Well, the "fun" continues...lost coolant, tapping under passenger valve cover, etc.

[ross87t]

I have owned my current Buick a total of 4 months. In that time, I have put maybe 80-90 soft street miles on it. About 55 of those miles were myself, my wife, our 7 year old daughter an our 18 month old son cruising to/from a local car show a few weeks back. Last Friday, I shut the car off at a local store. I return to the car 2 minutes later, start it up and there is a tapping sound (which sounds like it's coming from under the passenger valve cover) and the car feels like it's running on 3-4 cylinders. I'm less than a mile from my house, so I limped it home. Pissed off, I just park it in the garage and go about my weekend.
I have had to add coolant to the car twice since owning it and I did not know where it was going. No smoke from the exhaust and no visual leaks or puddles. Well, it appears the car is low on coolant again. I also popped off the driver's side valve cover breather and there looked to be a lot of moisture in there...with a swipe of the finger, it was kind of a greasy clear/white texture.

I assume my next step should be to drain the oil and look for coolant in the oil? Any ideas of what I may be looking at here? Head gasket? The tapping under the valve cover scares me too. I've had broken rocker shafts on other cars in the past and that is what it sounds/looks like, but the coolant loss really concerns me and has been happening since day 1 of this car being shipped from Maryland.

Time line:
Mid July - Car arrives on a truck at my home.
A few days later (after getting Texas plates and putting a total of about 1 mile on the car) the car won't start. Dead Alternator...replace alternator.
Next day the cam sensor starts acting up...Locate stock sensor, replace the next week.
A few days later...dead battery...replace under warranty.
After finally getting the car in "running shape", I drive it a total of 10 miles. Engine temp is getting near 200°. Check coolant...quite low. Top off coolant.
Put another 50-60 miles on it without issue. The above problem happens. Check coolant...low again!

I now realize the coolant loss problem had to be existing when the car was sold to me and I suspsect the cam sensor issue was also pre-existing. Not really what I expected after paying $16k + shipping for a car off this board.

Sorry for such a long post, I was venting a bit there towards the end.

Any ideas, suggestion on the steps I should take from this point forward?

 

[rmar]

Pressure test it or leak down or just start by changing the head gasket.....Sorry.
Remember you eat an elephant one bite at a time.

As far as the taping make sure it has not wiped a lobe on the cam or the rockers and or geometry is ok while you are there.

 

[Amelio]

That does sound like a head gasket....the tapping noise could be from coolant in the oil either wiping a lob or has gotten into a lifter causing it to bleed down and it can not recover. Does it ever go away or does it stay tapping and the car feels like its missing? If it's the second option then it sounds like the cam went too. Sorry that is a major bummer but I think you will find more than most of us on here have been there some more than other. I have been there many times,I went through 3 flat tappet cams before I went to a roller.

 

[ross87t]

That does sound like a head gasket....the tapping noise could be from coolant in the oil either wiping a lob or has gotten into a lifter causing it to bleed down and it can not recover. Does it ever go away or does it stay tapping and the car feels like its missing? If it's the second option then it sounds like the cam went too. Sorry that is a major bummer but I think you will find more than most of us on here have been there some more than other. I have been there many times,I went through 3 flat tappet cams before I went to a roller.

It's funny you asked me that. It went away twice then came back on 2 separate occasions on my short ride back to the house.

 

[Pronto]

Pull the valve cover and take a look! No sense spectulating on the tapping. As far as the coolant goes, it may be getting sucked into the intake slowly. You could throw in some pills and see what happens. It does sound like your going to have to remove the intake at some point though.

 

[turboclam]

What's the oil pressure read? I assume that the cam is a flat tappet?

 

[ross87t]

Pull the valve cover and take a look! No sense spectulating on the tapping. As far as the coolant goes, it may be getting sucked into the intake slowly. You could throw in some pills and see what happens. It does sound like your going to have to remove the intake at some point though.

No doubt about it. I will be pulling the valve cover. I'm not stupid. Haha.

tuboclam3,
Oil pressure is good. Yes. It's a flat tappet. Edelbrock 5487

 

[Amelio]

if your oil is not milky then you may be ok and the coolant may be going into the intake as mentioned and that is a simple intake gasket fix, as far as the tapping pull the valve cover as you mentioned and see whats happening if it is not moving much it could be a bad lobe or a collapsed lifter. You can also pull the oil filter and cut it open and have a look......cam material is very fine and it will look like a fine dusting of metal. That is a quick and easy way to see if there is a bearing or lobe failure before pulling the engine down. If your oil pressure is good then most likely your bearings are ok and it could just be a lifter or lobe.

Best of luck to you!

 

[ross87t]

The rear main seal has a pretty good leak. I'll drain the oil, pull the pan and have a look in there too.

Thanks.

 

[Razor]

I use a machinst ruler and spin the engine over. All your intake rockers should travel the same amount, all your exhuast rockers are the same.

You can start motor and start unplugging the fuel injectors one at a time till you find the cylinder thats giving you the problem. Once there start inspecting. At least that narrows it down from 6 to 1.

As to the coolant seepage.. good luck. can even be a crack in the timing cover. The best way is to buy a radiator pressure gauge setup that has the pump.. pump the radiator to 20 PSI and start looking for leaks. If the oil pan is off.. that would be a good time to try and spot where its coming from.

 

[GARY HARVEY]

Easy way to determine a dead cylinder is to check for cold exhaust.
3 in 1 smeared on the exhaust is a good tattle tail.

"one bite at a time" (very good).

Check the front rod bearing before you waste too much energy.

good luck btw.

 

[Razor]

Easy way to determine a dead cylinder is to check for cold exhaust.
3 in 1 smeared on the exhaust is a good tattle tail.

"one bite at a time" (very good).

Check the front rod bearing before you waste too much energy.

good luck btw.

Good tip. Another is using an IR thermometer. 30 bucks at Harbor Freight