What egr setup?
What distributor setup?
What carb, choke, intake?
Is the vacume ball MIA?
What cam, cam gear, rocker/pushrod/spring modification?
Other engine modifications?
Does it run rough just at idle or though the entire rpm range.
If you say hold it at 2000 etc does it want to surge?

 

It was a non running project when I bought it. Supposedly it was a crate engine. I found the pistons are .030 over sized. I checked the crank to see if it was a 400 crank thinking it was a stroker motor. It's a stock 350 crank. There's no egr. I'm running a HEI distributor with an edelbrock carb not sure what size). Not sure about if it's a bigger cam or not. It's mainly just rough at idle. The few times I drove it, other than what looked like a little blue smoke on acceleration it seems to run fine with no surging or misses.

 

I would first just look at the ignition as a unit. Cap, rotor, coil, wire, plugs - all good? If everything checks there, then it might be time to run thru the carb and make sure it's clean and right. Sometimes the timing looks off just to get the engine to run, once the issue is corrected then you can usually bring the timing in where it needs to be.

 

Ignition system is mostly all brand new and in good shape. Since I'd like to make this a reliable daily driver, I'm half tempted to put a holley sniper kit on it. That should eliminate all the variables in the fuel system as well as give me more data to be able to try and trace what's going on.

 

Thanks for the chuckle!
you can’t get it running so throw 1500 bucks worth of stuff on it.
That’s a good plan!
Dig deeper!
Could be as simple as rockers all adjusted wrong.

 

With the timing mark and pointer aligned where is the distributor’s rotor pointing with regard to the number 1 plug terminal on the distributor cap?

Bogie

 

With #1 at TDC the harmonic balance was pointing at 0* and the distributor was pointing at the #1 wire.

 

MIght sounds like a stupid question but what method did you use to get the number 1 piston exactly at TDC?

 

I put a scope through the spark plug hole to watch when it was a TDC.

 

Not near good enough, the crank swings an easy 15-20 degrees with no really visible piston motion. This takes doing the positive stop method to which the greater the camshaft timing the smaller the margin of error for the setup and tune.

Being off as much as you are seeing is saying something is way off.

The vacuum gauge is saying something is way off as the how far you need to set the timing from the marks. This could be the distributor off s tooth which is pretty common. There are two elements that need to be indexed these are distributor housing to a fixed point and the rotor toward the number one cap terminal. A general guide is the vacuum canisters nipple is pointing at the number 6 spark plug while the rotor is pointing at the number 1 spark plug. A carpenter’s string line may help with this setup.

You can count on that removing the distributor will always pull the oil pump shaft just enough that reinsertion is a tooth off. The trick here is if you made index marks for the housing to manifold and rotor to distributor before pulling same distributor and not having rotated the crankshaft the engine is still timed. Then when dropping the distributor in with the housing marks to manifold aligned you’re in good shape in spite of the rotor isn’t quite aligned to the number one mark you made. The trick here is to turn the crankshaft in the normal direction of rotation which is clockwise viewed from the front of the motor for road vehicles and many boats. When the distributor drops all the way to the intake without you otherwise fiddling, it is timed correctly.

I and several we’s are harping on this as the first order of business is to insure the ignition is properly timed. Once we’re all satisfied then we can deal with headaches of what if anything the vacuum gague is showing to be odd.

Keep in mind since you didn’t build it is the need for the cam to be properly timed to the crank. The books say to set up the timing set with both the crank gear and timing gear pip marks at the noon o’clock position for a 12 hour clock. The problem with accuracy is six inches and some mechanical interfering parts with seeing how accurate this is. A better method times for number 6 firing; this has the pip marks directly across from each other with the crank gear at high noon and cam gear at 6 o’clock. Just plain makes it visually simple. Once you have this, one crank revoluton in the clockwise direction has it set back to number one firing.

Keep in mind the camshaft is nothing more than a drive shaft for the distributor the functions of timing the cam to the crank and the distributor to the crank are independent of each other, so it is possible to have the cam out of time while the distributor is correctly timed, or vice-versa.

So these are helps at getting to being sure the cam and distributor are correctly timed, which is the first order of business.

Bogie

 

I have a thought, make sure your timing light plug wire pick up lead is on correct spark plug wire. If you mistakenly put it on cylinder number 3. I think it’s would read like it is. If my math is correct your balancer mark would be some where around the 11 o’clock position

also stay away from sniper unit, look up the post on 77 Grand Prix

 

Could be stuck advance in the distributor.

 

Some SBC balancer were marked for having a timing pointer at the top of the cover, looking behind the water pump. Sounds like you are using one of these balancers with a conventionally placed timing pointer.

 

That's what I thought as well but when I manually lined everything up the balancer was aligned with the marks on the timing cover.

 

Probably you should check it with a piston stop. Careful not to damage a piston (pull all plugs to roll it back and forth).

 

Simple solution is to mark YOUR balancer per YOUR timing tab at TDC, using the piston stop. A line of yellow paint on it will be fine .......

 

Find TDC correctly with a piston stop and then degree the cam. Don't trust timing marks!

 

I've got a 47 chevy with a sbc 350 in it. The engine won't run unless the timing mark is about 2-3 inches counter Clockwise from the timing tab. I know there are 2 different style harmonic balancers but when I verified when #1 is at TDC the timing mark is pointing at 0* on the timing mark. The engine runs like crap and I'm trying to narrow down reasons why.

On a side note maybe related, maybe not.... when I hook a vacuum gauge up to the carb it's very irradic. I'm planning on doing a compression test this weekend to check the valves and whatnot. I've sprayed starter fluid with the engine running with no results so I'm not sure it's a regular vacuum leak.

I would say that the distrubtor is off by one r two teeth in oil pump check rotor when number one is at Tec see where rotor is pointed at should be number 1 spark plug if not may have to pull dist out and adjust for time

 

I would say that the distrubtor is off by one r two teeth in oil pump

From a TIMING standpoint, which teeth are engaged does not matter at all.

Obviously you don't want the vacuum canister up against the firewall or aimed straight forward. But if the rotor is pointing at the #1 plug tower at TDC #1 compression stroke, it doesn't matter which teeth are engaged or which plug tower you use for the #1 plug wire.

I like to do it like GM did and as Bogie mentioned above, but that's purely cosmetic unless the canister hits the firewall, etc.

 

I've got a 47 chevy with a sbc 350 in it. The engine won't run unless the timing mark is about 2-3 inches counter Clockwise from the timing tab. I know there are 2 different style harmonic balancers but when I verified when #1 is at TDC the timing mark is pointing at 0* on the timing mark. The engine runs like crap and I'm trying to narrow down reasons why.

On a side note maybe related, maybe not.... when I hook a vacuum gauge up to the carb it's very irradic. I'm planning on doing a compression test this weekend to check the valves and whatnot. I've sprayed starter fluid with the engine running with no results so I'm not sure it's a regular vacuum leak.

You might want to read the notes here,it is one reason some will use this balancer that has 3 different keyways. Professional Products 80000: Powerforce Harmonic Damper Small Block Chevy 283/327/350 - JEGS High Performance

 

Yeah I think I related the story of when I replaced the 4L60E in Frankenmouse with a 700R4. In my all night working state of super tired I lost count of my crank turns while tightening the converter to flexplate bolts.

So when I got topside I dropped the distributor in for what I thought was number 1 firing but it turned out to be number 6 is where the engine came to rest when I was done screwing around with the converter. Few hours later I tried to fire it up and was greeted with an explosion out the intake. Figuring my mystske and not doing any more investigation than it took to get into this problem in the first place, I pulled the plug wires out of the cap stuck number one’s wire into the number 6 tower and counted the firing order out from there. Crawled back in the cab hit the starter and it fired right up.

I set the base timing and left it like that till the next tune up, for a customer I’d fix it no matter how tired i was but for myself if it works just leave it till later.

Bogie