asking them for help all the time!

I know why the magazine guys watch someone else doing the work.

tateos
03-07-11, 02:24 PM
I think I used 3 floor jacks - worked great for me

ternstes
03-13-11, 11:05 AM
Well, we got the engine out yesterday and onto a stand. Wow, is it going to be fun mating the trans to the engine again! We suspected the rear main seal to be leaking and I'd say we were correct. So now the question is which seal and which installer to use. The FSM says to use J-38817 to install a new seal, but there is another updated tool J-42842. Is the updated tool used for updated seals?

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0483.jpg

ternstes
04-20-11, 06:40 AM
After what seems like forever, all the studs are in place!

I am waiting on a rear main seal from GM which is part # 1647308

Is this part # the latest and greatest seal design for the 97 northstar?

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0524.jpg

ternstes
04-25-11, 11:40 AM
Got the engine mated back to the transmission this weekend! It was much easier than I had anticipated. Hopefully only a few more Saturdays!

http://i1185.photobucket.com/albums/z347/timernstes/IMG_0531.jpg

tateos
04-25-11, 03:24 PM
Which seal did you install and what tool did you use to install the seal? I payed nearly $300 to get the correct tool and used it for 30 seconds for the updated 2 piece "cassette" style rear main seal.

http://mechdb.com/index.php/GM_Northstar_crankshaft_rear_main_seal_installatio n

(I didn't use the sealant tool or sealant, as I did not disassemble the lower half - just the oil pan. Also, I re-used the flywheel bolts, and applied a little RTV to the threads)

ternstes
04-25-11, 04:35 PM
I used the updated seal with the updated install tool, J-45390a or something. GM parts direct wanted to sell me the original lip seal after I cross-referenced the part number. I found the tool for $69 on eBay, luckily. The seal pressed on quite easily. I put a dab of sealant at the case halves and that's it. The flywheel bolts were reused with some red RTV on the threads. (I copied your procedure :) ) I did not have an angle gauge so I marked them with a grease pen and turned them to the next point on the bolt (60 degrees).

It also appears that the converter to flywheel bolts had some sealer on them as well, but I can't see in the manual on anyone else's posts that sealer is needed for these bolts. Maybe I am just seeing things?

tateos
04-25-11, 06:12 PM
Maybe there was some thread locker on those threads? I don't remember seeing anything like that, but by the time I did my HG project, the car was on it's 3rd engine and second transaxle, so you can't go by my experience!

ternstes
05-13-11, 08:05 AM
Well, we almost have the engine back in the car! The cradle is just slightly off from the body mounting points... we just could not get it lined up with the forklift. It is back on jackstands, but we will need to raise the body slightly again to get the cradle in the right position. Talk about difficult! I saw another thread here where someone fabbed a rail system to slide the cradle in and out. I think I will try that method on my 2000 STS.

http://i1185.photobucket.com/albums/z347/timernstes/caddy_reinstall.jpg

tateos
05-13-11, 02:35 PM
I had the cradle on 2, or maybe it was 3, floor jacks with wheels - no problem at all lining it up. My body was hanging on the engine hoist cherry picker, so it would swing/rock any direction I wanted. I suggest you attach the steering column to the rack stub before the cradle is 100% attached to the body - otherwise, it can be difficult to lift that boot and line things up.

ternstes
05-13-11, 08:05 PM
I agree! I am taking a much needed vacation to FL for a week, but floor jacks should do the trick. I was attempting to connect the steering shaft before I left and was having difficulty getting it to slide back on. I remember it slid off quite easily so hopefully with the cradle aligned properly it will work.

Thanks for all the tips, tateos!

89falcon
05-14-11, 10:55 PM
I agree! I am taking a much needed vacation to FL for a week, but floor jacks should do the trick. I was attempting to connect the steering shaft before I left and was having difficulty getting it to slide back on. I remember it slid off quite easily so hopefully with the cradle aligned properly it will work.

Thanks for all the tips, tateos!

Just got done with an engine swap on my 97 STS......I did it in my garage....never again...I'm mil, so I'll be on base using the lift next time...

I Disconnected the subframe on the drivers side at the ball joint, CV, and tie rod end....then slit it out the passenger wheel well.....didn't have to jack the car up as far....to move the subframe around, I put it on 2 of these...
http://www.harborfreight.com/material-handling/dollies/1000-lb-capacity-polypropylene-movers-dolly-93614.html

Worked pretty good...I cracked one of them, but it allowed me to move the drivetrain around fairly easily (just push!)

Getting the steering to line up can be a royal #@$%^ IF the wheels moved at all...the steering wheel is probably locked, but the rack and pinon isn't....I had to have my son turn the wheel slightly while I was trying to get the alignment right.......that was one of my biggest frustrations until I tried it that way, and it was easy then....and that isn't the first time I've dropped the subframe (I had to replace a tranny scavenge pump and pump shaft once....):bonkers:

maeng9981
05-15-11, 02:28 AM
I spent a day to get the intermediate shaft back on. It would just refuse to slide on. You need to get it perfectly aligned to slide it and it takes some practice. Also of course it is in somewhere barely accessible.....

ternstes
05-30-11, 07:35 PM
Another update guys. The car is alive again! The cradle lined up perfectly with just a gentle nudge from a set of jacks. Steering shaft was a pain, but I finally found the magical point where it aligned.

Once I connected everything up, the battery turned out to be bad (I guess sitting for 8 months will do that). The first couple of cranking sessions were... Scary. It takes a while for fuel to come back to the injectors! On the initial start, there was a horrible noise coming from the engine area, but then I remembered I had the cap on the power steering pump, which needed a good air bleed.

All we need is to put the tires back on and take it for a spin!

vincentm
05-31-11, 10:28 AM
Awesome!

ternstes
06-01-11, 09:03 AM
Thanks, Vincent! We drove the car for a bit last night. It did not overheat and my friend said it felt more 'powerful' than before the repair. One thing I forgot to do was plug in the coolant level sensor at the bottom of the surge tank... oops. But I am just glad to see no check engine lights, low oil pressure lights, etc! Now I begin my next head gasket project on the 2000 STS I bought for myself!

vincentm
06-01-11, 11:00 AM
When you resealed the bottom crankcase, did you inspect the bearings?

ternstes
06-01-11, 01:12 PM
We did not go that far in. The halfcase seal was not leaking so we left the bottom end alone.