Q: 2000 Buick Century 3.1

Messages
3,903
Location
WI.
Friend just obtained this Buick with 56k from her mother, it probably sat idle for five years ..everything is working but the coolant resivour is low and cruddy looking thinking it must be the factory fill wondering what coolant type it was back in 2000 and what color it was so I can verify and start a R/R cycle. tia
 
Messages
26,175
Location
MA, Mittelfranken.de
This is a dexcool cool system with known LIM issues. I would suggest removing the thermostat, upper and lower rad hoses and flushing it out completely inc heater core. Convert it to old fashioned green with 4 large GM cooling system tabs. If its low the LIM gaskets might be shot already, its a common problem and best taken care of with the Fel-Pro PermaDryPlus set and new manifold bolts. With 56K on it i would do this job ASAP if she is a close friend and get it over with. It will leak, its not a matter of if it will its a matter of when and 14 years is over due.
 
Messages
1,873
Location
NoVA
I would flush the coolant but you can still use dexcool or any longlife coolant. Store brand longlife is cheaper than the "name" brand but will still do the 5year/100k service. Replace the radiator cap as well just in case it has dry rotted.
 
Messages
17,501
Location
Clovis, CA
Originally Posted By: dblshock
coolant resivour is low and cruddy looking
You can make that reservoir look like new again by pouring rock salt inside it with a little bit of water and then shaking it up violently.
 
Messages
14,672
Location
The Old North State
Originally Posted By: dblshock
excuse me, LIM issue?
Lower Intake Manifold gaskets. Known to fail and leak at some point. Then need to be replaced. A google search will tell you all you might want to know.
 
Messages
186
Location
WI
Originally Posted By: sayjac
Originally Posted By: dblshock
excuse me, LIM issue?
Lower Intake Manifold gaskets. Known to fail and leak at some point. Then need to be replaced. A google search will tell you all you might want to know.
This ^ ^ ^ 100% !! Either this just had intake manifold gaskets replaced, or it will need to be... in this vintage it is a certainty - can tell you that from experience at a GM dealership... BurrWinder
 

dblshock

Thread starter
Messages
3,903
Location
WI.
whoa..probably need a shop to do all this ..any idea what the job might run w/labor? Gasket bolts thermostat cap coolant
 
Messages
1,873
Location
NoVA
Originally Posted By: dblshock
whoa..probably need a shop to do all this ..any idea what the job might run w/labor? Gasket bolts thermostat cap coolant
The gasket is the hard one. I would start with a coolant flush and if there is no oil in the coolant and no coolant in the oil keep driving for now.
 

dblshock

Thread starter
Messages
3,903
Location
WI.
now the car will be used heavy in harsh rural WI winters and bi monthy 500mi. trips downstate. is the nature of this LIM failure a sudden catastrophy?
 
Messages
13,389
Location
ROCHESTER, NY
Originally Posted By: dblshock
now the car will be used heavy in harsh rural WI winters and bi monthy 500mi. trips downstate. is the nature of this LIM failure a sudden catastrophy?
Well, yes! No one can answer as to when the gasket will decide to fail. Some gaskets never fail in 200,000 miles but, GM had more than it share of issues with these engines with the intake manifold gasket as well as the head gasket failures in the 2.8L, 3.1L & 3.4L. Even the famous 3.8L had some issues in certain years, unfortunately! Do the flush and fill and go from there! If it fails, get it fixed then. It may never happen! Look for signs of coolant loss over time but, no sign of coolant leakage on the ground. Most likely the coolant will go through the exhaust system. IDK if I said that right!
 
Messages
13,389
Location
ROCHESTER, NY
And, oh yes, don't lose any sleep over this. I am sure that you must have a very nice car. And these engines do run very well and make great power/torque all day long, all while getting quite good fuel economy. smile
 
Messages
186
Location
WI
I agree with the advice posted previously. I am not trying to be a fear monger, just saying that the likelihood of them being bad "at some point" in the vehicles' life is very great. I would also flush it out (many of those also had factory "stop leak" installed that would brown up the bottle with a brown residue and cake it on the sides. If it is at all oily in the bottle (which they usually will get) it is time to keep an eye out for consumption and repair any leaks ( external or internal ) as needed to keep it in good running condition. BurrWinder
 
Messages
2,434
Location
Oconomowoc Wi
My sons 2003 Monte Carlo SS with the 3.8 V6 is at 99K miles and on the original gaskets. I originally purchased the car at 48K miles and at that time did a full flush and replaced with long life green coolant. Last week I replaced the thermostat(at 98.5K miles) and did a radiator drain and fill. The coolant still looked like new... Knowing that GM had this issue has made be paranoid about the coolant level and I check it all the time. I do keep the coolant level in the reservoir about an inch above the hot mark(When engine is cold)... I have a little red mark at this level so that I can check it after the car has sat overnight. I was told that having a slightly overfilled reservoir will help prevent air getting into the coolant system. That was known to be a contributing factor in the failing gaskets... I also replaced the radiator cap every 3 years with a 10230 Stant cap.
 
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dblshock

Thread starter
Messages
3,903
Location
WI.
I don't live close by her so she's taking it in to a local indy for an inspection...I just sorta freaked when I couldn't open the radiator cap by hand then all the crud inside the reservoir bottle. Thx for all the advice.
 

Al

Messages
19,256
Location
Elizabethtown, Pa
The gaskets tend to fail slowly. Do a Blackstone Oil analsis. And if the Potassium say is say greater than 10 the gasket is on its way. But it will not (likely) fail suddenly.
 
Messages
9,808
Location
New Jersey
These engines are good get the dex coll out completely and use green anti freeze and use 4 gm seal tabs after flushing with water. Some of them have piston slap but they run a long time i have seen many with over 200,000 miles
 
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