tool

I have a 1969 C50 Chevy that I use regularily for hauling water.

It has a 350 Chevy with 5spd tranny and 2 speed rear end.

It was running poorly, backfiring through the carb etc. Figured she needed some ignition timing work.

Removed cab and rotor and everything looked gross, advance weights seized up etc.

So I figured I'd update with an HEI distributor.

After purchasing MSD Streetfire distributor and removing old unit I find that the oild pump drive is not the same.

Purchase new oil pump and driveshaft.

Remove pan, oil pump and its driveshaft and install new distributor only to find it won't sit down all the way and has about an 1/8 of an inch gap between bottom of distribtor housing and intake manifold?

Wiggle it lots, can't get it to sit down yet....

Rotor feels like cam/distributor is engaging something but still can't get it to go down all the way.

Bump the starter slightly and still no joy... AND rotor hasn't moved from my mark.

So 2 questions.... Am I going to be grossly out of time now? and what the heck am I doing wrong that distributor won't go down all the way?

Any help is greatly appreciated.

j_martin

Used to work on em a lot. Been a looooong time, but I think I remember the slot being slightly offset.

Anyway, after messing with the starter, you need to find TDC #1 and make sure the distributor is pointing at the right wire. You may have to rotate the wires if the distributor is significantly different.

tool

Sorry, I don't think I follow you? Which slot is offset?

Bark

I know this doesn't help but its weird.
I replaced the distributor on a 68 with a Taylor HEI and it matched the old oil pump drive just fine.
In fact I lucked out and only had to pull it out once to get the gear lined up in the right spot and barely had to rotate the crankshaft to get it to drop in the last little bit.
Also, if you have the casting mark on the side of the distributor shaft lined up with the dimple on the gear and install the distributor with the casting mark facing forward while the timing mark on the balancer is lined up at timing mark 0 on the compression stroke it is at TDC number one cylinder so you shouldn't have to shuffle any spk plug wires around.

patdaly

Long time Chevy dude, I can stab em in in my sleep.

Somebody is jacking you, there never was a different pump and drive for small blocks, only steel sleeve for HD use and plastic sleeve for pedestrian use.

Can you post up pictures of the HEI? The reason I say this is the drive has nothing to do with the rotor moving, it has everything to do with driving the oil pump, and by the time you were within 1/8" of being down, the gear should have been engaged to the camshaft.

Compare the lower of the HEI to the lower of the dizzy you just pulled out.

They should be identical.

Also, when you get this thing installed finally, don't forget you have to get rid of the resistance wire on the run side of the circuit for it to run right. We used to just pull a new switched wire rather than try and cut and splice the original one.

soulezoo

I'm going to add one other thing.

You mentioned in 1st post that it was backfiring through the carb. While the evidence of gnarly stuff under the distributor cap indicates that is your problem, it is also very probable that the cam has slipped a tooth in the chain. If after having the distributor in and correctly set you still have similar problems, look to the cam, check the chain for stretch and that the gears line up correctly.

tool

No they are not, definitely a different oil pump drive shaft.

The old shaft has a rectangular style end, rather than the slotted two tang style like most other small blocks.

The Couplers on the end of the distributor are almost inverse of each other.

If and when I do get the HEI setup to work, the HEI requires full twelve volts, so no resistor wire for sure.

I will try to attach pics of the distributor drive gears and engine oil couplers.

patdaly

Well, sonny mick....... Learned something new today!

Evidently GM DID have a different drive on medium and heavy duty trucks!

http://67-72chevytrucks.com/vboard/s...d.php?t=376127

http://talk.newagtalk.com/forums/thr...ed&setCookie=1

Both claim to have just swapped the gears on the dizzy, but I fail to see how that would work without cutting off the tang on the HEI...... And no way would I do that without knowing it would work for sure, gotta do a bit more reading.

One thing is for sure, when you think you have seen it all.......

On edit, went back and re-read closely, the only successful conversion using the old gear was the guy who cut the tang off, no go in your case since you already changed the pump and drive.

patdaly

Now, on to getting it going, you say you bumped the starter, how much? If you barely hit it, then it might have moved, and rolled back. If the gear was actually engaged, then you should be able to roll it over and not lose time. As you roll it, it will naturally try and suck the dist. down, not up.

I would either roll it over at least a couple of revolutions by hand ( socket on the crank ) or just hit the starter and roll it a couple of revs.

Then see what you have and let us know.

tool

Oh did I mention that it is dark, 15f, with blasting snow and I'm working outside on this?

rockcrawler304

Brrrr.... I did notice the gloves!!


Also if you turn the engine over by hand I would recommend pulling the plugs. Makes it easier and they will most likely need to be replaced and re gaped anyways. And just in case, the firing order is 1 8 4 3 6 5 7 2

Bark

Shows you what I know. I thought all the small block V-8's from around 67 to 79 used the same gear set up.

patdaly

But of course, Mr. Murphy is kind to all of us who procrastinate.........

Not laughing, I am right there with you, I have a 3 car garage, a 40X60 pole barn with concrete, insulation and wood for heat, and I am working on my junk outside as well...........

patdaly

Actually, 55 till the 90s............. Unless you had a HD truck.

One other thing I had clean forgot was at least the BB HD truck engines used a gear drive cam, which made it turn backwards ( no idler ) so those had one more strike against them, a reverse rotation gear on the Dist.

Obviously the small block didn't do the same thing.

tool

Well I got the distributor in and I think I have it timed for about 8 degrees initial.

Hoping that should be close with an HEI setup?



So.........

Anyone want to guess why I couldn't get the distributor to sit in all the way?



Still guessing????



It's because I'm a MORON!

While I was trying to make the new HEI distributor work with the original rectangular oil pump driveshaft, I removed the gear and tried to swap it with the one of the original distributor. It didn't work because the holes weren't drilled in the right place.


When I put it back on I put it onto the HEI distributor I put the gear on UPSIDE DOWN!!!



WHich is why it wouldn't set down all the way.

Did I mention I was doing this outside in the dark with a trouble light in a snow storm and it dropped to 5F?

Anyway, I think it should work now, just have to slap new oil pump in and put the pan back on.

What an ordeal.