Vacuum canister obstructed by oil sending unit

[Aar1064]

Can anyone tell me what is wrong with this picture? Original points distributor vacuum canister is hitting the rallye gauge oil pressure sending unit and I have no way to adjust timing. Should the canister be between the firewall and sending unit or should I figure out how to lower the sending unit. It's as tight as I feel it should be with out breaking.

I've looked for original pics but haven't come across any yet.

[Cuda Cody]

Small block, right? Didn't see the photo attached, but all you have to do is re-clock the gear and that will move the slot thus moving the vacuum canister.  Pull out the distributor, find the slot that the end of the distributor goes in.  Then you can take a flat head screw driver and turn it.  It will come up and move over one tooth.  make sure to mark your distributor so you can put it back in correctly.  They can only go 2 ways, correct and 180 off.

I'm running out the door right now so I'll try to find a photo when I get back.

[Aar1064]

Ok thanks Cody. I'm not much of a mechanic but think I know what you mean except which part of distributor needs to be marked?

Is the objective to get it Between firewall and the sending unit?

[Cuda Cody]

@Aar1064  Can you get a photo from a little lower?  Not sure why your canister is hitting?    I still think you can adjust you drive shaft to get the canister to move to where you want it.  Just make sure you keep the end of the distributor lined up with the "slot" in the oil pump drive shaft (see red arrow).  If you don't mark it and put it back in the same way, the timing could be off by 180 degrees.  You see what I mean about it going in only two ways?  The right way and 180 degrees the other way.

[Cuda Cody]

Not sure who's video this is, but you can see what the oil pump drive shaft looks like and what you are trying to "re-clock" so the slot puts the canister in a different position.  You need to pick it up slightly so the gears are off the cam and realign it in a new position.

[Burdar]

I believe the factory assembly line sending units are shorter then aftermarket sending units. That's probably the issue. Reindexing the intermediate shaft should work.

[Aar1064]

Ok got it. Thought that's what you meant but wanted to make sure. To be sure, just make sure the distributor shaft doesn't turn 180 while its out. Original distributor must be a little shorter than electronic in pic. Another pic when engine was out.

[Aar1064]

I believe the factory assembly line sending units are shorter then aftermarket sending units. That's probably the issue. Reindexing the intermediate shaft should work.

I never thought of that. I still have original and will compare them. I'd rather try to fix the clearance issue before reindexing the shaft. Look at me using terminology I've learned from you two.

[anlauto]

Is the car running and the timing set right now ? Because I've run into this before and the vacuum advance should be on the other side of the sender closer to the firewall in my opinion.

[Cuda Cody]

   You're going to need some room to adjust it when it's running.  On the other side of the sending unit should give you more room.

[RUNCHARGER]

Do you have a factory manual to see if your spark plug wires are indexed 1 place out? That distributor should be turned 1/8 of a turn it looks like to me and if it's timed correctly then maybe your plug wiring is 1 out or the distributor drive gear is installed incorrectly.

[Aar1064]

@anlauto Yes it's in car and running now. Timing is set good enough to run but not quite right yet. Ok so canister needs to closer to firewall.

[anlauto]

Well if that's the case then I think you need to adjust the distributor drive gear as suggested

[Brads70]

Can you tighten the sender enough to get the required clearance? Just a thought?

[Aar1064]

@anlauto I'll try this sometime this week and report back.

@Brads70 I've tightened it as far as I feel comfortable with.