Johnvee's 40 Thread
- Thread starter JohnVee
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Parts are everywhere for a Vortec 
I'd agree with Johnny on this one in that you are having an issue with tank pressure. Once you drilled the cap it changed that and I am guessing that the carb was set up with that back pressure in the tank. Once you releived that pressure it changed the carb set up. I know that it should not matter considering how a float valve operates, but it still occurs.
Personally I love fuel injection as I spent many an evening setting up carbs on my bikes and Austin Healys and do not miss it at all. Adding throttle body injection to your 350 is also not all that hard, just takes time and money. Good luck with it John, hope it is am easy fix for you.
You really want to have some fun, set up a few carbs on 2 stoke RC helicoper motors that run on nitromethane. Now that is fun
I'd agree with Johnny on this one in that you are having an issue with tank pressure. Once you drilled the cap it changed that and I am guessing that the carb was set up with that back pressure in the tank. Once you releived that pressure it changed the carb set up. I know that it should not matter considering how a float valve operates, but it still occurs.
Personally I love fuel injection as I spent many an evening setting up carbs on my bikes and Austin Healys and do not miss it at all. Adding throttle body injection to your 350 is also not all that hard, just takes time and money. Good luck with it John, hope it is am easy fix for you.
You really want to have some fun, set up a few carbs on 2 stoke RC helicoper motors that run on nitromethane. Now that is fun
Find out what fuel pressure your carb is looking for (manufacturer spec) and confirm that's what you have in the system. May need to install a FPR once there's no back pressure in the tank anymore.
R
R
- Thread starter
- #64
Stan,
I just picked up a new vented gas cap and will run with that to see if the RPM issue gets resolved. I wanted to run the drilled cap first to eliminate the tank pressure and make damn sure my drain plug wasn't gonna leak. Next step is non-drilled cap. I couldn't find a torque value for a tank drain plug so I used Seal All and torqued it Goot-Und-Tite. The drain is kinda useless as I have to remove the PS exhaust to access it so it might just have to get (JB)welded up after I get the evap stuff installed (I'd love to redesign the exhaust system, though). Plus it seems to spill a lot of fuel into the cab due to the way the tank is mounted and the nature of liquid flowing over threads. Much better to just drain from the fuel pump line.
I know nothing about TBI. Perhaps I should research. You got any good links to send me?
--john
I just picked up a new vented gas cap and will run with that to see if the RPM issue gets resolved. I wanted to run the drilled cap first to eliminate the tank pressure and make damn sure my drain plug wasn't gonna leak. Next step is non-drilled cap. I couldn't find a torque value for a tank drain plug so I used Seal All and torqued it Goot-Und-Tite. The drain is kinda useless as I have to remove the PS exhaust to access it so it might just have to get (JB)welded up after I get the evap stuff installed (I'd love to redesign the exhaust system, though). Plus it seems to spill a lot of fuel into the cab due to the way the tank is mounted and the nature of liquid flowing over threads. Much better to just drain from the fuel pump line.
I know nothing about TBI. Perhaps I should research. You got any good links to send me?
--john
- Thread starter
- #65
Find out what fuel pressure your carb is looking for (manufacturer spec) and confirm that's what you have in the system. May need to install a FPR once there's no back pressure in the tank anymore.
FPR = CISCO????
Good idea. See above about going back to a regular vented cap. But this will matter again once the evap stuff is installed. Thanks. And, yes, Fuel Pressure Regulator.
--john
- Thread starter
- #66
And why?
Just a personal preference on that kind of rig. They both can be tuned for power/mileage/TQ/ etc..... really it doesn't matter as long as you find the right one for what you want.
John, I do not have any links handy but Edlebrock, Holly and several others make complete EFI systems to bolt on a 350. A big plus of this system is performance on off camber situations where a carb starts to have issues. Take a look at Summit and Jegs, they both probably carry several manufacturer's systems.
Have read good things about this one, and the FAST system:
http://www.summitracing.com/parts/hly-550-400/overview/
FAST:
http://www.summitracing.com/parts/fst-30226-kit/overview/
R
http://www.summitracing.com/parts/hly-550-400/overview/
FAST:
http://www.summitracing.com/parts/fst-30226-kit/overview/
R- Thread starter
- #71
Removed, cleaned and refurb'd the removable dash knobs. Still have to do the cabled controls. There was no paint left in the knob lettering so I think they turned out great. I'd recommend finding a true red pen instead of the "pretty close pink" I had to use. Got the idea and info from here:
https://forum.ih8mud.com/40-55-series-tech/267328-dash-knob-refurbish-how.html
https://forum.ih8mud.com/40-55-series-tech/267328-dash-knob-refurbish-how.html
I think I bookmarked that thread 4 years ago and still haven't spent the time. Nice job!
Just a personal preference on that kind of rig. They both can be tuned for power/mileage/TQ/ etc….. really it doesn't matter as long as you find the right one for what you want.
I am a huge fan of the Quadrajet. They are very simple to repair, you can get a great video on how to rebuild them. People who trash talk them don't want to learn how to work on them. Holly is better for racing but for hills, the Quadra-Bog.
EFI of any kind will out perform any carburetor on a steep hill but a Quadra jet works better than 99 percent of the carbs out there on a hill - especially one that is dialed in and working perfectly. They work really well off road. Not as good as EFI, but really well.
I might run TBI from HOWE on my next rig but that means carrying along a whole bin of spare parts instead of just a small assortment in the glove box. There is little or nothing on a Q-Jet that will leave you stranded or dead in the water if you are mechanically inclined and have an inexpensive rebuild kit with you.
A bad tank of gas, driving under water or just plain and simple bad luck means your dead in the water with HEI unless you have a lot of spares and a code reader. But for most people, fool infection is probably the best choice overall. I've seen TBI and TPI vehicles with complex to diagnose problems in the shop much less on the trail.
this is just my .02cents, not facts.
- Thread starter
- #74
^^^
The Holley has treated me well for the limited off camber/slopes I've been willing to subject the 40 to. It's usually my bad ankles and touchy go pedal that have stopped me. That said, I've got snowdoggyyz's QJet on the way (thanks a ton!). I plan on learning to rebuild on the Holley since I'm used to how it runs and will know the difference if I screw up, then comes the QJet.
I know that FI is a great thing, but I specifically bought a carb vehicle to learn how to work on it and I'm not building a purpose-built truck yet so it'll stay as is for now. Besides, The 80 has seen 5x more dirt than the 40 this year!
--john
The Holley has treated me well for the limited off camber/slopes I've been willing to subject the 40 to. It's usually my bad ankles and touchy go pedal that have stopped me. That said, I've got snowdoggyyz's QJet on the way (thanks a ton!). I plan on learning to rebuild on the Holley since I'm used to how it runs and will know the difference if I screw up, then comes the QJet.
I know that FI is a great thing, but I specifically bought a carb vehicle to learn how to work on it and I'm not building a purpose-built truck yet so it'll stay as is for now. Besides, The 80 has seen 5x more dirt than the 40 this year!
--john
I have played with carbs all my life, starting with minin bikes and go carts to bikes, Austin Healys, RC helicopters and planes, boats. I have had mny fill of carbs I have embraced EFI and all the benefits. Sure, both will let you down at some point. If I have to I will play with a carb.
I have embraced EFI and all the benefits. Sure, both will let you down at some point. If I have to I will play with a carb.
We were trying to get john vee's 40 running today. It needed and oil change but we did not have enough oil to match what came out. Just about 6 gal of gas from the oil plug.
The good thing is that inside the engine is very clean. The bad thing is that the inside the engine is very clean.
The good thing is that inside the engine is very clean. The bad thing is that the inside the engine is very clean.
What ceases the gas in the oil?
Meatball
Meatball
- Thread starter
- #79
So here's the thing - carb was leaking from baseplate gaskets in December. Ran fine until then. It sat with about 2-3 gallons of gas until 3 weeks ago when the rebuilt carb went on. Still leaked and I never even idled it for over 5 seconds. Left it alone and bought parts.
Jump to this past weekend. Pulled carb and repaired. Got it running leak free Saturday afternoon. Idled fine for less than a minute. Didnt get to the point of adjusting floats. Ran out of gas. Put approx 2-2.5g of gas in. Dead battery. Charged overnight while removed from vehicle. Tried again Sunday morning. Hydro locked. Pulled spark plugs and drained fuel from 4 cylinders. Removed fuel feed line from carb. Unhooked battery and left it alone. Meant to change oil and forgot.
Jump to today. Fresh battery. Pulled plugs and drained fuel. Cranked engine with electric unhooked and cleared more fuel. Reinstalled electric. Wouldn't start. Rewired fuel pump to on off switch and filled carb. Adjusted floats. Wouldn't start. Battery weak so jumped it. Starts. Giant cloud of white smoke. RPM at 1k to idle. Some Venezuelan guy pulls PCV valve and dodges a spray of rather flammable liquid. Shut off engine. Remembered to drain oil. Luckily, my drain pan is missing so I use a large bucket with a 24+ quart capacity. Lucky because over 6 gallons of fluid came out. That means about 4.5 gallons of gas.
Not sure when, where and how that amount of fuel got there. The numbers are admittedly estimates, except for what's clearly in the bucket now.
Now that I've typed all that on my phone I think I'm seeing it, IF my pump is bad.
The plan is to keep the drain open overnight and then fill with oil tomorrow. Get it running and warm it for a while and drive. Change oil again. Hope for the best. Might as well replace the pump and finally wire in a relay. And hope that I don't explode.
Jump to this past weekend. Pulled carb and repaired. Got it running leak free Saturday afternoon. Idled fine for less than a minute. Didnt get to the point of adjusting floats. Ran out of gas. Put approx 2-2.5g of gas in. Dead battery. Charged overnight while removed from vehicle. Tried again Sunday morning. Hydro locked. Pulled spark plugs and drained fuel from 4 cylinders. Removed fuel feed line from carb. Unhooked battery and left it alone. Meant to change oil and forgot.
Jump to today. Fresh battery. Pulled plugs and drained fuel. Cranked engine with electric unhooked and cleared more fuel. Reinstalled electric. Wouldn't start. Rewired fuel pump to on off switch and filled carb. Adjusted floats. Wouldn't start. Battery weak so jumped it. Starts. Giant cloud of white smoke. RPM at 1k to idle. Some Venezuelan guy pulls PCV valve and dodges a spray of rather flammable liquid. Shut off engine. Remembered to drain oil. Luckily, my drain pan is missing so I use a large bucket with a 24+ quart capacity. Lucky because over 6 gallons of fluid came out. That means about 4.5 gallons of gas.
Not sure when, where and how that amount of fuel got there. The numbers are admittedly estimates, except for what's clearly in the bucket now.
Now that I've typed all that on my phone I think I'm seeing it, IF my pump is bad.
The plan is to keep the drain open overnight and then fill with oil tomorrow. Get it running and warm it for a while and drive. Change oil again. Hope for the best. Might as well replace the pump and finally wire in a relay. And hope that I don't explode.
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So. You do have a pump on side of block then ? If do it is bad from the sounds of it or if you have an electric pump it is pumping all the time even when off. It is pouring it thru the carb. It is easy to figure out either way.