| Author |
Message |
Jeff 77 GTB (Jbk)
Junior Member
Username: Jbk
Post Number: 53
Registered: 4-2001
| | Posted on Thursday, February 28, 2002 - 6:16 am: | |
Verell, yeah I was thinking about that. I went out last nite and checked and seals will fit over the flange (the engines out of the car so it was easy to check) so I can do change them from either end. I'm still considering which way to go. I'm going to see if the seal kit I bought has the orings, that might make the decision for me. I don't really want to pull the cams if I don't have to. |
Verell Boaen (Verell)
New member
Username: Verell
Post Number: 37
Registered: 5-2001
| | Posted on Wednesday, February 27, 2002 - 9:32 pm: | |
Jeff,
If you have to pull the pulleys, you must replace the o-rings around the pulley bolts.
----------------------------------------------------------------------------------------------------
This is what the mechanic that performed the pre-sale 30K service on my 308 QV didn't do. Nor did he fix it in 3 trips back to him. Finally I got P#$$* O@@ and pulled things apart myself.
The bolt holes were also used to bore main oil passageway the length of the cam. This passageway has full oil pressure on it. If the o-rings aren't sealing properly, you'll get a 6-pointed star of oil streaks from each point of the bolt head, out to the pulley's rim. The oil will then overflow the rim & get slung lots of places, most notably the cam belts. (It did!!!) |
Jeff 77 GTB (Jbk)
Junior Member
Username: Jbk
Post Number: 51
Registered: 4-2001
| | Posted on Monday, February 25, 2002 - 6:31 am: | |
Verell, Paul, Good points!! Thanks for the advice. I do have the plastic pulleys so I'll leave them in place and change the seals from the other end. I'll only pull them if I need to readjust for timing when I change the belt. Thanks again. |
Verell Boaen (Verell)
New member
Username: Verell
Post Number: 29
Registered: 5-2001
| | Posted on Sunday, February 24, 2002 - 9:28 pm: | |
Jeff, Paul's absolutely right.
Don't remove the pulleys unless you have to.
I got all wrapped up in answering your question & didn't look at the problem you're trying to solve.
I had to pull my pulleys because the o-rings sealing the bolts were leaking. If I remember right, I don't think the seal will go over the flang the cam pulley mounts to. |
Paul Newman (Newman)
Junior Member
Username: Newman
Post Number: 83
Registered: 12-2001
| | Posted on Sunday, February 24, 2002 - 9:10 pm: | |
As far as I know, you have to remove the cams to replace the seals. When the cams are out, you slide the seal on from the opposite end so you dont have to remove the pulleys. If your pulleys are plastic, I wouldnt remove them for fear of breaking them. Im leaving my pulleys on. If your gears are steel, go ahead. Some 308s had a hex behind the cam gears(you can see them with the cam covers still on) and others did not(like mine). With the belts in place, an impact gun will loosen them and should be fine for retorquing then recheck your belt tension. |
Verell Boaen (Verell)
New member
Username: Verell
Post Number: 27
Registered: 5-2001
| | Posted on Sunday, February 24, 2002 - 9:05 pm: | |
Yes, use the belts to keep things from turning while breaking the bolts loose/torqueing them down. I don't think there's any other way to hold the cams in place against the necessary torque.
Once you've got the cam belt covers off, Make certain the car is in 5th, & lock the park brake to keep the engine from turning. DO NOT TOUCH THE CAM BELT TENSIONER TILL THE PULLEY BOLTS ARE BROKEN LOOSE.
BREAK BOLTS LOOSE, BUT LEAVE THEM IN PLACE
-------------------------------------------
At this point in time, you just want to break the bolts loose, not remove them. (The bolts seal the oil passageway down the center of each cam, so be prepared to catch about 1/4 cup of oil when you remove the bolt.) I've done it a couple of ways:
a)(The hard way)Break the bolts loose with a long breaker bar(or torque wrench), and a short socket.
b)(The easy way)Use an air impact wrench to break them loose. You have to be quick on the trigger to keep from spinning the bolts all the way out tho.
You want the bolts to loose enought so that they can be removed with out putting much torque on the pulleys, yet tight enough so that the pulleys can't slip off the cam until you've locked the cams down & backed-off the belt tensioner.
LINE UP THE MARKS
---------------------------
Once you've got the bolts broken loose, release the brake, put the tranny in neutral, pull out the spark plugs if you haven't already, and rotate the engine to line up the crank & camshaft marks. (You can turn the engine over with the spark plugs in place, but it takes a lot of force. Also, while doing it the socket can slip off of the crankshaft nut, and the breaker bar will break your finger between it and the A-Frame edge before you can catch yourself. (Ask me how I know.))
TIP: Before lineing up the marks, make sure they're very visable. Clean the mark areas on the cam & flywheel with lacquer thinner, & let it dry. I then use a very small brush to spread white paint around each cam mark. The black mark is left very visable. I had trouble finding the flywheel marks at all. I ended up holding a small wire brush against the flywheel while the engine was running to clean it up. Once I found the marks, I filled them with white paint, let it partially dry, & rubbed the paint that overflowed outside the groove off, leaving paint in the groove.
LOCK THE CAMS IN PLACE
----------------------
Once you've got all the marks lined up, You want to lock the cams into place so they won't accidently move.
L-SHAPED ALTERNATIVE TO MATCHBOOK COVER
---------------------------------------
Folklore says use a matchbook cover under the middle cap on each cam to lock it down. (This works, but it's dangerous as it's darned easy to forget that it's in there & put things together with it still left in place.) Instead, cut an L-shaped piece of thin cardboard from something like a cereal box or milk carton. The long arm of the L is a 'flag' for visability. It should be long enough to hang out over the area where the cam cover mounts. It need only be wide enough so that you can see it easily, & yet be strong enough so you won't accidently break it off. The short arm(about 1-1/2"long by ~1" wide) goes under the cam cap, just like the legendary matchbook cover.
NOTE CAM-PULLEY ALIGNMENT
-------------------------
Now is also a good time to draw a picture of the position the locating pin on each cam pulley is in. Also, scribe thru the pulley's empty holes to mark the cam itself. The original cam-pulley alignment is either going to be spot-on, or very close.
NOW RELEASE BELT TENSION
---------------------------------
Go ahead with backing-off/removing the tensioner.
BTW, If you haven't already seen them, here are a couple of URLs with descriptions/tips on belt replacement:
NOW REMOVE THE CAM PULLEY BOLTS & PULLEYS
------------------------------------------
ANOTHER TIP:
If you have the plastic cam pulleys, be very very careful to not put any force on the pulley rim. It breaks off very easily. Also, don't forget to check the base of the rim for cracks indicating impending failure.
Ric Rainbolt's instructions on how to change timing belts:
http://www.expensivecar.com/timing.htm
Pointers to FerrariList eMAIL posts by people doing a belt change:
http://www.ferrarilist.com/forum/read.php?f=3&i=9&t=9
Hope this helps.
Good Luck & let us know how you're doing,
Verell |
Jeff 77 GTB (Jbk)
New member
Username: Jbk
Post Number: 50
Registered: 4-2001
| | Posted on Sunday, February 24, 2002 - 7:41 pm: | |
Anyone know the proper way to hold the cams steady when removing the pulley attachment bolts? At least on my 77 there's no hex or other flats I can see that can be used to hold them. Will the belts by themselves provide enough resistance for removing and retorquing the bolts? I want to change the cam seals while I'm replacing the belts and need to take the pulleys off. |
|