Cracked Block - '97 Seville STS

[KHE]

Every 600 miles or so, the low coolant message would come on and I'd add some coolant.  Pressure testing the system revealed several leaks at the hose clamps, etc.  Those were easy to fix but I still kept getting that hot coolant smell and the usage dis not seem to diminish.  A couple of days ago, I pressurized it to 15 psi and let it sit for a couple of hours.  There was coolant coming from the back of the engine but I couldn't see where it originated.  The heater core pipes were OK and not leaking so I added two tubes of Bars Leaks to the system and it appeared to seal - the coolant stench was gone for a couple of days.

My wife drove the car about 130 miles and the message appeared again so she added about 1-1/2 quarts of coolant.  When she returned home, the message came on again.

I have the car in the garage up on ramps.  I pressurized the cooling system to 15 psi and the back of the engine was wet with coolant.  I slid under there on a creeper and found what appears to be a crack towards the bottom of the #1 cylinder water jacket.  I removed the spark plug on #1, brought it up on TDC then pressurized the cylinder to 120 psi while holding the balancer bolt with a breaker bar.  No coolant erupted out of the surge tank but I can see where it may have puked coolant out the overflow at some point since the end of the overflow hose was wet with coolant.

I can smell exhaust gasses in the surge tank with the engine running but there are no bubbles.  I believe the cracked block is allowing a small amount of exhaust into the coolant.

I'm wondering if some high temp RTV would seal it enough co curtail the coolant usage until I can locate another car?

[barczy01]

Engine is toast. sorry.

[BodybyFisher]

What would cause a crack that low?  

Did the engine have a knock?

If a head bolt pulled could movement or hammering cause a crack?

[Bruce Nunnally]

I would think jb weld as a temporary fix until you can do an engine R&R

[KHE]

4 hours ago, barczy01 said:

Engine is toast. sorry.

Yep - I'm just trying to buy some time until I can locate a replacement car.

2 hours ago, BodybyFisher said:

What would cause a crack that low?  

Did the engine have a knock?

If a head bolt pulled could movement or hammering cause a crack?

No clue.  No knock or other unusual noises.  The car still runs very well - it just goes through coolant like it's going out of style.  There must have been internal stresses in the block to make it crack after all these years but it doesn't make much sense to me - it seems like it would have cracked early on after I rebuilt the engine, not several years later.

2 hours ago, Bruce Nunnally said:

I would think jb weld as a temporary fix until you can do an engine R&R

I removed the engine to transmission brace to gain access to the crack and it is worse than I thought.  The crack starts at the base of the #1 cylinder and it is really pronounced at the base of the #3 cylinder.  I cleaned the area and applied some GM Engine Sealant to the area just to minimize the coolant loss.  I thought something flexible would be better than epoxy such as JB Weld. 

I'm not going to replace the engine - the car has 220,000 miles on it and is 20 years old.  I am looking for a '98-'04 Deville as a replacement - hopefully from inland Florida.  I like the pre-2000 Devilles since to me, they are a "miniature Fleetwood Brougham" but the 2000+ Devilles are very nice cars - I really like my 2005 Deville.

[rockfangd]

Very sorry to hear.

I would say anything but replacement is a bandaid at best. You couldnt possibly get a picture could you?

I love my Seville. I see very few of them, especially our body style. I say the Seville is the rarest of the 3 models.

Has the engine been overheated or anything you could think of to have caused the problem.
Wish you were closer. I would love to find a donor for my Seville.

chances are the crack is larger than what you can see and it has probably increased in size over time til it started to leak.

Not sure on your climate but the coolant would not have frozen would it?

[KHE]

26 minutes ago, rockfangd said:

Very sorry to hear.

I would say anything but replacement is a bandaid at best. You couldnt possibly get a picture could you?

I love my Seville. I see very few of them, especially our body style. I say the Seville is the rarest of the 3 models.

Has the engine been overheated or anything you could think of to have caused the problem.
Wish you were closer. I would love to find a donor for my Seville.

chances are the crack is larger than what you can see and it has probably increased in size over time til it started to leak.

Not sure on your climate but the coolant would not have frozen would it?

Thanks.  I just wish this problem would have manifested itself in April I would have had my Fleetwood and my '05 Deville out of winter storage.  The GM engine sealant is a Band-Aid to buy me some time (hopefully) to purchase a different car.

The engine was never overheated and there is no way the coolant would have frozen - it was kept at 50% concentration which is -34° and it has never gotten that cold here.  Maybe -5° (but not in the last year) and the car sits in the garage from November through March and the garage rarely gets below freezing.

The crack was definitely longer than I originally thought - I first saw it at the base of the water jacket of the #1 cylinder but when I removed the brace, I noticed it was larger and went across almost the entire width of the #3 cylinder.

What parts are you looking for?  I may part out the car at some point.

[rockfangd]

I would like a whole one.

I feel you. Both of my caddys are away for the winter. I am driving a nissan. The seville always gets put away early and does not come out of the garage til I know for sure there has been enough rain to wash away the salt.

My Deville sits outside this year though. Better to sit outside than to be driving it in our crappy roads and weather. I dont have a spot for it this year.

I have to pray that nothing will go wrong with either one of them before spring. 

[KHE]

12 minutes ago, rockfangd said:

I would like a whole one.

I feel you. Both of my caddys are away for the winter. I am driving a nissan. The seville always gets put away early and does not come out of the garage til I know for sure there has been enough rain to wash away the salt.

My Deville sits outside this year though. Better to sit outside than to be driving it in our crappy roads and weather. I dont have a spot for it this year.

I have to pray that nothing will go wrong with either one of them before spring. 

 

My Fleetwood Brougham doesn't come out of storage until the rain washes the salt away - some years, it is May before that happens.  My '05 Deville comes out of storage the first part of April and if there is still salt residue on the roads it is only driven on dry days.  I kept the Seville washed - once per week in my garage all through the winters.  I always flushed the underbody and all the brake lines are still like new.  It's a shame to have to scrap the car - I was hoping to get 300,000 miles out of it.

Oh well, it still holds my record as the car with the most miles - 220,000.  My '86 Buick Park Avenue had 210,000 on it when I sold it in 2006 - that was my previous record.

[Bruce Nunnally]

2003 DHS http://dallas.craigslist.org/ftw/cto/5920956190.html in Fort Worth w 112K miles.  Posted as for sale by owner.

$2900 but looks like service stability on, so needs something.

[barczy01]

JB weld won't hold back the water.

 

[OldCadTech]

Bummer, the JB definitely won't work.

Do you know anyone that can heli-arc? Front cyl --- soo may be able to get to it for a weld???

If all else fails....  I have a 2002 Seville STS 74K on the clock that is going up for sale soon.

And a 1998  Seville STS 130K  on the meter, wouldn't take much to make me put it up for adoption either.

[KHE]

22 hours ago, Bruce Nunnally said:

2003 DHS http://dallas.craigslist.org/ftw/cto/5920956190.html in Fort Worth w 112K miles.  Posted as for sale by owner.

$2900 but looks like service stability on, so needs something.

Thanks for the listing Bruce.  This had to happen in the winter when I have my Fleetwood and Deville in storage...

 

2 hours ago, OldCadTech said:

Bummer, the JB definitely won't work.

Do you know anyone that can heli-arc? Front cyl --- soo may be able to get to it for a weld???

If all else fails....  I have a 2002 Seville STS 74K on the clock that is going up for sale soon.

And a 1998  Seville STS 130K  on the meter, wouldn't take much to make me put it up for adoption either.

OldCadTech,

The crack is on the rear bank - the engine would need to come out to weld the water jacket regardless of the location (front or rear bank) as there is no way to completely drain the coolant with the engine in the car.  The heat from the heilarc would just keep drawing out the residual coolant, preventing a good weld.  Besides, there had to be internal stresses in that area of the block for some reason and even if the heiliarc did work, it would crack again in time - not really a gamble I want to take as it is a lot of work to R&R the engine.

There appears to be exhaust gasses in the coolant - the surge tank smells of exhaust but there are not any bubbles in the tank - most likely due to the crack distorting the head sealing surface at the block.  The car doesn't overheat though.  I did loosen the surge tank cap to the first position to keep the pressure down so the car can be driven on short trips in order to buy time.

[OldCadTech]

Sorry Kevin,

I was referring to the front of the engine not the front of the car.

If you are "engineering" a repair, and, IF you have someone that can heli-arc ( AKA Gas Tungsten Arc Welding ( uses helium ) ), use a angle head drill and drill a drain hole below the crack, grind the crack clean, weld the crack and the drain hole shut. I've seen good welders repair aluminum blocks before BUT I admit they WERE out of the vehicle. Maybe access through the wheel well after removing the tire and motor mount and the trans bracket. I don't know where the crack is so I can't say for sure. Ugly any way ya look at it...

If it doesn't work the block is gone anyway.

Only other "fix" that might slow it down is the "liquid glass" treatment which is another PITA to do with below average success rate.

[KHE]

I attempted to repair a cracked Northstar water jacket for someone a few years ago - with the engine out of the car, a weld shop drilled holes at each end of the crack to relieve the stress, then ground out the crack, then heiliarced the crack/filled in the holes.  That repair lasted only about 3-1/2 years and about 45,000 miles before it cracked again.  I suspect the same would hold true for this one if I went through the work to pull the engine and re-install it.

To me, it's not worth repairing at this stage.  The car is 20 years old, still in good condition but the clear coat on the hood is gone and the basecoat is abraded away in spots and that is a $500 repair at a body shop.  That coupled with a used engine and parts to R&R the engine on a 20 year old car with 220,000 miles on it just isn't worth it to me.  I would have liked to put another 100,000 - 150,000 miles on it just to say I did it but it isn't going to happen.

There are a lot of early to mid 2000's Devilles in Florida at are in excellent shape for decent prices.  A 2002 Deville with 67,000 miles on it went for $5750 the other day on ebay - it looked like brand new.

[OldCadTech]

OoO I was under the impression you were looking for a temp repair to get you through the winter months.

I mis-understood, sorry. 

[BodybyFisher]

Kevin, this was in an email from CTSV who repaired BenATX's cracked engine, I hope this helps, Ben was able to drive the car from Houston to Austin but he noted that it still leaks. It was a sizeable crack.   If you search BenATX you will find the thread on his cracked engine if you need it.  Feel free to contact CTSV directly, Mike

"I used a combination of marine grade epoxy putty and forced it into the cracks after sanding and cleaning the block. I had drained the engine of as much coolant as possible but one of the cracks was still leaking water. 

Used the putty first to stop the water, then waited for it to set, cleaned again and mixed up some steel reinforced quick drying epoxy and applied over the crack and built it up a little too. Don't know how long it will hold but I do know it was still holding as of yesterday afternoon when I talked to Ben. I was happy to help Ben"

[KHE]

12 hours ago, OldCadTech said:

OoO I was under the impression you were looking for a temp repair to get you through the winter months.

I mis-understood, sorry. 

No need to apologize.  If it lasts a couple of months, that would be great.

2 hours ago, BodybyFisher said:

Kevin, this was in an email from CTSV who repaired BenATX's cracked engine, I hope this helps, Ben was able to drive the car from Houston to Austin but he noted that it still leaks. It was a sizeable crack.   If you search BenATX you will find the thread on his cracked engine if you need it.  Feel free to contact CTSV directly, Mike

"I used a combination of marine grade epoxy putty and forced it into the cracks after sanding and cleaning the block. I had drained the engine of as much coolant as possible but one of the cracks was still leaking water. 

Used the putty first to stop the water, then waited for it to set, cleaned again and mixed up some steel reinforced quick drying epoxy and applied over the crack and built it up a little too. Don't know how long it will hold but I do know it was still holding as of yesterday afternoon when I talked to Ben. I was happy to help Ben"

Thanks for the information.  I couldn't tell if the crack went beyond the area I was attempting to seal up - the transmission is in the way.  Hopefully the temp. repair coupled with leaving the surge tank loose allows the car to be driven long enough to buy time to locate a replacement.

[Logan]

Kinda related info about engine blocks and cracking.

The BMW M12/13 racing program started with very used engine blocks. The theory is a used block was relieved of any internal stresses. 

http://www.enginelabs.com/news/engine-myth-urinating-on-cylinder-block-improves-durability/

And another guy ran a used Chevrolet school bus engine block in the 1980 Indy 500. Same reason...seasoned blocks are less likely to crack.

 

[BodybyFisher]

Thanks @Logan that makes me feel a lot better.

The firm in texas that has been cracking blocks is using a 7/16 (I will verify that size) stud into the block but he is freehand drilling and tapping the holes, so I am not concerned with that too much.

Kevins block was big serted.

It is interesting to me that when GM designed the timesert that they seemed to be conservative when they could have gone big.  Why?

Does anyone think that the larger the block is drilled out, the higher the risk of cracking?

Note that Bens block was cracked at #2 (using the texas stud) and Kevins block is #1 (bigserted), the ends of the block.  Coincidence?

I should note that the Northstar Performance stud is also beefy and he has not had any evidence of cracking, but he also uses a jig to accurately drill and tap.

I need to get the sizes of the studs and bigsert

Thoughts?

[Logan]

I'm not sure GM had anything to do with designing the Timesert kits. I think that is Timeserts baby.

No one really reinvents head bolt threads with engine design. Typically about 3 threads are used. Could be M11 x 1.25, M11 x 1.5 or M11 x 2.0. Some Hondas run a M10 or M12 size bolt.

Any engine that uses a aluminum block....will have some pull in the field.

2 versions of Northstars use a M11 x 1.5 head bolt. Same as Toyota 2.4L and some others.

The Toyota 2.4 head bolts also share a very common problem. Pulled head bolts. A bigger problem than Northstars. Toyota has kinda washed their hands of it and have moved on. It is interesting to note on the Toyota blocks...it's typically the 3 rear head bolts that pull. Often found to be little more than finger tight.

The actual Timesert used on both the Toyota and Northstar blocks is the same....11155.

The BS for both are also the same. The BS is used as a second chance and last chance repair. If a BS pulls...you replace the block.

 

It should be noted....GM thread kits are Kent Moore. Kent Moore kits in reality use Timesert tools. They are just packaged differently.

And....there are differences in the kits. So a Timesert J-42385-100 kit is not identical to a Kent Moore J-42385-100 kit.

 

Pic shows difference between standard 11155 Timesert and BigSert

 

 

[KHE]

The Timesert was developed during the development of the Northstar engine in order to change heads in the development testing.  The Bigsert was used when an improper repair was attempted using a Heilicoil.  I repaired this engine with Bigserts because a dealer botched the repair just prior to me purchasing the car.  It's possible the larger diameter of the Bigsert somehow weakened the structure of the block.

[BodybyFisher]

That is what worries me about the bigger diameter solutions.  Norms, studs, etc

[Logan]

Hmmm....hate to challenge the Northstar Timesert development claim....

The patent for Timeserts dates to 1969. Patent 3,566,947.

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=3,566,947.PN.&OS=PN/3,566,947&RS=PN/3,566,947

 

Here is a vintage Kawasaki Timesert kit from the mid-eighties...

http://www.ebay.com/itm/Vintage-Kawasaki-Time-Sert-M8-x-1-25-Repair-Kit-/272422070889?hash=item3f6d9eea69%3Ag%3ApdEAAOSw4shYAT0A&item=272422070889&vxp=mtr&nma=true&si=Mwi4lfw9YGhZQg%2Bk7ehz0t0BDaw%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

 

[BodybyFisher]

Thanks Logan for more info on Timesert development.

I think there exists a belief that GM was involved with the development of the NS timesert because of things the Guru told us.  Is it possible that GM worked with Timesert in its development for the NS?

Based on things the Guru said, it was my belief that GM was involved.  Maybe Kevin and I are got our belief from the Guru?  Kevin?