Jerking While Driving and... Stall

[Scotty]

It's not polite to cast aspersions at my metaperspective.

That's how untrue rumors can be started online about someone who you only know because of innuendo from someone whose information they can't be sure is truthful - or just carefully edited.

Maybe you should really read the two quotes in my signature and think about what they mean and imply.

Sore subject - and it's not LOL

...my apologies. Did not mean to offend you. I have the highest respect for you and was being funny but I need to pay better attention and care to that...



Pain shared is pain lessened; joy shared is joy increased. Thus do we refute entropy. - Spider Robinson

 

[husky drvr]

Apology accepted. Offended - not really. Perplexed why a perceived violent act is humorous, but not funny.

Interesting quote.

Here's one for you. I doubt you'll be challenged in determining the author.

"There should be a science of discontent. People need hard times and oppression to develop psychic muscles."

 

[DAVID LAWLER]

Hi,

I have been following your posts and based on your last comment, I thought I should let you know of my last Saturday's experience in case it helps. The set up on the "Orange Blossom" is a 1725, log type intake manifold, forty three year old Weber, well insulated mechanical fuel pump, manual choke, and electronic ignition.
This car was brought out of rather ugly storage about three years ago. We managed to get it to run rather well and took it to the United 39 in Canada. However it had a annoying hesitation (wanting to stumble - stall) when ever you made a change like starting out or shifting gears. We increased the idle speed with the mechanical Idle adjustment screw that contacts the fast idle cam. We learned to drive effectively it in spite of the annoyance.
My sense was the same as yours. it seemed if it needed more fuel at that point where it stumbled or hesitated. I rebuilt the Weber, and after looking at Weber books, the internet and such we confirmed that the best spot for the mechanical idle screw was - with no choke, it should not touch the fast idle cam, but be only off of it by a couple of thousandths. At this point if the vacuum connection to the distributor were to be disconnected and replaced by a vacuum gauge you should not have any vacuum. After several trial runs of about three miles each, and constantly backing out the idle fuel flow screw, the stumbling started to become progressively worse.
Finally the light bulb lit - I came to the conclusion that the needing more fuel must be an incorrect conclusion, and that the center two cylinders were getting much too much fuel because of the log manifold. We reversed tactics and went back to the starting screw position and then closed the screw by a half turn, Results somewhat better. Played with it more, and with a few more test runs, the nagging problem went away.
I had it out today with a new, but experienced, driver, for about thirty miles in reasonable traffic. There were no signs of the hesitation or stumbling. I hope this is of use to you.

Dave Lawler

 

[Tim R]

Scotty, In your post at 3.24 on 02/08/24 you state that you do not have an insulator beneath the weber, only the gaskets. Your car will NEVER run correctly regardless of whatever else you do without a proper insulator there. It is vital. None of the other suggestions and ideas that are proposed are worth bothering with until AFTER you have a thermal insulator installed. You are just wasting your time (you need one between the fuel pump and block too).

Tim R

 

[BEpine]

Tim,
Looking at your picture, the hose from your valve cover just vents to air below the engine. You should attach it to the air cleaner so your sucking in clean air to your engine. the way I see it routed your pulling dirty air into your crankcase at the valve cover then exhausting it out through the tappet cover vent port.

 

[Tim R]

BEpine, without the suction of being attached to the inlet manifold I'm not sure that anything is being sucked in anywhere. If I put my fingers over either pipe at tick over there is no sucking (or blowing) you can just feel the air pulsing a little.
Having read the comments and advice on here I am looking to source a PCV and give it a go.
Tim R

 

[Scotty]

I took a few days, walked away from the car and got my head right. I’ve been posting dumb questions and even taking dumber takes at the car and for that I apologize. It's been a stressful month and I've been literally and mentally all over the place in general.

I took time, sat down, read up, did research, watched videos. Came back to it yesterday with a more organized mind. Here we go:

1. Compression is 165 on all cylinders.
2. Car starts up cold at 50 psi, hot at 40 psi.
3. Tested battery charge and then power to the ignition and coil. All over 12 volts.
4. Took apart the distributor plate, cleaned up the plate and oiled the distributor. Put everything back in.
5. Top dead has #1 at the bottom right (edit) of the distributor, so it is for some reason 90 out. Static timed at 8 degrees before top dead center.
6. Used a Multimeter set on Ohms to check connectivity between the distributor cap and the wireset. All are from 3-6, which is supposedly the average for this kind of testing according to online sources. If this is in error, do correct me.
7. Cold and hot set the valves at 12 and 15. About half of the valves seem to be way too tight, so I adjusted them according to Tim’s video.
8. Took the top off the Weber 32/36, checked the float and found the needle valve itself opening far too much. Adjusted the float so that it is 35mm closed, 51mm open and 2mm for the needle valve.
9. Base set the weber at 1-½ Idle in, 2 Mixture out.
10. Re-tested the fuel pump itself and it pumps a steady stream for 30 seconds. I noticed under the oily gunk on the motor a bright orange spacer between the pump and the engine which I hadn't seen before.
11. Replaced all the hoses from the hard line that comes into the engine bay from the line to the tanks, to the pump and to the Weber. Found one hose that looked fine but was split inside.
12. Disassembled, cleaned and reassembled the original PCV valve. Bought a new hose and reinstalled the unit on the car.
13. Dumped the 20w50 and replaced it with Shell Rotella 15-40. Both times I put 20w50 in weird stuff started happening like the car didn’t like it. Also went with 20w50 because I kept having low oil pressure and many folks were using it and recommending it. Now that oil psi is staying up where it should be, I have no more reason to do this, especially since it needs to be 60 degrees outside for it to be optimal. Also, the valves have so much oil on them as opposed to how ‘dry’ they looked before. I didn’t see that but now I see what they were talking about.

And then - I started the car.

With the car stone cold, the engine shakes a bit more than it should but not as violently as it was. Choke for the first time ever actually WORKS. Car absolutely hates full choke, but now it won’t stall out. It prefers a quarter or half choke. As it warmed up, it got smoother.

Car warms up and idles at 900 on the dot.

I haven’t driven it yet, but it seems to run fine now. We’ll see if I feel the same after driving it.


Things being added:

1. Ordered a Plenum for the base of the Weber.
2. Replaced Starter, which was intermittently grinding and somehow getting stuck.

 

[husky drvr]

Just some comments>

Compression is 165 on all cylinders.

a little low but even is good

Took apart the distributor plate, cleaned up the plate and oiled the distributor. Put everything back in.

very good - any chance you checked for shaft bushing wear while there?

Top dead has #1 at the bottom left of the distributor, so it is for some reason 90 out. Static timed at 8 degrees at dead center.

90* out implies that #1 was at top left or lower right - where was it?

a bright orange spacer between the pump and the engine

thought you had one - just couldn't be sure from the one pic I could check

Car warms up and idles at 900 on the dot.

try to drop to 700 +/- 50 for your weber. 900 is for the side draft CD150's


You're doing well. Keep going.

 

[Scotty]

Just some comments>


a little low but even is good


very good - any chance you checked for shaft bushing wear while there?


90* out implies that #1 was at top left or lower right - where was it?


thought you had one - just couldn't be sure from the one pic I could check



try to drop to 700 +/- 50 for your weber. 900 is for the side draft CD150's


You're doing well. Keep going.

Thank you!

I checked the bushing, the springs and the plates and it all looks good. The distributor was rebuilt back in 04 but only has 500 miles on it.

Before I got injured, I was ambidextrous, so I never really paid much attention to my left and right and my post shows it once again. My distributor is 90* out with #1 at lower right. Sorry about that, I'll try to watch my left and right a bit more closely.

I adjusted the valves again today after it warmed up and, although it sounded better, it still seemed abit off. Found two valves that once hot were way out and adjusted them. Now it runs better.

Tossed out the plastic fuel filter and put one of the Wix 33031 in its place. It sits nicely where the plastic filter was and makes some distance between the fuel hose and the engine.

I got a vacuum gauge and am reading up on that, but that's something for another day once everything else is sorted out first. Trying to focus on one battle at a time.

 

[beamdream]

Vacuum gauge is good; my "go to" for tuning. It can tell you lots of things about your engine.

Without getting too deep, my basic aim is to get the engine running steadily at idle with about 20 - 22 inches of vacuum on the guage.rstly you need to find a good source of vacuum on the inlet manifold, typically the port for power brakes is a good start, I've even used the fuel drain port on the underside of the manifold. It's important that the vacuum source comes from below the throttle plate, ie the distributor vacuum line is above the throttle so not useful.

With the engine at warm idle (around 900 rpm), turn the distributor base (which needs to be a little loose) slowly forward or back until you get a steady reading, near 20 - 22 in. The idle mixture screw will also influence this number, so it might be a matter of adjusting both units to get the best result.

The important thing with using a vacuum gauge is to finish up with a nice steady reading at idle around the 20 - 22 in. mark; so in essence I use this method to fine tune the timing and mixture settings, rather than the book figures.

If you can't achieve this, then you can do an awful lot of troubleshooting with the vacuum guage; plenty of info on line, but it's probably beyond the scope of this conversation.

Oh, don't forget to lock down the distributor when you're done

 

[Scotty]

Updates:

I drove the car at the beginning of the week, 7 mile trip out, parked for a bit, brought it back. No problems.

I decided to take it to work on Thursday. The day went like this:

Drove to work (7 miles). No issues.

Went to lunch (2 miles round trip). No issues.

Brought it home an hour later. Almost got home and it started to do the jerky dance but it wasn't as bad, the car was fighting to keep going and then... stall. No bubbling in the glass dome. Stalled twice on me in the four blocks it took to get home.

Today I went and checked the engine. The glass dome fuel pump was empty and it would absolutely not hand-prime. Did three cycles of three pumps on it at 1 minute intervals. Nothing. It took about two minutes to start it, engine shook before I could get choke to smoothen it out. From there, it idled up fine.

All the wires from the battery forward have been replaced. New Coil, new distributor cap, new wires, new plugs, cleaned out and oiled distributor. Everything reads right, from the ohms with the cap and wires connected, the coil when on and when the car is running, etc. etc. The Weber has been gone through and am in the process of installing the plenum for it (coming Tuesday!).

The one thing I haven't replaced is the actual 'key' ignition switch, which I might do today. Thoughts on this?

At this point, I am leaning heavily on the fuel pump being goofy. While I checked the fuel pump and it does flow, I have to ask: How much flow should I be seeing from it. If I hook up a vacuum gauge, how much should it be pulling?

My main fear is the possibility that its leaking gas into the crankcase.

 

[bernd_st]

After all previous discussions in this thread it seems we are getting closer to your real culprit. Appearantly you have intermittent up to no fuel supply. This can be either a faulty fuel pump or a partially blocked fuel line from the tanks. Did you ever refurbish your tanks incl. a new coating ? If not the probability is high. The latter one is a very common problem on all late series. Paint flakes tend to block the outlet on the interconnection pipe between the tanks and check the flow. Disconnect the fuel line in the rear at the outlet. You may poke it free with a piece of cutted wire cloth hanger...

 

[hartmandm]

When you finally got the car home on Thursday and turned it off, did you then look at the fuel pump and see fuel in it? And the car has sat since Thursday and today there is no fuel in the pump?

I don't think you should do anything with the ignition switch at this point.

 

[Scotty]

When you finally got the car home on Thursday and turned it off, did you then look at the fuel pump and see fuel in it? And the car has sat since Thursday and today there is no fuel in the pump?

I did and there was.
Correct. The glass was abit foggy and it was empty.

I don't think you should do anything with the ignition switch at this point.

Gotcha. Thank you for that and your post.

 

[hartmandm]

Based on your Parts Wanted post, it sounds like you are rebuilding your fuel pump. With the fuel disappearing from the fuel pump a rebuild sounds like the next step.

I've seen a couple of posts in this thread asking if you might have paint flaking off from your gas tanks, but I don't think you have responded. Do you still have the original black paint inside the fuel tanks or have the tanks been removed, the paint cleaned out and the tanks then sealed?

 

[Scotty]

Based on your Parts Wanted post, it sounds like you are rebuilding your fuel pump. With the fuel disappearing from the fuel pump a rebuild sounds like the next step.

I've seen a couple of posts in this thread asking if you might have paint flaking off from your gas tanks, but I don't think you have responded. Do you still have the original black paint inside the fuel tanks or have the tanks been removed, the paint cleaned out and the tanks then sealed?

The tanks and pipes were removed, cleaned out and recoated internally. I haven't seen debris in the fuel filter or the fuel pump, so I'm assuming the tanks are fine.

I'm taking my time right now to figure out why this is all happening before I tear things out. I got the rebuild kit because I wanted options, same reason why I'm sitting on an Electric Fuel Pump and 1-5 psi regulator.

I don't want to go through all the work of redoing things just to find out it's something dumb like a vacuum leak or a shorted cable.

 

[bernd_st]

If the tanks, pipes and the rear fuel line are clean the focus moves towards the fuel pump. To make entirely sure would check the incoming flow once the incoming line is disconnected.Think it should be rather easy to distinguish whether the engine dies out from fuel starvation (doesn't take any throttle and dies in a few seconds) or from ignition fault ( dies immediate)...

 

[beamdream]

And then there's the fuel filler cap; have you thought to check if the vent hole in the cap is clear ? Also have you checked to see if there's a "whoosh " noise if the filler cap is removed straight after shut down ?

As others have said, leave the ignition switch alone - particularly if you're seeing an empty glass on the fuel pump.

 

[Shannon Boal]

Updates:

I drove the car at the beginning of the week, 7 mile trip out, parked for a bit, brought it back. No problems.

I decided to take it to work on Thursday. The day went like this:

Drove to work (7 miles). No issues.

Went to lunch (2 miles round trip). No issues.

Brought it home an hour later. Almost got home and it started to do the jerky dance but it wasn't as bad, the car was fighting to keep going and then... stall. No bubbling in the glass dome. Stalled twice on me in the four blocks it took to get home.

Today I went and checked the engine. The glass dome fuel pump was empty and it would absolutely not hand-prime. Did three cycles of three pumps on it at 1 minute intervals. Nothing. It took about two minutes to start it, engine shook before I could get choke to smoothen it out. From there, it idled up fine.

All the wires from the battery forward have been replaced. New Coil, new distributor cap, new wires, new plugs, cleaned out and oiled distributor. Everything reads right, from the ohms with the cap and wires connected, the coil when on and when the car is running, etc. etc. The Weber has been gone through and am in the process of installing the plenum for it (coming Tuesday!).

The one thing I haven't replaced is the actual 'key' ignition switch, which I might do today. Thoughts on this?

At this point, I am leaning heavily on the fuel pump being goofy. While I checked the fuel pump and it does flow, I have to ask: How much flow should I be seeing from it. If I hook up a vacuum gauge, how much should it be pulling?

My main fear is the possibility that its leaking gas into the crankcase.

Vacuum testing of fuel pump, two types of tests. 1) dead-head, removed inlet pipe and plumb gauge to pump. Good pump will suck 18 inches and HOLD Vacuum. Should not leak down. You can do this with pump out on bench or or engine cranking with starter motor or with engine running. The hardest test is next, and is the only way to find an intermittent loss of fuel flow due to debris clog in tank. Plumb a tee fitting at the fuel pump inlet and connect gauge, routing it to be visible while driving. This measures resistance to flow in the fuel system. Duct tape gauge to the windshield or whatever. You should see about two inches of vacuum or less while driving, regardless of fuel demand. DRIVE that thing until malfunction occurs. I did this on a customer's Dodge 35 years ago. That one hit twelve inches of vacuum when going into fuel starvation, but first felt symptoms at six inches of vacuum. That one had rust flakes being drawn to sock type filter in the tank. The flakes would drop away from the filter while sitting overnight and gradually build up on sock while driving (that took 20-30 minutes) until restricting flow.

 

[glassman]

Hello. I had the same issue with no gas showing in pump no gas pressure. I rebuilt pump pretty easy. The lids over the seals I just reamed the pot metal opening with razor knife just enough, crude but safe ping back. 60 years old probably tired anyway. I just like the look, works just fine now. If you have electric one on shelf there's your backup. I know you have a gut feeling it's the problem, check it off your list. Best Regards