mj1pate

At the tail end of my timing belt water pump job and wanted to make a few notes here. I've used some of the excellent write ups as guides but I want to mention something that might help in timing precision (at least insofar as the timing marks by themselves will assist ).

After wrapping my new belt starting at the crank sprocket, counter clock wise around the cam sprocket circuit, I made sure that the belt was as snug as I could make it, particularly between the two cam sprockets.

After applying tension on the belt via the rebuilt tensioner, and turning the crank several revolutions until the crank was top dead center, I noticed several things. 1) the driver side cam sprocket notch lagged but was barely aligned with the mark on the back plate. I attribute this to the unavoidable initial slack Between the right cam sprocket and the crank sprocket, regardless how tight I tried to initially make the belt. 2) the passenger cam notch also lagged, a bit more so that the notch was barely just outside aligning with the back plate mark. Maybe a half tooth off for that sprocket.

I think the slight difference between the alignment between two cam sprockets existed since the last timing belt job. My initial belt span between the 2 cam sprockets was *tight*. The inter cam sprocket timing at top dead center with the old belt is something I should have made better note of initially. I could have tried to account for that during the new belt install.

The slight lag between the drivers side cam sprocket and the crank sprocket could have been improved by common sense. There will likely be marginal slack between the right cam sprocket and and the crank sprocket until the tensioner is initially adjusted and the belt is turned the first several revolutions. From my previous days replacing timing chains, the rule was advance the right most cam gear slightly ahead of its mark, so that when the marginal slack is taken up during the first revolution, the crank sprocket will catch up with the cam sprocket .

Anyway, the guides are super... Just try think things through in a logical sense as you go thru the steps. It can save some time.

zekgb

All you are doing with the timing gear marks is getting within a half tooth or so of time as the gear has a couple of teeth worth of adjustment where it affixes to the cam spider. To get the final timing correct you need to either follow the procedure in the WSM or use the 32Ver after a period of rotating the engine using the starter to settle the belt.

By the way, it's nice to see you still around and posting - we bought our cars at the same time and I actually came close to buying your car as the seller was local to me. Also neat that we seem to be doing the same set of maintenance jobs simultaneously as well, though yours is running better than mine at the moment

mj1pate

Dan did good work. I recently let him know the old shark is still in good working order. But 30 years is what it is. Last year mine received. a massive electrical refresh . Within a few weeks the last of all the lines containing flammable fluids will have been replaced. And of course, there's some kind of refresh every year. We must love our hobbies :-)

zekgb

Dan is a good guy though he was annoyed with me that I didn't buy his car after having spent some time with it (was a weird situation where he temporarily ended his eBay auction and I figured he had sold the car locally in the meantime.) Also interesting that we both did coast to coast trips home after picking up our cars instead of having them shipped. I think you had a few more issues early on than me, but I've more than made up for it recently. Good luck on getting your car buttoned up and back on the road.