Are these any help?
1830 r-688 timing marks
Can anyone tell me where the ignition timing marks are on the continental/Renault r-688 (4cyl gas) engine? I'm trying to time it with a timing gun but cant locate a mark on the front of the engine. Thankswww.skidsteerforum.com
View attachment 33043I noticed that when number one and number four are top dead center that the notches in the pulley align with this roll pin. Seems like really a coincidence but may be. Also, is number one on the flywheel end or the crankshaft pulley end?
I have the manual in the link. It shows a pointer about 90° counterclockwise from the roll pin. There is something in that position that might be a pointer, but it doesn’t align with top dead center.
So which plug is the #1? is it next to the flywheel or next to the crankshaft pulley? Note that we’ve had the distributor loose and trying to make this run so we can’t depend on that for precise alignment.Remember that the engine makes two complete turns for each power stroke, so the timing marks line up twice during each complete cycle, so you need to confirm you have cylinder number ONE at T.D.C., not cylinder four. The easiest way is to remove the top of the distributor and check to which terminal the rotor arm is pointing. If it's pointing to the H.T. lead connecting to No ONE plug, you're right on target!