I'm trying to find TDC on my 85 F150 with 300-6. The Pulley/Balancer has two marks on it and I don't know which one is correct. One is a scratch mark and seems to correspond with valves and compression test. The other is a notch, but seems to be 90 degrees out. I have lined up what I thought was TDC, but the truck won't run. Which timing mark is correct, and are there any other tricks to lining up an EFC distributor?

 

Not to worry my friend! I struggled with this issue on my '85 I6 also!

You will have to clean off the harmonic balancer with a piece of sand paper and/or brake cleaner until you find the TDC line stamped on the balencer. It seems small and insugnifcant but thats it. Mark the line with paint or white out. Ignore the notch! I understand it could be used for a crank position sensor.


The engine timing marks are on the PASENGER side of the timing cover. Along with a series of fine little "teeth". Again hit that baby with the brake cleaner and a rag to scrub off the crud. You might even find an old paint mark at 10 degrees BTDC. (I did on my truck!).

Hook up your light and have your buddy turn the distrib while you watch the timing marks.

Good luck, DEAN

 

Thanks for the help! I actually got it running without the timing mark, but I still want to dial it in more accuratley. I pulled the #1 spark plug and dropped a long screwdriver into the cylinder. I then cranked the engine until the screwdriver stopped being pushed up, then re-ordered the spark plug wires with #1 over the rotor. I figured if it wasn't on it would be 180 out and an easy fix. I turned the key and she fired right up. I advanced the timing by feel and its running strong again. Thanks again for the help!

 

JMC302, 300 balancers are known to slip. The mark on the pulley you found probably slipped 90 degrees out. You can either make a new mark, or, I think there's a way to time an engine with a vacuum gauge.
Edwin

 

Please tell me how to time with a vacume gauge. Hi or low vacume? That would be a huge help as I've been driving the truck and finding true TDC to mark is next to impossible without pulling the motor open.

 

Don't time with a vaccuum gauge, you'll always be too advanced. it's the best way to set a carb, but i'd rather time by ear than with a vacuum gauge.

As for your problem, 300-6's can actually have *two* timing marks. My balancer has two notches in it, not filed in but factory. One lines up with the TDC mark on the pointer on the passengers side of the block while the other notch lines up with the timing mark cast into the timing cover. They both line up at the same time, just 90* out from one another.

Justin

 

I was doing the timing on my 85 300 on friday and dioes this mean that the "fine teeth" should line up with the notch? Then the smaller mark lines up with the notches on the timing cover? I can not find any marking on the fine teeth on the passenger side, I set it in the middle of the notches and it still seems slightly advanced. Any suggestions?

 

the fine teeth on the passengers side have numbers on them, but they're typically pretty hard to see due to paint/grease/grime/whatever. I don't recall which of those is TDC since I typically time mine using the marks on the timing cover since they are defined ALOT better (but again, which timing pointer you use depends on where the timing mark on your pulley is).

IIRC the second mark from the right is TDC on the fine teeth and the last mark on the left is 16* advanced.

Justin

 

hoxiii, I was reading one of your past post on the timing marks for the 300 I6. Mine is rusted and the numbers gone and was looking for some indication off the teeth for TDC and 10 BTDC. When you say marks in your post do you mean the teeth? and the peaks or the valleys. Thanks. ethan