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Discussion Starter · #1 ·
Hi All,

I am in need of your help in pointing me in the right direction. Here's a little background:

Back in August, my buddy tells me that my car is spitting out black stuff thru the exhaust. I notice that there are black marks on my garage floor. And I get black splatter when I hold paper in front of my exhaust. So who knows how long this has been happening.

About a month ago, my car developed a bad case of misfiring. I did a compression check and noticed that my #2 cylinder is at 142 while the other 3 cylinders are in the 180s. I inspected the plugs and #2 plug was oil fouled. The other 3 plugs were normal.

The misfire was found to be caused by a tear in the rubber connection between the MAF sensor and the intake plenum.

I thought with the misfire cured, I will wait until I have time to deal with the low compression. But a week ago, my radiator ruptured at the top and the bottom requiring a re-core. And after installing the radiator, I went on a drive and within an hour, the bottom radiator hose blows off the radiator on the freeway! I just made it to a service station and they reconnected the hose and refilled the coolant.

I just thought the hose wasn't secured tightly enough when the radiator went back in. I didn't drive the car until today when I went to Willow Springs. The car flew up there beautifully cruising at 4500rpm all the way for an hour. On the drive back, within 15 minutes of getting on the freeway, I smell coolant and the temp gauge is swinging to the right.

I pulled off and was able to get some coolant and re-attached the lower radiator hose. And I idled and warmed up the car for 20 minutes to make sure nothing was leaking and all was OK. I then proceeded to get on the freeway and within 15 minutes, the hose blows off again. This time I wasn't lucky enough to be near an off ramp. So I was flat-bedded home.

Now I can't believe that the hose would "just fall-off". The service station mentioned that somewhere, my cooling system is being over-pressurized thus causing the hose to blow off.

I've never had any problems like this. Might all these problems be caused by whatever is causing the black stuff coming out my exhaust?

What do I need to do to get my car back to its reliable self?

Thanks,

Manny
 

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Wow Manny, when it rains, it pours... Could be a couple of things.

Bad radiator cap that is not "venting" when the coolant in the radiator expands and builds pressure or..... you could have a blown headgasket or cracked head in No. 2 cylinder.

Take the radiator cap off and start the engine. If you see a lot of bubbles, the head or gasket is leaking.
 

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Manny,
I was about to move this thread to the "Cooling" forum, but I am guessing it is "mechanical" after all. It sounds like what Gary has suggested: either a blown head gasket or a cracked head. And a radiator cap that isn't releasing the gas pressure that is being pushed into the cooling system. As RallyBob said in the earlier thread:

RallyBob said:
I agree with Jeff, worn valve guides won't cause low compression. A cracked head can also cause low compression, but that is normally accompanied by increased coolant temps and a highly pressurized coolant system (usually causing coolant overflow).
And not at all like a bad valve guide, which as I recall, was what your mechanic diagnosed your problem as. Time for a new mechanic, and for a head removal. Maybe you could get in touch with Roger Wilson (of "Roger's Opel Engineering" fame) and see if he could help you out with a decent head rebuild, and maybe add some ponies while he is at it. Good luck...
 

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Discussion Starter · #4 · (Edited)
Gary said:
Wow Manny, when it rains, it pours... Could be a couple of things.

Bad radiator cap that is not "venting" when the coolant in the radiator expands and builds pressure or..... you could have a blown headgasket or cracked head in No. 2 cylinder.

Take the radiator cap off and start the engine. If you see a lot of bubbles, the head or gasket is leaking.
Hi Gary,

When I "fixed" the car at the service station, I ran the engine with the cap off for about 15 minutes to make sure all was well. No bubbles. But I'll try it again today. Also, I thought that a blown head gasket would cause water to get into the cylinder and there'd be white smoke out the exhaust. Is this not always the case with a blown head gasket?

Anyways, as I read all the replies, it does sound like it's time to take off the head and have it inspected. That was my reason for asking for Roger Wilson's number. I have the right one but can't get him on the phone. And he has no answering machine. I thought I heard him say that he might be closing up shop. Is this true?

Kwilford,

I think it was me that said "bad valve guides" because I read it in Chilton's. I looked at the spark plugs and found a matching photo. And it mentioned oil getting into the cylinder and it possibly being rings or valve guides. I thought taking the head off would be easier to check first. So I said valve guides.

I also read Chilton's on head removal. And it sounds pretty straight forward with the exception of the 12mm serrated drive. Where do I go to get one of those?

Thanks all,

Manny
 

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Discussion Starter · #6 ·
How long should it take?

Just curious how long you'd think a first-timer should take to remove the head. I just don't want to get started and find out I didn't allocate enough time.

Thanks,

Manny
 

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boomerang opeler
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5,636 Posts
hi manny you want to give yourself a good 4-5 hours first time and then you can work slowly to get used to the layout
only real hard part is the manifold bolts as they get all the heat so they can be a bitch at times
all said and done its only 30ish bolts so not to bad
and if in doubt give us a shout im on far to often for my own good so you will get a reply within an hour or two
 

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Old Opeler
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Manny, About four hours should get the head off for the first time. Be aware that you will need a smaller (8mm) 12-point bit to take the cam gear off the front of the camshaft too. The gear just rests on a special bit of pressed sheet metal attached to the top of the cylinder block - just make sure the motor is at TDC , firing on cylinder #4. The cam wheel "dot" will line up with the notch in the sheet metal shelf and the cut outs in the camshaft will be positioned correctly to allow the removal of the head bolts. Don't move the crankshaft once the cam wheel is disconnected or pistons can damage valves - the idea is not to rotate either the cam or crankshaft while they are not tied together by the cam chain.
 

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boomerang opeler
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a good tip is to tie the cam chain and wheel together so they stay in place
 

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Discussion Starter · #11 ·
GTJIM said:
Manny, About four hours should get the head off for the first time. Be aware that you will need a smaller (8mm) 12-point bit to take the cam gear off the front of the camshaft too. The gear just rests on a special bit of pressed sheet metal attached to the top of the cylinder block - just make sure the motor is at TDC , firing on cylinder #4. The cam wheel "dot" will line up with the notch in the sheet metal shelf and the cut outs in the camshaft will be positioned correctly to allow the removal of the head bolts. Don't move the crankshaft once the cam wheel is disconnected or pistons can damage valves - the idea is not to rotate either the cam or crankshaft while they are not tied together by the cam chain.
Thanks GTJim,

Chilton's didn't mention this. The only thing even closely related to this is a notation to: "rotate the camshaft so that the recesses are vertical to allow installation of the left row of cylinder head bolts."

How do I ensure that the motor is at TDC on #4? I'm assuming I can just rotate the fan by hand to position the motor at #4 TDC? Should I use the distributor rotor to tell when I'm there?

Thanks for the tip baz. I'm guessing a zip tie would do the trick to keep the wheel and chain together.

Thanks again,

Manny
 

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Old Opeler
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Tdc #4

When #4 is TDC on the firing stroke there is a steel ball bearing embeded in the flywheel that is visible through a hole cast in the block extension under the intake/exhaust manifold - look straight towards the back of the car and you should spot it. Also the location pin for the cam sprocket is at 12 o'clock and the distributor rotor will be pointed towards #4 plug wire.
If all else fails just remove the spark plugs and turn the engine over with the water pump belt while holding a finger over the #4 spark plug hole - when the pressure against your finger drops and begins to suck then you are somewhere near TDC on #4 firing stroke.
The "notches" cast into the camshaft to access ONLY line up correctly in this one position - at TDC #4 firing stroke.
 
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