Low Low Idle
#17
No, it screws into the bottom center of the bowl, you have to take off the throttle section to get to it. One test is to pour some gas into the bowl with the bowl cover off (ENGINE OFF!!) and let it sit for an hour. Fill it to normal fuel level, more or less. If it disappears or level drops significantly, the power valve is leaking. You can also do this with the carb off the engine, it's probably easier.
#18
#19
Here is something I clipped from the MSN Flathead site a long time ago. It is referring to an AN-style fitting copper crush washer, available at most hydraulic stores. I have not found it necessary to use them, but understanding what the potential problem is can help you fix a p.v. that is leaking at the gasket:
"I've mentioned this here before, but the late-style Holley power valve found in just about every new 94 rebuild kit is not designed to correctly fit the 94 carburetor! The correct 'early' power valve has a slightly different gasket base and ports compared to the late valve. The late valve has a radius at the inner corner and the ports are low and square shaped. The early valve has a flat gasket base and round ports set slightly higher in the stem. Using the late valve and kit gasket in a 94 is where all of the trouble comes from. They don't line up, or seal properly. The new valve will work fine with the 1/2" AN crush washer IF you tighten it down properly. You need to 'crush' the washer in order to properly seal due to the radius, obtain the clearance AND to make sure the ports are exposed. With the late valve, install and tighten the valve and AN crush washer, then carefully remove it and check the port openings. You want the top of the ports exposed and showing above the gasket surface. That's all you need. If the valve is tightened sufficiently to clear the well, the ports should be exposed enough to function correctly. Don't be bashful- tighten it up, but don't go overboard. Next check the clearance w/o the base-to-bowl gasket in place. The valve should clear the well. With the early valve, the ports are high enough to where their exposure is not a problem, but you still need to make sure it clears the well..Because the actual machined gasket seat on these late valves is outside the seat area of the 94 bowl section, you now need to seat the stepped, unmachined inner area of the valve (with the radius) to the carb body instead. It's this stem radius and unmachined area inside of the actual outer seat that must now seat to the 94 body. This is why flat washers will not work here. You need to allow for the radius and the unmachined area being used for a seat.
A rolled copper crush washer is ideal for this. Place the copper crush washer, with the open/split side toward this new seat of the valve, against the radius at the bottom of the threaded stem. This will allow the stem's radius to fit into the rolled I.D. of the crush washer and it will form nicely when crushed. Now I'm speaking of a decent body with good, solid threads because you need to tighten the valve sufficiantly to crush the washer. If your carb body has marginal threads, then please beware. You can also use a drop of oil on the valve's threads to help prevent galling when tightening the valve. "
With a little file work you can square up the shaft of the power valve, it works better than the copper crush washers IMO. I use the thin red fiber flat washers that usually come with the rebuild kit.
"I've mentioned this here before, but the late-style Holley power valve found in just about every new 94 rebuild kit is not designed to correctly fit the 94 carburetor! The correct 'early' power valve has a slightly different gasket base and ports compared to the late valve. The late valve has a radius at the inner corner and the ports are low and square shaped. The early valve has a flat gasket base and round ports set slightly higher in the stem. Using the late valve and kit gasket in a 94 is where all of the trouble comes from. They don't line up, or seal properly. The new valve will work fine with the 1/2" AN crush washer IF you tighten it down properly. You need to 'crush' the washer in order to properly seal due to the radius, obtain the clearance AND to make sure the ports are exposed. With the late valve, install and tighten the valve and AN crush washer, then carefully remove it and check the port openings. You want the top of the ports exposed and showing above the gasket surface. That's all you need. If the valve is tightened sufficiently to clear the well, the ports should be exposed enough to function correctly. Don't be bashful- tighten it up, but don't go overboard. Next check the clearance w/o the base-to-bowl gasket in place. The valve should clear the well. With the early valve, the ports are high enough to where their exposure is not a problem, but you still need to make sure it clears the well..Because the actual machined gasket seat on these late valves is outside the seat area of the 94 bowl section, you now need to seat the stepped, unmachined inner area of the valve (with the radius) to the carb body instead. It's this stem radius and unmachined area inside of the actual outer seat that must now seat to the 94 body. This is why flat washers will not work here. You need to allow for the radius and the unmachined area being used for a seat.
A rolled copper crush washer is ideal for this. Place the copper crush washer, with the open/split side toward this new seat of the valve, against the radius at the bottom of the threaded stem. This will allow the stem's radius to fit into the rolled I.D. of the crush washer and it will form nicely when crushed. Now I'm speaking of a decent body with good, solid threads because you need to tighten the valve sufficiantly to crush the washer. If your carb body has marginal threads, then please beware. You can also use a drop of oil on the valve's threads to help prevent galling when tightening the valve. "
With a little file work you can square up the shaft of the power valve, it works better than the copper crush washers IMO. I use the thin red fiber flat washers that usually come with the rebuild kit.
#20
Thanks for all the help, this is really a great forum. After taking the top of carb off I noticed that the throttle plates were not open all the way with the idle stop screw all the way in. I remembered 3MIKE6 wrote that with the idle stop screw all the way in the throttle plates would be open. It ends up the lever that the idle stop screw goes through was bent slightly keeping the top of the lever from resting agaist the choke lever, therefor the position of the idle stop screw was slightly back giving me the low idle. After I bent it back the thing ran fine.
After I let her idle for a while I decided to run down to the gas station to fill her up. It was the first time I drove her in 2 1/2 years & it felt good, she was running great. While waiting for a gas pump to free up for a couple of minutes the engine stalled & would'nt start!! Ends up theres still more crap in my gas tank- the fuel bowl was filled with orange sludge. I sat there for 10 minutes, & had a bunch of people ask questions about my truck, which is always pretty cool, untill my neighbor came to tow me home After taking the tank out the top 2/3 of the inside is totally rusted. I ordered a new one today.
After I let her idle for a while I decided to run down to the gas station to fill her up. It was the first time I drove her in 2 1/2 years & it felt good, she was running great. While waiting for a gas pump to free up for a couple of minutes the engine stalled & would'nt start!! Ends up theres still more crap in my gas tank- the fuel bowl was filled with orange sludge. I sat there for 10 minutes, & had a bunch of people ask questions about my truck, which is always pretty cool, untill my neighbor came to tow me home After taking the tank out the top 2/3 of the inside is totally rusted. I ordered a new one today.
#21
#22
Great you fixed it...I was gonna offer pics of my 94 linkage.
One thing to to do is add an in-line glass fuel filter with a filter cartridge...you can see the "crap" and clear it out before it reaches the carb. Also go ahead and flush or replace the fuel lines and fuel pump...there gonna have leftover stuff in them too.
It's cool to finnaly drive-em....I waited 3-1\2 years.
later, Ed
One thing to to do is add an in-line glass fuel filter with a filter cartridge...you can see the "crap" and clear it out before it reaches the carb. Also go ahead and flush or replace the fuel lines and fuel pump...there gonna have leftover stuff in them too.
It's cool to finnaly drive-em....I waited 3-1\2 years.
later, Ed
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