Engine: NEW TIMING GEAR install advice needed for SPECIAL 6 , RE: piston valves , marks etc.

[Newstew25]

No markings on the new timing gear >>>> 1925 special 6 <<<<< any advice to the placement of my new timing gear ? Maybe by the keyslots ? can anybody tell me If my CRANK key is at 6 o'clock where should my CAM key be ? I did it manually according to the piston at TDC and exhaust valve ready to open but no luck I need a PRO to help this along

[altair]

I don't know any thing about a 1925 special 6, but if #1 is top dead center on the firing stroke, you should be on the back side of the cam lobes. With out the cam gear on, insert the distributor and turn the cam until the points are just about to break. The cam should be in the correct position, press it on just enough to engage and turn it over one revolution to confirm #1 firing at TDC and the exhaust and intake cam lobes are in the correct position ie the backs of the lobes are facing upwards. If you were out a cog on the gear the timing would also be off. It would help if you knew where the distributor was relative to #1 TDC. There is always a chance you could be out 180 if so, try both ways.

[jclary]

No markings on the new timing gear >>>> 1925 special 6 <<<<< any advice to the placement of my new timing gear ? Maybe by the keyslots ? can anybody tell me If my CRANK key is at 6 o'clock where should my CAM key be ? I did it manually according to the piston at TDC and exhaust valve ready to open but no luck I need a PRO to help this along

Welcome to our forum! None of my Studes are as old as yours, so I will not attempt to advise (mislead) you. However, unless you are in the witness protection program, how 'bout going to your forum settings and adding your location. Could be that there is some knowledgeable person, living near you, that could offer friendship and help. There are mechanic's shop manuals that are available for our vehicles going back (at least) to the 1930's. I don't know about 1925, but if they exist, you should make the effort to purchase one. Our vendors offer them in CD and reprint versions. In addition to the Studebaker Drivers Club, there is also an Antique Studebaker Club, (covering pre-war vehicles). You can access them by going to the main SDC website. Hopefully, one of their members will see your post here and give you the link. Best wishes with your engine.

[gordr]

Does this use a timing chain, or is it direct gear drive? In the latter case, there should be punch marks on the gears to guide you. Marking schemes for chain sprockets vary. If the timing is right, at TDC on the exhaust stroke, the two valves should "rock" as the crank is move forward and back. Meaning, as the exhaust valve closes, the intake will open. At TDC, it's common for both valves to be open a tiny amount. You should be able to find a spec for valve timing for that engine, and how to measure it. Normally it means setting your valves to a special clearance for measuring purposes, putting a degree wheel on the crank, and using a dial indicator to determine first/last motion of the valve being checked.

[altair]

When starting the power stroke (ignition) both valves are closed and remain until the piston is at BDC and starting up on the exhaust stroke, at that time the exhaust valve just starts to open. As the piston returns to TDC the intake valve just starts to open and the exhaust valve is fully closed to emit the fuel charge on the down stroke, as it returns to TDC again it is now on the power stroke again. I would like to confirm that your cam is gear driven and there are no timing marks. The timing mark should be there on the outside only it may be difficult to see. I just installed a cam gear on my 259 and the timing mark was very difficult to see but it was there. I highlighted it with a paint pen.