cam gear timing 1936 LB engine

[FRANK PKNY]

I'm working on a 1936 lb engine that was rebuilt and sold to my customer. I think the cam gear is out of time, after installing the engine in a test stand while cranking over I'm getting compressed air out of the intake manifold and vacuum in the cylinders. Is it possible to change the cam timing without pulling the entire cam, by removing the cam gear and reinstalling the fiber gear? If so how do you remove the fiber cam gear?

 

[KiWinUS]

Pressed on or bolted.

 

[alanwoodieman]

you can change the timing, even the pressed on cam gear, even easier if this is a bolt on one. I saw a couple of guys change out a pressed on cam gear that had stripped teeth while still in the car and not removing the cam. kind of scary to me with them beating it on so to speak!

 

[Brian]

press on gear; I once encountered a 'slipped' cam gear...To fix it in place I aligned the timing marks; crank and cam gears, and made up a shaft with a tang on the end of it [to duplicate the tang on the distributor] I inserted the tang into the slot on end of camshaft and rotated camshaft until its timing mark aligned with that on the gear. [Remove sparkplugs first to enable this...] Then, to prevent the gear from ever slipping again, I drill and tap a couple of 'scotch keys'. These are simply grub screws fitting exactly on the seam of camshaft snout and camgear, which prevent any subsequent movement between the two.
Actually, I now install scotch keys in ALL camshafts with press on gears [which I use exclusively- steel 32 cams], in every engine I build.

 

[Brian]

Photo showing a scotch key

 

[FRANK PKNY]

pressed on , how do you pull off the fiber gear ?

 

[FRANK PKNY]

At TDC the intake valve is open indicating to me the cam gear is not in time. The crankshaft gear has no dimple on it I wonder if it's installed backwards? I thought all crankshaft gears had a factory mark on them. The builder put his own marks on with a marker pen , I believe he miss calculated the cam to crank position. I do see a factory mark on the fiber cam gear which at present is way off from TDC in the crank gear. is it possible to put
the crank gear on backwards?

 

[FRANK PKNY]

pressed on, wondering if I can pull it off and install it after I correctly line up the crank and cam?

 

[Bill OH]

I would pull the heads, valves, lifters and the cam, then install a bolt on gear and cam, valves and heads. Inconvenient - yes, but if the gear strips in the future, not to difficult to replace. Assuming your customer will agree with expense.

 

[Brian]

Because the crank gear has a chamfer on the back face to clear the radius on the crank snout, it's a bit hard to install backwards [won't seat correctly].

 

[Brian]

Is the mark on the camshaft in line with the mark on the camgear? Check that...I still reckon the gear has slipped on the cam [not enough interference in the press fit]. The mark on the camshaft is hard to see...if you look at my picture above it'll give you an indication as to where it should be [The pictured cam was degreed in, then locked into place with scotch key]

 

[Frank Miller]

If you can see the key you can look at another gear and see where the dimple is in relation to the crank key. Mark that tooth. Turn the engine until the cam timing mark is where you want it. Then remove the cam gear and bring the crank into alignment. Noow you can replace the cam gear. The pressing part I'm not familiar with.

 

[deuce5wndw]

If the cam gear is pressed on the cam correctly and they are just meshed wrong it would be easier to pull the crank gear with a puller then line them up and put the gear back on.

 

[alanwoodieman]

as far as removing press on cam gear, I would guess you could remove the fiber part and then drill/tap bolt hub for a puller?? just exercising what ifff:s

 

[Biggles]

The timing mark on the crankshaft gear may be hidden by the oil slinger.
If it is still not visible, this should work:
Turn the engine over until the camshaft timing mark is vertically down.
This is the camshaft position for top centre on #1 firing stroke.
Remove the crankshaft gear.
Turn the engine over until top centre on #1 (compression test).
Refit the crankshaft gear.

Good luck.

 

[Bob C]

At TDC the intake valve is open indicating to me the cam gear is not in time. The crankshaft gear has no dimple on it I wonder if it's installed backwards? I thought all crankshaft gears had a factory mark on them. The builder put his own marks on with a marker pen , I believe he miss calculated the cam to crank position. I do see a factory mark on the fiber cam gear which at present is way off from TDC in the crank gear. is it possible to put
the crank gear on backwards?

Check out the thread in this link. If the crank gear is on backwards
the valve timing will be off, see the picture on page 7 post 132.
https://www.fordbarn.com/forum/showthread.php?t=235272&highlight=crank+gear

 

[alanwoodieman]

two different cam drives were offered, so if you wanted to mate the wrong gears you would flip over the crank gear to get the teeth to align, with my fuzzy sometimes memory this may be the problem

 

[FRANK PKNY]

UPDATE I made a templet from a circle drill, that had three holes at the perfect spacing to mark and drill and tap the cam gear then used 1/2 13 bolts to go through the gear and push against the block.to remove the cam gear. got TDC on the crank gear marked with a paint marker as well as marked the timing marks on the cam and gear. Then simply correctly lined up the marks ( a tad difficult because of the crank pully being in the way) used a small mirror. put everything back together and test ran, without any problem. Photos show the story. Made three plugs from a 1/2 13 carriage bolt, slotted for a screw driver slot and set them with Lock Tight. total time 3.5 hours, took a video of it running is I can figure out how to do it. Thanks for the help Guys.

 

[FRANK PKNY]

Used a vacuum to grab the chips and also used paper towels to keep chips out of engine, a paint marker works great for marking drill holes and timing marks. keeping the holes close to the inside edge of the gear you actually are not drilling much fiber because the fiber is cast onto a metal insert. so after drilling and tapping I don't think the structural integrity is affected.

https://youtu.be/vuFAypO4G4U

Try the YouTube link

 

[Brian]

Well done Frank
Not trying to be negative, but I can now assume camshaft was installed incorrectly by the engine builder. If he[she] got that wrong, what else is wrong with this engine??