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Coolant under valve covers Malibu 2000


Capt.torres
11-11-2009, 03:18 PM
I have been working on my dads 2000 malibu. The car was putting out a lot of white smoke. I thought it was the LIM gasket. I replaced it last week with the new fel-pro kit. I only put RTV on the two ends not on the gasket as per gaskets saying no sealant. Put the car together and was still smoking. Today I disassembled again and when I took the valve covers off there was coolant puddled up around the springs. How is the coolant getting there? Head gasket or did I do something wrong with LIM gasket. Thanks

manicmechanix
11-12-2009, 01:08 AM
It could be the headgaskets. You probably should've done a compression test before you tore it down. you were so close to being at the headgaskets when changing the IMG. Are you sure it's new coolant, How long has it ran before you noticed coolant in the oil under the valve covers?

You might want to run a compression test or get one of those coolant tester kits from NAPA that test for combustion blowby in the coolant.

Capt.torres
11-12-2009, 08:56 AM
I am going to do a compression check now before I pull the heads. Can I do compression test with LIM off but rockers still in place? What should compression psi be? When a LIM is leaking does the coolant get under valve covers I have quite a bit of coolant under covers. I let the car run for thirty minutes but was still smoking with water coming out the tailpipe and a slight miss. Thanks for any help.

rhandwor
11-12-2009, 12:37 PM
I would use a radiator pressure tester and run the engine with pressure on the tester. If the gage pulsates the head gasket is leaking. A compression test normally will point a leak but not always. A Napa test kit or oil analysis will also pin point the problem. If water is coming out the exhaust pipe it apparently is leaking. Look for a bad plug and if anti freeze blows out you will be certain.

manicmechanix
11-12-2009, 03:40 PM
I am going to do a compression check now before I pull the heads. Can I do compression test with LIM off but rockers still in place?

Yeah you could, but you risk shorting out a wire like to the alternator. You should run the test before you take anything apart.


What should compression psi be?


I think it should be in the 140-180 range. You want to see consistency between cylinders.

When a LIM is leaking does the coolant get under valve covers I have quite a bit of coolant under covers.

Yes it does. But what I was wondering is did you have coolant under the valve covers before you took off the LIM and did you clean it up and change the oil and PCV valve?


I let the car run for thirty minutes but was still smoking with water coming out the tailpipe and a slight miss. Thanks for any help.

So has the car only been ran 20mins since replacing the LIMG? I think you need to run it a little longer and do more testing before you tear it apart again. I think rhandwor had good suggestions with the coolant pressure tester etc. I would do that first, then Napa tester, then pull plugs and examine them for coolant, then run compression test and maybe have an oil analysis run as needed to determine if it does have a leak.

Capt.torres
11-13-2009, 05:59 PM
I probably ran the car for 45 min after replacing Lower manifold gasket. I drained the oil but did not replace pcv valve. The coolant was under the front valve cover (a pretty good amount of coolant)when I removed it to be able to remove intake for the second time. I did not use rtv on the water passages only on the two ends maybe had something to do with it. Will work on it tomorrow I'm back down to the heads so I think I will pull them tomorrow.

rhandwor
11-13-2009, 06:26 PM
I would have the heads pressure tested at a machine shop if it was my car.
After everything is cleaned lay a flashlight flat on the block and look for cracks between cylinders.

manicmechanix
11-13-2009, 07:54 PM
I probably ran the car for 45 min after replacing Lower manifold gasket. I drained the oil but did not replace pcv valve. The coolant was under the front valve cover (a pretty good amount of coolant)when I removed it to be able to remove intake for the second time. I did not use rtv on the water passages only on the two ends maybe had something to do with it. Will work on it tomorrow I'm back down to the heads so I think I will pull them tomorrow.

Well I think you should've changed the oil, along with the PCV valve, before running it after replacing the LIM gasket. You are not really suppose to put RTV anywhere else but the end seals so that is fine. I think you should've also ran it some with the new oil and coolant and tested for a blown head gasket with the steps previously mentioned before tearing it down again. I think you should've done that before tearing it down in the first place too, but that's all water under the bridge now since you tore down the manifold again.

If I were you I would have the heads pressure tested like rhandwor said, inspect for cracks, and warpage, but I wouldn't bother with having the heads machined. They will probably just mess them up. Good luck.

Capt.torres
11-13-2009, 08:06 PM
I did change the oil just not pcv valve

dpalomaki
11-14-2009, 05:55 AM
Perhaps one of your new LM gaskets did not seat correctly and you still have a leak? As noted, only need the RTV at the two ends.

manicmechanix
11-14-2009, 03:58 PM
I did change the oil just not pcv valve


OK got it, you changed the oil before running it. Do you think it's possible there was residual coolant in the oil, or did you clean the engine out and all the oil in the coolant got in there in the first 45 mins of running?

You could still run a compression test on it even with the intake off if you are careful. Just tape up the alternator battery terminal, and unhook the PCM, ignition and fuel inj fuses.

I'm sure you know this but it is very important to completely clean the LIM gaskets mating surfaces on the heads and LIM and torque the LIM bolts to the proper sequence and torque.

Capt.torres
11-15-2009, 05:19 PM
Finally finished :). I pulled the heads and the head gaskets had failed on cylinders #2 and on the other side on #5. Put it back together and smoking stopped within five minutes. Car is running fine but feels like its missing a little at idle but seems to be less and less the more I drive. Only have driven about 45 min. Thanks for the help. Any thoughts on the little miss? :)

manicmechanix
11-15-2009, 08:58 PM
Well you seem to be pretty quick at doing these tear downs:). I just wonder if any of the heads had some warpage? Did you check them for that? Well assuming the engine mechanicals are oK now, there's so many things that could cause a slight miss from ignition to injectors being dirty it's hard to say. You might try running a big bottle of Techron in the gas to see if it helps.

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