Small Block Timing Issues Have Got Me Stuck

I have not gotten a chance to go over there this week as my buddy was out for two weeks in the field and I was working on my heap sprinting to get ready for the 4th of July weekend and Heavy Rebel in Winston Salem.

 

Try this. While it's idling high see if it's dripping in the secondaries. Or try to seal the secondaries with your hand. Maybe the back throttle blades are open a hair. Vac leak and possible dribble of fuel. This will make the idle high and uncontrolable from the front butterflies. Back throttle shaft could be sloppy, too.

 

Here's a pic of my 50 Dodge heap and Harry's 48 Plymouth

 

I checked that already last time I was over there and the secondary's were not dripping neither were the accelerator squirters in the primary's. Its a brand spanking new Edelbrock but I haven't ruled out that there's leaks internally yet.

 

Way back in 71 I had a 340 Duster with Prestolite dual point dist that the pressed-on mechanism for the mech advance loosened and would turn on the shaft.Pulled my hair on that one til I turned the rotor by hand and found the problem.

A new dist solved that problem.

Is he running a pro-comp dist also with the intake? I heard they give some problems too

 

Yeah as a matter of fact he is using a ProComp dist with his set up, it has the built in electronics to get rid of the fire wall mounted unit that was used on the 70's era cars.

 

Here's some comments on Procomp on another Forum

 

One aspect that has not been mentioned is - Is the shaft that connects the distributor to the camshaft and oil pump timed correctly? This can and will advance or retard the mechanical timing and nothing will correct the error till the shaft is "dialled in". All sbm have the same issue regardless of engine size. I do tend though to suspect a vacuum leak and had a similar situation occur on a 351 cleveland engine once - didn't matter what we did it would not idle but under a good throttle opening would run fine - At some stage prior to us getting the engine it had backfired and blown part of the intake gasket out underneath in the lifter valley area and of coures not seen nor obvious to anyone looking at the engine. replace the intake manifold gaskets and VOILA engine good to go.
Therre again I could be wrong - wife says that often to me LOL

 

Huh? Either the rotor points at the No. 1 post with a bit of room to turn it either way, or it doesn't.

 

Pull the manifold flip it over on the bench and check for casting imperfections at the base of the runners .procomp was famous for pin hole cracks in there castings ..Just a thought.

 

my buddy will probably not want to pull off his intake again as I found a internal coolant leak and its been off once but the coolant leak was fixed with a new gasket set. This weekend I might be able to get over there and give him a hand and I am going to take everyone's advice and look over the areas I might have missed and re-check everything for this cat.

All I have to say is he better have a cold beer in the fridge for the efforts!

 

George your right
the oil pump is keyed with a hexagonal drive to the dist drive gear while the dist only goes on one way basically because it has a slot in it for the dist shaft and when the No 1 cylinder is TDC comp stroke wherever the dist rotor is pointing thus becomes the No 1 spot on the dist to start the firing order.

 

Many a sbm has had timing issues cause someone did not time the shaft correctly - yes you can use no.1 in other positions however a read of any MOPar manual will explain better than what I can here as to what is required - the dissy intermediate shaft is timed from above in relationship to the camshaft - not from the position of the oil pump hex

 

Don't do it like that
You'll have all sorts of trouble and have to post a big thread on the Hamb.
Move the gear and reset the distributor.

 

If the rotor won't line up with a post you have to move the Int shaft. If it lines up with one the engine doesn't care what post is #1. As long as you can remember or follow the wire up from Cyl #1 to the dizzy it'll work, unless someone else who doesn't know works on it....

 

Yep it should happen like that .

Now if I open the hood because of drivability issues and suspected timing causes and saw the plug wires all clocked around what is the first thing to think ???

Obvious and rational thinking is "the guy who dropped it in didnt know how or didn't care to line it up correctly." Next step in rational thinking is " what else did he touch ? And what's not done correctly there ?!?"


So we have a chat and I might say " the distributor needs to be reset and the plug wires rerouted". Seem logical ? The owner might say " It doesn't matter where #1 is as long as it follows the order". Logical as well and your argument also. That's when I close the hood and say "so how's that working out for you ?"

If by some chance it really really didnt matter at all, not the slightest little bit ever, why would the factory service manuals explain how to do this, include pictures, and have a set procedure and location. They easily could have said " drop it in anyway it fits and put #1 wire over the rotor and follow the order"

I'm not saying it won't or shouldn't work I'm saying it probably will cause you problems- probably .

 

I don't think the book covers the BB Chevy water pump on my Hemi, but it works fine....

 

Yea, speaking of those I need to pick a high volume bbc pump for my hemi-roid ass ache

 

18436572 does it really NEED to be pointed in a certain direction...

tomato tamato..

 

Agreed. When you're trying to straighten out someone else's work it's better to put things back in their proper order. To do otherwise creates a sort of mental disconnect when you're troubleshooting. If someone overlooks something this simple, what other "shortcuts" have been made before all the trouble started?

I'm especially puzzled when someone is so obsessed about having all their bolt heads indexed and their tires mounted so the lettering lines up a certain way with the valve stems but then they'll re-clock the plug wires in the distributor cap and end up with the vacuum advance wedged up against the firewall.

 

What's the reason for it not to be ?

Unless it needed done on an emergency basis at 3 in the morning on the side of the road in a blizzard with no batteries for a flashlight ....

Ok lets here just one good reason on a new build why it shouldn't be where it belongs.

 

That goes under what I said, if it won't turn change it, if it'll turn propery vs frigging with the PIA Int shaft...

 

oops race car mentality here......

 

Got it figured out!

The intake was at fault! After I re-checked the entire ignition and timing over. I basically degree'ed the engine and checked the cam & valve timing just to be sure , which was right where it should have been
Intake opened at 32deg BDTC/ closed at 64deg ABDC, exhaust opened at 78deg BBDC/ closed at 30 degATDC
I verified that the valves were reaching 0.525 lift.
Checked the dist and had no issues there, no excessive play, mag pick up was in good order and had a solid 12v incoming, coil was also spot on.
While I was reassembling the top of the motor I grabbed the I take and the runners caught my attention. I had inspected the intake several times but haven't noticed anything. Well this time I saw it , the extremely poor machine work on the intake is to fault causing multiple vacuum leaks under the manifold. I threw the intake up on my bench and checked the milled angles of the head/ runner mating surface. The angles were off on both sides and different from each other and the angle runout went from one extreme to another from from to back! Basically a warped intake manifold, first brand new one I have seen like that. Moral of this story ProComp is fucking junk, don't waste your time with them!!!
I grabbed an old Edelbrock dual plane I had sitting on a shelf and quickly cleaned it up, bolted it on and shortly after fried the engine and no issues what so ever and set the timing.




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Glad you figured it out, and now I know not to buy ProComp stuff. Oh- watch your spelling!! "shortly after fried the engine" Doesn't quite mean what you had in mind!
Ralph

 

Yeah when I had checked the manifold every time I looked for a good contact pattern left from the gaskets and they were there but I Am guessing that the gasket was crushed at one end and barely at the other.


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Glad you found it. And thanks for reporting back.

 

Old thread please delete

 

Can you lock it?

 

good thread keep it!
just read the whole thing. good info on here
just lock it