318 Engine stumble
This doesn’t make sense to me and might be a problem with timing. I can’t really wrap my head around it.
I decided to check the harmonic balancer with a piston stop. I checked it three times.
(Just to see about how far I had to put the piston stop down in the cylinder. It ended up 7/8 was the best depth for close measuring)
The timing mark on the harmonic is spot on for top dead center.
The poroblem is......in the first picture. That’s top dead center. When I start the car. It backfires out the intake horribly and barely stays running.
In the second picture. I move the distributor and the car starts and runs well. The problem is. This is where 0° is on my timing light.
0° should be represented by the first picture but it’s not. It’s represented in the light by he second picture.
I don’t know why. There’s no way I can get this properly timed until I understand the logic behind this.
This is the gm Hei style distributor. I took the points distributor out becuase the rubbing block was worn out and the vacuum advance canister was seized. So far I’ve not hooked up the v can. I’ve not gotten the total timing done yet so I’ve been leaving the v can unhooked.
Had I not checked for 0° I would have never even noticed this
Is this a timing chain problem. A distributor installation problem?did I index the distributor wrong when I put it in?
I’ll have to pick back up on the timing adjustment curve and graphing after sorting this out.
The timing chain is original.
Also.....I think what I was hearing that I thought was ping. Was the car missing. The sounds were similar.....the miss was a slightly different pitch and lower volume sound. I can tell the difference now.
........ I did break a plug in half when I ran it lean a few days ago. When I changed the jets I didn’t hook up the accelerator pump and the plugs ended up white. It left me stranded a mile away from the house. I waited for it to cool back down and ran it back home in the transition slots only. Slow moving up hill but it worked.
.......so there may be other plugs that are damaged. I only replaced that one plug. Trying to get this all sorted out before I start doing maintenance work. I’ll change the oil and replace the plugs. I want to get it sorted and then do all that so I’m not rebreakkng stuff.
I have to advance the timing a lot before it even reads 0° on the timing light when the light is set to 0°.
The pictures depict the view from the front of the engine and are accurate to what I’m seeing. I really have to move it that far away from TDC to get it to read 0° On the light.
This doesn’t make sense to me and might be a problem with timing. I can’t really wrap my head around it.
I decided to check the harmonic balancer with a piston stop. I checked it three times.
(Just to see about how far I had to put the piston stop down in the cylinder. It ended up 7/8 was the best depth for close measuring)
The timing mark on the harmonic is spot on for top dead center.
The poroblem is......in the first picture. That’s top dead center. When I start the car. It backfires out the intake horribly and barely stays running.
In the second picture. I move the distributor and the car starts and runs well. The problem is. This is where 0° is on my timing light.
0° should be represented by the first picture but it’s not. It’s represented in the light by he second picture.
I don’t know why. There’s no way I can get this properly timed until I understand the logic behind this.
This is the gm Hei style distributor. I took the points distributor out becuase the rubbing block was worn out and the vacuum advance canister was seized. So far I’ve not hooked up the v can. I’ve not gotten the total timing done yet so I’ve been leaving the v can unhooked.
Had I not checked for 0° I would have never even noticed this
Is this a timing chain problem. A distributor installation problem?did I index the distributor wrong when I put it in?
I’ll have to pick back up on the timing adjustment curve and graphing after sorting this out.
The timing chain is original.
Also.....I think what I was hearing that I thought was ping. Was the car missing. The sounds were similar.....the miss was a slightly different pitch and lower volume sound. I can tell the difference now.
........ I did break a plug in half when I ran it lean a few days ago. When I changed the jets I didn’t hook up the accelerator pump and the plugs ended up white. It left me stranded a mile away from the house. I waited for it to cool back down and ran it back home in the transition slots only. Slow moving up hill but it worked.
.......so there may be other plugs that are damaged. I only replaced that one plug. Trying to get this all sorted out before I start doing maintenance work. I’ll change the oil and replace the plugs. I want to get it sorted and then do all that so I’m not rebreakkng stuff.
I have to advance the timing a lot before it even reads 0° on the timing light when the light is set to 0°.
The pictures depict the view from the front of the engine and are accurate to what I’m seeing. I really have to move it that far away from TDC to get it to read 0° On the light.
