Like this?
Or like this?
Or is this all that matters?
So far I haven't found anything in the literature other than lining up the timing marks.
All that matters are having the dots aligned. Either camshaft position is o.k.
By the way, your camshaft gear looks a little worn. Sort of a large backlash showing. Mine is probably worse however and only makes noise at certain speeds.
Cam rotates at 1/2 of the crank. If it is either way it is the same.
Good question for those who have not been inside an engine though.
J
One way will put your timer timing out by 180 degrees.
Compression Stroke or Exhaust Stroke. No problem otherwise.
Is Kerry's timer statement correct? It sounds like it might be especially if Steve's puzzled by it. If it is there's a correct position for the shaft beyond aligning the gear marks. Never did a gear what aligns the gear on the camshaft?
No, it makes no difference.
Stephen
The pin hole for the timer roller is located to a relationship with the lobes on the cam. either way the gear is installed the cam will have the valves and the roller in the correct location to contact at the correct piston location.
Thinking on it, no difference on the later cams other than if the cam is 180 turned then when on TDC for #1 the marks would be 180 out, but if out 180 on an early shaft putting #4 at TDC and then put the timer on for a #1 start, because the pin in the early shafts can go in from both sides, confusing hey!! best to stick to marks lined up and at TDC #1
The wobbleometer says backlash is .007. I think I'm going to call that close enough for gummint work.
Kerry,
It's the cam that's 180 out. The crank is 360 out. It only makes the difference between #1 coming up on compression or exhaust. It doesn't know the difference.
True Hal,
But if you fit the cam to marks with out checking on cam, which # is on TDC firing, # 1 or 4 and with the option of the timer being able to be fitted 180 degrees apart on early cams, you have a 50/50 chance the engine wont run.
Later ones like Jim said are timed to the cam so all that could happen then is markings could end up 180 degrees out.
It still wouldn't matter. If you put it on 180 out and put the gears in mesh with marks lining up, you just turn the crank 360 degrees and the cam turns 180 and you are in exactly the same place you would have been if you had assembled it the other way.
Hal, for the cam yes, timer no, if doing the cam gear as Steve has shown, he shows the option of the cam being 2x 180 degrees for fitting, say you happened to pick the cam to be at the TDC firing for #4 and because we all work to set every thing using #1 as our starting point, fit the timer to fire on #1 without turning the crank 360 because the timer pin can go both sides of the cam, (hole go's right through on early cams)we have fire compression on #4 but timer spark at #1, engine wont run!
Kerry,
Of course you can get the timer rotor mis-located on the 2 hole style, but that's a separate issue and has nothing to do with the cam gear installation.
Jerry, it has a lot to do with the cam installation, you just can't stick it in and think that the timing marks lined up will give you an automatic #1 when you have the 2 options, and marry the timer to it without checking what piston is going to fire. this problem was solved in the later cam by only being able to fit the timer one way.
If that happens, simply turn your brush or roller or flapper 180 degrees. The relationship of the lobes to the timer brush pin hole is set when the cam is manufactured. Still has nothing to do with the relationship of the camshaft to the crank shaft. Take any 4 stroke engine and turn the cam gear 180 degrees (if you could. Most are keyed only one way). But drill another index hole or broach another keyway. Whatever it takes. And reinstall the cam gear/sprocket 180 degrees out and the engine will still run perfectly.
Hal, the question of cam to crank was not an issue other than to keep the timer right.
Line up the timing marks, put the cover plate on, don't worry about it. Crank by hand till you feel #1 on compression stroke, it'll fire #1 plug.
Only way to mess it up (not counting wiring done wrong) involves putting the timer flapper or roller on the wrong way on an early camshaft that has the pin hole drilled through.
I guess I'm lost. Steve's picture shows two ways to install the timing gear on the cam shaft. What I am saying is that either way will work as long as you line up the timing marks when you do it. If you cam shaft is drilled all the way through, there is still the possibility of installing the flapper 180 out which will make it fire 4 when 1 is supposed to be firing, but that will always be a possibility when using a cam that is drilled all the way through, no matter which way the gear is installed. If it's not drilled all the way through, it will simplify things and it will still run just fine no matter which of the two positions the gear was installed in.
Kerry,
You're confusing proper timer installation with cam gear installation. Steve asked if the gear can be installed either way. The answer is, yes, it doesn't matter, no matter which type of cam you've got.
If he asked how to install a timer with a "through hole" cam, then your advice is correct but still has nothing to do with how the cam gear went on.
Very simple. Line up the marks on the gears. Don't worry at this time about the timer. After you get the gears lined up and the nut tightened down, and the front cover on the engine, then is the time to line up the timer. If you have a hole only on one side of the camshaft, that's the way the brush or roller goes on. If the hole is drilled all the way through the camshaft, you will need to find top dead center compression stroke of #1 to line up the timer.
Norm
Jerry.
Some very simple rules apply if you have been taught your auto trade by the book
when dismantling an engine you check things that they are right, screwing the engine to TDC on #1 and checking valve timing is one, and put it back together the same way, then no mistakes, same as all bearing caps all back the same way as they are matched, all numbering to face the cam shaft, mains and big ends.
If done right in the first place you will avoid problems such as a 180 degree change on timing gears changes the wear pattern that's already on the teeth can result in noises you didn't have before, so the answer you post as yes is really no, as it is not mechanical practice.
Sorry not thinking, early morning, gear mesh wear still in the same pattern.
Gear can go either way! It doesn't make a difference!!
Ford installed the Gear on, Front Toe of the cam Opposite the cam timing mark, thats it. But it doesn't matter Kerry!! Read the Ford Service Bulletins. Sooo, If you have those very simple Rules that you have been taught your Auto trade by the Book, that one, you forgot to read.
The Ford Book says "Quote" The Gear may be assembled with the "O" mark either way with Relation to the First "CAM". If it matters, why not say it did. So if in your mind there is a difference, what is it that is Factual!!
I haven't a problem with which way the cam is fitted at all, just brought to steve's attention that of the timers.