chevy 350 distributer won't drop in

we are having trouble with the distributer on a stock 350 with the distributer not wanting to drop all the way in and engage oil pump and gear. We have had the thing top dead center, jiggled and wiggled and no luck. This is a hei unit, any clues would be appreciated, this has never happened to us before. ~sololobo~

 

do you have the correct oil pump driveshaft? is it seated on the oil pump properly?

 

If it will go in almost all the way lacking maybe a 1/4 inch, the oil pump shaft needs to turn. You can bump the motor and it should drop in IF its just the oil pump shaft alignment with the distributor.

 

tried bumping it in by turning over, but won't go down. This is a bit of a mystery motor bought from a friend who bought it from a friend, so I don't know if the oil pump drive is different. I also don't know if it was an hei or a points distributer before but my experienced helpers say they are all the same. ~sololobo~

 

x 2

 

make sure its not a pontiac hei Unit as the gear teeth are reversed .. had a few new cheap units misboxed .( Ahh dat wook das same so in DAh bahx it go...)

 

Chevrolet distributors all drive the pump the same way. Sometimes you can have the dist gear engaged on the cam, but the pump shaft not in alignment with the distributor shaft. how much is it lacking from dropping in?

 

After the distributor hits bottom when installing have you tried turning the rotor 45 degrees either direction to get it to slide in? That usually does it and then maybe turn the motor over to get the oil pump drive to fit for the last 1/4"

 

Set your crank at either #1 TDC or #1 8* BTDC. Look down the hole for the distibutor. Take a big long flat screwdriver turn the oil pump shaft till its groove points toward #1 cylinder. Take the distributor place it in the hole, turn the rotor pointer towards #7 (or 90* to the centerline of the block). Slowly lower the distributor down when it touches the cam gear, allow the rotor to turn clockwise as you let the distributor fall down into the hole. The rotor pointer should end up pointing at #1 now as well.....the key that drives the oil pump is in line with the distributor pointer. Just did this 2 minutes ago.

 

Once you have it lined up for TDC, and the rotor lined up, just stab it in. Then while someone is holding the distributor in place, some one else can just crank the engine over until it drops onto the oil pump shaft. You don't have to fool with trying to line up the shaft, or do any mirror ticks to see in the intake to move it.

 

I have had a couple that wouldn't drop on their own, and just needed a gentle push while a friend cranked to get it to drop.

 

Going back at it this afternoon, will report in later on progress. All the kind help is appreciated. ~sololobo~

 

There was a similar deal over on the trifive website. The poster was was using an MSD "ready to run" dist. , turned out the problem was the car was sitting on a steep inclined driveway and the pump drive kept flopping to the rear preventing the dist from dropping down or at least that's what he said .

 

Did this engine by chance have a chevy 2 oil pan on it ? If it is a chevy 2 oil pump with a reguler chevy oil pump drive rod it will be to long.

 

oil on gear? and pour some in...this may help, sometimes they can get hung up as you describe

 

As you drop the distributor into the block, carefully watch the position of the rotor. The distributor gear will start to engage the cam gear, and as it drops further into the block the rotor will turn slightly clockwise, due to the distributor gear having spiral cut teeth.

Wherever you want the rotor to point when everything is fully installed, it will be necessary to set the distrubutor into the block starting with the rotor advanced about one tooth ahead of its desired final position. But as you've discovered it won't usually drop all the way in on the first try because the oil pump drive shaft isn't aligned perfectly.

As already mentioned, quickly bumping the starter a time or two will usually get the oil pump drive shaft to align and let the distributor drop in fully. And the rotor may then look like it's now in the wrong position. But as long as you haven't lifted the distributor up far enough to disengage its gear from the cam gear it will be properly phased. That's****uming that you did properly start with the engine at TDC for #1 cyl on the compression stroke.

 

Saw a similar post on here recently along the same lines. OP had the same problem and it ended up being that the tang on the end of the distributor shaft that engages the oil pump was twisted almost to the breaking point. It was hidden up inside the gear so it was hard to see.

 

Make sure the distributor gear is not on upside down. I have seen this happen it will not go in. Someone had replaced the pickup coil and installed the gear the wrong way.

 

well that goofy deal is over, a intake manifold bolt had gone down the distributer hole. Thanx for all the great idea sharing. It was so friggin frustrating for such a normally simple task. Five of the brother hood were there takin stabs at the dizzy, Then the master wrench Terry called foul, So better lighting and eagle eye Rob Lee spied the little******** and we were set free. Onward! S.O.T. brothers rock ~sololobo~

 

Just To be sure the shaft is not sticking up too much, install the distributer with no gasket and the base should hit the manifold

Then with the gasket in place you know the oilpump shaft will not be bottoming out in the pump

Good thing to do on each new engine you work on to know it is correct

G Don

 

You very lucky the dist. Would not go in!

 

Make you wonder what else is down there.

 

I had the same problem on a 350 with an old edelbrock manifold. It turned out the bottom of the larger dist was hitting on the intake runner of the manifold.

 

Larry..how da hell did a manifold bolt get down the distributor hole? Good thing Rob found it before the distributor gear ate it.
"SOT brothers"??? South Omaha Truck brothers? I know almost all the south O boys have matching blue 60s chevy pickups except for Terry B's primered 68 shortbox. Is that what the "SOT" stands for?

 

Listen to this man he got it right,how do I know,i`ve only been doing it for 45 or more years.

 

When all else fails, get a light and look down the hole. Why didn't any of us think of that yesterday? Good to see that you got it squared away and a good reason not to set the intake bolts on top of the intake while you are removing or installing them.

 

Had the same problem in a 283 I rebuilt. Somehow I had used the shaft from a 409. Appears they are 1/4 inch or so longer

 

Glad you found that bolt !!!!!!!

4TTRUK

 

whoo good catch

 

Always interesting to see how many don't read the thread before replying. Bore cameras are fairly cheap [$150] compared to the cost of repairs and some parts stores loan or rent them. I wonder how I ever got along without one.