Distributor vacuum advance hitting intake.......

It might be worth while to pull #1 plug, rotate the crank to a point just before TDC on the compression stroke which would bring the timing mark up near the tab @ 0 back it off a little and check piston position with something you can hold in place as a piston stop. Then mark the damper wheel and rotate the engine around until the piston contacts the stop again, mark the damper again and see if the original timing mark lines up @ 0 while the pistion is at TDC on the comp stroke for sure. See if the damper outer ring has slipped. If so than you will never get the engine to time right by using the timing marks. In this case you need to replace the damper before it completely fails. If the engine is an internally balance engine it isn't such a big problem but an external balance is a problem. Once you are certain there is no problem with the damper alignment then set the rotor and housing in a place than allows you adequate movement to time the distributor correctly set the #1 tower usually pointing toward #1 but not always. It was said it doesn't matter as long as the towers and wires get the spark to the right cyl. at the right time. Next is the issue of rotor alignment to cap which is partly adjusted by the advance link in the diaphram. I have seen many distributors that would place the rotor part way between towers which causes a big loss in power if the rotor is pulling away from the correct tower as the timing is advanced by the diaphram. It causes the required voltage to fire the plug to increase excessively when under load the reserve voltage the coil is capable of making is having to jump longer gaps in the cap instead of being left to jump the plug gap under high pressure which always goes up. There are 2 ways to see this, one is on the screen of an engine scope and the other is to look at the burning on the rotor and tower conductors, you have to be able to relate rotation to direction of the movement of these 2 pieces. if there is a problem here you can bend the link arm to move the pickup coil or points plate to get a better alignment. The other thing is a jumped timing chain, I had a 318 that was only 1 tooth off and it ran OK but ran better when I advanced the distributor a little which put the timing mark way off. It ran Ok because the chain was so stretched it was not all that for off when it was running but when I tried to set the timing where it should have been it ran like crap, so when I got to run Ok at idle with the advance connected and reved up the engine it would backfire and stall out until the rpm dropped down a little then take off again and backfire at the high end. Quick fix was to disconnect the vacuum and advance static timing until I could afford a new chain and gear set and had time to fix it. Some wire sets are hard to get to fit up when you put #1 towards #1 cyl which is why factory puts #1 somewhere else and marks the cap for #1 where ever.

gtgto said

Tried to reset my timing over the weekend. Found the vacuum advance hose was split cause its binding on the intake where the timing was set. After removing the cap I turned engine by hand to get rotor pointing to 1 on distributor and engine to TDC. I figured I would rotate the drive gear for the distributor a tooth or two clockwise which would essentially created the space I need for the vaccum hose to not bind on the intake. After doing this and re inserting the distributor the rotor was not far off from where it originally was pointing. I only moved it a tooth clockwise. Should I now move the plug wires one post clockwise? The rotor seemed to be pointing similarly to where it was originally but I have much more clearance for the VA hose. The rotor seemed to be in between posts on the cap. This is so basic yet a problem for my brain to comprehend. The car seems to be running fine but the timing mark seems to not be where it should be. I started getting annoyed and had to stop but I am planning on getting under the hood when I get home today.

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ght be