CAS leaking oil?

[Talesin]

The short version:
I've been told that oil is leaking through the CAS housing. Wouldn't that fry the CAS? It runs fine for the time being, but has passed through at least 4 quarts so far, in the course of three or four weeks. Am I being BSed by someone who doesn't want to take responsibility?


The long version:
The engine in my '90 GSX is a refurb six-bolt with the balance shafts removed; it started leaking almost immediately, but the supplier was happy to fix the leaks (primary fix seemed to be silicone sealant ).

Regardless, the last time I returned it to them, they said that the engine itself wasn't leaking... that it was the CAS (camshaft/crank angle sensor), leaking oil out through the housing, and not just the seal to the head (which was leaking before, fixed with silicone and a new o-ring).
Now given how touchy these things seem to be (water/steam getting in screwing them over), I'd think that oil leaking THROUGH one would fry it and cause a non-start. At the moment the most I get is an occasional split-second hesitation under WOT pulling, usually around 3000-3400 in third.

I can get pictures tomorrow, though I'm also going to try to swing it by my mechanic if he has time. I'd really rather not buy a new CAS, as the cheapest I've found new ones going for is around $400.

 

[Talesin]

Been a while since I posted. My mechanic does agree, the CAS is actually leaking oil through the housing. I'm now confused as to why it isn't dead. And irritable, as it's a $600 from-Mitsu part... or a $450 Bosch part. :b

Anyone have an exploded diagram of a CAS instead of the 'replace with part number ##########' I get from Haynes? If nothing else than to try to figure out if it even HAS any internal seals to leak, or if they put on the wrong size O-ring, allowing it to slip through the rotating join.

Additionally, I'm running 20W50 Pennzoil... I just read the sun visor (for the first time on any car I've owned) and the most it recommends is 20W40. Is this just due to the age of the car, or is it possible that the 20-50 is causing the leaks? I'd always been taught that you use thicker oil when a car starts to leak, to help stop them. Should I swap back to 10W30 on my next oil change?

 

[91gvr4]

There is a seal you can replace, you wanna change that first.

 

[Talesin]

If it's the O-ring that connects it to the valve cover, that was already replaced. It's actually going through the CAS housing join itself. Have a VFAQ or link to instructions? I've been looking, but came up with zilch.

 

[johnk]

My guess would be that it is getting in around the shaft for the spindle. There must be an O-ring on it if you can crack it open. As for losing a quart of oil a week through there I would suggest looking somewhere else. Maybe check your compression your more likely to be burning the oil that fast. There's no pressure at the top of the head and the CAS won't be floating in oil like your oil pan. The only oil up there is what gets slinged around by the Cams. Even if you compression is good look at your plugs if they are wet then you might just have bad oil rings.

 

[1fast97gsx]

When my CAS was leaking oil I was also losing about 1 quart every 1000 miles. I just took it apart and rtv'd everything so oil CAN'T get in there. This is not the proper way to fix it, but it worked for me and was practically free. I recommend going to a junkyard and just getting a new CAS rather than messing with it.

 

[Talesin]

I'll probably do that... still pissed that they put on the o-ring, then plastered the crap out of it with silicone sealant.

Also, a contributing factor is that they didn't run a bead around the oil drainplug when they put it in last.. got a slow drip there. Beyond that, I have to fix the CAS and clean the engine up before I can really SEE where anything else is coming from. The only other is just above the dipstick tube join, along the seam... looks a touch wet.

And a third.. the turbo has a bit of play in it. Nothing too bad, good for another 50K miles, and my mechanic will rebuild it for 300. And the oil return line looked like it had been busted, then braised together again. Minor seep around the reservoir end flange.

No smoke of any kind, under load or at idle. Since I've got 20W50 in it at the moment (going back to 10W30 next oil change), I'm just figuring that it may just be overpressuring its way through.