99 Head Job Advice Needed

[Burcham]

Hey all,

Just took my 99 sls with 190k miles in today to have head job done. One garage is dropping cradle, and another is doing head job (new waterpump mandatory). I am planning to have starter, and alternator rebuilt, and may replace ac compressor (its starting to rattle a little). Also planning to get case resealed. What other stuff should I replace while its down (besides obvious worn out lines, hoses, and parts). Without the additional work above, estimates are in the 2K to 2200. Still a lot cheaper than almost any decent used car, but I can't afford to replace every thing on it, and everything on it has 190k miles on it. I have been thinking about the TCC solonoid, but all these parts, and gaskets are starting to add up, while my bank account isn't. Any thoughts about above extra work (what is really important and what can wait) and suggestions and advice for the whole job will be greatly appreciated.

Thanks

Dave

[KHE]

When the case is resealed, make sure the shop follows the directions in the GM bulletin to the letter. The use of the GM Engine Sealant is mandatory. There is NO substitute in the aftermarket.

Make sure the shop is using Timeserts and following the procedure to the letter.

Are you receiving the P0741 torque converter code? If so, plan on replacing the seals in the trans. torque converter clutch apply circuit and the torque converter. If you're not receiving the code, I don't think I'd mess with the transmission.

Does the A/C compressor rattle when the clutch is engaged or disengaged? It might me as simple as needing a shot of refrigerant oil or a new clutch bearing.

[Cadillac Jim]

I'll add my perspective to KHE's excellent advice - most "compressor rattles" are the clutch, in my experience. Compressors go when the reed valves go and that happens silently - you are notified through codes about A/C line pressure and such. The dealer won't overhaul or replace just the clutch, but you can get this done easily in machine shops and such, and it's a whole lot cheaper than a compressor.

[Burcham]

Thanks KEH and Jim,

The compressor rattles when AC is on, and it does seem low on freon, I had to add 1 lb last summer, and if I remember right, it rattled before the freon was added, but stopped after. Maybe a leak somewhere? Machinest said he was going to use t-certs, but when I asked him about sealing the case, he said he didn't know it came apart, (has me worried a bit). What should I ask for about the transmission seals, and about the case sealant. I don't know if the place dropping the engine will work on the transmission or not, they basically are electrical specalists, but have a couple of guys that do rebuilds ect. Just won't do northstart head job. NO BODY within 20 miles of here will, not even the GM dealer who used to sell caddys.

[KHE]

An A/C shop should be able to inject 1 oz. of oil into the system. That may be all it needs.

Here is some information on re-sealing the case:

http://www.cadillacforums.com/forums/cadillac-tech-tips/117232-case-halves-reseal-fwd-rtv-sealant.html

Replace the oil manifold plate if the case is resealed. It is a potential leak point.

Here is some information on the TCC seal replacement: http://www.cadillacforums.com/forums/northstar-performance-technical-discussion/149834-information-p0741-p1860-1998-a.html

I don't think I'd tear into the trans. if you're not having a problem.

[Burcham]

Thanks KEH,

After reading the case sealing process, I'd probably have said I did not know the case came apart either. As for the transmission, yeah I got the 741, I thought everyone did, but for as for the procedure to repair it as outlined in the link above, I think I would probably miss seeing that yellow light on the dash. I'll just have to talk to them to see "IF" and "HOW MUCH DID YOU SAY" to turn it off.

Thanks

Dave

[KHE]

Since the trans. will be out of the car, I'd have the torque converter clutch circuit repaired.

[Burcham]

Thanks KEH,

I'll have to check with them to see if they will do it, or I have to take it to a transmission shop. Their quote for labor to drop and re-install the cradle (no parts repair/replace, gaskets ect.) was $500. This is not their first rodeo with N*'s and they pretty well know what they can make the most money on, and what takes up too much mechanic and bay time. But I'm going to ask today, as they have not started the teardown yet, and may not get to it till next week. They may play dumb, and say they don't know anything about it, but I'm sure they do. For my information, what would be a reasonable price for this repair since the trans will already be out?

Thanks

Dave

[KHE]

Typically, a transmission shop will charge $1200.00 to remove the trans and replace the seals, torque converter, and the TCC solenoid. You can deduct the cost of the removal from $1200.00 to get an idea on what the repair should cost if the trans. is out of the car.

[Cadillac Jim]

I would suggest that if you have the transmission apart to replace the seals, torque converter and TCC solenoid, that you also replace the shift solenoids since you will be looking at them and they aren't expensive, relative to getting that far into the transmission and putting it all back together.

As far as the case half is concerned, I would have a patient talk with the mechanic to make sure that we are all communicating properly. It's hard for me to believe that a full-time mechanic for which your car "is not their first rodeo with N*'s" would not be aware of the case-half leak problem, which, if it occurs happens in about the tenth year. I suspect that he does indeed know about it but just calls it something different. My use of the "case-half" terminology comes from my motorcycle mechanic experience and the fact that the Northstar actually splits the crankcase like a motorcycle does. Ask him about the main caps, and the oil manifold that is exposed when you pull the main caps, for example.

I would want my car engine worked on by someone who has done Northstar engine work before, and, preferably, often and recent - or, who was *very* careful, uses a FSM, and is more than half-bright. In any case I would want to see a shop with a clean, dry floor and a clean, orderly set of tools and such around the work area. If I couldn't find that, I would get an exchange rebuild or a reman, depending on my budget and my future plans for using the car (daily driver, summer car, weekend trip car, etc.)

The TimeSert job got a bad name at dealerships some years ago because of come-backs. A look at the kit and instructions, along with some knowledge of how the dealer techs are managed, tells the tale of why. Dealer techs are paid by flat-rate manual time per job, so working faster means more money, so short-cuts are not only common, they are inevitable. The TimeSert process is very time-consuming, and the most critical steps are installing the alignment mask for each hole, then drilling each tap hole a few millimeters at a time and pulling out the drill and cleaning out the hole between bites. I've heard stories that implied a worst-case where a tech hand-holds a drill and does the whole thing in one push - and the hole is not aligned, off-center, clear through the block, or some combination of these - and then the job fails, either by pulling out the insert when the head bolt is pulled down during the torque-and-twist process, or shortly after the customer drives away, off on his way to climbing Pike's Peak or Mount Washington. I've never heard of a TimeSert failing if the work was done according to TimeSert instructions and the block was sound (no powdery stuff when you drill out the block for any of the TimeSerts). Or, you can have a machine shop do the TimeSert job, or you can send it out.

[joeb]

shop 1 will drop subframe assy. subframe/motor/trans. you can pull off heads without killing yourself. now if you want to remove motor from this hulk and reseal case than you need to unbolt it from trans. where is this assy after shop 1 drops it? how is shop 2 going to pull heads? or where exactly? you say "do heads" but you really mean remove heads, clean block, timesert or whatever and put heads back on. should you even think of taking heads apart?

[Cadillac Jim]

... should you even think of taking heads apart?

No.

[Burcham]

Thanks KEH, Jim, and Joeb,

I did have a good talk with everybody concerned in this operation, including a mechanic at the GM dealer where this car was purchased. It went something like this:

Machinest doing Engine work: I asked if he was going to use T-Serts, he said he would if I wanted him to, but would not guarantee the job. He prefers to drill out the holes and use larger bolts. He said he had used the TS's way back in the past, but had a few failures and had to redo the job. Also said he had fixed many dealer's work using TS's. Said it was a good way for them or small garages to do the work because they usually didn't have the machine tools to do it the way he did. He said he had done probably a hundred or more N*'s and didn't like to have to do his work over for free. As far as the case half, he said he was confused a bit when I brought it up, because he had always refered to it as the crank case cover. When I asked him if he was going to use the GM sealant, he said if I wanted him to, but again would not guarantee the job. He said he used something else, he had used the GM sealant in the past but, that the GM stuff when it set was as hard as a rock and very brittle and sometimes leaked right off. He preferred a sealant that he said looked like tar, and stayed pliable. Also said when he put the halfs together using that sealant, and put the bolts in, after it set, you could remove the bolts and it was still very hard to get it back apart, and would probably run just fine with all the bolts out. Bottom line, he does it his way or no 12 mo 12000 mile warranty.

After That Conversation I went to a mechanic at GM who I'm friends with and had the following conversation:

I told him what machinist I was using and what he intended to do. My friend said yeah, he used to fix some of our screw-ups and knows what he's doing. He said as far as the larger bolts, that was the way to go, he said his very first job (because he was new and low man on the totem pole) there, had been tearing down and rebuilding a N* back in 94. Said they used the T-Certs because that was the GM procedure, and mostly it worked fine but sometimes not. Said that was usually the reason when someone brought a car in for head repair, and was told it would take a week, and ended up being two weeks. Said the Service Manager told the customer they had to wait on parts, when it was actually being redone at a machine shop. Asked him about the substitute in the block sealant. He said no problem there either, they use it all the time on various other engines themselves, and used the other sealant because GM said to. Said he used it on some valve covers, and had to go back in, (said they didn't leak) and had the devil of a time getting the covers back off. I asked him why they didn't do the job anymore. He said he was the only one there that had ever tore down an engine at that dealer, and he hadn't done one in about four years, or as he said since GM's reconstruction. That they shipped all that type of in-warranty work off to larger dealers, and didn't even do that for out of warranty work. Said he thought the bean counters must have figured up they made more money on oil changes, and small jobs.

Talked to the owner of the shop dropping the engine:

I asked him if they could do the transmission repair. He said they would look at it after it was off, but couldn't say he would do it or not. Said if it was simple enough without going into the transmission, they probably would, but would rather I had the repair done at a transmission shop. That they were not very knowledgeable on transmissions, and didn't have tools and equipment or inclination to go into one. At least an honest answer I think. There are two very good local transmission shops so I may end up taking it to one of them.

Anyway that what I have found out today from talking to these people. Any thoughts? Suggestions? I'm feel I'm sort of stuck, one other local shop will drop the cradle, but won't do the heads, no other shop or machinist local will do the heads. After talking to the GM friend and the machinist, I think he will do a good job. At least I'm hoping so.

[joeb]

drop subframe assy. pull heads. use these proven new bolts with warranty and button motor back up. dont touch the starter/alt. or anything else. leave trans alone. than sell car.

[KHE]

drop subframe assy. pull heads. use these proven new bolts with warranty and button motor back up. dont touch the starter/alt. or anything else. leave trans alone. than sell car.

Why would he sell the car after doing all that work??? He wouldn't even recover the repair cost.

[BodybyFisher]

Thanks KEH, Jim, and Joeb,

I did have a good talk with everybody concerned in this operation, including a mechanic at the GM dealer where this car was purchased. It went something like this:

Machinest doing Engine work: I asked if he was going to use T-Serts, he said he would if I wanted him to, but would not guarantee the job. He prefers to drill out the holes and use larger bolts. He said he had used the TS's way back in the past, but had a few failures and had to redo the job. Also said he had fixed many dealer's work using TS's. Said it was a good way for them or small garages to do the work because they usually didn't have the machine tools to do it the way he did. He said he had done probably a hundred or more N*'s and didn't like to have to do his work over for free. As far as the case half, he said he was confused a bit when I brought it up, because he had always refered to it as the crank case cover. When I asked him if he was going to use the GM sealant, he said if I wanted him to, but again would not guarantee the job. He said he used something else, he had used the GM sealant in the past but, that the GM stuff when it set was as hard as a rock and very brittle and sometimes leaked right off. He preferred a sealant that he said looked like tar, and stayed pliable. Also said when he put the halfs together using that sealant, and put the bolts in, after it set, you could remove the bolts and it was still very hard to get it back apart, and would probably run just fine with all the bolts out. Bottom line, he does it his way or no 12 mo 12000 mile warranty.

After That Conversation I went to a mechanic at GM who I'm friends with and had the following conversation:

I told him what machinist I was using and what he intended to do. My friend said yeah, he used to fix some of our screw-ups and knows what he's doing. He said as far as the larger bolts, that was the way to go, he said his very first job (because he was new and low man on the totem pole) there, had been tearing down and rebuilding a N* back in 94. Said they used the T-Certs because that was the GM procedure, and mostly it worked fine but sometimes not. Said that was usually the reason when someone brought a car in for head repair, and was told it would take a week, and ended up being two weeks. Said the Service Manager told the customer they had to wait on parts, when it was actually being redone at a machine shop. Asked him about the substitute in the block sealant. He said no problem there either, they use it all the time on various other engines themselves, and used the other sealant because GM said to. Said he used it on some valve covers, and had to go back in, (said they didn't leak) and had the devil of a time getting the covers back off. I asked him why they didn't do the job anymore. He said he was the only one there that had ever tore down an engine at that dealer, and he hadn't done one in about four years, or as he said since GM's reconstruction. That they shipped all that type of in-warranty work off to larger dealers, and didn't even do that for out of warranty work. Said he thought the bean counters must have figured up they made more money on oil changes, and small jobs.

Talked to the owner of the shop dropping the engine:

I asked him if they could do the transmission repair. He said they would look at it after it was off, but couldn't say he would do it or not. Said if it was simple enough without going into the transmission, they probably would, but would rather I had the repair done at a transmission shop. That they were not very knowledgeable on transmissions, and didn't have tools and equipment or inclination to go into one. At least an honest answer I think. There are two very good local transmission shops so I may end up taking it to one of them.

Anyway that what I have found out today from talking to these people. Any thoughts? Suggestions? I'm feel I'm sort of stuck, one other local shop will drop the cradle, but won't do the heads, no other shop or machinist local will do the heads. After talking to the GM friend and the machinist, I think he will do a good job. At least I'm hoping so.

This is the problem with mechanics, they go against normal repair methods. He won't warranty it for 12 months or 12000 miles?, what a JOKE, he could do this job totally wrong and get 12000 miles out of it, we want 100,000 miles, he is only concerned with 12,000, that is the problem with his logic. Have we seen timeserts pull, yes we have, it is important to check the aluminum material and to install them correct, KHE will comment on this, and if you want to know about a NS failing just beyond 12,000 miles BRUCE had his engine repaired without timeserts and it failed.

[KHE]

Machinest doing Engine work: I asked if he was going to use T-Serts, he said he would if I wanted him to, but would not guarantee the job. He prefers to drill out the holes and use larger bolts. He said he had used the TS's way back in the past, but had a few failures and had to redo the job. Also said he had fixed many dealer's work using TS's. Said it was a good way for them or small garages to do the work because they usually didn't have the machine tools to do it the way he did. He said he had done probably a hundred or more N*'s and didn't like to have to do his work over for free. As far as the case half, he said he was confused a bit when I brought it up, because he had always refered to it as the crank case cover. When I asked him if he was going to use the GM sealant, he said if I wanted him to, but again would not guarantee the job. He said he used something else, he had used the GM sealant in the past but, that the GM stuff when it set was as hard as a rock and very brittle and sometimes leaked right off. He preferred a sealant that he said looked like tar, and stayed pliable. Also said when he put the halfs together using that sealant, and put the bolts in, after it set, you could remove the bolts and it was still very hard to get it back apart, and would probably run just fine with all the bolts out. Bottom line, he does it his way or no 12 mo 12000 mile warranty.

After That Conversation I went to a mechanic at GM who I'm friends with and had the following conversation:

I told him what machinist I was using and what he intended to do. My friend said yeah, he used to fix some of our screw-ups and knows what he's doing. He said as far as the larger bolts, that was the way to go, he said his very first job (because he was new and low man on the totem pole) there, had been tearing down and rebuilding a N* back in 94. Said they used the T-Certs because that was the GM procedure, and mostly it worked fine but sometimes not. Said that was usually the reason when someone brought a car in for head repair, and was told it would take a week, and ended up being two weeks. Said the Service Manager told the customer they had to wait on parts, when it was actually being redone at a machine shop. Asked him about the substitute in the block sealant. He said no problem there either, they use it all the time on various other engines themselves, and used the other sealant because GM said to. Said he used it on some valve covers, and had to go back in, (said they didn't leak) and had the devil of a time getting the covers back off. I asked him why they didn't do the job anymore. He said he was the only one there that had ever tore down an engine at that dealer, and he hadn't done one in about four years, or as he said since GM's reconstruction. That they shipped all that type of in-warranty work off to larger dealers, and didn't even do that for out of warranty work. Said he thought the bean counters must have figured up they made more money on oil changes, and small jobs.

Talked to the owner of the shop dropping the engine:

I asked him if they could do the transmission repair. He said they would look at it after it was off, but couldn't say he would do it or not. Said if it was simple enough without going into the transmission, they probably would, but would rather I had the repair done at a transmission shop. That they were not very knowledgeable on transmissions, and didn't have tools and equipment or inclination to go into one. At least an honest answer I think. There are two very good local transmission shops so I may end up taking it to one of them.

Anyway that what I have found out today from talking to these people. Any thoughts? Suggestions? I'm feel I'm sort of stuck, one other local shop will drop the cradle, but won't do the heads, no other shop or machinist local will do the heads. After talking to the GM friend and the machinist, I think he will do a good job. At least I'm hoping so.

Find another shop to do the work....

Larger bolts may work but there is the positional location that can be compromised. The heads are designed with a specific clearance hole to account for variation in position of the threaded holes in the block as well as the basic fastener size (major diameter). This is not something that is made up - it is basic math. If a larger bolt is used, that takes away from the clearance between the head and the fastener. In theory, there could be an issue where the head bolt could interfere with the head which could cause crossthreading.

As far as the sealer is concerned, GM did extensive testing and developed the GM Engine Sealant specifically for this job. There is NO aftermarket substitute for this sealer. It has been tested, it works, period. The guy says, my sealer or I won't guarantee it? What are you going to do when it is out of his warranty and the engine starts leaking oil like a sieve? Bet that he won't do anything for you. I can't believe how people like the mechanic think they know more about the engine than the prople who engineered it, validated it, and built it.... Think about it: If there was a Permatex brand sealant that worked, do you think GM would have developed a specific sealer? And no, the GM sealer is not made by Permatex... Read the service bulletin on the case half sealing procedure - it specifically mentions the GM Engine Sealant and provides the part number. Here is a copy of the bulletin:http://www.cadillacforums.com/forums/cadillac-tech-tips/117232-case-halves-reseal-fwd-rtv-sealant.html

The fact that the mechanic will only guarantee the engine for 12 months/12,000 miles tells me EVERYTHING about their ability to properly repair this engine....

[Texas Jim]

I would be running as fast as I could from these so called "NORTHSTAR MECHANICS"... (and I use the term loosely).

I would find someone who knows what they are doing and that use recommended and approved Cadillac procedures...

it sounds like these guys are more shade tree mechanics when it comes to the Northstar.

They use the other sealant on "OTHER ENGINeS" and it works fine.

"OTHER ENGINeS" are not NorthStar's...

That's only one example of what would make me run... you have given several others in your posts.

[Cadillac Jim]

Thank you, BodybyFisher, KHE, Texas Jim. I didn't know just what to say.

A typical engine or transmission rebuilder will warranty their engines for three years or 30,000 miles, and some of them have longer warranties. The better warranties include labor to remove and replace the engine and ship it back.

I'm especially disturbed by their refusal to use the GM case half sealer, which is a specially formulated single-use RTV for aluminum-to-aluminum or aluminum-to-oil-manifold sealing that meets GM's most demanding requirements. If they want it to come apart easier, that is a BIG RED FLAG because a Northstar should not come apart more often than about every seven to ten years; saying that they want it to be easier to get back apart tells me that come-backs are common.

Bigger head bolts??? Give me a break - TimeSerts use larger threads which give the same holding as a bigger bolt, but provide a steel thread for the head bolt. TimeSerts are factory recommended for repair of aluminum threads by BMW, Ford, GM, Honda, Land Rover, Toyota, VW, and even Harley-Davidson. If you have something else, they have you covered, just go to their web site and find your TimeSert and your installation supplies and instructions. My 1997 FSM has TimeSert parts under GM part numbers for what seems like every threaded hole in the Northstar block. I'm not impressed if someone "knows better." The only exception to this so far is the Northstar Performance stud kit, which has had no failures that I have heard about. Torque-and-twist head bolts are simple to understand but difficult to duplicate; they hold head clamping force within controlled limits over the operating temperature range for the life of the car - but if you change the bolt alloy, free length, bolt diameter, or thread pitch, you are throwing this away and marching into the unknown. I would wager that bigger head bolts won't stretch as well as the originals as the engine expands so that they will be prone to strip out with overheating, like they did in the notorious old all-aluminum Rambler inline six cylinder engines.

[joeb]

car is worth 1k as is. needs headgaskets. fix them for 2k and car is now worth 3k? or sell car for 1k as is? car used to be worth 3k but it requires an expensive repair now. such is life. shop 1 will drop subframe. but not fix motor. shop 2 will fix motor but not drop subframe. the NS uses a big, long headbolt. somehow the mechanic has found a slightly bigger bolt. i wonder where he found it? or what it is made of? i suppose you can go to a building supply house and buy a 9" long 5/8-16 bolt? does he even mention what pitch it is? inch or metric? does not really matter if you are drilling and tapping block. i am curious to see how this story plays out.

[bigtone]

Timeserts, Norms inserts, and studs are the accepted repairs for Northstars. I've used timeserts once, and Norms once in the 2 HG jobs I did. Although I had no problems with the timeserts, I would use the Norms in the future due to the more robust design. I would not let anyone try 'bigger bolts'. Good information in the above posts concerning what else to replace. I would replace the ac compressor as you mentioned, the system must be broken into to drop the cradle anyway. The only ac failures I have had owning 7 devilles 1988 to 2005 were compressor related, injesting themselves and spreading shrapnel thru the system. That being said, it is your decision as to how much to put into your car. I replaced the hg on my son's 2001 Deville last winter, the car has 170k miles on it now, and I do not regret it, but I did all the work myself so the cost was much lower.

[BodybyFisher]

Hi Bigtone, thanks for posting your experience. Just a small note, you do not need to break the AC system apart to drop the carriage, with the radiator pulled, put something up against the ac condenser to protect it (1/4 inch plywood etc), remove the compressor leaving it connected to the AC system and set it in the space vacated by the radiator and leave it with the body when the engine carriage is dropped.

I replaced the AC compressor on my 96, they do eventually go bad

[bigtone]

Hi Bigtone, thanks for posting your experience. Just a small note, you do not need to break the AC system apart to drop the carriage, with the radiator pulled, put something up against the ac condenser to protect it (1/4 inch plywood etc), remove the compressor leaving it connected to the AC system and set it in the space vacated by the radiator and leave it with the body when the engine carriage is dropped.

I replaced the AC compressor on my 96, they do eventually go bad

I'm just going by what other people said. I did both my hg replacements with the engine in the car.

[BodybyFisher]

Oh ok, I was just correcting this statement "the system must be broken into to drop the cradle anyway", I dont think that anyone here has stated that the AC system must be broken into, why create more work, when its not needed.

Wow, doing this job with the engine in place is a very hard job, kudos to you, BUT....how did you use studs with the engine in place?, my impression was THAT was impossible because you are unable to get the rear head on with the studs, was the stud put through the head while it was in place?

[bigtone]

I did not use studs, I used timeserts once and Norm's inserts the second time. I'm sure that there is not nearly enough room to do studs, but there is plenty of room when doing inserts. I had a few shortcuts that I figuired out, and although most people wont agree, I believe my way to be easier. Most of the work is inside the engine, due to the overhead cams and chains.

Years ago when I was researching doing the hg, I saw on the other Caddy forum most of the guys talked about breaking into the ac system.