Distributor won't sit down all the way on my 327

[chewychevy67]

So I'm getting to the final parts of my engine before I can run it. Sat my distributer in last night (tried 2 different ones) and it won't sit doen all the way. It's about 1/8" or 0.010 from the intake. It is down into the cam gear as it should be but must be bottoming out on the oil pump shaft. Block wasn't decked but the heads were shaved. All gm parts here. Is this common after machining heads ? Anyone have a good procedure for shimming and making sure the gears mesh properly? Melling oil pump and shaft.

[kwmech]

Is the pan on already? I'd say pull the oil pump with the dizzy in and see if it drops. Missing gasket, but that is still not right. Oil pump drive shaft too long? Where was the dist sourced from?

[truckster]

Are you sure it's aligned with the oil pump shaft? Use a long screwdriver to turn the shaft a little bit at a time and try to stab the distributor back in.

[chewychevy67]

The pan is on but no oil in it yet so I can remove it if I have to. It's a original gm distributor I restored.

[chewychevy67]

It is aligned with the shaft. I have moved the shaft with a screwdriver. It doesn't Chang anything

[kwmech]

Dist drive gear installed correctly? We've seen that a time or 2 here. Plus the dot on the gear lines up with the direction the rotor points

[68c10owner]

Depending on how much the heads were shaved it COULD cause a issue but if that much was taken off the heads then the intake manifold wouldnt fit right either unless that was machined as well. there are a couple different thickness distributor gaskets if I remember right.

[The Rocknrod]

Do we know for sure that the tach drive distributor is made to go on that intake? Didn't Corvette use those distributors? I'm asking cause I don't know for sure.

[chewychevy67]

I don't know for sure but I haven't seen any when I was purchasing them listed for special applications. I could see Maby if it was half inch out or something but this is so small.

[kwmech]

Pull the dizzy out and let's see the bottom of it

[toolboxchev]

This here will get it solved.

https://www.crankshaftcoalition.com/...EI_distributor

Even though your not using an HEI???

Shims, my good man! By the way, excellent looking build. Use this motor oil on break in with comp cams break in ZDDP

https://www.valvoline.com/our-produc...vr1-racing-oil

[chewychevy67]

I'll look a little more int this tomorrow

[chewychevy67]

I've tried everything but removing the pan. Pictures of the distributor.

[Mike C]

Moroso makes a nylon shim set to space the body up to keep from preloading the oil pump gears and ruining the pump.

[kaycee]

So wheres the paper/felt gasket ? Double up the gasket and try it, did you try a non tach drive dist and see if it falls correctly?

[chewychevy67]

I have tried 2 regular hei distributors and they sit exactly the same. I'm thinking Mabey there is an issue with the way the rod is sitting in the oil pump. If I turn it with a screwdriver it turns freely and is not binding though. I hate doubling up any gasket. I'll take the pan off again to investigate further in the coming days when I have time and report back.

[kaycee]

DId you use that plastic collar that holds the oil pump shaft on the pump , I wonder if it is not quiet down on the pump .Take a long scew driver and set it on the shaft and give it a love tap . worth a shot. Best bet is to R&R your pan.

[chewychevy67]

No plastic collar. It has the shaft with the metal collar that came with the pump.

[garyd1961]

Are you sure you are lining the slot in the oil pump shaft up with the cross pin in the gear?
The gear rotates as the distributor sits down into the intake and you have to back up the gear to allow for this rotation.
It may take several tries to get it right.

[chewychevy67]

I have been trying on my free time continuously for a week. I will keep trying but I am feeling like something else is the culprit.

[geezer#99]

Pull the gear off and chamfer the end of the centre post with a fine file. Sometimes a slight burr can keep the tang from sliding into the pump clip.

[kwmech]

At this point I'd pull the pan off. Remove the oil pump, install the dist and see if it seats down. Then do the opposite, install the dist and shove the pump up and see how it sits on the main cap. Maybe the center rod is too long?

[cadillac_al]

I would get some shims and forget it. I went through this once and blamed it on an aftermarket intake. I used the triple gaskets and don't remember messing with it again. I'm sure some nice shims would work just fine.

[kwmech]

If it were me I'd like to know what was going on before throwing a bunch of shims at it and calling it good enough.

[chewychevy67]

Tomorrow I'm going to get this figured out. I will take the pan off and take pictures if I can't figure it out. I have more time than money and don't want to get pushy with it.