STUDS ARE NOT THE WAY TO GO!

[KHE]

My reasoning for asking about the equivalant torque was curiosity, i know torque angle is more accurate method as it eliminates drag or the presence of lube on the threads that can cause variance and inaccuracy in desired torque.

By the way, regarding studs vs bolts, I said my thinking was flawed because....I was thinking with studs, when torqueing was performed, the pull on the aluminum threads would be a straight pull with studs as the you torque a nut at the top, vs a galling twist using the bolts, but, that thinking is flawed because the timesert inserts effectively acts as a stud against the aluminum threads and its the same, the insert pulls up on the aluminum threads as it is torqued, the bolt twists against the insert's threads NOT the aluminum block threads so there is no possibility of galling and thereby weakening the blocks threads, duh. I hope that makes sense. Galling while torqueing the bolts I felt would damage the aluminum threads, here is an interesting description of galling, note this statement "For example, aluminum is a metal which will gall very easily"

https://en.wikipedia.org/wiki/Galling

Kevin why do I need the rear main bearing seal installer?, I didnt plan on splitting the case half unless I saw evidence of leaking. Is that something I need to get into? I plan to change the torque converter seal, axle shaft seals and maybe the oil pan seal.

The threads on the headbolts have a microencapsulated threadlocking compound that acts like an anti-sieze compound.

If you're not splitting the case, then you won't need the seal installer - for some reason, I thought you were resealing the case.

[BodybyFisher]

I have hijacked this thread, I am sorry, it was an accident but,

While the engine is out should I do a case half seal? I hate getting into the main bearings, do they need replacing at that point to maintain "crush". My nature is to make jobs bigger, because I am there...replace it..

[KHE]

The case half will only seep - it will not leak to the ground. The oil manifold plate WILL leak oil to the ground if it is not sealing. I would inspect the engine - if it isn't leaking, I'd leave it alone.

The main bearings wouldn't need to be replaced but if you have the pistons and rods out, the rod bearings will need to be replaced along with the connecting rod bolts. The rod bearings are a one time use only since they crush slightly on assembly. Re-using rod bearings will result in a spun bearing on short order.

All that said, if you're just re-sealing the case, you wouldn't need to replace the main bearings.

If you do wind up sealing the case, familiarize yourself with the torque sequence and values thoroughly and have all your sockets you will nead within reach. The GM engine sealant only has a 20 minute work window and you need to work quickly.

[BodybyFisher]

Thanks Kevin

[Cadillac Jim]

If the block has already been Timeserted, and the head bolts came out with no Timeserts on them, you probably don't have to do *anything* except clean the holes and use new head bolts, with the twist-and-turn specs for the new head bolts.

KHE, Logan - how do you tell if the block has already been Timeserted?

[KHE]

KHE, Logan - how do you tell if the block has already been Timeserted?

Use one of those inspection mirrors with a magnet at the handle end - the Timeserts are steel. Also, you should be able to see them using an LED inspection light - I have one that is small enough to fit down the bolt hole but the magnet is the best bet.

[BodybyFisher]

Its obvious that a block is timeserted. The heads are not off yet, so I don't know, but I doubt it was timeserted. This engine sat for three years without running it was owned by an elderly woman, the battery was charged and it started immediately and ran quietly

One of the reasons I want to timesert it IS because it sat for three years and because it was owned by an elderly person who probably did not maintain the engine. Say the coolant was 4 years old then it sat for three years and it was green coolant....I don't want to worry at all.

[BodybyFisher]

If the block has already been Timeserted, and the head bolts came out with no Timeserts on them, you probably don't have to do *anything* except clean the holes and use new head bolts, with the twist-and-turn specs for the new head bolts.

KHE, Logan - how do you tell if the block has already been Timeserted?

Jim I realize you think I am an azzhole but please try to hide it.

Do you really think I wouldn't know if a block was timeserted? Really Jim? Calling in Kevin and Logan? And then you instruct me like a child? I would appreciate it if you would stay off my threads. I stayed away because of you, dont make it hard for me to return. I hope that was gentlemanly enough for you, as you noted above.

[Cadillac Jim]

If the block has already been Timeserted, and the head bolts came out with no Timeserts on them, you probably don't have to do *anything* except clean the holes and use new head bolts, with the twist-and-turn specs for the new head bolts.

KHE, Logan - how do you tell if the block has already been Timeserted?

Jim I realize you think I am an azzhole but please try to hide it.

Do you really think I wouldn't know if a block was timeserted? Really Jim? Calling in Kevin and Logan? And then you instruct me like a child? I would appreciate it if you would stay off my threads. I stayed away because of you, dont make it hard for me to return. I hope that was gentlemanly enough for you, as you noted above.

BBF - Please forgive the misunderstanding. I am very sorry if I came across that way. I have no idea what you are working on or why but threw in my 2 cents about checking for existing Timeserts because at this late date a lot of them have been Timeserted, because any responsible mechanic, like yourself, will not put heads back on a Northstar without Timserts (or inserts or studs of their choice). I only mentioned it because it hadn't come up in the thread, which is public and will turn up when people search it, probably thousands of times, and I thought that the mention and KHE's point about checking with a magnet was excellent and ended the issue.

As far as four years of green coolant, *then* sitting for three years, I think you will see coolant seeping around the head gasket when you pull the heads. It may be OK for a period of time but you are right in not trusting such a history to the point of being willing to do a Timesert job before you see the problem manifest. I certainly would do what you are doing.

[BodybyFisher]

I am here because I need the wonderful resources of the board and the members expertise in these matters. The purchase of the 97 Eldorado ended up being a can of worms to where fixing the engine would have been shortsighted. In actuality, the tensioner debris ended up in every part of the engine and it did significant damage and posed a serious future threat. The ONLY option was to tear the engine apart and inspect every component for damage. Every lifter in the front head was bad, tally up, 32 lifters x $20 each. The engine needed to be replaced. While it is 2 years later I am still angry that the problem was minimized and framed to be a simple valve problem, it is NOT in my rear view mirror and I have not forgotten how much this has upset me. The lifter that was bad NEVER rotated, the bore was seriously scored and out of spec at .005. Many bores were scored and many either never rotated or stopped rotating and had grooves cut into them. But that is a moot point because the debris from the tensioner ultimately rendered the engine useless until it was disassembled and inspected carefully. The filings acted as an abrasive and damaged the tops of the lifters. Once I saw the damaged tensioner I knew fixing the engine was not an option.

[barczy01]

Very common for lifter wear on these older 99-93 engines. Lack of oil changes and the lack of zddp in todays oil. I tell people on these older engines to go on ebay and buy concentrated bottles of ZDDP and add a bottle ever other oil change.

Being in business for myself for over 5 years and working on these cars for over 20 years, if TIMESERTS didn't work, I would have failed long ago.

[BodybyFisher]

Very common for lifter wear on these older 99-93 engines. Lack of oil changes and the lack of zddp in todays oil. I tell people on these older engines to go on ebay and buy concentrated bottles of ZDDP and add a bottle ever other oil change.

Being in business for myself for over 5 years and working on these cars for over 20 years, if TIMESERTS didn't work, I would have failed long ago.

IMG_0970.JPG

Ill post photos but the wear occurred as the lifters were not rotating unlike the one you have in your hand they had about 40K miles on them. Oil was changed religiously. In addition drbris from a failed tensioner was beat into the top of a few lifters. I do plan to add zddp along with an oil that has the highest zddp content.

Let me ask a question, when you see that type of wear are you concerned about the cam lobe and do you use the cam? I miked the cam lobes and didnt measure or observe serious wear. What causes the lifters to rotate?, are they suppose to be domed?

[Cadillac Jim]

I am here because I need the wonderful resources of the board and the members expertise in these matters. The purchase of the 97 Eldorado ended up being a can of worms to where fixing the engine would have been shortsighted. In actuality, the tensioner debris ended up in every part of the engine and it did significant damage and posed a serious future threat. The ONLY option was to tear the engine apart and inspect every component for damage. Every lifter in the front head was bad, tally up, 32 lifters x $20 each. The engine needed to be replaced. While it is 2 years later I am still angry that the problem was minimized and framed to be a simple valve problem, it is NOT in my rear view mirror and I have not forgotten how much this has upset me. The lifter that was bad NEVER rotated, the bore was seriously scored and out of spec at .005. Many bores were scored and many either never rotated or stopped rotating and had grooves cut into them. But that is a moot point because the debris from the tensioner ultimately rendered the engine useless until it was disassembled and inspected carefully. The filings acted as an abrasive and damaged the tops of the lifters. Once I saw the damaged tensioner I knew fixing the engine was not an option.

You paid $500 for the car. A reputable head rebuilder told you to buy three lifters and drive it. You have a complaint after two and a half years???

[Bruce Nunnally]

Let's stay on topic please. I suggest you each put the other on ignore, which will hide any content, contact, etc.

http://caddyinfo.ipbhost.com/index.php?app=core&module=usercp&tab=core&area=ignoredusers

If I can figure out how I'll do that for you.

[barczy01]

Easy you two :/ . The lifter in the picture above came out of a car with low miles 85k, 4 years ago and the oil was clean along with the engine. I believe the customer told me it was his moms car and it was driven in the city, short trips and went to the dealer for oil changes. So dealer oil changes in late 90's-2000 was using bulk oil for an oil change. I have seen lifters much worse than above and the insides of those engines were filthy black oil.

I inspect cam lobes on cases like this and they look fine.

Ofcourse the lifter will get to the point where it won't rotate but that's to the point where the cam dug a trough into the lifter.

[BodybyFisher]

I am here because I need the wonderful resources of the board and the members expertise in these matters. The purchase of the 97 Eldorado ended up being a can of worms to where fixing the engine would have been shortsighted. In actuality, the tensioner debris ended up in every part of the engine and it did significant damage and posed a serious future threat. The ONLY option was to tear the engine apart and inspect every component for damage. Every lifter in the front head was bad, tally up, 32 lifters x $20 each. The engine needed to be replaced. While it is 2 years later I am still angry that the problem was minimized and framed to be a simple valve problem, it is NOT in my rear view mirror and I have not forgotten how much this has upset me. The lifter that was bad NEVER rotated, the bore was seriously scored and out of spec at .005. Many bores were scored and many either never rotated or stopped rotating and had grooves cut into them. But that is a moot point because the debris from the tensioner ultimately rendered the engine useless until it was disassembled and inspected carefully. The filings acted as an abrasive and damaged the tops of the lifters. Once I saw the damaged tensioner I knew fixing the engine was not an option.

You paid $500 for the car. A reputable head rebuilder told you to buy three lifters and drive it. You have a complaint after two and a half years???

$500 wrong Jim, your memory is wrong ask Bruce

Reputable yes, knowledgeable on the Northstar no, they didnt even check lifter bore clearances and blamed an injector. I found the problems they did not NOR DID THEY MAKE THAT STATEMENT about replacing 4 lifters. I was extremely disappointed with their analysis, I brought it back twice, they did not even have a bore gauge. I personally don't care what they said, they did not find a cause for the misfire, the valve, seat and guide were fine. That lifter bore was toast, they did not focus on it, and I think they minimized it realizing that they should NOT have rebuilt the head, it was NOT a candidate for a rebuild with this damage and excessive clearance, the bore needed to be bored out and sleeved, but try to find someone to do that!, and the cost is ridiculous to do that. Photos taken with Nikon D90, 50mm Macro lens at F8 on a tripod with flood lights.

Serious scoring, and a clearance of .005 spec is .001 to .003. This could have caused 1) oil leakage around the lifter and the lifter collapsed at idle when the oil pressure went low, as we know at idle the NS oil pressure drops to single digits in come cases, 2) the lifter could have binded or bound in the bore SLOWING its RETURN to closed position, which based on your leakdown test sounds plausible. Above idle RPM the valve train inertia could have overcome the binding and the valve closed but at idle RPM it could have been slow to return. I have a link that shows that a BURR in the bore can do that!, this is WAY MORE than a BURR. This photo does not show it but there is wear at the top showing it was tilting or cocking under cam lobe pressure. The debris in this bore from the tensioner is the obvious reason for the lifter not turning, look at that scoring.

Butterfly pattern on top of lifter in that bore above, it never rotated see machining marks, a close look at that wear mark/line shows it just broke through the hardening. This lifter is at the end of the lifter oil galley and debris would naturally get to the end. More scoring damage is obvious in #8 and #6 than in #4 and #2.

Edge of lifter shows it was binding

Better view of butterfly wear, never rotated, look at the uneven wear pattern toward the edge at the top how close it was to the edge compared to the bottom, it shows the clearance was excessive and the lifter tilted in the bore.

And lets not forget that this debris is also probably IN the lifters. An inspection of the oil pump showed minor scoring but the tolerances are so tight that debris would just be pushed through.

If I reinstalled that head I would have had the SAME misfire and soon the back head would have had the same problem.

Come on Jim, you raved about Jaspers CLEAN ROOM, an aluminum tensioner destroyed itself against the timing chain and distributed debris all over the engine, try to be objective this is a serious failure that we NEVER have seen. I researched the heck out of this, this is NOT a common cause of a misfire, but I have some great info that I will show. I have worked on this analysis for 2 years on and off. I did not want to get rid of this car, I love this car.

The car sat for two 1/2 years, needing an engine right from the beginning. You do NOT slap a head back on when debris is strewn around the engine. I almost junked it numerous times, because it needed an engine $1000, installation $1000, cooler lines, engine mounts and possibly a radiator, plus I spent $350 on the head (a waste of money, they should have inspected and spec'd it out it first to determine its viability of a rebuild given the complaint of a misfire in #8, they blamed the injector, in spite of the leak down test) and $50 for a replacement head from the junk yard. The tranny as good as it is has over 200K on it and its not like you had a light foot.

The machine shop builds racing and performance engines, while my tech loved cadillacs, he did not get deep enough into the problem and his boss pushed me away. I went to another machine shop I know for 40 years Elasser engines and he right up front said he is NOT familiar with the Northstar and you need to be very familiar. Lab machine shop basically did a lousy job and just TOOK my money for NOTHING, even though they build standard performance engines.

Jim am not complaining, simply reporting facts, I love this car.

The fact is you took great care of the car, I love the car, its AWESOME. I stayed away BECAUSE, I knew you would get upset, and considered junking it as a result. I expressed my concern to Kevin 2 years ago, that I would never be able to present the facts on this board because you would fight against the facts. Jim, I need to PRESENT my findings, its part of the process, if this were MY car you would be sitting there with pop corn, wait this IS my car, LOL... This is a VERY interesting study if you just sit back and observe, its not your car anymore and you need to keep an open mind, its NOT your fault and you can keep your Jasper stock (a joke). You said this is in your rearview mirror let it go and PLEASE let me present this analysis of what happens when an INTERNAL COMPONENT self destructs. When have we EVER seen something like this?

You need to let me present the facts, I stayed away TOO LONG

[Cadillac Jim]

The car had 162,000 miles on it when it was sold. The Jasper engine went in at 118,000 miles and had 44,000 miles on it and had no signs of any problems, other than a very slight miss at idle that the PCM picked up. I have it on good authority that loose carbon had wrapped around an intake valve. The tranny had been serviced every 30K-40K miles since the car was new and had been flushed and had 100% Dexron VI in it. The main reason that I moved on is because I wanted the CTS-V, and I still miss the Eldorado. The car blog is here under Jims 97 ETC for those interested in the facts.

As a general rule, I talk here only about Cadillacs or related topics, and I believe that this is a good policy for a gentleman's forum.

[Bruce Nunnally]

I suggest you each put the other on ignore, which will hide any content, contact, etc. See info here: http://caddyinfo.ipb...ea=ignoredusers

[BodybyFisher]

I suggest you each put the other on ignore, which will hide any content, contact, etc. See info here: http://caddyinfo.ipb...ea=ignoredusers

Bruce, I think it will be fine. I do not harbor any ill feelings toward Jim other than his defensiveness toward this issue. There is NO reason to defend against facts, hell he is driving a CTS-V, took great care of this car, with my help I might add, and he and I love this car. It is what it is, an internal component damaged the engine and it CAN NOT be ignored, the debris must get out of the engine and to do that it must be taken apart. I will prove how bad this is when I pull the engine and inspect the rear head and post photos of the tensioner. Its not Jims fault he treated this car like a baby, its beautiful and rare.

[Cadillac Jim]

I see that Bruce already set the "ignore" flag for me. Excellent. Now, back to Cadillacs...

The most common aluminum thread repair approach is helicoil, which may be fine for a ground cable connection but is folly for anything torqued over 15 lb-ft IMHO. I've heard of the end of a helicoil in a spark plug hole causing detonation and destroying an engine, so I wouldn't use one for a spark plug, although I have also heard of lots of successful spark plug helicoils in motorcycles, outboard motors and such.

There are several Cadillac Northstar head bolt insert possibilities out there. As I mentioned in a post in the old thread, I found an insert for Northstar head bolts that came in a bubble pack, no kit, no centering plates, no warranty. I really hope that that stuff is off the market by now.

Viable solutions for Northstar head bolts include Northstar Performance studs, Norm's Inserts, and Timeserts. You may know of others. I have no way to evaluate Northstar Performance studs or Norm's Inserts other than there don't seem to be come-backs from them. My feeling is that you don't see come-backs from Timeserts either, but several years ago dealer techs did have problems with them. If you've ever worked in a by-the-job flat-rate-manual-charged shop, you know that a good tech will beat flat rate times, and some techs will take short cuts. The Timesert process is slow and methodical, as drilling and threading aluminum *must* be to avoid weakening the new threads or getting the insert at a slight angle. There is no shortcut for a Timesert job that won't court failure, and dealer techs can make more money on brake jobs and belt changes.

I've never heard of a Timesert job failing for a DIY job for a fellow working on his own car and getting up to speed on the process before starting the job. I'm sure that they are out there because it's a big world but it's clear to me that Timeserts work and provide a permanent repair. I believe that in most cases the heads can be pulled again and re-installed without touching properly installed Timeserts in most cases.

The good thing about studs is that if you are working with an engine a lot, pulling the heads and putting them back is a lot quicker with studs, and the threads are right there where they are easy to clean. The downside is that putting a head over the studs is touchy and you can easily scratch the bottom of the head, and if you do so on a sealing surface, the you must polish out or fill the scratch to prevent a leak. If you are doing it once for a lifetime repair, I don't see an upside for studs.

Another thing about inserts versus studs is getting the right torque-and-twist specs and keeping the clamping force within design limits over the temperature range of the engine. With factory head bolts, GM/Cadillac takes care of that. With studs, *you* must pick the stud alloy, stretching strength, temperature expansion rates, and initial clamping force (torqe-and-twist specs). No come-backs says that Northstar Performance is doing a good job with that. But we've had people come here saying that they have a machine shop and want to do their own studs...

All said and done, I would rent or borrow a Timesert kit and do that if I had one to do, my own or a friends or relatives. If I were in the business, I would rely on the installed base and warranty of Timeserts, and *never* try to rush a job, particularly during the drilling and tapping part of the work. I don't think rushing a Northstar Performance stud job or a Norm's Inserts job would be a good idea, either.

That goes for any Aluminum engine, which these days is all of them except possibly Diesels and some larger truck engines, not just Northstars. Not that I'm likely to take the time and rent the space to do a motor these days, so I'm speaking hypothetically.

If some ham-fisted dude managed to strip out a spark plug on my Suzuki Bandit 1200S, I would pull the head and use inserts in all the plug holes. And I would go to Time Fasteners and ask them which parts to order. But motorcycle heads and barrels were 40% silicon back when I tracked such things a long time ago, and such an alloy approaches cast iron in strength, and I never heard of a plug being stripped in a four-cylinder motorcycle. If that happened with my CTS-V, I won't speculate on the process that would be invoked but the head would have at least one Timesert in its plug holes when all was done.

[BodybyFisher]

"other than a very slight miss at idle that the PCM picked up. I have it on good authority that loose carbon had wrapped around an intake valve"

A very slight miss that wouldn't pass inspection as the check engine light was on.

good authority? Reflect back to the photos, they are hard to deny.

[Cadillac Jim]

... The lifter in the picture above came out of a car with low miles 85k, 4 years ago and the oil was clean along with the engine. I believe the customer told me it was his moms car and it was driven in the city, short trips and went to the dealer for oil changes. So dealer oil changes in late 90's-2000 was using bulk oil for an oil change. I have seen lifters much worse than above and the insides of those engines were filthy black oil.

I inspect cam lobes on cases like this and they look fine.

Ofcourse the lifter will get to the point where it won't rotate but that's to the point where the cam dug a trough into the lifter.

I have used nothing but synthetic since I discovered it for my 1990 Pontiac Grand Am with the Quad 4 HO (6800-7000 RPM red-line; I shifted at 7200 when pushing it). When I traded it in for my 1997 Cadillac ETC, the dealer told me that Mobil 1 was an upgrade fill, and I used 10W-30 Mobil 1 for an oil change or two, I believe. Shortly thereafter they told me that GM recommended 5W-30 for my VIN '9' Northstar year-round (at least in Southern California). That kept the engine sludge-free forever. When it was pulled out at 118,000 for a pulled head bolt (I had gone 7 years on a coolant change ) we pulled the cam covers to use on the Jasper, and the heads, cams, timing chains and sprockets, etc. looked like new.

If you have an old engine and you want to try to clean it out, you might just try an oil change. You can try synthetic if you want higher detergent oil to help solve a sludge or shellac problem. If you must pull it down as it is, of course, you grin and bear it, with lots of parts cleaner and shop rags.

Sometimes I think that garage queens are the toughest cars to maintain. My wife's car is rarely driven and I spend a lot more time with it than with my CTS-V. But that isn't fair because all I ever do with the CTS-V is add washer fluid and have the oil changed, once I discovered my Goodyears. That's why the CTS-V blog is so dull. The Eldorado was pretty much as good. I changed the CTS-V coolant at four years, including the intercooler, to avoid the stale coolant blunder. I also had the transmission serviced at 50,000 miles.