My Cooling System What A Chore
JB601
08-14-2008, 02:56 PM
I feel as if it is my obligation to share my experience with the community since I gain some much knowledge, insight, and research from these posts. Excuse the long entry, but if it saves you time, money, and most important, save you from a headache then it’s worth it. Well here goes. About 3 weeks ago I noticed coolant leaking from underneath the engine bay. Me, being a die hard shade tree mechanic, I popped the hood and didn’t see any leaks. So I start my 3.4 and still no leak. Needless to say I shut the hood and continued on my way with this leak in back of my mind. I finally made it home, popped the hood and noticed a pen size hole in the little bitty hose that runs from a metal pipe attached to a housing that is attached to underside of the water pump to another metal pipe that runs parallel to the exhaust manifold. I was like simple fix right?…….nothing is ever simple when it comes to the 3.4. Then next morning I tore into it. I had to remove the purge valve that runs to the A.I.R. pump, the passenger side fan, the lower radiator hose and the housing that was attached to the water pump. On top of that the 4 inch hose didn’t want to come off. After cutting the hose off I was able to replace it with some standard heater hose. I snapped and bolted everything back in place, fill up my coolant, crank her up just to find the clamps on the hose were not strong enough hence it was still leaking. I tore everything back down and installed new clamps. No more leaks right…..remember this is a 1996 Monte Carlo Z34 with a 3.4 DOHC. A few days later I spotted another leak. This one is coming from the housing I had to take off to gain access to the hose. This housing is attached to the lower radiator hose and seems if it might be able to contain a thermostat. So I tore everything apart again and since this housing doesn’t have an official gasket, I used a thermostat housing gasket my 79 Impala, a lot of gasket maker, and let it set. Snapped everything back together and that leak is fixed…….but it gets better.
I try to keep my Monte running as good as a 1996 can. I’m always under the hood cleaning something, fixing something, or flushing something. Even with a 195 degree thermostat installed it has a very hard time heating up anywhere close to ½ ways on the temp gauge. I started noticing that it was now staying at ½ and the fan was switching on way more that it used to and the overall cooling system wasn’t cooling well as it had before those leaks. I decide to flush the system. I flushed the system as I have in the past with my vehicles until the only thing left was nice clean water. I filled it back up; bleed the air out…… now I have no heat and the temp gauge is running a little over ½ ways. I grab a new t-stat (195 degree oem) and rad cap. Flush and fill again, now it’s running almost ¾ of the way. No oil in water, no water in oil. As I was looking it over once more I find another leak coming from the bottom of the water pump. We all know what that mean, time for another water pump. I run down to AZ and pick up a very nice water pump. (Thanks to these posts I know what to look for in a water pump prior to buying it). After cutting my hands up pretty bad I finally get it installed. Once again I flush, fill and bleed the system. Still same issue, but now she is running right on 1/2 way mark on the temp gauge. This is still unacceptable since before all those leaks it would stay at ¼ or less.
After further research, I uncover that Dex-Cool and the Green stuff don’t mix and it will cause sludge. I clearly remember this green, orange, and brown mixture flowing thru the rad when I first bought the car in which I flushed it immediately. I came to the conclusion that is either going to cool or I will have to trade it off. Once the cooling system goes, just say bye to the engine. After spending close to $100 on simple flushes and coolants, I grab me a bottle of Zerex Cleaner. Flush all the coolant out and just ran the cleaner and water for 3-6 hours of actual drive time. I done as instructed and decide to take me a trip around town, thru the next couple of counties and visited some family. I started to hear these sounds coming from under the glove box (heater core) that sounded like rusty water flowing. Like my coolant system was full of old rice or small peeples. Plus the temp gauge was going haywire. Something was doing something. After about an hour of driving I let it cool and look under the cap to find the horrible, nasty looking bluish brownish, greenish sludge. No way, I have flushed this thing 4 time and came out with clean water.
I continued driving till I get to the 3 hour mark. I let the engine cool off, removed the t-stat and start to flush it again with some Zerex rad flush (not the cleaner, the flush) I was horrified at what came out. At first I got a ton of old orange dex that eventually led to a brown sludge, not water, sludge that turned black there for a minute. I completed that flush and started another one with straight water. It took almost an hour to see clear water.
After 4 flushes with a flushing product my system was still clogged and dirty. When it was all said and done I went back with the normal green stuff because of the horror stories I’ve read about Dex-Cool. I threw in a bottle of Bar Stop Leak, the kind with the little pellets. I always do that to help keep the water pump and the system lubricated and it also helps to have it in there just in case a small leaks creeps up. Plus there could be some small internal leaks from the extreme procedures I just put my engine thru. Bleed the air out old school by leaving the rad cap off and watching the bubbles also used the 2 bleeders then installed my 180 t-stat back in. Now my system runs so cool. I believe the coolants were mixed when I bought the car and just sat and cause a blockage, rust, and everything else negative to an efficient cooling system.
If you are planning a flush or troubleshooting a cooling issue please be advised that there is a difference between a flush and cleaner. Even after 4 flushes I still have a ton of junk and sludge built up. It will not hurt to run a cleaner thru your system every now and then. Just pour it in a day or 2 before you plan to flush your system out and watch all the gunk it will get out. Oh, I really didn’t want to trade my car so I’m glad it worked. Hope this helps, thanks for all the posts.
I try to keep my Monte running as good as a 1996 can. I’m always under the hood cleaning something, fixing something, or flushing something. Even with a 195 degree thermostat installed it has a very hard time heating up anywhere close to ½ ways on the temp gauge. I started noticing that it was now staying at ½ and the fan was switching on way more that it used to and the overall cooling system wasn’t cooling well as it had before those leaks. I decide to flush the system. I flushed the system as I have in the past with my vehicles until the only thing left was nice clean water. I filled it back up; bleed the air out…… now I have no heat and the temp gauge is running a little over ½ ways. I grab a new t-stat (195 degree oem) and rad cap. Flush and fill again, now it’s running almost ¾ of the way. No oil in water, no water in oil. As I was looking it over once more I find another leak coming from the bottom of the water pump. We all know what that mean, time for another water pump. I run down to AZ and pick up a very nice water pump. (Thanks to these posts I know what to look for in a water pump prior to buying it). After cutting my hands up pretty bad I finally get it installed. Once again I flush, fill and bleed the system. Still same issue, but now she is running right on 1/2 way mark on the temp gauge. This is still unacceptable since before all those leaks it would stay at ¼ or less.
After further research, I uncover that Dex-Cool and the Green stuff don’t mix and it will cause sludge. I clearly remember this green, orange, and brown mixture flowing thru the rad when I first bought the car in which I flushed it immediately. I came to the conclusion that is either going to cool or I will have to trade it off. Once the cooling system goes, just say bye to the engine. After spending close to $100 on simple flushes and coolants, I grab me a bottle of Zerex Cleaner. Flush all the coolant out and just ran the cleaner and water for 3-6 hours of actual drive time. I done as instructed and decide to take me a trip around town, thru the next couple of counties and visited some family. I started to hear these sounds coming from under the glove box (heater core) that sounded like rusty water flowing. Like my coolant system was full of old rice or small peeples. Plus the temp gauge was going haywire. Something was doing something. After about an hour of driving I let it cool and look under the cap to find the horrible, nasty looking bluish brownish, greenish sludge. No way, I have flushed this thing 4 time and came out with clean water.
I continued driving till I get to the 3 hour mark. I let the engine cool off, removed the t-stat and start to flush it again with some Zerex rad flush (not the cleaner, the flush) I was horrified at what came out. At first I got a ton of old orange dex that eventually led to a brown sludge, not water, sludge that turned black there for a minute. I completed that flush and started another one with straight water. It took almost an hour to see clear water.
After 4 flushes with a flushing product my system was still clogged and dirty. When it was all said and done I went back with the normal green stuff because of the horror stories I’ve read about Dex-Cool. I threw in a bottle of Bar Stop Leak, the kind with the little pellets. I always do that to help keep the water pump and the system lubricated and it also helps to have it in there just in case a small leaks creeps up. Plus there could be some small internal leaks from the extreme procedures I just put my engine thru. Bleed the air out old school by leaving the rad cap off and watching the bubbles also used the 2 bleeders then installed my 180 t-stat back in. Now my system runs so cool. I believe the coolants were mixed when I bought the car and just sat and cause a blockage, rust, and everything else negative to an efficient cooling system.
If you are planning a flush or troubleshooting a cooling issue please be advised that there is a difference between a flush and cleaner. Even after 4 flushes I still have a ton of junk and sludge built up. It will not hurt to run a cleaner thru your system every now and then. Just pour it in a day or 2 before you plan to flush your system out and watch all the gunk it will get out. Oh, I really didn’t want to trade my car so I’m glad it worked. Hope this helps, thanks for all the posts.
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