Engine Bogging?

[70NewY’ER]

Hello everyone. I own a 1970 Chrysler New Yorker with a 440 i had rebuilt in the summer of last year. I put a new Holley 4160 Street Warrior carb on it back in November. All was fine up until recently. 2 weeks when i was on the highway I stomped on the gas pedal (fully depressed) at around 50 mph and let off at around 90 mph. The engine started to bog and rev down with the pedal pinned so I let off. I tried again at around the same starting speed of 50 mph. The car didn't bog. Fast forward to last week, the engine ran a lot worse under a load. When the car hit 45-50 mph on the road the car would buck and jerk and bog. It got so bad to the point where the engine stalled. I would let the car sit and idle for a bit and it would operate fine untill it hit a steady 45-50 mph and it would act up again. I tried adjusting the float in both bowls so the fuel was just trickling out of the port hole. No change. Changed the fuel filter and nothing. It seems to be getting good flow to the filter so I dont think the pump is bad. I could replace it anyway to be safe. I checked for vacuum leaks and couldn't find any that would cause an issue like this (or so I believe). I might change the spark plugs as well. By the way I am running the newer Mopar electronic ignition system. My timing is set at 2 degrees BTDC with the vacuum advance plugged. I'm kind of at a loss and I don't want to spend any more money than i need to. Any help woulld be appreciated!

 

[CBODY67]

Ignition and fuel issues can act the same, or similar. Try a new control box, just a normal quality one from a local auto supply, see if that changed anything. Make sure the control box is grounded to the car body, through the mounting bolts, IIRC. Perhaps @halifaxhops has one for your system, if you have enough time to wait on shipping?

Just some thoughts
CBODY67

 

[halifaxhops]

Hello everyone. I own a 1970 Chrysler New Yorker with a 440 i had rebuilt in the summer of last year. I put a new Holley 4160 Street Warrior carb on it back in November. All was fine up until recently. 2 weeks when i was on the highway I stomped on the gas pedal (fully depressed) at around 50 mph and let off at around 90 mph. The engine started to bog and rev down with the pedal pinned so I let off. I tried again at around the same starting speed of 50 mph. The car didn't bog. Fast forward to last week, the engine ran a lot worse under a load. When the car hit 45-50 mph on the road the car would buck and jerk and bog. It got so bad to the point where the engine stalled. I would let the car sit and idle for a bit and it would operate fine untill it hit a steady 45-50 mph and it would act up again. I tried adjusting the float in both bowls so the fuel was just trickling out of the port hole. No change. Changed the fuel filter and nothing. It seems to be getting good flow to the filter so I dont think the pump is bad. I could replace it anyway to be safe. I checked for vacuum leaks and couldn't find any that would cause an issue like this (or so I believe). I might change the spark plugs as well. By the way I am running the newer Mopar electronic ignition system. My timing is set at 2 degrees BTDC with the vacuum advance plugged. I'm kind of at a loss and I don't want to spend any more money than i need to. Any help woulld be appreciated!

Bet the orange box is bad. Still trouble shoot it instead of just throwing parts at it.
Good book for it with just a meter

For Sale - Electronic ignition trouble shooting guide.

I have some copies of a great book for trouble shooting Mopar electronic ignition with a ohm meter. Askin $21 shipped lower 48

www.forcbodiesonly.com

 

[70NewY’ER]

Bet the orange box is bad. Still trouble shoot it instead of just throwing parts at it.
Good book for it with just a meter

http://[URL]https://www.forcbodieso...tronic-ignition-trouble-shooting-guide.80443/

[/URL]

So I had another control box laying around. It was the same type that I’m currently running. They’re both the proform brand. They seem kinda cheap if I’m being honest. I swapped it with that one and it didn’t change anything unfortunately. I’m going to check it with a meter like you were saying. I’ve read that they need a constant 12v or something like that.

Ignition and fuel issues can act the same, or similar. Try a new control box, just a normal quality one from a local auto supply, see if that changed anything. Make sure the control box is grounded to the car body, through the mounting bolts, IIRC. Perhaps @halifaxhops has one for your system, if you have enough time to wait on shipping?

Just some thoughts
CBODY67

I have it mounted right above the heater core box. I drilled out holes for it. My father did the same thing on his ‘70 300 back in the 90s and apparently it worked? Although there’s a decent amount of rust and Swiss cheese where it’s mounted. I can try relocating it to a better spot? I have a ground wire running to it as well by the way.

 

[halifaxhops]

Hate to say this the new profom boxes stink.

 

[halifaxhops]

Just caught where you live, Stayed all summers Growing up in my dad's house on Noyack Bay.

 

[Big_John]

I would check the fuel volume. Looking at your fuel filter won't tell you much.

Disconnect the coil wire first. Disconnect the fuel line at the fuel filter or carb and run a hose to a soda bottle. Crank the engine and watch the bottle fill. It should show a good stream of gas into the bottle.

If you don't have a good stream, it's something in the fuel system. It could be the pump, the pump push rod, or something in the line or tank. Even a pinhole in the line can cause these issues. The push rod needs to be checked for length. It should measure about 3.25"

 

[david hill]

Don't forget to check you fuel pickup nylon sock on the fuel tank. Collapsing rubber fuel hoses between the fuel tank and fuel pump are also prone to contributing to your symptoms.

 

[70NewY’ER]

I would check the fuel volume. Looking at your fuel filter won't tell you much.

Disconnect the coil wire first. Disconnect the fuel line at the fuel filter or carb and run a hose to a soda bottle. Crank the engine and watch the bottle fill. It should show a good stream of gas into the bottle.

If you don't have a good stream, it's something in the fuel system. It could be the pump, the pump push rod, or something in the line or tank. Even a pinhole in the line can cause these issues. The push rod needs to be checked for length. It should measure about 3.25"

Thanks for the tip. The fuel line is was replaced a few years back with a stainless unit. But who knows? There could be an obstruction somewhere down the line. I will try the soda bottle method!

 

[70NewY’ER]

Don't forget to check you fuel pickup nylon sock on the fuel tank. Collapsing rubber fuel hoses between the fuel tank and fuel pump are also prone to contributing to your symptoms.

I should check the lines going from the tank to the carb. I haven’t looked at those in a long time so it’s worth checking. I will also inspect the filter sock when I get the chance.

 

[70NewY’ER]

I forgot to mention one thing. I noticed that when I pulled the cap on the distributor there were very small but noticeable metal flakes on the advance plate (kind of like metal filings on a magnet). It looks like the pickup is rubbing against the cam and I can see wear marks on the high points in the cam. I don’t know if this would contribute to my problem because it runs and revs good when idling?

 

[Big_John]

I forgot to mention one thing. I noticed that when I pulled the cap on the distributor there were very small but noticeable metal flakes on the advance plate (kind of like metal filings on a magnet). It looks like the pickup is rubbing against the cam and I can see wear marks on the high points in the cam. I don’t know if this would contribute to my problem because it runs and revs good when idling?

Yes, that could do it and is probably the problem.

The space should be .008". Even if it's not the problem, it still should be corrected.

 

[70NewY’ER]

Yes, that could do it and is probably the problem.

The space should be .008". Even if it's not the problem, it still should be corrected.

I will check the gap. Yeah it's definitely not normal. I have an old direct connection distributor that my dad got back in the 90s. I might install that one if the current distributor doesn't react to the adjustment.

 

[CBODY67]

That gap in the distributor needs to be checked with a BRASS feeler gauge so the internal magnet does not interfere with checking the gap. Per Chrysler.

 

[cbarge]

First of all, 2 degrees BTDC with electronic ignition is way too low!
Any changes from stock ( carb, ignition) the factory timing spec no longer applies.
GEt a vacuum guage and plug into a constant vacuum port.
At idle vacuum should be at 18-20 inches at 10 degrees BTDC.
You have to test and tune, listen to the engine to see what she needs.
Try 10 degrees, drive it. No ping,no bog? Bump it up to 12. Ping? Drop down
all while reading vacuum!
THe vacuum advance should be operational.
Hope this helps

 

[70NewY’ER]

First of all, 2 degrees BTDC with electronic ignition is way too low!
Any changes from stock ( carb, ignition) the factory timing spec no longer applies.
GEt a vacuum guage and plug into a constant vacuum port.
At idle vacuum should be at 18-20 inches at 10 degrees BTDC.
You have to test and tune, listen to the engine to see what she needs.
Try 10 degrees, drive it. No ping,no bog? Bump it up to 12. Ping? Drop down
all while reading vacuum!
THe vacuum advance should be operational.
Hope this helps

Interesting. Ill to give that a try as well. I never thought about the factory timing marks being obsolete after swapping ignition systems. Thanks!

 

[CBODY67]

The reason is that the advance curve in the MP distributor is quicker and has a different total amount, the total amount of which affects the base timing to use to get to the desired approx. 36 degrees BTDC or total timing. Upping the base amount, as a result, will increase off-idle response a good bit, making it a different car to drive.

Enjoy!
CBODY67

 

[70NewY’ER]

Hello everyone! It’s been a while. Lots of things going on in my life so haven’t had the chance to work on the New Yorker. Today I decided to remove and inspect the fuel pump. What I found was interesting and I think this could be the culprit. The fuel pump push rod was considerably worn down on the cam side. About a 1/4” I’d say. I’ll attach a picture below:

The left side was the side that rode on the cam. A friend of mine from church said that he had a problem with push rods getting worn down prematurely. Is it not enough oil reaching to that spot? Also would anyone have any suggestions on where to buy a quality push rod? Thank you!!

 

[cbarge]

Worn fuel pump push rods are more common than you think.
Replacements should be easy to find.

 

[Ripinator]

Hello everyone! It’s been a while. Lots of things going on in my life so haven’t had the chance to work on the New Yorker. Today I decided to remove and inspect the fuel pump. What I found was interesting and I think this could be the culprit. The fuel pump push rod was considerably worn down on the cam side. About a 1/4” I’d say. I’ll attach a picture below:
View attachment 644358
The left side was the side that rode on the cam. A friend of mine from church said that he had a problem with push rods getting worn down prematurely. Is it not enough oil reaching to that spot? Also would anyone have any suggestions on where to buy a quality push rod? Thank you!!

Here ya go:

Fuel Pump Pushrod - New