[Josh King]

Hello all, its been a while since I've been on here, which probably is a good thing because it means I haven't been searching for how to fix problems on my old Caddy... Anyway, about 3~4 weeks ago coolant started disappearing and since I've had a few minor leaks since when my head gaskets were originally fixed I figured it was another minor issue, well, the system's been pressure tested and there's no leaks which leads me to believe that the head gaskets are going again. They were initially fixed (changed?) around 105,000 miles by the Cadillac dealer here in Terre Haute, IN with the Northstar Performance Head Studs, the car now has about 172,000 miles on it. I remember the dealer warrantied their work for like 30,000 miles or something around there. I'm wondering if there is any other random speculation as to what the issue could be or if the Northstar Performance warranty of 5 year/100,000 (both of which I'm inside of) covers head gaskets on all engines with their kit or only work done at their shop.

The current plan is to drive the car until they go, and I can't really justify dumping $1500 into a car with this many miles and being worth only what it is. I know these cars aren't cheap to maintain but time two on head gaskets is kinda the where I feel like admitting defeat.

 

[basscatt]

Hello all, its been a while since I've been on here, which probably is a good thing because it means I haven't been searching for how to fix problems on my old Caddy... Anyway, about 3~4 weeks ago coolant started disappearing and since I've had a few minor leaks since when my head gaskets were originally fixed I figured it was another minor issue, well, the system's been pressure tested and there's no leaks which leads me to believe that the head gaskets are going again. They were initially fixed (changed?) around 105,000 miles by the Cadillac dealer here in Terre Haute, IN with the Northstar Performance Head Studs, the car now has about 172,000 miles on it. I remember the dealer warrantied their work for like 30,000 miles or something around there. I'm wondering if there is any other random speculation as to what the issue could be or if the Northstar Performance warranty of 5 year/100,000 (both of which I'm inside of) covers head gaskets on all engines with their kit or only work done at their shop.

The current plan is to drive the car until they go, and I can't really justify dumping $1500 into a car with this many miles and being worth only what it is. I know these cars aren't cheap to maintain but time two on head gaskets is kinda the where I feel like admitting defeat.

========================
maybe you are jumping to conclusions -

have you done a BLOCK TEST?

 

[Innovator]

This could be bad news for a lot of people.

 

[Submariner409]

That's unfounded speculation at this point. We have no feedback on running temperatures, aggressive engine exercise temperatures, exhaust gas condition, cylinder block exhaust gas test, or several other cooling system diagnostics that need to be performed before hanging your hat on gloom and doom.

"Losing coolant" can be as simple as a defective pressure cap seal or pressure spring. A pressure test won't reveal a bad pressure cap: The cap is on the workbench during the test.

Anything is possible, but all the cards aren't yet on the table.

 

[Josh King]

I apologize if I've appeared as a bearer of bad news, I was mainly hoping for more speculation as to what the issue could be in sort of a brainstorming as to where the coolant is going. I DO NOT KNOW FOR CERTAIN THAT it is the head gaskets but here are the certainties I do know as of right now:
--The car has run fine up until approximately four weeks ago with minor coolant leaks here and there but no major issues.
--Coolant is disappearing to somewhere, I keep having to pour in Dexcool and there are no puddles under the car
--The cooling system has been pressure tested and no leaks were found
--I have yet to check the oil for coolant but will be doing so later this week
--I have not pressure tested the block and do not really plan on it at this time as I don't have the capability to do it myself right now and unless a mechanic or dealer is going to do it for fairly cheap
--There is the sweet, sweet smell of burning coolant in the exhaust and visible vapor from the tailpipe upon start up that sometimes goes away sometimes does not, and it is independent of environmental temperature
--A sizable vibration has also developed on startup that goes away once the engine is at temperature, I don't think this is related but I do not know

This is what I have for as far as signs of issues, I am hoping that the collective experience and knowledge of this forum may be able to give me other ideas of things to check and rule out before further investigation (such as the block test) into the head gaskets.

 

[MoistCabbage]

Were the crossover gaskets changed when the block was studded?

In any case, you're not going to get any closer to an answer without some diagnostics. Northstars don't mix coolant and oil, and a pressure test isn't going to tell you anything. A block test is cheap and easy.

 

[basscatt]

I was mainly hoping for more speculation
as to what the issue could be
in sort of a brainstorming
as to where the coolant is going.
WHY -
why waste your time - and quite frankly - ours - on speculation -
when two fast and easy tests could solve the mystery -

pressure test the cooling system -
and do a BLOCK TEST -

 

[Ranger]

Disappearing coolant, sweet smelling exhaust and rough idle on start up are all HG symptoms.
Are you overheating? If so, it's time for a block test after an overheat episode. (A "block test" checks for exhaust gases in the cooling system. It is not a block pressure test.)
Don't bother looking for coolant in the oil. There won't be any.

 

[arctic_man]

My car is getting the head gaskets replaced again too. Engine sitting on the floor of my garage. 3 snapped studs. First stud snapped and put a hole in the valve cover. I knew after that it would only be a matter of time... Finally got the engine out after 6 more months or driving it and 2 more snapped. These were studs from Tim Carroll. I actually just got my replacements from Jake today since Tim stopped making them.

Tim thought they might have been over torqued, but all other studs are holding just fine. Torqued to spec. The other 7 studs on the bank were all torqued correctly as well...

 

[Submariner409]

I do not believe that Tim was manufacturing his own Northstar head studs. He most likely contracted with outside machine shops and probably had several quality swings and contract changes. His early posts on the subject, when his shop was in Washington state, addressed several quality and supply problems - after he elected to discontinue use of the studs manufactured by NorthstarPerformance.com and strike out on his own. I believe that's the approximate story, although some in depth sleuthing would turn up old threads on the subject. It's all still in this site.

Bottom line: If your Northstar Cadillac is in good to excellent condition other than a perceived head bolt hole problem, it's well "worth" doing a good stud/gasket job on. $2400 - $4200 ???? Whoop-de-doo !!! It's a $50,000 car ....................

 

[97EldoCoupe]

HG's can fail regardless of what repair method was used. $20 head gaskets are designed for a purpose: To do a job for a certain period of time. It would be nice if they lasted forever- but we're still dealing with an open deck, aluminum engine block. I blew the HG's on my Eldorado a second time. Keep in mind, It saw 130MPH frequently and a lot of abuse. I used it as a test car, I pushed the limits.

If I built an engine for myself again and expect to put it through abuse like that, I'd install MLS. We do sell Flat-Out gaskets.

Right now; because of the amount of "knock-off" studs that were in the market; one type of product cannot be blamed for anything. If the studs snapped, that is a problem with the temper of the steel. I'm quite positive the OP has my product in his block. I'd just need to check sales records.

My 5 year warranty covers repairs done in-house. I can't warranty the work of other shops, I have no idea what they're doing for surface prep.

I'd like to see the tear-down. Moreover; I'd like to see this vehicle come to my shop for the repair. To the OP, I'll make you a good deal if you can drive to Ontario.

The fix for this, is simply remove the head, clean the surfaces, check for flatness, install a new gasket and go. The studs will need to be checked for stretch, if they check out ok, they don't even need to be removed.

FWIW, A lot of gaskets on the market are manufactured differently. I trust the repair was done with Fel-Pro, but who knows. I'd prefer the OP contact me.

 

[97EldoCoupe]

I care about my customers. A lot. And I have 100% confidence in my product. I've been to Terre Haute, and dropped by the dealer and shook hands with the service manager and the guy installing our product.

We do manufacture our studs in house from USA steel. I just returned from Minnesota picking up another load. This is what we manufacture the studs from.

This is 41xx chromoly cold-formed steel, batch heat treated to our specifications, a particular tensile strength that allows for the thermal expansion and contraction of the engine block and heads, without loosening up or crushing the head gaskets. It's precision ground after heat treat and then we machine the blanks and cold-roll the threads into the stud on each end. Because of the batch heat treating (in 12 foot lengths) by a steel mill, the quality is consistent.

In this photo there's enough steel to make enough studs for 300 Northstar engines.

 

[arctic_man]

I do not believe that Tim was manufacturing his own Northstar head studs. He most likely contracted with outside machine shops and probably had several quality swings and contract changes. His early posts on the subject, when his shop was in Washington state, addressed several quality and supply problems - after he elected to discontinue use of the studs manufactured by NorthstarPerformance.com and strike out on his own. I believe that's the approximate story, although some in depth sleuthing would turn up old threads on the subject. It's all still in this site.

Bottom line: If your Northstar Cadillac is in good to excellent condition other than a perceived head bolt hole problem, it's well "worth" doing a good stud/gasket job on. $2400 - $4200 ???? Whoop-de-doo !!! It's a $50,000 car ....................

I ordered mine when I believe he had his lathe machine down in Texas. Either way, I have Jake's now and am repairing it again. But I just wanted to share my brief story.

 

[maeng9981]

Should have no problem with Northstar Performance studs. Two Northstars still running strong after 4 and 3 years.

 

[97EldoCoupe]

Harry are you back in the USA yet?

 

[maeng9981]

Harry are you back in the USA yet?

Not yet, but will be back in July or some time near that.

 

[Ranger]

That was quick.............. or it seemed so from here anyway.

 

[maeng9981]

That was quick.............. or it seemed so from here anyway.

It was, we are only required to serve 1 year and 9 months, after that you're free to either go or continue on.