: OVERHEATING (Long)



TurboRay
05-20-13, 03:58 PM
Hi guys & gals - Altho I'm an ASE-certified "Master Mechanic", I'm a total newb to Northstar engines. A family friend has a '98 Deville (193K) that's overheating. Oddly enough, it's not manifested by popping hoses, steaming outta the tailpipe or boiling over.......BUT, only by the temp readout on the dash, which has sometimes displayed 239 in normal driving. And, YES, the coolant DOES exhibit the pungent h/gask odor to a small extent.

I recently replaced a leaking w/pump and also installed a new t/stat (preventative). I haven't done a "block check" and hate throwing parts at a prob to find the cure - but, in spite of that credo, I DID install a new radiator......only because my friend used some (yech) Bars Leak recently, and I thought it might have restricted the rad tubes.

Soooooo..............here I am contemplating the dreaded h/gask replacement and - naturally - I have all the newb questions that y'all have probably answered millions of times:

1. What's easier/quicker overall........in-car or OUT?
2. If "out", should I pull the motor from the top or drop the whole eng/trans/cradle outta the bottom (I have a Rotary 9K car hoist and a "table").
3. How can I determine whether the block threads are stripped/weak........should I try to retorque the existing bolts prior to disassembly?
4. Do the heads typically crack or require resuracing (I'll check 'em w/straightedge, but just wondering).
5. Who makes the best gasket kit? Bolts? I was thinking of getting the Victor-Reinz set.
6. Since I doubt I'll be doing a whollotta these, I was thinking of renting - rather than buying - a Time-Sert (sp?) kit online, if nec. ($80 rental + $3 each inserts).
7. Finally (whew)......what, if any, special tool(s) will I need? I've seen pics of all sorts of 'em, including a t/c "holder" (looks like a spreader or sorts) and a set of 4 "hooks" with blocks on the other end.

Have I forgotten anything? Timing-chain/guide/tensioner wear?

TIA - Ray

basscatt
05-20-13, 05:08 PM
FIRST - check the PURGE LINE -

the PURGE LINE is the only way of expelling air from the Northstar cooling system -

it is a 3/8 diameter hose that goes from a hollow bolt in the thermostat/waterpump housing area of the engine - and plugs onto a nipple on the side of the SERGE TANK -

with the engine running - there should be a gentle - constant flow of coolant - from the engine - to the serge tank -

if there is no flow - the most likely cause is a blockage in the hollow bolt -

follow the hose towards the engine - with the engine OFF - remove the hose - use a straightened metal coat hanger - or something similar - and poke it into the hollow bolt -

the coat hanger should go in about 2 1/2 inches -

once the hollow bolt is cleared - you can briefly start the engine to verify coolant flow - be sure to use some sort of container to catch the coolant so you don't make a mess -

check the hose and serge tank for blockage

------------------

next - do a BLOCK TEST -
that is the definitive test for failed head gaskets
in a Northstar motor -
NOTE - that ANY CHANGE OF COLOR -
even the slightest change to a lighter blue -
is a positive reaction -

a 98 with 200K miles - unless everything else on the car is PERFECT -
trans / body / interior / suspension / tires/brakes - etc -
is hardly worth the time/effort to repair -

YOUR out of pocket expenses are going to be MINIMUM of $500 -
not to mention the 20+ book hours of labor -
that will probably take you 30+ actual hours your first time -

RippyPartsDept
05-20-13, 05:31 PM
after heeding basscat's advice

1) OUT
2) either way works just as good as the other ... take into consideration your tools/facility and then take a long hard look at how you would do it either way and then you decide (you're the one who's going to have to do it)
3) DO THE BLOCK TEST ... if the block test fails you need to either stud or insert (big serts or norms serts) the block
4) no - almost always you can just place the heads aside and then put them back on (doesn't hurt to check to make sure though)
5) GM's gasket kits come with the bolts ... those who go with studs usually get aftermarket gaskets so they don't end up paying for the bolts that they're no going to use
6) not sure if there's a question here ... sounds like a good idea to rent a kit if you can find one
7) can't really help you out on this one

if you search around and hunt into the northstar performance sub-forum you will find quite a few of these jobs detailed in pictures and text with lots of discussion surrounding the various stages and steps of the build

i'm pretty sure you will find those more enlightening and informative than any answer we can give to the generic "have i forgotten anything?" because the short answer is "yes" and the long answer couldn't come close the being as helpful as those threads i just mentioned

stoveguyy
05-20-13, 06:24 PM
Are you a pro? Have a shop? Or have a nice home shop you can tie up for 1 week to do this? Since shop rate is 20+ hrs, are you doing this for a fee or favor?

RippyPartsDept
05-20-13, 08:44 PM
By the way, just in case ... The FSM is invaluable ... If you study that and discuss your plans here you should be able to make easy work of this job.

TurboRay
05-20-13, 09:14 PM
THANX for the replies, fellas!

Hmmm......"purge line", eh? I'll check that first thing tonight when she drops off the car. In that same line of thinking, she DID say that it didn't have the overheating issue until after the leaking w/pump was replaced.......even WHILE it was leaking!

Chris - The TimeSert kits are available as rentals (LINK (http://vwparts.aircooled.net/Time-Sert-Tool-Cadillac-Northstar-J-42385-500-p/time-sert-rental-northstar.htm)). But, after further reading, I think I may opt for the CCC stud kit ($330) and buy a gasket kit without bolts. I don't wanna have to do this repair again (heaven help me if I find porous bolt holes or non-shiny "chips" when I drill......sigh).

Sooo......for those who've done this - you didn't need any kinda special tools to hold the t/chain(s)? What about a preference for taking the engine outta the top or the bottom? No favorite/best gasket kits (FelPro, Victor-Reinze, Cometic) or type or gasket (MLS vs. graphite vs. ????)

Stoveguyy - I'm a retired "pro", working out of my home garage with all the tools normally associated with a commercial shop, including a nice twin-post hoist. But, I don't have a need for daily shop access to "drive-in" customers, so I can leave the rack tied up for awhile. I fully agree that a h/gask replacement on one of these motors will be a challenge - especially since it's my first.......but, I'm pretty clever about figuring out the easiest/most-efficient repair procedures.

Thanx, Ray

Ranger
05-20-13, 10:34 PM
Ray, a clogged purge line WILL cause an overheat. If you get no flow at the surge tank end at idle, pull the other end and clear the clog at the hollow bolt where the line attaches to the WP housing aka crossover manifold. (pictured below)

Check the Tech Tips forum. There are several lengthy thread by others who have already been where you are going.

P.S.
If you are considering inserts, consider Norm's NS300L inserts. http://huhnsolutions.com/

Manic Mechanic
05-21-13, 12:36 AM
Hi guys & gals - Altho I'm an ASE-certified "Master Mechanic", I'm a total newb to Northstar engines. A family friend has a '98 Deville (193K) that's overheating. Oddly enough, it's not manifested by popping hoses, steaming outta the tailpipe or boiling over.......BUT, only by the temp readout on the dash, which has sometimes displayed 239 in normal driving. And, YES, the coolant DOES exhibit the pungent h/gask odor to a small extent.

I recently replaced a leaking w/pump and also installed a new t/stat (preventative). I haven't done a "block check" and hate throwing parts at a prob to find the cure - but, in spite of that credo, I DID install a new radiator......only because my friend used some (yech) Bars Leak recently, and I thought it might have restricted the rad tubes.

Soooooo..............here I am contemplating the dreaded h/gask replacement and - naturally - I have all the newb questions that y'all have probably answered millions of times:

1. What's easier/quicker overall........in-car or OUT?
2. If "out", should I pull the motor from the top or drop the whole eng/trans/cradle outta the bottom (I have a Rotary 9K car hoist and a "table").
3. How can I determine whether the block threads are stripped/weak........should I try to retorque the existing bolts prior to disassembly?
4. Do the heads typically crack or require resuracing (I'll check 'em w/straightedge, but just wondering).
5. Who makes the best gasket kit? Bolts? I was thinking of getting the Victor-Reinz set.
6. Since I doubt I'll be doing a whollotta these, I was thinking of renting - rather than buying - a Time-Sert (sp?) kit online, if nec. ($80 rental + $3 each inserts).
7. Finally (whew)......what, if any, special tool(s) will I need? I've seen pics of all sorts of 'em, including a t/c "holder" (looks like a spreader or sorts) and a set of 4 "hooks" with blocks on the other end.

Have I forgotten anything? Timing-chain/guide/tensioner wear?

TIA - Ray

Welcome Ray, I'm also a ASE Master Tech who in the last year or so was thrust into intimate knowledge of the Northstar system by necessity of ownership and the desire to actually use the car for at least another 80K+. Like California, Northstar's a brand new game. I'll give you my tips and lessons learned.

1. Quickest way to replace head gaskets = in car. Quickest way to overhaul the engine is the only way, out. If you're going to do timing chains or reseal the bottom end plan on taking it out. If it's just a fix it quick just pull the heads in the car.

2. Since you have a lift, hoist, and table most definitely drop the powertrain, or rather lift the body off of it. That's what I did. Like you I'm good and finding the easiest or quickest way to do these things, even though it usually takes longer the first time due to mistakes and unknowns. The brake system has rear line disconnects just aft of the sub-frame, then cap. I pulled the master cylinder off the booster and it lays on the engine still sealed. ABS is mounted to sub-frame so that stays. Remove hoses from front lines and cap. Fuel and emissions disconnect as does the steering shaft. All hoses come off, the heater pipes stay on firewall. A/C compressor stays with engine so evacuate Freon first, remove and cap hoses that stay on body. Disassemble fuse box so that you lay harness attached section on engine and harness goes down with it. Pull both axles and disconnect outer tie-rods from spindles. disconnect lower control arms from sub-frame and leave everything else hanging from body, brakes, spindles, and struts will stay intact, ball joints allow it to swivel away. ABS sensor wires stay with engine. Pull the radiator and fans. Misc stuff like air box, brakets, O2 sensors, obviously comes out of the way first, (I stash everything in trunks for safe keeping). Unbolt the exhaust at the front of the system (rear manifold flanges) it will clear fine. I removed the flex-plate bolts from the old school starthr pocket but pulling the intake and starter underneath I think will give easier access. Then you sit the frame on your table and take the mount bolts out. Then it raises away to leave a drive-train now easily accessed and separated. I'm sure I forgot something, just ask.

3. You see any stripped holes when you take the bolts out, don't bother re-torqueing as that's pointless. Mine only had one. Once a hole has failed it has to be repaired, the bolts are tiny and the metal is soft. The CCC stud kit is what I used, they are much larger with longer deeper threads, and no block is so porous that they can't hold.

4. No they don't normally crack, one would have the really try to melt that engine to get that far. I resurfaced mine because after replacing 32 valve seals with a hand spring compressor the surface had many blems. Once again this metal is soft, all finished surfaces must be handled with kid gloves.

5. I prefer Fel-Pro, all theirs are the latest design. Everything in the FP kit's were excellent. I don't know about Victor for the N*, I've used their stuff before on other jobs. If you open the bottom end you'll need the special GM gray silicone and a new separator plate to put it all back together without leaks or problems.

6 & 7. I can arrange to rent you the tools for studding and overhaul as I don't specialize in N*'s. I believe I have all of them. I've quite the investment in them so a refundable deposit would be required. Several important things like the rear main seal and locking the crank can't be done well without them. The hooks and blocks timing chain tools are for the last generation N*. There are three different sets or methods of timing chain tooling. I bought everything (a master set) then ended up only needing bailing wire for mine. This is were factory level information to read ahead of time helps.

I'm sure you've forgot a bunch of stuff and don't even know how much you don't know yet, I know that I didn't LOL. There's another forum on this site that if you go to the forum main page and sort down to the engine specific group you'll find. It's Northstar Performance and Tech. That's were you should transfer this post too and take up residence for the next several weeks. There you'll also find countless documented DIY'ers trips into this task and you can start your own Q&A thread that won't get bumped off page every day and myself and several of the other N* gear-heads on site will follow along and offer all kinds of help and information as you go. Give it a look.

Regards,
Vernon

basscatt
05-21-13, 01:50 AM
THANX for the replies, fellas!

Hmmm......"purge line", eh? I'll check that first thing tonight when she drops off the car. In that same line of thinking, she DID say that it didn't have the overheating issue until after the leaking w/pump was replaced.......even WHILE it was leaking!

Chris - The TimeSert kits are available as rentals (LINK (http://vwparts.aircooled.net/Time-Sert-Tool-Cadillac-Northstar-J-42385-500-p/time-sert-rental-northstar.htm)). But, after further reading, I think I may opt for the CCC stud kit ($330) and buy a gasket kit without bolts. I don't wanna have to do this repair again (heaven help me if I find porous bolt holes or non-shiny "chips" when I drill......sigh).

Sooo......for those who've done this - you didn't need any kinda special tools to hold the t/chain(s)? What about a preference for taking the engine outta the top or the bottom? No favorite/best gasket kits (FelPro, Victor-Reinze, Cometic) or type or gasket (MLS vs. graphite vs. ????)

Stoveguyy - I'm a retired "pro", working out of my home garage with all the tools normally associated with a commercial shop, including a nice twin-post hoist. But, I don't have a need for daily shop access to "drive-in" customers, so I can leave the rack tied up for awhile. I fully agree that a h/gask replacement on one of these motors will be a challenge - especially since it's my first.......but, I'm pretty clever about figuring out the easiest/most-efficient repair procedures.

Thanx, Ray
-------------------------------
Sooo......for those who've done this -
you didn't need any kinda special tools

I'm pretty clever about figuring out the easiest/most-efficient repair procedures.

get the Factory Service Manual - AND FOLLOW IT TO THE LETTER -
or a subscription to AllData BEFORE you turn the first bolt -

there are very few "clever short cuts" that actually pay off -

there are several posts in the "Northstar Performance" forum -
from members that recently did the repairs -
http://www.cadillacforums.com/forums/northstar-performance-technical-discussion/

TurboRay
05-21-13, 02:32 AM
WOW........THANX for taking the time to type up that very-complete "How-To", Vernon! :thumbsup: I'm gonna print it out and use it as a step-by-step guide (I also have Alldata and Mitchell-On-Demand at my disposal, for all the timing marks and torque specs). I like the idea of leaving the struts and LCA's hangin' in the fenderwells - plus, the spindles will probably "clear" the outboard ends of the axles once the LCA bushings are disconnected from the subframe. Soooooo.............out the bottom it'll come. I don't need to remove the flex-plate/t-conv bolts do I (since I don't plan on separating the engine & trans)?

I'll let y'all know how the repair turns out, along with an helpful hints I come across (altho it's not likely that I'll discover anything new that youse guys haven't already experienced hundreds of times, lol).

BTW, Basscatt & Ranger - the purge line/hose turned out to be open and operating properly. It woulda been nice if that had been the prob, but............oh well!! :noidea: Based on the apparently-systematic head gasket &/or stripped/decayed head-bolt holes I've been reading about on this site for the past few days, I'm thinkin' this gal has been very lucky, indeed, to have gone 193K without any prior probs. But, the car is a cream puff (new tires + perfect body and interior) and she loves it......so, in spite of all the potential caveats that I've told her about, she wants to go ahead with the repair

THANX, Ray

RippyPartsDept
05-21-13, 02:48 AM
I should guess that norms serts or the big serts would probably be a good way for you to go especially if you have a hook up for discount/wholesale priced oem parts. Also there's a water pump cover upgrade much discussed here that might be worth lookin into.

TurboRay
05-21-13, 07:18 PM
Well.......I now have some new info from my friend, the owner of the car. She called this morning to tell me that she suddenly recalled that the car had "a head job" - as she put it - done once before. "Just GREAT", I thought! I asked if she had her receipt for the work and she said, "Yes, I dug it outta my car records and have it here" - so, I had her read the list of parts that were used and - sure enough - about halfway thru, she read, "Time-Serts".

Soooooo...........now I'm wondering what kinda can-o-worms I'm about to open up!! Can the larger inserts ("Big-Serts" or "Norm's") or the studs still be used? I'm scared!! I guess the only way to know for sure is to get this POS apart and have a look-see (I got a late start today, due to illness). :noidea:

C'ya - RAY

MoistCabbage
05-21-13, 07:23 PM
As long as it was the original, smaller Time Serts that were used, then yes, larger inserts or studs can still be used.

Submariner409
05-21-13, 08:30 PM
No sense posting two identical threads on the same problem in two different forums - the jumping around accomplishes nothing. This thread is not specifically germane to Deville - so here it sits in Northstar.

Thanks for the consideration ....................

All posts on the problem are now here. Go back and do some homework.

Manic Mechanic
05-21-13, 08:33 PM
Sub's good at cleaning things up around here. :yup: Northstar's never go as smoothly as you think, be prepared for more surprises Ray.

Vernon

RippyPartsDept
05-21-13, 08:43 PM
As a side note I think jake told me that his kit can be used even after a big sert job if they fail (which I've never seen - and we've been doing big sert jobs for a long time.)

Ranger
05-21-13, 10:12 PM
Well.......I now have some new info from my friend, the owner of the car. She called this morning to tell me that she suddenly recalled that the car had "a head job" - as she put it - done once before. "Just GREAT", I thought! I asked if she had her receipt for the work and she said, "Yes, I dug it outta my car records and have it here" - so, I had her read the list of parts that were used and - sure enough - about halfway thru, she read, "Time-Serts".

Soooooo...........now I'm wondering what kinda can-o-worms I'm about to open up!! Can the larger inserts ("Big-Serts" or "Norm's") or the studs still be used? I'm scared!! I guess the only way to know for sure is to get this POS apart and have a look-see (I got a late start today, due to illness). :noidea:

C'ya - RAY
One thing to keep in mind is that IF this was a warranty job, GM will only authorize Timeserting holes with pulled threads as opposed to all 20 (the proper way). So it's entirely possible that it may only have one or two bolt holes Timeserted. The other possibility is that they either did not hold or should never have been done in the first place (see the "Root Cause" Sticky in the Northstar forum).

TurboRay
05-21-13, 10:26 PM
No sense posting two identical threads on the same problem in two different forums - the jumping around accomplishes nothing. This thread is not specifically germane to Deville - so here it sits in Northstar.

I agree completely - but, of course, I had no way of moving it myself, lol! THANX for consolidating everything........and SORRY for posting in the wrong section. :noidea:

Ranger - The previous job was apparently done by an independent shop - not as a warranty repair by GM - so, short of calling my friend back to see how many inserts were used, I won't know until I get it apart.

Anyway, I'll be back at it tomorrow morning (very little got done today, due to illness) and - hopefully - have the heads off by the afternoon and able to see how the block holes look! :thumbsup:

C'ya - RAY

RippyPartsDept
05-21-13, 11:43 PM
We always inserted all holes. No point in only doing the stripped holes no matter what warranty guidelines say.

Ranger
05-22-13, 11:46 AM
Makes sense, but who pays?

RippyPartsDept
05-22-13, 11:54 AM
I can't really recall exactly (it's been so long since we've don't a warranty HG repair)
but we would probably have found all 20 holes to have need for drilling/tapping/inserting and GM would have no problem paying for the full job
i doubt they ever asked for any blocks back as cores for the sole purpose of catching a dealer inserting 20 holes when they should have only done 4