pb4ugo
SILVER Star
Make sure that the carb is wide open when the accelerator pedal is held to the floor.
45 mph Top Speed, what's wrong here? (1 Viewer)
- Thread starter southern son
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- Thread starter
- #22
Thanks to everyone for the replies, I will be working through all of it to make sure over the next week.
I can say that the carb is opening all the way and throttle pedal is all the way down. I adjusted all of that when I rebuilt the carb earlier in the spring, or should I say that I rebuilt one that had "just been done" according to the PO. I'm pretty sure that thing hasn't been apart in a long time.
I can say that the carb is opening all the way and throttle pedal is all the way down. I adjusted all of that when I rebuilt the carb earlier in the spring, or should I say that I rebuilt one that had "just been done" according to the PO. I'm pretty sure that thing hasn't been apart in a long time.
I’ll chime in and agree that it may be a timing issue
JohnnyC
Long ago TLCA# 2231
Do you have mechanical or vac secondaries on your carb?
I would definitely check it’s not in 4wd ... doesn’t necessarily mean its not engaged if you think it is not shifted in
If you get my point
Can you rotate the front shaft?
I would definitely check it’s not in 4wd ... doesn’t necessarily mean its not engaged if you think it is not shifted in
If you get my point
Can you rotate the front shaft?
Everyone knows they’ll go 85mph all day long in 7-man foam seat comfort.
On flat ground and if I had the testicular fortitude to do it, I know my 1F will wind all the way out to redline and defientley hit the 88MPH or more advertised top speed. With my slightly taller tires who knows, maybe I could hit the 100 mark on the speedo. Final drive calcs say its possible. 60-70 MPH is easily held, even with a strong headwind, and it holds it well even at 6000+ feet. But if any hill comes along of any significance we are knocked back to 45-55 quite easily.
I know you mentioned it, but double check the throttle is opening all the way, however on flat ground you should only be running at partial throttle once you get up to speed. You mentioned flat out all you got was 47, was the pedal to the floor? Timing is the next thing to check, if you have a dial back timing light you can rev the engine with the diaphragm off the advance or retrad plugged (we don't know what you have) and see if it is advancing the timing and at which engine RPM. At 2000 RPM shoot for 20-25 degrees of total advance, and at least 30 or more at 3000RPM. If you are not getting anything close to that your distributor is not advancing properly.
The truck will be loud, are you holding back. At 2500 RPM the engine sounds pretty spun up, I usually shift there, and there is a bit of lull in power as you rev up more, but then it kind of comes back as you go past 3000 RPM. Does is sputter, cough thru the carb, act lean.
I know you mentioned it, but double check the throttle is opening all the way, however on flat ground you should only be running at partial throttle once you get up to speed. You mentioned flat out all you got was 47, was the pedal to the floor? Timing is the next thing to check, if you have a dial back timing light you can rev the engine with the diaphragm off the advance or retrad plugged (we don't know what you have) and see if it is advancing the timing and at which engine RPM. At 2000 RPM shoot for 20-25 degrees of total advance, and at least 30 or more at 3000RPM. If you are not getting anything close to that your distributor is not advancing properly.
The truck will be loud, are you holding back. At 2500 RPM the engine sounds pretty spun up, I usually shift there, and there is a bit of lull in power as you rev up more, but then it kind of comes back as you go past 3000 RPM. Does is sputter, cough thru the carb, act lean.
Check for exhaust restrictions as well. Does your exhaust heat control valve function?
If you don't have a dwell meter and timing light, now is a good time.
Electronic ignition makes a mechanic lazy about things like ballast resistors, capacitors and coil saturation time.
Change the filters, air and fuel.
Just mentioned was an exhaust restriction. I'd also look at plug condition and gap and perform a compression test.
Electronic ignition makes a mechanic lazy about things like ballast resistors, capacitors and coil saturation time.
Change the filters, air and fuel.
Just mentioned was an exhaust restriction. I'd also look at plug condition and gap and perform a compression test.
- Thread starter
- #32
I've been away for a few days, so I'll do my best to answer all the questions I can this early in the morning. I'll be traveling for work the next few days through the weekend and won't be able to work on it until next week.
- Exhaust: I do know that it's not restricted, it's all been replaced right after I got it. My neighbor was having a passive aggressive disagreement with me by leaving his squeaky dogs outside all night keeping us up. So I decided that it was a great time to redo the exhaust and just happened to leave the muffler off...parked it in such a way that exhaust exit was directly pointed at his window every morning when I left for the gym at 4:30
- Filters: I've also changed those as well about a month ago before I put it on the road for the summer
- Timing, tune up, other related items: I cleaned off the plugs a while back until I could sit down with all the part numbers for a full tune up and never got back to it. I'm getting all of that ordered as we speak and will check timing, etc. after everything has been done. I have not checked timing since I've had it.
- Throttle position: The pedal was to the floor when I tried for top speed that day. When I rebuilt the carb I had to readjust the throttle cable and made sure that it was able to open/close without issue and had enough stroke from the cable to open all the way. It is, however an aftermarket Weber and I will get a picture posted as soon as the sun comes up this morning and I can take one to post. I should have mentioned that earlier when I talked about it.
I hope this answers most or all the questions posted since I've last been able to answer. Thanks again for all the responses and the willingness to help out!
- Exhaust: I do know that it's not restricted, it's all been replaced right after I got it. My neighbor was having a passive aggressive disagreement with me by leaving his squeaky dogs outside all night keeping us up. So I decided that it was a great time to redo the exhaust and just happened to leave the muffler off...parked it in such a way that exhaust exit was directly pointed at his window every morning when I left for the gym at 4:30
- Filters: I've also changed those as well about a month ago before I put it on the road for the summer
- Timing, tune up, other related items: I cleaned off the plugs a while back until I could sit down with all the part numbers for a full tune up and never got back to it. I'm getting all of that ordered as we speak and will check timing, etc. after everything has been done. I have not checked timing since I've had it.
- Throttle position: The pedal was to the floor when I tried for top speed that day. When I rebuilt the carb I had to readjust the throttle cable and made sure that it was able to open/close without issue and had enough stroke from the cable to open all the way. It is, however an aftermarket Weber and I will get a picture posted as soon as the sun comes up this morning and I can take one to post. I should have mentioned that earlier when I talked about it.
I hope this answers most or all the questions posted since I've last been able to answer. Thanks again for all the responses and the willingness to help out!
- Thread starter
- #33
Reviving this thread and shaking the dust off from a few months ago with an update and a question.
So it turns out that @JohnnyC was correct in that it was stuck in 4WD. It appears that the vacuum switch is functioning correctly but my FD cable is frozen with rust. So I'll be on the hunt for another cable if anyone has one in good condition?
So it turns out that @JohnnyC was correct in that it was stuck in 4WD. It appears that the vacuum switch is functioning correctly but my FD cable is frozen with rust. So I'll be on the hunt for another cable if anyone has one in good condition?
fjwagon
SILVER Star
Nice looking criuser. Without a top and the size tires you are running, it should easily do more than 46 mph....if everything is properly working in my opinion. 
I had something similar happen to me many years back. The 2f was only firing with 5 cylinders from what I could tell. I unplugged one sparkplug wire and connected it back until there was no change. When you find the one, check the wire or the spark plug. Or just make sure plugs are seated correctly. And hopefully it's just that simple. This may not be an issue but worth checking.
You don't have to upgrade to electronic ignition if you not have already done so but it could give the the engine a little spunk to it. DUI or OEM will do.
I had something similar happen to me many years back. The 2f was only firing with 5 cylinders from what I could tell. I unplugged one sparkplug wire and connected it back until there was no change. When you find the one, check the wire or the spark plug. Or just make sure plugs are seated correctly. And hopefully it's just that simple. This may not be an issue but worth checking. You don't have to upgrade to electronic ignition if you not have already done so but it could give the the engine a little spunk to it. DUI or OEM will do.
rkymtnflyfisher
Trout Bum
4 HI or 4 LO?
Flip the bezel and you could hit 75mph easy and with a roll bar you could break 80.
That is a clean looking rig so going slow everyone can get a good look at it.
Low speed high rev's is either slipping clutch or having it in low gear.
Have you checked to see if the linkage is working on the hi- low lever to see if it is actually in high range?
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Even if the 4wd cable is frozen/broken, you can still get the truck into 2wd, assuming the vacuum shifter itself is not frozen.
The cable only changes which vacuum tube gets the vacuum from the engine. So assuming the shifter still works , you could simply swap the hoses at the shifter and it would release the front wheel drive.
If that doesn’t work, then the diaphragm may not be working. Or you could have rust/electrolysis in the internal shaft that is stronger than the diaphram’s ability to move it.
The cable only changes which vacuum tube gets the vacuum from the engine. So assuming the shifter still works , you could simply swap the hoses at the shifter and it would release the front wheel drive.
If that doesn’t work, then the diaphragm may not be working. Or you could have rust/electrolysis in the internal shaft that is stronger than the diaphram’s ability to move it.
- Thread starter
- #39
The level under the dash is working it between 4HI and 4LO but the front drive shaft spins no matter what. The FD cable itself is completely gone, the plastic covering is gone and the individual wires have all rusted/spread apart. It sounds like I don’t completely understand the operation of the four wheel drive on it...
I’ve replaced all the rubber hoses and one hard line, the other was clear so I blew it out for good measure. As much as I can understand it I’ve narrowed it down to the cable and vacuum diaphragm, is that correct?
As far as the bezel, it’s right side up isn’t it? I was hoping to avoid that mistake... And thanks for the kind remarks. It’s a great driver and 20 footer, I don’t want something that’s too nice to drive. I’m a firm believer in using my vehicles. My high school car was a 1969 Chevrolet Chevelle that my dad and I restored. I’ve attached a picture of it because everyone likes showing off a little bit, pics or didn’t happen as they say.
I’ve replaced all the rubber hoses and one hard line, the other was clear so I blew it out for good measure. As much as I can understand it I’ve narrowed it down to the cable and vacuum diaphragm, is that correct?
As far as the bezel, it’s right side up isn’t it? I was hoping to avoid that mistake... And thanks for the kind remarks. It’s a great driver and 20 footer, I don’t want something that’s too nice to drive. I’m a firm believer in using my vehicles. My high school car was a 1969 Chevrolet Chevelle that my dad and I restored. I’ve attached a picture of it because everyone likes showing off a little bit, pics or didn’t happen as they say.
middlecalf
SILVER Star
Do you have hubs? If so, you’re front drive shaft will spin whether or not the FD unit on the TC is engaged or not as long as the hubs are turned in. Have you put the rig up on stands to see if the FD is engaged? If it is, you need to stop driving on pavement or any non-slick surface. Switching the hoses on the FD unit like @65swb45 mentioned can at least get you out of 4wd until you figure out the cable issue. You can spin out the hubs with the FD unit engaged as well but in general that’s not a good idea spinning that hardware unloaded, especially at highway speeds.
