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Discussion Starter · #1 · (Edited)
As mentioned before while removing my new modified 2L from my engine test stand , I had noticed evidence of failed oil seals. All the intake ports were oily, some oil dripping down the valve stems, and trails of oil leaking from every exhaust guides. After installing the engine in the car it always omitted blue smoke, at first badly and more recently much less. But still I knew this problem would need attention sooner or later. Why didn't it show any evidence of this problem while on the test stand I'll never understand. A real pitty because the engine is running so well.

So I decided to order all the required parts and fix the problem while old man winter still grips my Province with extremely snow and cold.
 

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Discussion Starter · #2 · (Edited)
Ya I know. Lots of sooty deposits on the pistons and combustion chambers. While disasseming the head found more problems. Number one cam bearing has damage.

A bit disappointing to say the least.
 

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Discussion Starter · #4 · (Edited)
Thank you for your kind words Gordon.

Can't help but wonder how or why new guides, valves, and seals could leak. And why did the cam bearing fail? Very unsettling considering the engine only has about 8 hrs on it.
 

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Sorry to read of this, Viny. I'm sure someone more experienced then I will come along with some help. But in the meantime, does the oil hole in the cam bearing match up with the oil gallery?

Some interesting reading on this thread: http://www.opelgt.com/forums/opel-e...ns/5806-stock-solid-cam-vs-hydraulic-cam.html, especially Keith Wilfords discussion and questions in post 14. They discuss the different types of stem seals along with cam bearings.

Hope this is of some help for you.

Mike
 

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I was going to mention oil starvation but only one cam bearing would be a fluke I think, but that bearing definitely did not get enough oil. Doesn't explain the oil leaking in the intake, I want to say if it was a GTS head, the gal editor from Hotrod magazine got a head that had several seals damaged from installation. I haven't had any issues with the four heads I've got from them though
 
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Sorry to read of this, Viny. I'm sure someone more experienced then I will come along with some help. But in the meantime, does the oil hole in the cam bearing match up with the oil gallery?
Mike
Yeah, I thought the same but on the other hand the first bearing is usually properly aligned with the bottom passage as it is visible. If that is the case, the cam bearing would be properly lubricated. Upper passage is not visible unless the plug get removed, so that passage is often misaligned. However, that should not affect the first bearing lubrication. :confused:

I wonder if there was some accumulated grit in the head oil passage. It is always worth removing oil plugs, cleaning the passages and replacing plugs with pipe plugs.

Vinnie, if you or your machinist need the tool for installation of Opel cam bearings, let me know and I will send it to you.
 

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Discussion Starter · #11 · (Edited)
-Head was built and assembled by a local and very reputable engine shop.
-Everything was lubed with cam break in grease.
-Oil pump was spun with a drill and the crank rotated t'ill oil came out at every rocker.
- Bearing holes lined with oil galleries.

On a positive note the cam is in perfect shape, lifter are fine. No damage on anything else to report. I'm a little concerned of worn valves, or guides causing the leaking but only time at the machine shop will conclude that.
 

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Well that blows, I'm with you in spirit man as I've been down a somewhat similar road myself and understand the pain of having to pull a freshly built engine
 

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Discussion Starter · #13 · (Edited)
Well that blows
Does it ever.

So I'm home alone while my girlfriend goes bar hopping with her friends. With no plans to do it sober!
And I'm quietly investigating my big valve head issues.

So.................
-All cam bearing are damaged the same way.
-Cam looks ok but I measured all bearing surfaces and ended up with 1.927, 1.917, 1.912, and 1.906. My original cam has the exact same numbers but with 96 000miles.
Is this normal? Haven't found anything in my original Opel tear down book. Doesn't seem right to me.

Another question, should you be able to compress a hydraulic lifter? My new ones stay compress so you can't push them down further. I looked at my old ones and only one was compressible by hand. Is this normal?

Other observations.

Gary, I m not sure if they were semi finished or not. I thought they were but maybe...

All the cam lobes measure the same and are in spec. Oil pressure was 2.5 at 1000rpm
Thanks you all for the support and feedback.
 

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So.................
-All cam bearing are damaged the same way.
-Cam looks ok but I measured all bearing surfaces and ended up with 1.927, 1.917, 1.912, and 1.906. My original cam has the exact same numbers but with 96 000miles.
Is this normal? Haven't found anything in my original Opel tear down book. Doesn't seem right to me.
Yep the ID of the cam brgs. tapers downward...front-rear.
 

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Discussion Starter · #15 ·
Thanks Dan.
 

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Viny - Is your head by chance a "Delta" head? (would have a triangle cast on it) Those used different cam bearings.

Did the head have a lot of gunk and sludge on it before you took it to the shop? If so the oil passages to the bearings may have been blocked with gunk after the head was hot tanked.

Did the machine shop remove the caps on the oil passages and clean them out?

Have you brought it back to them to see if they have any ideas why all this happened?

As Dan said, the bearings taper down front to back so the cam can be installed easily.
 

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Discussion Starter · #17 · (Edited)
Viny - Is your head by chance a "Delta" head? (would have a triangle cast on it) Those used different cam bearings.

Did the head have a lot of gunk and sludge on it before you took it to the shop? If so the oil passages to the bearings may have been blocked with gunk after the head was hot tanked.

Did the machine shop remove the caps on the oil passages and clean them out?

Have you brought it back to them to see if they have any ideas why all this happened?

As Dan said, the bearings taper down front to back so the cam can be installed easily.
Gary the head is a late model 70 head with hydraulic / 4 bearing. I don't think it's a delta head. I did look for a triangle casted on it. Their is none.

Plugs were removed gallery cleaned and replaced with threaded ones.

The engine received regular oil changes it's entire life, and to my surprise had practically no sludge
. When I primed the engine with a drill powering oil pump. Lubricant seemed to flow easily throughout the galleries and to the rockers.

I've only removed the head two nights ago, and yes the next step is machine shop.
 
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Usually when cam bearings get destroyed its because of one of two things. Too much spring pressure, or leftover crap in the oil galleys.

It's the reason I started removing the oil plugs and rocker studs in all heads years ago. Hot tanks CANNOT get rid of everything. It coagulates/hardens up in the oil passages and only comes out after a few heat cycles of a running engine. If there's glass bead residue in there all hell breaks loose inside the engine.
 
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Discussion Starter · #19 ·
Your may be right Bob. The damage is very smooth (no gauges or lines) and is only apparent on the bottom half of the bearings. Wouldn't debree damage all around the bearing?
 

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Discussion Starter · #20 ·
Late last night I removed the rear cam cover to get a better look at bearing #4. It has by far the less damage. #1 definitely has the worst of it.

So number one has the most damage. Two is worst then three , and number four has much less damage. To that rules out oil starvation. As number four should have had the most damage if that was the case. It also explains why the lobes and lifter don't have visible damage.

What does this mean? As Bob has already mentioned, contamination!
I'm convinced very fine debree caused the damage. This explains why the damage is only on the "loaded" side of the bearings where the oil wedge was the thinnest. Whatever caused it was fine enough not to damage the upper halfs of the bearings.

Pictures are of one threw to four.

I've appreciated everyone's time and input.
 

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