2000 DTS Overheating

[donljacobs]

New Guy here, any help appreciated. 145k, well maintained. Started with upper hose leak caused overheat. Replaced hose and still overheat! Replaced Resevoir, Cap, flushed system, thermostat, pump, fan relays (fans work properly) I turn on heat and luke warm,(90 degree day though). Is this a self puging system? think so. Anyway, no mud in oil, no white smoke, no water out exhaust, no loss of coolant. If I put on AC it overheats real fast, w/o ac slower. Car runs perfect otherwise, again very well maintained. Upper hose gets hot, don't see lower collapsing, I have not checked to see if heater hoses are getting hot. Oh, when going to hot it draws down fluid and sets off low coolant light. When turn off car coolant level returns to normal. This one has me stumped. Perhaps collapsed vanes in radiator? Before I spend on a new one I wish, I knew for sure or could test this one. I am old and can't afford dealers. I took it to a shop and he charged me over $300 bucks to put on a resevoir which wasn't the problem anyway! Again, any help greatly appreciated!

[Ranger]

Yes the system is self purging. Pull the 3/8" purge line off of the top side of the surge tank and put it in the surge tank. Start the car and see if it flows coolant. If so, it is purging as it should.

Anyway, no mud in oil, no white smoke, no water out exhaust

none of the above is a Northstar symptom of a failed head gasket in the early stages and coolant in the oil almost never happens.

no loss of coolant.

That is a good sign.

Oh, when going to hot it draws down fluid and sets off low coolant light. When turn off car coolant level returns to normal.

THAT is strange. What level do you have the coolant at? It should be about 1/2 full.

[donljacobs]

Thanks for your interest. Yes, it is 1/2 full, it goes down to almost bottom and then back up. Guy that charged me $300 for a resevoir said he tested radiator, but I am not trusting what he says. I am thinking next; pull the radiator and put in new, cheaper than going to a shop, I think they guess anyway! I don't know what to do, if it is a blown head gasket, how do I find out? I got to have this car to go to work. From what I read with re-studding and all, it doesn't look like something I am equiped to do. This is a beautiful car, but I don't know if I want to put in the money. I did a tranny last year, struts, rest of front end, all new brakes, MX4s, etc. etc. The car was perfect until that upper hose went, rubbed on radiator and made a hole! How stupid is that? Thanks again for any help.

[RAP]

Thanks for your interest. Yes, it is 1/2 full, it goes down to almost bottom and then back up. Guy that charged me $300 for a resevoir said he tested radiator, but I am not trusting what he says. I am thinking next; pull the radiator and put in new, cheaper than going to a shop, I think they guess anyway! I don't know what to do, if it is a blown head gasket, how do I find out? I got to have this car to go to work. From what I read with re-studding and all, it doesn't look like something I am equiped to do. This is a beautiful car, but I don't know if I want to put in the money. I did a tranny last year, struts, rest of front end, all new brakes, MX4s, etc. etc. The car was perfect until that upper hose went, rubbed on radiator and made a hole! How stupid is that? Thanks again for any help.

[RAP]

Hi, I don"t have an answer to your problem but I recently put in a radiator in my 2000 DTS. After getting prices which ranged from $215-250.00 just for the radiator, I was able to buy a Koyo radiator with oil cooler for $151.00 plus tax. Its part #2369 and I located it through a local radiator shop.

[airmike]

Just an opinion, but I would check the head gasket first. I believe the system will be finding all the weak spots with combustion entering the system and over pressuring. You will get to replace a lot of parts and have committed more money, in case it is a head gasket, and you wouldn't decide to repair it. The cap will vent out excess pressure, but I don't think it can keep up with the exhaust getting into the coolant. The auto parts stores have a kit to test for combustion in your coolant.

[Texas Jim]

Thanks for your interest. Yes, it is 1/2 full, it goes down to almost bottom and then back up. Guy that charged me $300 for a resevoir said he tested radiator, but I am not trusting what he says. I am thinking next; pull the radiator and put in new, cheaper than going to a shop, I think they guess anyway! I don't know what to do, if it is a blown head gasket, how do I find out? I got to have this car to go to work. From what I read with re-studding and all, it doesn't look like something I am equiped to do. This is a beautiful car, but I don't know if I want to put in the money. I did a tranny last year, struts, rest of front end, all new brakes, MX4s, etc. etc. The car was perfect until that upper hose went, rubbed on radiator and made a hole! How stupid is that? Thanks again for any help.

To find out if it is a head gasket... go to your local NAPA store.

They have a kit you can rent to test for exhaust byproducts in the coolant.

That is a sure way to test it.

"THEN" when you know the results.. you make the decision on what you want to do with the car.

[Ranger]

It's called a block test kit. You can borrow one from Autozone or any parts store that has a loan-a-tool program. All you'll have to buy is the test solution. Looks like this. http://www.sjdiscounttools.com/lis75500.html

[donljacobs]

Thanks for your interest. Yes, it is 1/2 full, it goes down to almost bottom and then back up. Guy that charged me $300 for a resevoir said he tested radiator, but I am not trusting what he says. I am thinking next; pull the radiator and put in new, cheaper than going to a shop, I think they guess anyway! I don't know what to do, if it is a blown head gasket, how do I find out? I got to have this car to go to work. From what I read with re-studding and all, it doesn't look like something I am equiped to do. This is a beautiful car, but I don't know if I want to put in the money. I did a tranny last year, struts, rest of front end, all new brakes, MX4s, etc. etc. The car was perfect until that upper hose went, rubbed on radiator and made a hole! How stupid is that? Thanks again for any help.

To find out if it is a head gasket... go to your local NAPA store.

They have a kit you can rent to test for exhaust byproducts in the coolant.

That is a sure way to test it.

"THEN" when you know the results.. you make the decision on what you want to do with the car.

[donljacobs]

Thanks again, Here is where I am: long story short, put on a belt tensioner, car ran perfect 30 miles at hwy speeds, no movement of needle! I was up and down in traffic speeds, Stopped turned around, Started heating up, nothing I could do would stop it. I stopped car let pressure off cap, it cooled, started again on back roads, heated up, stopped, let pressure off cap, cooled down, repeat, So, I will do a block test, but how could I get 30 miles with no over heat? It would not go 2 miles before tensioner without heating up. This is the weirdest thing that I have ever run into.........This car runs strong, very strong. List of things done. new resevoir and cap, radiator removed and flushed, new plastic end put on, new belt, new tensioner, new pump, new thermostat, new top hose, fan relays, fans run right both speeds. no leaks anywhere. I am more than puzzled, but I will do block test tomorrow. I got to think this is simple.....?

[donljacobs]

Thanks again, Here is where I am: long story short, put on a belt tensioner, car ran perfect 30 miles at hwy speeds, no movement of needle! I was up and down in traffic speeds, Stopped turned around, Started heating up, nothing I could do would stop it. I stopped car let pressure off cap, it cooled, started again on back roads, heated up, stopped, let pressure off cap, cooled down, repeat, So, I will do a block test, but how could I get 30 miles with no over heat? It would not go 2 miles before tensioner without heating up. This is the weirdest thing that I have ever run into.........This car runs strong, very strong. List of things done. new resevoir and cap, radiator removed and flushed, new plastic end put on, new belt, new tensioner, new pump, new thermostat, new top hose, fan relays, fans run right both speeds. no leaks anywhere. I am more than puzzled, but I will do block test tomorrow. I got to think this is simple.....?

[donljacobs]

Well, I rented a block tester at Auto Zone, $25 buck, ............no exhaust fumes in coolant!!! The car overheated going to the parts store a mile away, later in the day it over heated going a few blocks. The first time it overheated hardly any heat out of vents, second time plenty of heat out of vents?????? I am thinking about trying "All Data". Anyone had experiences with them? I understand that is where the mechanics go? Anyway, I am open to any all suggestions. Oh, I might add at this time. I have a recently installed magna flow "free flow" Cat on it, so I doubt it is the cat collapsing. Brakes aren't dragging. Was a little windy today though! Thanks again!

[BodybyFisher]

This is a classic purge line CLOG problem. YOUR FIRST LINE "Started with upper hose leak caused overheat. Replaced hose and still overheat"

Now, RANGER said "Yes the system is self purging. Pull the 3/8" purge line off of the top side of the surge tank and put it in the surge tank. Start the car and see if it flows coolant. If so, it is purging as it should"

What was the result of that test?

If that line does NOT flow, you won't be able to fully fill your cooling system because you will have AIR trapped, you will get cold air from heater, you will overheat because of the water pump cavitating and a lack of coolan. Its a classic purge line clog that you are overheating after REFILLING your cooling system

DO NOTHING ELSE, before you check for coolant flow, see RANGER'S post above regarding the purge line checking and follow it, post results here DO NOTHING until you do, do NOT try to blow that line OUT you will create MORE problems, post results here FIRST

[Ranger]

I am thinking about trying "All Data". Anyone had experiences with them?

Alldata is pretty good from what I hear. It is basically an online version of the FSM.

Based on your description I'd say one of two things is wrong. Either the HG is bad or the purge line is clogged, but if you did the test right and did not add any coolant before hand, you seemed to rule the HG out.

[donljacobs]

I pulled the thermostat and now it should run cool, eh? Nope......I pulled the hose off the crossover it is supposed to have antifreeze flow freely......nope......my deduction is block in system. Anyway, I can't do without car any longer, so I took to Northstar Specialist, hundred buck an hour mechanic, I am in the wrong profession, friends. If he can fix this one without taking the rest of my money, I will be happy. This is my second Northstar, the first being extremely dependable, this one ????? Can't beat the ride though!! I will update when I find out.

[BodybyFisher]

You either have a listening problem or a reading problem

I am sorry for you. This is an exchange of information. You did not come back and report the results of your tests of the purge line, INSTEAD you took it to a "northstar" mechanic

You were NOT suppose to take a hose off the CROSSOVER, you didnt read what RANGER posted >>>: "Pull the 3/8" purge line off of the top side of the surge tank and put it in the surge tank. Start the car and see if it flows coolant. If so, it is purging as it should" <<<

We have been very clear here, I even said this >>>: "DO NOTHING ELSE, before you check for coolant flow, see RANGER'S post above regarding the purge line checking and follow it, post results here DO NOTHING until you do, do NOT try to blow that line OUT you will create MORE problems, post results here FIRST"<<<

But you remove the thermostat which is the WORST thing you can do and which can make your overheating worse, but it will NOT lower your coolant temp, then you take it to a mechanic. We said the purge line MUST flow coolant, it didnt flow according to what you said about the hose on the crossover, you were suppose to come back and say, IT DIDNT FLOW, and we would have told you HOW to clear it.... UGH

If you can get your car back from the mechanic do so, your purge line appears clogged if your description is correct. We COULD have instructed you to CLEAR the PURGE LINE, that line clears your system of AIR, if you have AIR and it is blocked you WILL overheat, its so easy a MONKEY can do it,

If you can get your car back, we can save you a bundle of money and aggravation. Expect him to suggest a water pump and radiator change....and it will still overheat, then he will suggest you need head gaskets, all because of a clogged purge line......

Get the car back

[BodybyFisher]

My advice to you is to print this thread out on paper, some people can't read and comprehend on a computer monitor, and go sit on the john and re-read this thread from START TO FINISH, and comprehend it, listen to what has been said in this thread.

Then get your car back

I personally have fixed at least 6 Northstars from overheating by checking the purge line and clearing it

[donljacobs]

You either have a listening problem or a reading problem

I am sorry for you. This is an exchange of information. You did not come back and report the results of your tests of the purge line, INSTEAD you took it to a "northstar" mechanic

You were NOT suppose to take a hose off the CROSSOVER, you didnt read what RANGER posted >>>: "Pull the 3/8" purge line off of the top side of the surge tank and put it in the surge tank. Start the car and see if it flows coolant. If so, it is purging as it should" <<<

We have been very clear here, I even said this >>>: "DO NOTHING ELSE, before you check for coolant flow, see RANGER'S post above regarding the purge line checking and follow it, post results here DO NOTHING until you do, do NOT try to blow that line OUT you will create MORE problems, post results here FIRST"<<<

But you remove the thermostat which is the WORST thing you can do and which can make your overheating worse, but it will NOT lower your coolant temp, then you take it to a mechanic. We said the purge line MUST flow coolant, it didnt flow according to what you said about the hose on the crossover, you were suppose to come back and say, IT DIDNT FLOW, and we would have told you HOW to clear it.... UGH

If you can get your car back from the mechanic do so, your purge line appears clogged if your description is correct. We COULD have instructed you to CLEAR the PURGE LINE, that line clears your system of AIR, if you have AIR and it is blocked you WILL overheat, its so easy a MONKEY can do it,

If you can get your car back, we can save you a bundle of money and aggravation. Expect him to suggest a water pump and radiator change....and it will still overheat, then he will suggest you need head gaskets, all because of a clogged purge line......

Get the car back

[donljacobs]

Easy there Pal, I perhaps did not post that when Ranger said to pull the line at the tank, I did that and there was free flow. Another friend suggested to check at crossover also. I have the car back. The mechanic after thorough testing, three times, says it is head gaskets! As far as radiator, water pump, I alread installed a new pump, thermostat and had radiator taken off and flushed and the plastic end replaced and I have a new plastic tank. I am 65 years old and have wrenched my own cars since I was a teenager. This problem is not what I have experienced in any car that had a blown head gasket. I have done plenty. I really do not appreciate being compared to a MONKEY! You might try de-caf, eh? I have read up on heads on these cars and clearly I am not equiped to do this myself. You have to put new special head bolts in. So, I now have to decide whether I keep it or not. Thanks to the others for all your help!

[BodybyFisher]

Easy there Pal, I perhaps did not post that when Ranger said to pull the line at the tank, I did that and there was free flow. Another friend suggested to check at crossover also. I have the car back. The mechanic after thorough testing, three times, says it is head gaskets! As far as radiator, water pump, I alread installed a new pump, thermostat and had radiator taken off and flushed and the plastic end replaced and I have a new plastic tank. I am 65 years old and have wrenched my own cars since I was a teenager. This problem is not what I have experienced in any car that had a blown head gasket. I have done plenty. I really do not appreciate being compared to a MONKEY! You might try de-caf, eh? I have read up on heads on these cars and clearly I am not equiped to do this myself. You have to put new special head bolts in. So, I now have to decide whether I keep it or not. Thanks to the others for all your help!

Maybe I am misunderstanding something here, NOW you are staying there was free flow in your prior post you said this

"I pulled the hose off the crossover it is supposed to have antifreeze flow freely......nope......my deduction is block in system"

Explain the above statement. The purge line runs from the top of the coolant tank to the crossover, it is involved with the pre-heater on the throttle body. DID you pull the purge line off near the throttle body?

Oh and I am sorry, I did not compare you to a MONKEY, sorry if it appeared that way, the above statement is confusing.... if no coolant flowed your purge line is clogged if that is the "bolt with a hole in it"

[Ranger]

Just to clarify, you don't need "special bolts". You do need to drill and retap the bolt holes and insert them with Timeserts http://www.timesert.com, Norms inserts http://www.huhnsolutions.com or studs http://www.northstarperformance.com, BUT you cannot use the old head bolts if you go with inserts. Either way it is a big job and an expensive one. If you are in the Chicago are I do know of a place that does it for around $2000 if you decide to go that route. Best of luck to you.

[donljacobs]

Easy there Pal, I perhaps did not post that when Ranger said to pull the line at the tank, I did that and there was free flow. Another friend suggested to check at crossover also. I have the car back. The mechanic after thorough testing, three times, says it is head gaskets! As far as radiator, water pump, I alread installed a new pump, thermostat and had radiator taken off and flushed and the plastic end replaced and I have a new plastic tank. I am 65 years old and have wrenched my own cars since I was a teenager. This problem is not what I have experienced in any car that had a blown head gasket. I have done plenty. I really do not appreciate being compared to a MONKEY! You might try de-caf, eh? I have read up on heads on these cars and clearly I am not equiped to do this myself. You have to put new special head bolts in. So, I now have to decide whether I keep it or not. Thanks to the others for all your help!

Maybe I am misunderstanding something here, NOW you are staying there was free flow in your prior post you said this

"I pulled the hose off the crossover it is supposed to have antifreeze flow freely......nope......my deduction is block in system"

Explain the above statement. The purge line runs from the top of the coolant tank to the crossover, it is involved with the pre-heater on the throttle body. DID you pull the purge line off near the throttle body?

Oh and I am sorry, I did not compare you to a MONKEY, sorry if it appeared that way, the above statement is confusing.... if no coolant flowed your purge line is clogged if that is the "bolt with a hole in it"

[donljacobs]

After Ranger said pull hose at tank I did and it flowed freely, at cross0ver it spit and sputtered, but it was very hot. Later when it cooled it flowed. What is happening is a tremendous amount of air, I mean the tank bubbles like crazy gets in the system and it overheats. I purge system, release pressure, until no more bubbles, and it cools down. It will sit and idle all for hours without over heating. Drive it around the block and it heats up. Sometimes gradually, sometime the needle moves in large increments. Like I said, I have never seen anything like it. But no doubt it is getting a lot of air in there, Thanks again! This is a beautiful Black on Black car and I love it, but have been out of work all summer and the $1,100 right now is a killer.

[BodybyFisher]

After Ranger said pull hose at tank I did and it flowed freely, at cross0ver it spit and sputtered, but it was very hot. Later when it cooled it flowed. What is happening is a tremendous amount of air, I mean the tank bubbles like crazy gets in the system and it overheats. I purge system, release pressure, until no more bubbles, and it cools down. It will sit and idle all for hours without over heating. Drive it around the block and it heats up. Sometimes gradually, sometime the needle moves in large increments. Like I said, I have never seen anything like it. But no doubt it is getting a lot of air in there, Thanks again! This is a beautiful Black on Black car and I love it, but have been out of work all summer and the $1,100 right now is a killer.

That is a shame that the mechanic said you have a bad head gasket. Did he say what test he used to determine that?

If your purge line flows when the engine is cool and idling, the air purge line is clear. Do me a favor, when the engine is cool take the cap off the tank, stick your nose in there and get a good smell, do you smell exhaust fumes?

Again, I am sorry about you feeling that I referred to you as a monkey, I was trying to let you know how easy it was to repair this problem if it was clogged. We have seen many Northstars overheat due to a clogged purge line, and based on what you said, it sounded like your line was clogged, and then you took it to a mechanic, so I was upset because if it were clogged, it was an easy fix. So I was looking out for you.

By the way, it would cost a lot more than $1100 to fix that engine if its head gaskets, we usually hear its about $3000 to $3500, the engine must come out, and the block timeserted and engine resealed.

We are seeing a lot more head gasket problems lately as the Northstar is an aging platform. Great engine, getting it reconditioned properly would provide you with a great car, try to save it till you can afford to get it fixed. If you decide to do that, come back and we can help you with getting that done.

[donljacobs]

Thanks for the great input. I do appreciate the help. Today I did the Blue Devil treatment....as a temporary way to get by. I have to have the car for work. I am expecting to be on another contract in the next week or so. I am in Detroit and I found a shop that specializes in Northstar heads and rebuilds and they are advertising a sale on tapping out and putting in special bolts, gaskets for $1,100. I looked them up on the web and they have recommendations and no negative feedback. So, when I get a paycheck or two and I will get it done right. The Blue Devil seems to work, I have been around town today, but not to highway yet. I see no air bubbles in the tank but it has not been pushed. My next project on this car is to rebuild the front lower control arms. I did Arnott struts last year. So, I will look for posts on control arms and perhaps after that R&P and do magnatron. So, I will be posting in the near future. Thanks again to all, it is appreciated!