How to hold cams while torquing timing pulley retainer bolts?

I'm degreeing the cams on my 308 QV. Once I have adjusted the timing, how do I hold the cams/pulleys in position while I re-torque the retaining bolts?

 

I lock the flywheel starter teeth with a large screwdriver, through the timing mark acess cover.

 

Sounds like a good use for the old belts: a toothed strap wrench for torqueing Ferrari Cams Drives. Now Some engineer on the forum just needs to design one?

 

Pin cams with matchbook covers under 2-3 cam caps. You need very little force on the cam cap covers to hold the torque of the cam bolts. It works 100% of the time been doing it for 25 years on ferraris...never any damage.

 

OMG,,, Billy your a Geniiiiiiiooooooouuuus.

Edwardo

 

The matchbook thing makes me nervous. Is that really the way it's typically done?

When doing that, how much do you use? Just a strip at the top, or enough to cover most of the bearing cap contact surface?

 

I've done it that way and it works great. Definatly one of those things that comes with grey hairs or from someone with way more experience. I relied on the latter.

 

It is so simple even a caveman can do it. All you do is take a matchbook cover or the paper that wraps a single edge razor blade is absolutely perfect. You tear the matchbook cover off and then in half. Then put the cover under the cap and allow a nice 1/2" piece to stick out from the cam. You do this so that when you check things you make double darn sure to SEE and remove the cover. Then you tighten the caps down just with hand pressure as if you are screwing into drywall to hang a picture and don't want the screw to rip out. That's it no damage. Tighten your bolts and then remove the covers and spin motor by hand to make sure all is ok. That's it. If your 2 covers don't provide enough torque locking then do 3 covers or 4 covers.

 

3 or 4 covers? Holy smokes man, that's thick! I just took a strip of paper doubled-over and it was enough to hold it there no problem
Image Unavailable, Please Login

 

I found another photo:
Image Unavailable, Please Login

 

I think he means 3-4 cam caps, not 3-4 layered matchbook covers.

I have used this technique as well and it works perfectly.

Birdman

 

OK, thanks to all. I'll give that a try.

 

It is so simple even a caveman can do it.

Oh sure, first it was insurance and now we aren't smart enough to work on our own cars!!!

Oh look there's a dinosaur tooth...

 

With all due respect, I'll just stick with my screwdriver. I don't want to be the guy the who posts about cracking my cam cap! (And that would be just my luck) I just don't "feel lucky".

 

How can you crack the cam cap when you only tighten it by hand?

 

Go for it! I'm not smart enough to know if the screwdriver that stops the gears from turning and thus is transmitting the force of the cam bolt torque to the rubber T-belt is a good idea. I'd hate to damage the Tbelt teeth and then throw the belt. I think the caps that take 5000rpm are much stronger than the Tbelt so I'll just stick to the matchbook cover method.

 

I've heard of the matchbook method several times and through a combination of being dense and not focusing on the discussions have not been able to figure it out. Thanks for detailing it and the photos. I am a richer and happier person now. I look forward to having this knowledge in my arsenal when the time comes.

 

Some people are ham-fisted.

 

But remember to remove the matchbook covers afterwards.....it might sound funny but I remember reading a post about someone opening up their engine and finding the mashed up matchbook covers...

 

Lol, yeah man. Im sure it happens quite a lot!

 

Well that's why I said leave some tails sticking out so that you can see if any covers are left. We can foolproof a proceedure but there is always a better fool. Many people do not like this method I have preached since ferrarilist. I also use hammers! Anyway to each his own. Good luck to the op.

 

I just caught this thread. It brings back fond memories. I agree with you FBB. I used this same technique on my 308s and 328. IMHO, it provides the most safe and secure method. Moreover, it provides the perfect excuse to check and re-torque all the cam retaining caps.

 

WWWWWaaaaaaaa HHHHHHHaaaaaaaaa
Someone said "HAM FISTED."
(He was right.)

If you are,,, "ham fisted," lame or just plain unlucky.... get away from my Ferrari and my tools.
If you don't know, WTF, you are doing around a F Car,, like in an F1 car,,,
,
,
,
,
,
get away or put your hands in your pockets.....!

AND,,, ha ha,
Too bad,

(even ENZO knew his limitations.
He didn't build his own motors.)

Edwardo
Mechanical Dude
Mechanical designer
Cal Poly, SLO
(Whatever, , if you can't wrench,, don't start on a F-Car..)
Image Unavailable, Please Login

 

I will not be drawn into a tiresome, sophomoric, exchange. You work your side of the street, and I'll work mine. I will say that the use of a strap wrench, made from an old timing belt, as suggested by "BillyD", sounds like the best idea to me.

 

I think he was joking

Along the idea of your strap wrench, when I did my engine-out rebuild nine years ago, I removed the cams from the heads and to remove the pulleys from the cams I took one of the old belts (I had the new ones already at that point in time, so I had no fear of doing the next step...), I cut a section of it that matched the circumference of the pulley, wrapped the pulley with it, then took a chain Vise-Grip (see: http://www.irwin.com/irwin/consumer/jhtml/detail.jhtml?prodId=IrwinProd100322) to hold the now protected pulley and spun the retaining bolt out with an impact wrench. Piece of cake.

I don't know what others have done to tighten these camshaft pulley bolts, but the paper-under-the-cam-cap trick wasn't sufficient to hold the cams in place for me, as the tightening torque required is quite high (I believe it's 80 lbs-ft). My method was to use a pin-spanner wrench locked into two opposing holes behind the pulley mounting flange on the cam, rotated the engine until those holes would make the pin-spanner rest against a stout object on the cylinder head (belt cover stud boss, or the other camshaft), and was then able to apply the torque to tighten up the cam bolt. Naturally, the tightening action is opposite the rotation of the cam, so the pin-spanner has to rest perfectly against the object to prevent any rotation of the cam. It took many attempts of rotating the crank over to get everything to line up properly... You don't want any slack otherwise the cam will slip under the belt when tightening and totally f--- things up.