Hercules IXA Camshaft Timing

Bill Copeland · Mar 3, 2009

Has anyone timed the camshast gear to the grankshast gear without using the marks? I just rebuilt a 1935 IXA and when i went to put it together i found three marks on the cam gear and two on the crankshaft. Both gears have an " S " marked on them but aglining them does not get me any compression. All cylinders passed the leakdown test by at least 90% So the new rings and valves are good.Do i just keep aglining different marks untill i get compression?

Dblair · Mar 3, 2009

compression stroke both valves are closed piston at top. intake stroke piston at top, intake just starting to open. exhaust stroke piston at bottom exhaust opening, closed at top intake starting to open . does this help? find top dead center . put an indicator on the piston top. bring piston near top to within a .100 . mark the balancer with scribe at pointer . reverse direction bring piston back to the same place on indicator, mark balancer with scribe. split the difference, that's the top dead center.

Hobo,NC · Mar 3, 2009

This has worked on every engine I have ever worked on. One cam 2 cams are four are any amount of cylinders. This is a reply I made to a Ford flat head so you would have to convert it to your engine

An old trick to see if valve timing is right on a flat head would be to remove the head or lifter cover and bring #1 cyl up to compression stroke. While you are rotating the engine coming up on #1 TDC, #4 should be on overlap (exhaust valve closing, intake valve opening). This should happen right on TDC #1. If a valve on #4 is wide open or doing nothing at all, the valve timing is off... weather it"s the cam gear . crank, gear or key way, broken cam,etc. The reason # 4 is the cyl in question is because that is the "middle" cyl in the firing order 1-2-4-3. The "middle Cly should always be in overlap. for instance, on a chevy the firing order is 1-8-4-3-6-5-7-2, so if we wanted to see if the valve timing was off we would look at cyl# 6 to see if it was on overlap rolling the engine over to #1 TDC. It should overlap right at #1 TDC at 0 degrees

John B. · Mar 3, 2009

1. Watch the #4 cylinder's ROCKER ARMS OR VALVES and when the exhaust valve almost closes and the intake just starts to crack open (this is called overlap)stop while in this position, then #1 valves are ready to fire. This will time your camshaft.

2. Next while in this position mark two of the CAMSHAFT GEAR teeth that are currently in mesh with the teeth on the crankshaft gear. Now that you have the camshaft teeth marked turn the crankshaft until the #1 PISTON is at TDC and mark one tooth on the crankshaft that is currently in mesh with the camshaft gear teeth.

3. Now just align your marks up and you should be good to go.

4. I've done this many a time on old engines with no marks. Especially the old one lungers-hit a miss engines. Usually multi cylinder engines have timing marks but not always.

RAB · Mar 3, 2009

The simple answer is it might work but......

The sensible way is to find TDC, as described below, and find the rotation point at which either an inlet or exhaust valve opens and check it out with a dial guage (or some other device). Easy to measure degrees - either a large circular disk and pointer, or measure around the flywheel and calculate appropriate distance, or use flywheel bolt spacing, if symetrical. Lots of ways to do it really. Just depends on what is to hand.
Overlap of valves is another possibility.

Getting close may indicate which lines to align.

Regards, RAB

Anonymous-0 · Mar 3, 2009

Its been o long time ,but i think only one of those marks is inline with the key that holds the cam gear inline. That mark is the one you match to the crank mark at tdc.

Hercules IXA Camshaft Timing

Bill Copeland

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Dblair

Well-known Member

Hobo,NC

Well-known Member

John B.

Well-known Member

RAB

Well-known Member

Anonymous-0

Well-known Member

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