348 engine out major

A look at the timing specs for a 348 with catalytic converters says.

Intake:
Opens - 12º before tdc
Closes - 56º after bdc

Exhaust:
Opens - 54º before bcd
Closes - 10º after tdc

Meaning, my cam marks are right on the money. Spot on for a 348 with cats. I also checked the intake cam marks, and the result was the same. Intake cam opened at 12º before tdc. Cam marks dead nuts on the money.
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I love the wooden meat skewer on the dial gauge. For dinner tonight you can bar-be que kebob's with it. You have topped 348 gearbox "especial tool numero veintiseis." There is no one of higher stoogeness alive on this planet.
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Makes perfect sense, thanks. On my Porsche, I always went with the TDC mark on the flywheel.

 

Hey Ernie, what size ring nut socket is that? Need to put it on my list of tools to get..

 

I have no idea George, I borrowed it.

 

^ 28mm available here: Ricambi America : The Ferrari, Maserati, and Lamborghini Parts Specialists

 

Thanks Daniel! My wish list keeps getting bigger and bigger!

 

Ernie, it is a proper assumption to say that the cam timing adjustment is limited to the dowel holes within the cams and pulleys? That is, without machining your own pulley?

I'm just wondering what happens when "between holes"? Or are the factory holes sufficient to allow a small degree change?

 

If it is in between holes, you remove the pulley, turn it one belt notch, and now you have a bunch of new holes to play with. Essentially what Ernie did when he had to adjust that one cam just a hair.

 

The dowel holes on the cam are just fine for making small adjustments. If I'm remembering this correct, each dowel hole will adjust the timing about 1/2º.

Here is the chart from the shop manual for the pulley, and the cam dowel holes.
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Lamborghini chose to extend the holes all the way around the camshafts making repositioning the sprockets unnecessary.
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So much nicer to work with..

 

Also the dowel pins are internally threaded making adjustments a bit easier.

 

Tell me about it!

Trying to pull out the dowel when there was tension against it was SOOO frustrating. you have BARELY anything to grab. It would have been so nice to just unscrew it.

 

End cutting pliers like these are the best thing I've come across for removing the dowels. Without them it's an exercise in frustration.

They usually have them at most tool stores.
SK Hand Tool 18507 7" End Cutter Pliers

 

A dowel that is internally threaded is called a "pull dowel". The purpose is the ability to get it out of a blind hole.

I assume when you say that it makes adjustments easier, you mean since you can remove it and place it in another hole?

 

Yes

 

Makes no sense to me why you guys would have issues with the pins. You need to relieve pressure on them and they slide right out. No force or swearing is needed.

 

Sometimes the pins are a little rusted on the older cars, and some cars were a very tight fit to start off with. The later cars have it much easier - 355s, 550s, etc. - than earlier cars like the 308.

 

what an amazing thread wow
good job

 

Not really a big problem. I was merely pointing out that with a Lamborghini it is quite easy to insert a small screw into the dowel giving you something to hold onto when extracting it. A much bigger issue is the holes in the camshaft. I can't imagine why they did not continue them full-circle. Frequently it seems like even one or two more holes would do it. It's a nuisance to remove the pulley and belt and reposition them.

 

I never believed that one could lock and swap belts with any accuracy. I have always advocated cog removal as Ernie has shown. That frees up the pins. Requisite cleaning ensures access to all holes. You set up cam as Ernie has shown but I would add that you want the cam hole to be in the middle range of the cog holes so that you can adjust. That avoids Ernie's gotcha that mitchell reported the solution for. Then you cam time and see if you are on or off. If off you don't need to pry the pins off but grab the cam shaft and wiggle and the pin will free with little more than finger pressure. You have to grab the shaft anyway to adjust the off timing and test the timing in the needed hole. That's just the process.

 

These are carpenter's pliers (i believe). Very handy for removing dowels

 

Thanks for the explanation. I'll be sure to pass it on to the guys at the Ferrari dealership / restoration shop where I used to work (and time cams day in and day out).

I'm not sure why you're making a point of this. I merely posted a link to a tool that folks will find very useful.

 

Sorry not trying to put down your experience or offend you. I've only done this for thirty or so years not as a pro. I see the problem from the perspective of a non-pro trying to help non-pros. I can see how this problem can be a pita to non-pros trying to up their game from cam setters using assembly marks to cam timers with degree wheel and dial gauge. You are trained, we are not. If you were a non-pro it would be easy to loose site of the goal and get caught up in minutiae. If one fails to understand the shaft needs to be moved to adjust the shaft position anyway (from years of lock and swap) one could be stuck on forcing the pin out instead of relaxing the pin by moving the shaft. You see, our perspectives are different.