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My Engine is burning oil, and I’m so frustrated, I think I have had a lot done to prevent and stop it from using oil like a diesel. Let me tell you about my journey so you have the full picture of what has been done.

First off, let me say that I’m not an expert on Engine’s, so that’s why I have had a good friend and very skilled alfa mechanics with a background as an engineer to do all the work.

Secondly, I only use my car for trackdays, its not a daily driver, but I drive it back and forth to the tracks I love to ride. Mainly the Nürburgring.

Step 1. Engine was burning oil, and we suspected valve guides to be the problem. Changed the valve guides, had 1 mm shaven off the head for higher compression, a lot of other components where changed in the head to make sure everything was ok. Modified cam-wheels, so they where adjustable, to make up for the 1mm. had a Dastek Unichip mounted and the car was put on a dyno and adjusted
Everything was working well for at least for 2-3 month, and the engine was burning oil again:eek:. Our theory was that the higher compression accelerated/exposed wear in the cylinders.

Step 2: Well the engine had driven 200k km, so it was probably time anyway. Everything went apart, I had 164s pistons 1:10, new liners, new rings. All went back on, the car was put on a dyno and adjusted. It went up to 222hp on the scale. It’s probably less in real wheel horses, but the point is that it went up from 190 from the first time on dyno, when the Unichip was mounted.
Now the engine was running smoothly, but when the car was on the track driving had, it gave huge oil clouds accelerating out of corners:(. The theory was the compression was now at a level, where and oil catch tank was needed.

Step 3: An oil catch tank was mounted, it helped somewhat but not completely, and I had an extra outlet made in the left side of the engine. That didn’t change anything. After a good weekend on the Ring and lots of oilclouds, the engine was also smoking on the motorway returning home. Now the theory was that the rings couldn’t take the high compression:mad:.

Step 4: The engine was split apart once again, a specialist took a look at the whole engine, and supported the theory. So new liners and new gapless rings from Total Seals was put in. Just to make sure the head was compression tested to reveal if there was leakage, but no. Everything was put back together, Mineral Oil was put in according to Total Seals instruction. Compression test was fantastic as always, but the engine smoked a lot. The theory now was that liners, and rings should settle. The engine felt good and strong.
Burn in period was done, the engine smoked less. But it does burn a LOT of oil. On the motorway to Nürburg (app 900km) the engine was using 3,5 liter, and I was driving with a relaxed right foot!
After a weekend on the ring and 2,5 liter more oil, I discovered some kind of pattern. When hot it smoke more than cold, when idling for minutes and hitting the gas hard it gives a nice smelly cloud. When starting the engine these clouds seems more often to appear when the engine is warm rather than cold.:confused:

Just some extra fact:
I normally use synthetic racing oil 10w-60
I got Greg Gordon stage 2 injectors installed.
It’s a Motronic engine with the S cams in.

What am I missing here? Are compression to high? Is my head ready for attention? would a oil cooler be the next step. Should I just settle and call it a diesel?

Here's the troublemaker:
 

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why dont you try to shift for the original mount for the oil breather?

with the original alfa montage the vacuum in the plenum is used, by the way of the idle circuit, to put the sump in slight vacuum and therefore to evacuate the blow by.

with your set up the sump is maybe slightly too pressurized and the blow by gases stays, allowing oil to go in the combustion chambers...
 

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One thing that sticks out like a pole above water (ask me - I've been there in the past 2 years) - you have now increased vacuum up top with the additional head-work and other weak areas will start to show such as;

1) Heads have been re-worked several times over the years. Valve guides that are pressed in and out (even when heated) will take some aluminium with them as they are pressed in and the aluminium hole starts to "oval"... Now they leak BETWEEN the guide and the aluminium head - I saw it with my own eyes!

A test with the heads off - with the springs out but the valve held in by hand - soapy water in the spring recess around the guide and compressed air on the exhaust port and then over on the inlet-port - bubbles form around the guides at their base (between the guide and the head!!!)

2) Worn valve-stems; the valve-faces may be machined and properly seated, but if the stems are worn "hourglass" where they pass through the guide repeatedly, the motor will suck oil past the guides there - check that spec.

3) For whatever reason between tear-downs you fixed one problem, but now perhaps after the last rebuild the rings didn't seat properly - you need to make compression on that motor within the first 10-20 minutes of the initial start-up...

4) Wrong valve stem seals - black ones versus the green ones. Did you use the German "Goertzie"??? rubbers...?

5) High-lift cams (shim-buckets hit the tops of the guides and seals!? (I have seen this on 4-banger Nords, but I don't know if it is possible on the V6 heads...)

Just me thoughts boss - I have experienced ALL 5 of these issues myself and points 1-4 on these motors!
 

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Thanks for the replies

Napoleon SOLO. I will give that a try, even though it is a little different approach than normally given, when blow by is taken place. At least it is cheap, so I sure will give it a shot. However not much pressure where put at the engine on the highway, and the engine used almost as much here as on the track.

JJ, thanks for sharing your experience, it very useful and gives some good pointers on where to look.

ad 1) actually there was addded some sealing to accomodate this, but that can off course have cracked or been damaged. I have a test done at a local engine specialist, but I will followup with him, if his test would have reveal any leakage.

ad 2) ok I see the path, split that engine once again:eek: it's not your fault, but I feel we have been down that road to many times allready;)

ad 3) I will do that again, but we allready tried that when the engine was in burn in phase and it measured 14-15 bar on a Facom compression tester.

ad 4) Yes Goetzhe was used, black ones on intake and green on exhaust. They have run app. 10000 km since replacement. Could they allready be time for replacement?

ad 5) everything was according to factory standards, but it's sure worth looking for if the engine is to be opened again.

Thanks
 
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