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Distributor hitting rad hose
My 1973 Grandé looks to have the stock distributor with the points removed and electronic added.
My problem is that when I want to turn it clockwise to advance the distributor the vacuum diaphragm hits the rad return hose?
So I can only get about 4 degrees atdc?
The engine is a 351c. Was a 2 v and now has edelbrock 4v intake a carb.
Any help would be appreciated.
possibly installed 1 tooth off??


1971 Mach 1
408C Stroker
C4 w/3,000 stall
8.8" Rear w/3.73's
Disc brakes all way around.

[Image: 28ivsix.png]

it is a common issue, you either hit the vacuum advance on the rad hose or the a/c compressor due to clearance.
what has to be done is the distributor needs to be pulled and indexed one tooth opposite to the direction you need to move the advance to obtain the timing you want.

it isn't hard to do but it can be frustrating. the distributor can be stuck, the oil pump pick up can move around at the bottom of the shaft and make it VERY hard to push the distributor back into the block with correct gear alignment. you may need to bump start the motor to get the distributor to seat.

i had to do this on my car and it took a couple of tries to get it right, sometimes it can jump 2 or more teeth when you thought you got 1 tooth.

if you are not comfortable with doing this a mechanic should be able to do it pretty fast,

as a run down.
* turn over the engine so #1 is on the compression stroke, you have to pull the plug and feel with your finger you want air to blow out and the pistion around TDC so you can make sure your rotor is aligned to #1 on the cap.
* loosen distributor bolt,
* remove the holding plate under the distributor base.
* mark #1 on the distributor base using the Cap as reference, you will need to hold the rotor on that mark when you reinstall.
* pull distributor up, try keeping the mark aligned with the rotor center. you don't have to pull it completely out of the engine, but up enough so you can move the gear on the end of the distributor shaft.
* rotate the distributor to center the vacuum advance between your 2 end points(Hose or A/c compressor) so you have a range of movement for the timing adjustment.
* push it back into the motor with 1-2 teeth of difference as needed for the clearance.
* at this point the distributor might not go back into the block this is because the oil shaft isn't aligned.

option one, you fight with it for hours hoping god will hear your cries or you get lucky and it pops in.

option two, you have to pull the distributor out and use a REALLY long socket extension (pray it doesn't fall into the engine or you may need to pull the engine out to get your socket back) and move the oil shaft just enough so the distibutor catches it and it pops in.

option three, bump start the motor, you can use a remote starter and the bump start will move the engine slightly and pull the distributor down into the block
problem: either it works or you can cause the oil pump shaft to snap or the pump shaft could pop or break and fall into the oil pan, and the engine needs to come out to make repairs.

now i've used the bump start method a couple of times without a problem and one time i even got lucky and the distributor went in on the first try.

this is why you may want to have a mechanic do the job if you feel uncomfortable.

* once the distributor is installed then make sure you have seated it and the rotor is aligned with the mark for #1(and your not 180 degrees out opps that can happen if you are not careful.usually this happens because on the first step the engine was not on the compression stroke at TDC for the Power stroke to start.)
* then put the distributor plate back in but do not lock it down.

* setup your timing light and start the engine once running then set your timing and lock it down.

again it isn't a hard job its one bolt but it can be frustrating.

you can read more here
'Code's method is right on. Another concern is if the washer is missing on the oil pump shaft or it was installed wrong end up the shaft can pull up with the distributor and then fall down out of the pump.

One more way to rotate the engine is to use a socket and breaker bar on the crankshaft, may require removing the spark plugs before and after #1,in the firing order.

“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
Another possible method is to move the spark plug wires over one position and re-adjust your dizzy to the new #1 spark plug wire position. This method assumes you have enough adjustment of the distributor of 360*/8 or 45*. If not, please ignore.

Let me check your shorts!

[Image: Flamicon2.jpg]

[Image: oldfart.png]
+1 for Midlife. I think we have been there before. Rotate them wires and find that happy spot. The repositioning works great too. But considering the risk and the fact I want to drive it Saturday, I'd move the wires.
Thanks, I really appreciate the wise feedback.
I did try to move the plugs over one position. Fist counter clockwise and I couldn't get it to fire. Then clockwise and it fired right up, at its movement limit the other way (wire terminal hitting the intake manifold). At that point it was 32* btdc and moving it clockwise increased it ?
Did I miss something?
Another suggestion is rotate the motor with a breaker bar until the rotor is pointing at #1 plug wire on the cap. You are now at compression stroke for that Cylinder. I am assuming that the motor was running ok previously. Remove the bolt from distributor base and then make the 1 or 2 tooth adjustment. When this is done rotate the distributor body until the rotor lines up with the #1 plug wire on the cap again and you are set. You don't have to remove the plug and feel for compression if you do it this way. Remember 2 revolutions of the crank to 1 revolution of the rotor. If you have the oil pump priming tool you can use that to rotate the oil shaft so that it aligns with the dizzy shaft. If you are lucky it just slips back in. Hope this helps.

351C 4V cc heads, 10.5 : 1 CR, 290 Herbert cam, Flat top forged pistons, forged connecting rods, Atomic efi,
C6 with Gear Vendor overdrive, 3.89 Tru Trac, Hooker Super Comp with 2 1/2" Pypes Exhaust.        

Some Mod pictures can be seen at:

You would move the wires clockwise one hole. Then rotate the distributor counterclockwise until it lines up with the original wire. You will spin ccw it about 3/4".
Well, that didn't work out so well...
I move the wires over one spot, unfortunately I didn't warm the car up first, and couldn't get it to start. I tried moving the distributor to so many positions, but nothing. Then I put it back the way it was and haven't been able to start it for days. First I thought I had extremely flooded it because every time I take the plugs out most of them are wet. I have had fuel shooting out of the carb, slow cranking and other signs of the timing being off. But I'm sure I have it back the way it was. Now I'm starting to think I cooked the pretronix ignition? I had the ballistic resistor on the side of the distributor off? Maybe I buggered it? Help
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