Change 348 cam seal engine in.

I just got my car started a couple days ago after I did an engine out service on my 95 348 spider. Fortunately I didn't have the AC compressor installed yet as I was waiting on my new one to be shipped. I say fortunately because it made it possible to see where oil was leaking near the front of the exhaust cam on the passenger side. I remember while installing the cams I kind of stressed one of the 4 seals at one point, can't remember which of the 4 it was. So I'm assuming worst case although I suppose it could be the cam cover gasket/RTV joint(s).

My intention is to do a little more diagnosis then change the seal if I decide that is the problem. I am pretty sure I can do it with the engine in the car. Here is my plan: Remove timing belt cover top on passenger side. Remove both cam covers. Align engine to top dead center. Place cardboard under bearing caps on the other 3 cams. Loosen the timing belt tensioner (Not sure how I'll do this yet). Hold in place with the 6mm bolt I put in the tensioner base. Jam a rag under the cam pulley/mark it to the belt with white out. Perhaps zip tie it. Unbolt the pulley. Uniformly loosen the bearing caps for that cam. Remove the cam. Replace the seal. Put it back together. Check for TDC alignment. Crank the engine over a few times by hand to check it and start it.

What do you think? Sound like a crazy idea? I think it will be easier since my car is a convertible.

If I feel I can't do it this way in the middle of the job I can always drop the motor.
Brian

 

The timing belt is brand new. It only has about 3 minutes of run time on it. Is there some reason to change it just because I slacken it and re tension it?

 

Also, after careful inspection yesterday, I see a drip of oil on the driver's side also. I bought an inspection camera for $100 at Harbor Freight yesterday. It has a really small camera head, small enough to fit in "most spark plug holes", according to the box. Not that I need it for that at this time. It is pretty slick. I am hoping I can find out exactly what is leaking before I take it all apart. I plan to run the motor this afternoon while inspecting it with the camera. Hopefully I'll find out that it's the gasket corners. I'm hoping for the best but preparing for the worst.

 

Why would I be likely to get the timing off doing what I propose? 4 aligned cams and TDC on the crank = correct timing, no?

 

Thanks that really helps!

 

So you use a dial indicator on a tappet instead of the cam alignment marks? Which tappet? What reading? If you are just looking for valve closure how would a dial indicator help? After all, each valve stays closed for a pretty long time. And how do you get the dial indicator pin on the tappet with the cam lobe in the way?

Also, why would you torque the cam sprockets with an impact wrench? I torqued mine with a torque wrench, to specification. I inserted a screwdriver through a timing pin hole and held it against the head (with a rag underneath). Worked great.

Yes, you can get to the timing pin no sweat with the engine in.

 

Well it turns out yes you can do this. I aligned the cams to them marks, checked the crank pulley for TDC, put cardboard under the center of the other three cams and removed the timing belt cover (couldn't get it out, just out of the way). Then I put 2 zip ties on each cam pulley through the holes over the belt. Then I put a ratchet on the pulley bolt for the exhaust cam on the passenger side. I welded an extension to a pickle fork, placed that over the ratchet and smacked it a couple of times. The cams didn't move but the bolt came loose. Then I removed tension from the belt at the tensioner. Locked it in place with the 17mm bolt. My 6mm set screw didn't really help much with this. I removed the pulley bolt, the cam caps and the cam. I replaced the seal and reinstalled. I was even able to get a torque wrench in there. Cardboard under one cap on each of the 4 cams, zip ties and it held in place while I torqued it to 72 lbs-ft.

I also made a special wrench to turn the crank pulley. I hate to bring up a sore subject but I am all but convinced that I could change the cam belt with the engine in after this experience. My only issue would be whether or not there would be room to slide the ballancer pulley off with the frame in the way. Then again, I don't think I would need it off all the way to slide the belt past it.
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I tried to post this yesterday but was having web issues. The seal was definitely bad, the lip was folded over. However, after replacing the seal I might still have a leak in the area. After running it a little I did see some oil there, but not nearly as bad as before. Naturally I'm thinking I shouldn't have replaced any of the seals at this point as nothing was leaking before I embarked on the engine out.

I am awaiting further testing until my new oil pressure sender arrives.

The drain hole thing has my interest now. My seal housings do have the reliefs, as well as marks on them and marks on the cam covers to align them so the reliefs match up with the drain holes. I like the fact that the seal housings are removable, it made it much easier for me to replace the seal with the engine in. However, it is one more seal/joint and one more potential leak. None of you guys put rtv around these o rings, do you? How about axle grease? I might end up pulling this thing again. If I do might try something like that.