Engine juddery, loss of horsepower.

[None_zero]

Damn when didbi become a senior member? Unless that just means I'm old I feel like it could be misleading lol

[None_zero]

I suppose my question should be... when do I know the needle valve is closed? Is it when the silver clip touches the housing and the brass pin starts to move independently? Or is it when the brass pin bottoms out in its housing?

[None_zero]

Or even... did you crash out on me with my carb disassembled?? Well damn time to sink or swim cause there's a problem with the float... that's a little carburetor joke for ya 

[datzenmike]

 

When the float is level like in this picture the little needle valve should be closed. Bend the tab up to adjust.

 

 

That damage on the bottom will not prevent the rubber seal working. Just make sure it's clean.

[None_zero]

Ok I did clean the seal and blew off the needle and the seat with compressed air. If you could indicate what represents closed I can open it back up tomorrow and adjust if it needs it. Since it's spring loaded is it closed as soon as the little pin starts moving independently or does that spring loaded pin need to be all the way up in there. My assumption is that the rubber tip makes contact and closes against the seat and the springloaded pin just applies pressure to it. Let me know please if this assumption is correct or incorrect. When I blew the seat out something went flying and I panicked thinking I'd blown out a tiny collar that mirrored the one on the outside of the float mounting pin. But after a few minutes of frantically searching the engine bay and grass under the truck I got my wits about me and reassembled the float and with. The float and the one collar there was no room for it to move back and forth so maybe there was something stuck in there and it blew out. I started the truck and checked for gas dripping and there was still some but it was significantly reduced from before. I'll see how it drives In the morning and let you know what happens. Thanks for all the help 

[None_zero]

I'm thrilled to finally have something I can point at and say " there, that's the problem." Problems I can generally solve except when the problem is finding the problem then my lack of knowledge on the subject gets me in trouble.

[datzenmike]

I think when the spring is compressed.

 

Look at it this way if too tight the float chamber won't fill properly and when driving or up hills under load the engine will run out of gas but as soon as you slow down it will continue to run. You are simply using the fuel faster than it can get into the carb. Just adjust the float a little lower. Might take several tries. This is why the missing window would help.

[None_zero]

Ok so after the drive to work I can say, gas mileage still not optimal. Although the dripping is much reduced. It looked like it had stopped altogether but when looked closely I think it had just slowed to where it was riding back along the injection tube and falling beneath it instead of out in front of it so I will try to adjust the float a bit today and see if that helps. I goosed the throttle a couple times while I was looking down in there and saw it misting out fuel in a pretty healthy looking fashion. I also messed with the idle mixture again since I was idling very low and noticed that I can now discern a difference when adjusting the mixture, however the highest idle I get is with that mixture screw turned almost all the way in and bottoming it out doesn't stop the engine either. The only other noteworthy thing I can think of is, I'm hearing a new sound in the engine kind of a high pitched whistle, as with in drawn air, with a little warble in it. I hear it most when I'm at the upper end of a gear about to shift or at idle. It seems to be originating from the carb itself as I could hear it more prominently when I removed the air cleaner cover.

Edited February 21, 2023 by None_zero

[datzenmike]

Too many symptoms and it's easy to get off track. The dripping inside the carburetor is something concrete that isn't right and needs fixing. This will get rid of the over rich fuel mixture and allow proper idle setting. It will clean up the spark plugs too and the oil will stay cleaner longer.

 

Whistling is probably a hose off. Or perhaps it cracked? As you had the air filter off maybe something disturbed?

[None_zero]

I have another question. When I first start the truck, should the tachometer read at zero or below while it warms up? That doesn't seem right I thought it was supposed to compensate during the "warm up" period. Just now with ambient Temps in the 60s. I started it and the rpms were registering under zero after 5 mins it climbs to 500 and if everything goes like normal here in another 5 or so it will be closer to 700 

Edited February 21, 2023 by None_zero

[datzenmike]

The tachometer reads engine RPM at all times the engine is running. Period.

 

Do your gas and temperature gauges work? If yes then the fuse is ok.

You pulled the intake and exhaust plug and tested for spark? got spark?

 

Only thing left is the tach is faulty. Appears to need some time to warm up. Try turning the ignition on for 10 min then start. If the tach works right away then it's the tach.

 

 

[None_zero]

4 hours ago, datzenmike said:

The tachometer reads engine RPM at all times the engine is running. Period.

 

Do your gas and temperature gauges work? If yes then the fuse is ok.

You pulled the intake and exhaust plug and tested for spark? got spark?

 

Only thing left is the tach is faulty. Appears to need some time to warm up. Try turning the ignition on for 10 min then start. If the tach works right away then it's the tach.

 

 

Ok. I understand the tachometer I guess what I was really asking is can the revolutions be so low that the tach reads at or around zero (not being digital) and the engine still be running. But now that I phrase the question this way I think I can answer that for myself. Yes fuel gauge works but I set the resistance myself and I think it's slightly off maybe but I'm not worried about it. It reads over full when full and hits E with just under 2 gallons in the tank. Bit yes it moves and gives a reading. Temp gauge also works faithfully rises till the pointer just touches the bottom of the temp gauge symbol. So I guess the tachometer could be bad. That could answer some things also if I'm gauging my idle speed off a bad reading. I'll test it today and make my adjustment to the float and get back with you. You want to just come to Tennessee and fix it for me? Lol  kidding I actually love this stuff, it's just harder to get to the source on this old truck because when I look at it everything is suspect. I need to just remember the things I know and go off that but for some reason. My brain is always looking for some obscure complicated problem. I plan to be driving a different vehicle to work in the near future so I can take the time to work on a bunch of the issues

Edited February 21, 2023 by None_zero

[None_zero]

Switched on about 10 mins and then started. Took photo while it's idling 

[None_zero]

After the engine is running for 5 mins or so. And in the time it took me to upload this it rose to a steady 500 rpms. And I can hear the idle speeding up corresponding to the needle rising

Edited February 21, 2023 by None_zero

[None_zero]

Once it reads operating temp on the temp gauge it will be up to about 700

[datzenmike]

It reads engine RPM. Engine temperature has nothing to do with this. Very difficult for any engine to idle below 600.

[None_zero]

Ok adjusted the float before I left town. And did appear to have stopped the gas dripping into the carb. I drove to the next town mostly uphill and it never seemed to be short of gas, never stalled out or anything. I'd tried once more to adjust the idle mix also before starting out but seemed about the same highest rpm occurs 1 or .5 turns from bottomed out and bottomed out still runs better than 3 or 4 turns out. The trip home I made was abnormal so I filled the tank before I left. I drove 11 miles and maybe a few tenths to the store and then 6.2 miles to the gas station right by my house and topped the tank. It let me add 2 gallons which works out to roughly 9 miles a gallon. If you're generous. Which is a hell of an improvement from the half tank or more I burned yesterday getting home 

Edited February 21, 2023 by None_zero

[None_zero]

3 hours ago, datzenmike said:

It reads engine RPM. Engine temperature has nothing to do with this. Very difficult for any engine to idle below 600.

I'm not saying the engine temp has anything to do with the tach. I'm saying as the engine warms the rpms go up (I'm not basing that off the tachometer, it's an audible change) and the tach does respond to that audible change in rpm. But it obviously isn't reading correctly when it says I'm idling at negative 100 rpms 

[datzenmike]

You should easily be getting twice the mileage.

 

 

Next time it's -100 RPMs check intake and exhaust side plugs for spark.

 

 

[None_zero]

Just now, datzenmike said:

You should easily be getting twice the mileage.

 

 

Next time it's -100 RPMs check intake and exhaust side plugs for spark.

 

 

Ok I'll try this you would know better than me, but I don't think that's the issue. Has new distbutor cap new rotor (changes a few months ago) spark plugs are less than a year old. One of the ignition coils is new. Plug wires less than 6 months old. I'm just thinking all the components that generate the spark are basically all recently replaced 

[None_zero]

I'm looking around at fuel pumps right now and it looks like the holley and the generic ones that look the same all have basically the same specs of 5-9psi with between 30 and 32 gph.. does that come close to the specs on the original or do you know?

[None_zero]

So here is a thing to think about. Maybe it's nothing you tell me. Originally when setting the timing the correct setting was somewhere around the middle and the tach read normal i think but somewhere along the way I did something and it changed. Now to have the timing set at 5° btdc it's maxed out all the way to one side. But the timing is set based on idle at 700 rpms right. So if I did something like say cut the wiring harness (which you may recall I did) and then struggled for weeks to get everything hooked back up correctly which I think I did eventually. At least all the lights work and the blower blows ect ect the only thing that doesn't work is the dash illumination but I'm getting off track here. Could I have done something to the wiring that would make the tach read funny (read low)? And then I've set my timing to the wrong idle speed... cascade from there?

[None_zero]

If that's absolutely not a possibility a simple no would work I'm just trying to eliminate the me factor and rule out nothing broke and I just jacked everything up here

[None_zero]

13 minutes ago, None_zero said:

So here is a thing to think about. Maybe it's nothing you tell me. Originally when setting the timing the correct setting was somewhere around the middle and the tach read normal i think but somewhere along the way I did something and it changed. Now to have the timing set at 5° btdc it's maxed out all the way to one side. But the timing is set based on idle at 700 rpms right. So if I did something like say cut the wiring harness (which you may recall I did) and then struggled for weeks to get everything hooked back up correctly which I think I did eventually. At least all the lights work and the blower blows ect ect the only thing that doesn't work is the dash illumination but I'm getting off track here. Could I have done something to the wiring that would make the tach read funny (read low)? And then I've set my timing to the wrong idle speed... cascade from there?

I realize I worded this horribly so let me clarify. The first couple times I looked at or adjusted my timing the dizzy would sit right around the middle of the adjustment range, and at that time I never noticed the tach acting funny. Now when I i check or adjust my timing it is maxed out rotating clockwise if you're looking down at top of the distributor. I've never been able to figure how or why that would have changed so drastically. I plan to check it again since we made these latest adjustments. It seemed like I was hitting the top of the gears really quickly on the drive home. Lots of pep on take off but dropping off some as I increased speed.

Edited February 22, 2023 by None_zero

[datzenmike]

Stock pump pressure is 3-4 PSI I wouldn't get anything higher.

 

Ignition wiring was cut? That's bad. The tach may be at fault but we have to discount everything including new arts, especially new parts. There is no guarantee a new part is good. If the tach isn't reading when cold then intake and exhaust coils should be checked they are firing when cold.

 

Ignition timing is 5 degrees BTDC. What did you set the timing at when it was in the middle of the adjustment range???

 

Have you had the oil pump out?