Cadillac northstar repair

[barczy01]

Have to give a shout-out to all the Cadillac Northstar owners who trust me to do great work and keeping me busy! Also to Bruce with the boat motor project that takes up the whole shop

[Cadillac Jim]

Boat motor???

[barczy01]

I do work on other vehicles besides Cadillac's. It was the first and yet the last Ford engine on my engine stand.

[rockfangd]

northstar engine in a boat.... Rocket boat.

[KHE]

Not sure if he's installing a Northstar in the boat or doing work on the existing Ford engine.

Mastercraft had a ski boat that had a Northstar engine in it from the factory. I remember the guru saying it was a special run of engines and that a dual overhead cam engine wasn't really suited for a marine application. Boats require a lot of torque and power at the low end of the RPM scale where a dual overhead cam engine makes its peak power at the high end of the RPM scale.

Nevertheless, I'd like to see how the Northstar engine performs in a boat.

Marine engines have specific starters and alternators (explosion proof) - I wonder what he's using for the starter & alternator.

[Cadillac Jim]

Probably, a marine starter and a marine alternator.

/duck, tuck, and run

[barczy01]

Still very busy fixing head gaskets and Cadillac's in general. I have had 2 05's Northstar's in a row, one had loose head bolts and another with only 75K the head gasket was eaten alive by Dexcool. The new thread pattern 11 x 2.0 in the northstar block is loosening up over time.

[rockfangd]

I run Dexcool. Do you recommend this?

When I had my engine replaced the shop used the universal coolant. Said they wouldnt touch dexcool.

I know the schedule changes but I change my coolant every 2 years anyway.

I ask this because my seville is only driven 6 months out of the year and is in storage for the other. I mainly worry about it when it is in storage

[Cadillac Jim]

I've heard anecdotes about Dexcool and other OAT-based antifreezes. But just about all manufacturers switched to OAT anti-corrosion coolants in 1995 and the rest soon after, and none have gone back to green, to my knowledge. Most cases of damage have been traced back to running with low coolant for extended periods of time, exceeding the recommended time or mileage rating so that the coolant goes acidic, or other abuse.

I found this in the Wikipedia article on the Pontiac Bonneville:

In March 2008, GM announced that these engines and other GM engines supplied with Dexcool antifreeze coolant might be prone to intake manifold failure and other problems with the cooling system if proper regular maintenance is not correctly performed. After settlement of a class-action lawsuit, GM agreed to compensate owners of many vehicles that suffered damage, regardless of negligence on the part of the consumer, if the consumer can prove damages.

This was referenced to Sadowsky vs. GM, a suit decided in 2008, with the written decision as a PDF file here:

http://www.girardgibbs.com/docs/cases/100_Dexcool%20Long%20Form%20Notice.pdf

In reading the PDF, I see that this applies only to the 3.1 or 3.4 liter V6 with a nylon/silicone lower intake manifold gasket. None of them are Cadillacs. I've replaced that gasket twice in my wife's 1999 Pontiac Gran Am because we didn't keep track of the time the coolant had been in the car. It's expensive because it requires that the pushrods be pulled to get the lower intake manifold off.

My feeling is that GM tells us that if we use the recommended coolant and keep it maintained properly, we won't have a problem. That's been my observation, with the exception of a fellow in Boston that had an ETC that he maintained properly but nevertheless had a head gasket problem at 64,000 miles. Since that is the only case like that which I have heard of, I have suspicions of things like the famous JiffyLube scandals exposed by TV station people and hidden cams that showed that work billed was not performed, something that I have experienced myself.

What I recommend is that if your car came with red (DexCool or red antifreeze) and it has never had green put in it, stay with red and change it every 4 years. If it has ever had green antifreeze in it, put what you like in your car but I recommend red if it came that way, but change it every 2 years or less.

If you have doubts, I read of a way to check your coolant's acidity with a voltmeter. Put one terminal on a good engine or chassis ground and the other in the coolant and if it reads 0.7 Volts or more, change the coolant ASAP. The warning point is at 0.4 Volts.

Acid coolant is going to eat at your head gaskets, particularly if they are against aluminum. In order to get to the head bolt wells and give you a pulled head bolt, some of it must get past the head gasket that way. Even if the head bolt well seals hold, eventually you will get enough head leakage to cause a problem without a pulled head bolt.

The way that people maintain new cars in the last decade or two is to do what they think that they must, and trade them when the lease runs out or they hit about 100,000 miles. That's why there are so many great used cars out there that need a lot of routine maintenance but which are good cars for many years if properly maintained.

But I have never heard of a dealer recommending that someone change their coolant.

[barczy01]

I install the conventional green coolant in my cars when I'm finished. I can't tell you how many engines I have seen where all 20 head bolts snap loose and are tight upon teardown of a head gasket repair. In the end its lack of owner maintenance, not changing coolant, coolant becomes acidic and eats away the head gasket.

As Jim states above nobody really changes coolant. When I was at the dealer back in the day they sold a 30K,60K,90K service. 1997 Cadillac Seville rolls in for a 30K, why change the coolant when GM advertises 100K coolant. So, in the end, coolant was never flushed or changed. Dexcool turns into really bad stuff if not properly maintained and flushed on a regular 2 year service.

[KHE]

The thing most people fail to comprehend is that the coolant is 5 years or 100,000 miles - whichever comes first.

[rockfangd]

Ok thanks.

So as long as I keep to the 2yr schedule dexcool should be ok.

[KHE]

Ok thanks.

So as long as I keep to the 2yr schedule dexcool should be ok.

Yes - because you can only drain about half the coolant out of the system because there are no block drains.

[BodybyFisher]

Do we have a method of checking the coolant's PH? I have heard about using a voltmeter, anyone have a procedure?

How about checking the coolant's PH like we do with pool water, any ideas?

[Cadillac Jim]

I read somewhere about the voltmeter test. If a voltmeter terminal in the surge tank reads 0.7 Volts or more, your coolant is past due. Reading on fresh coolant should be 0.4 Volts or less. It seems to me that the validity of this test depends on what the voltmeter terminal is made of, and that it probably is valid for nickel plated voltmeter probes. Otherwise I would ask a good radiator shop, or go to a big auto parts store and ask for testing kits. I know that coolant tests for antifreeze life are easier to find than test kits for combustion products.

There are multiple problems with going to four or five years on red coolant with an old car. It may have a higher coolant deterioration rate than a new car for whatever reason, you don't change all the coolant when you drain and refill as MAC says, and it may have had green in it at one time.

I would look for a test kit.

[BodybyFisher]

I would like to have definitive testing for coolant. Kevin has brought up an interesting thought that not all coolant is drained out when you drain the coolant, so I think its good to keep an eye on PH if possible, and record it.

[Cadillac Jim]

I did a little looking around and it seems that most testing products out there are marketed to fleet operators, industry, and business, with the emphasis on diesels, large cooling systems, motorcycles and watercraft (vehicle rental people - small fleet operators - and dealers), etc. The test strips are on Amazon so they are available retail. I've not noticed them on the shelves at the local NAPA Auto Parts store, which is the go-to place for a lot of local mechanics, but you should be able to get them at the local Pep Boys, Autozone or other large-store chain.

It seems that the coolant life is tested by checking the nitrite level by evaluating the SCA level (supplemental coolant additive) because the SCA is what protects against corrosion.

The freezing point level, or percentage of antifreeze vs. water, is also tested.

Some test strips check for contaminant level. I'm not sure this is much added value over the SCA testing for gas engines.

Brands that I see out there include:

Penray TS200 (also TS100)

Robinair 75134

Robinair 75234 (trucks)

Hastings CT102

Cool-Trak 311519

Fleetguard CC2602A

Prestone AF-1420

NAPA FIL 4106

Wix 24106

Fleetguard CC2602

Anyone with experience using any of these care to report experiences with them?

[KHE]

Nitrites are used in diesel engine coolant - I don't think they're in passenger coolant and you don't want them in passenger car coolant.

In the case of Dexcool, the organic acid corrosion inhibitors do not deplete over time but the coolant can get acidic so I would think pH would be the be the parameter I'd want to monitor but then again, it is easier to drain and refill every couple of years vs. trying to save a few bucks on the cost of changing the coolant.

[BodybyFisher]

Nitrites are used in diesel engine coolant - I don't think they're in passenger coolant and you don't want them in passenger car coolant.

In the case of Dexcool, the organic acid corrosion inhibitors do not deplete over time but the coolant can get acidic so I would think pH would be the be the parameter I'd want to monitor but then again, it is easier to drain and refill every couple of years vs. trying to save a few bucks on the cost of changing the coolant.

I am thinking more of initial diagnostic work when I purchase a scrap yard Northstar or buy a used car with the NS, I can hear it run, I can test the coolant for combustion by-products and if I can also test the coolant for PH to see how diligent the maintenance was I have a good indication of engine health. Buying an engine with combustion by-products in the coolant ramps up the risk that electrolysis takes place and the price of the core or car drops substantially, acidic coolant can be used as a negotiation point. If you can show the owner the test, it will be influential in the negotiation. The idea is to minimize risk. Sorry, your coolant is acidic and hasn't been changed recently, that is bad and creates risk. Of course they may decide to not sell it to someone as knowledgeable as me at that point. Not necessarily for my personal use.

[Cadillac Jim]

Ordinary litmus paper strips from any chemical supply house can test for pH in the range of interest for coolant. You will need a color test chart to be able to give the pH as a number, and they should also have that.

[BodybyFisher]

I will look for something like that, thanks, it sounds like the pool strips.

I may end up with this

http://www.coleparmer.com/Product/Oakton_pHTestr_10_Waterproof_BNC_Pocket_pH_Tester_35634_14/UX-35634-14?referred_id=778&mkwid=VEuFuFzv&pcrid=%7bcreative%7d&utm_source=bing&utm_medium=cpc&utm_campaign=Shopping_PLA_Main&utm_term=24968650459&utm_content=Ad+group+%231

[BodybyFisher]

Here is a nice writup, I included credit at the bottom

Chemistry 101: the pH of Your Cars Coolant

Weve all been trained by mom, dad and the cars manual to check our coolant level on a regular basis. We may even been good about checking the visual condition and freeze protection level of our coolant. What we havent been told is that the pH (acidity) of our coolant can be far more important than its specific gravity (freeze level) or visual condition. Now that aluminum heads and engine blocks and other components have become as common as iron under the hood, the addition of an acid, such as automotive coolant that has dropped below 9.0 pH, creates a textbook battery. The resulting transfer of electrons can wreak havoc on your water pump, engine block, cylinder heads, head gaskets, heater core, heater control valve, radiator, hoses and every other metal component. Your ideal pH range is between 9.8 pH and 10.2 pH and a system below 9.0 pH can cause extensive damage in as little as thirty days. Once a cooling system has been neglected and damaged, that damage sometimes cannot be undone. In the shop we use the term terminally neglected cooling system to describe a car that has no hope of economical recovery from electrolytic damage. Tom Dwyer Automotive can test your cooling systems pH level and specific gravity free of charge and recommends you perform this test at least once a year.

http://tomdwyer.com/2010/car-information/coolant-ph/

[Cadillac Jim]

I will look for something like that, thanks, it sounds like the pool strips.

I may end up with this

http://www.coleparmer.com/Product/Oakton_pHTestr_10_Waterproof_BNC_Pocket_pH_Tester_35634_14/UX-35634-14?referred_id=778&mkwid=VEuFuFzv&pcrid=%7bcreative%7d&utm_source=bing&utm_medium=cpc&utm_campaign=Shopping_PLA_Main&utm_term=24968650459&utm_content=Ad+group+%231

That looks a lot more focused than litmus paper strips. It may use them, but the strips are just part of the system that Cole-Parmer makes.

[BodybyFisher]

I sent their sales staff an email to verify this this device will do the job. Having something so convenient would be nice, I have something like this to test the salt in my pool.

[KHE]

Here is a nice writup, I included credit at the bottom

Chemistry 101: the pH of Your Cars Coolant

Weve all been trained by mom, dad and the cars manual to check our coolant level on a regular basis. We may even been good about checking the visual condition and freeze protection level of our coolant. What we havent been told is that the pH (acidity) of our coolant can be far more important than its specific gravity (freeze level) or visual condition. Now that aluminum heads and engine blocks and other components have become as common as iron under the hood, the addition of an acid, such as automotive coolant that has dropped below 9.0 pH, creates a textbook battery. The resulting transfer of electrons can wreak havoc on your water pump, engine block, cylinder heads, head gaskets, heater core, heater control valve, radiator, hoses and every other metal component. Your ideal pH range is between 9.8 pH and 10.2 pH and a system below 9.0 pH can cause extensive damage in as little as thirty days. Once a cooling system has been neglected and damaged, that damage sometimes cannot be undone. In the shop we use the term terminally neglected cooling system to describe a car that has no hope of economical recovery from electrolytic damage. Tom Dwyer Automotive can test your cooling systems pH level and specific gravity free of charge and recommends you perform this test at least once a year.

http://tomdwyer.com/2010/car-information/coolant-ph/

He states the pH should be 10 nominally but that is toward the base side. 7 is neutral which is what distilled water would check. It would be interesting to see what the pH of new Dexcool mixed 50/50 with distilled water is.