When you put in distributor. Which way should the rotor face? Some books say facing strait ahead. Some books say pointing at the number "one" cylinder. And I've even heard that you put the rotor under the number "one" plug port on the cap. So, which is the CORRECT Corvette way? I need it to be exactly at zero. I don't want any advance on the motor. Now while breaking in the cam.

Aaron

 

You want it pointing about half-way between forward and left. It should be under the #1 plug wire. Point the oil pump at the #5 cylinder.

 

Sweet.

Is there anyway (degree or whatever) the dist. should be facing when I fire her for the 1st time?
I need the timing as close as possible when I fire it so I can get the motor up to 2,000rpm.

Or do I have long enough to set the timing and all that before I pull it up to 2,000rpm??

Thanks for all the help. I know I SHOULD know this by now..but this is my 1st virgin fire up..

Aaron


[Modified by Aaron-74, 7:18 PM 4/15/2002]

 

This is always the most fun. I'm not sure if you can accurately time it so it will start right off the bat. I had to twist mine stop to stop before she would start, I was getting worried. As long as you've primed the oil pump, a little cranking isn't going to hurt anything.

Hopefully somebody can chime in with a way to get within a few degrees so she starts a little quicker.

 

Oh yeah, BTW, the distributor spins half as fast as the engine, so it fires once for every two rotations of the engine. It could be on the non-fire stroke. Do you still have a valve cover off to look at either #1 or #6 valves?

 

More important then rotor placement is distributor housing placement for proper oiling. If you’re not sure of this then contact Lars. I believe he has pictures available.

 

Is there an indicated position on the cap that has #1 marked on it? I don't recall ever seeing one.

It really doesn't matter. Wherever the rotor points to when the #1 cyl is at TDC with both valves closed, you want the spark plug wire for #1 right over wherever the rotor is turning.

Interesting.....

I just looked in the Haynes manual. For cars with points, they show the #1 position on the cap/rotor to be when the rotor is pointing toward the RIGHT front of the engine (so toward the #2 cyl) and for HEI cars, it's pointing toward the #1 cylinder. That's goofy. But shoot for either of those and you'll be pretty normal.

You'll have to set the timing no matter what. It's next toi impossible to get it set to any particular spot (zero included) when you trop the dist in.

Good Luck!
Dave

(Hey Canyon, Jenny hasn't posted here. Are you expecting her to? :p: )

 

There's a Paper on http://www.corvettefaq.com by Lars for putting in a Dist and setting advanced timing. I used it when my dist got off. The Rotor and the accompanying number 1 cylinder should be pointing at approx the 7-8 oclock where 12 would be the center of the firewall and 6 would be facing the center of front. It doesn't matter for your car to run (just needs to be under the number 1 on the cap)...but that placement above is correct according to Lars...and also where mine needed to be, to hook up the tach drive...which I guess you don't have to worry about if you're hei.

 

The rotor should be aligned with the mark you made on the housing BEFORE you removed it and the housing should be aligned with the mark you made on the manifold or firewall BEFORE you removed it. When doing it that way, you don't have to guess about the position of the dist as you reinstall it and your timing should be very close to where it was before you started. If the camshaft position has been changed (or you didn't mark the distributor and rotor before removal) you'll need to start from scatch. After making sure that the #1 piston is near tdc of the compression stroke (both valves will be closed) align the timing marks at the appropriate initial setting (8º, 10º, whatever) and align the rotor with the #1 position of the cap. Don't set your timing to 0 as it won't run worth crap.

 

Here we go...

When the motor was still running in the car. I used the timing light to degree it with the timing marker connected to the timing chain cover. Well, when I pulled my motor apart I noticed that TDC on the timing marker connected to the cover wasnt TDC because the piston had already started moving down. I looked at the timing chain cover and there was a little tab in the center welded on..so I turned the motor over to zero and sure enough that was TDC ( I wasn't able to see it due to the water pump) so..my motor was running too far retarded to begin with.

I'll just be sure to get it timed real quick when it's started.

The rings, bearings, rods and pistons are all stock and not removed from the motor. But. EVERYTHING else is new..or completely rebuilt.

 

why when you have done this much work didn't you replace rod and main bearings?With engine that much apart it wouldn't have been much trouble to remove the block.

 

Aaron,
I'm doing the same thing ie. putting the dist back in with a new cam fitted. I've got some pictures I took of the rotor & body that I took with no 1 at TDC (according to the pointer on the timing cover). I'm hoping that lining it all up as it was will give me base timing of 6 deg. If you want I can email you the pics tomorrow ('81 with HEI).
Also noticed that bit in the Haynes manual regarding the no 1 lead on dist cap. It looked to me like the no 1 lead if non HEI was the p. side contact at the front & was the d. side contact if HEI. Reading that is what made me take the pictures :)
:cheers:

 

When I stabbed my distributor two weekends ago after a top-end rebuild, it took me three tries to get it in, but then it was timed almost dead on with my 12 degrees of advance already dialed in. (The first time I stabbed a distributor, 6 months ago, it took 5 hours...)

So, here's how I did it. Make sure that your engine is TDC Compression stroke on the #1 cylinder. (Both valves should be fully closed) Once there, move the oil pump drive shaft so that it points at the #5 intake pushrod. Line up the distributor gear (pointing at same pushrod) and slowly lower it in. It may take a little wiggling and finessing, but it should slide right in. For almost no advance, you want the vacuum housing pointing roughly at #4/#6 cylinder.

Make sense?

 

If you plan to install stock ignition shielding, you need to check your AIM to see where (in the distributor cap) #1 wire needs to be. If you don't have everything oriented correctly, when you set the timing, the vacuum advance mechanism will not fall in the correct location (or hit the firewall) and you will not be able to install the shielding box.

 

Perfect...sweet


I don't have any ignition sheilding.

 

If you have the points distributor then it's no problem lining up the rotor properly. Keep in mind that the distributor body must be installed in the correct direction as the others pointed out. The distributor must be twisted slightly as it is installed due to the gear meshing with the camshaft.

Also, if you look down inside the hole where the distributor goes there's a slot...which is where the distributor shaft turns the oil pump...you need to use a long screwdriver to turn the oil pump so that the slot lines up with where the distributor begins to turn as you slide it in.

What I do is pull a valve cover and put a socket and ratchet on the crankshaft and turn it until I can watch the intake valve open then close...then I line up the crankshaft with the TDC mark to be sure it's at TDC and ready to fire on #1. I then install the distributor...at this point the rotor is pointing near to firing the #1 cylinder so I check the cap to be sure that the #1 wire is in the right place. Now with HEI ignition that's all I can do...I stick the rotor on and install the cap and fire it up.

With points you can get it tweaked better by keeping the distributor a bit loose (you will anyway so you can adjust the timing when starting it) and moving the distributor until I can see the points start to open...then I back it off just a hair so that it's BTC and guess at how much depending on the timing specs. I've had several engines where I didn't have to change the timing cause I got it dead on during install.

 

Few words of caution: You don't want to set the approximate timing too retarded or else the exhaust temps go up during the cam break-in. I've HEARD stories about glowing exhaust manifolds or burning exhaust valves while doing this. Try to shoot for approx 10 deg advance and watch your engine temp gauge closely while you are breaking in the cam. Good luck!