Timing Marks on 308 Cam

I tried posting this earlier, but I guess I screwed up somewhere. So, I'll try this again.

I am in the process of changing the timing belts and other misc. hoses and fluids on my 84 308. This service had been performed just prior to my buying it, but that was 4 years ago and it has an oil leak around the cam seal. The car has always started easily, idled good, and ran good, with the exception of a miss/backfire at 6-7K rpm. It doesn't see that much so I never really worried about it.

Got the cam covers off and then lined up the PM 1-4 mark for TDC. Upon inspection of the cam alignment marks I found the front 2 cams were dead on. The back two, however, were not. The intake cam mark has not yet lined up and the exhaust is past. I will post some photos to make sure I am looking at this correctly, so when it goes together the timing is right.

Is there any reason all of the marks should not line up? Could this cause the high RPM miss? Does it look like a belt slip, or screw up by the shop that previously changed the belts? Any input/suggestions are appreciated.

I'm sure I'll have other questions as this project proceeds.

Thanks

Donny




This one isn't very clear but it shows that pointer is on the mark.

Hi Donny,

Just so that we are clear... I added some red marks where I think I see the cam marks. Verify that this is what you are seeing.

JL

Donny,

It is my understanding that the cam marks are lined up, then the belt is put on and the tensioner released (Use the old belt to do this). Pay attention to how the cams move when the tensioners are released. When the slack is taken out of the belt, the cams will move a little bit. The trick is to start with the cam marks slightly off and see where they end up once the belt is tensioned. The cam marks being dead on before tensioning is not really that important. Where they line up after tensioning is important.

I hope that makes sense.

How can they be off? Who knows at this point. Probably whoever did the last belt change did not check the marks after the tensioners were released. Purely speculation at this point and doesn't really matter.


JL

Thanks Jeremy. I should have done that before I posted it. You are exactly right.

I will be removing the cams to replace the seals, but just wanted to verify the proper alignment before taking them out.

Tonight I'm going for the belt covers!!

Sounds like fun.

Should be interesting to see how that effected how the car runs.

Hi Paul,

I'll bet it makes a noticeable difference.

How's the little bambino?


JL

Baby Dino is doing great- thanks for asking.

Today's progress report.



Everything's off and ready for cam removal. Any words of advice at this stage? I'm concerned with flying parts, if the cam is under tension. Also I am wondering what is the best way to remove the cam pulley from the cam once it's out?

I also have to pull the bearings off the tensioners, get it cleaned up and press the new ones on.

After these 2 items are done, and I'm satisfied with the timing marks I plan to do some cleaning and hose replacement. I didn't realize how bad the cam seal leak was.

Mark where the pulley went on the cam before removal.
Assuming the pulley is like a 2V engine.
There are some wrench flats on the cam- close the dist drive?
Bend back the lock washer from the bolt that goes thru the pulley.
Use an impact to remove the bolt.

Yea- looks like you need some gunk off- check out the alternator.

Donny:
When I did it, I made a couple of straps to hold the cam down while you remove/install the caps.
I used 2 pieces of 3/16 X 2 X about 7 inchs HR steel. Drilled 2 holes to fit over valve cover studs and glued a piece of 3/8 plywood to protect the cam.