alsil Posted September 6, 2001 Author Share Posted September 6, 2001 You know, that's one thing I didn't try, and I had a friend who taught me that when I frist started working on cars. can't believe I didn't think of that. Choke is not even set up yet, it's wide open. also, the engine heats up fast, and it was overheating before. I'm pretty sure it's running VERY lean. But that was before I went through it. who knows now. but I'll try that one tonight, too. Quote Link to comment Share on other sites More sharing options...
alsil Posted September 7, 2001 Author Share Posted September 7, 2001 Ok, I didn't get much time to check anythinglast night, but I did a little. I covered the air horn, and it died. So I messed with the idle mixture a bit. Worked a little, but only until it warmed up fully. Then it died. I think the valves may be too tight. The valvetrain on the passenger side is making a lot of noise, where the other side is not at all. I didn't have time to pull the valve cover on that side, but I would bet something's not right. I'm going to loosen them up and see how it affects it. I am also going to put the vacuum guage on it tonight and maybe a compression test. Man, this stuff kills me. thanks for everyone's help on this. AL Quote Link to comment Share on other sites More sharing options...
Guest John Adkins Posted September 7, 2001 Share Posted September 7, 2001 Alsil, Is the intake you're using have the dual spreadbore/ squarebore carburetor flange? Is the carburetor your using have a squarebore (all throttle bores equal sized?) If so, did you use the squarebore adapter plate under the carb? I've heard of people chasing vaccuum leaks for months because of not using this plate.... Hope this helps.... [ September 07, 2001: Message edited by: John Adkins ] Quote Link to comment Share on other sites More sharing options...
alsil Posted September 7, 2001 Author Share Posted September 7, 2001 No, I'm not using that plate. I'm using an Edelbrock Performer Intake and Performer 1406 Carb. They are a matched pair and they say not to use a spacer on it. I have narrowed the problem down, but I still don't know for sure. I'm trying a few things tonight. You going to the meet tomorrow? Thanks AL Quote Link to comment Share on other sites More sharing options...
Guest John Adkins Posted September 7, 2001 Share Posted September 7, 2001 Maybe the Edelbrock carbs have better sealing at the manifold flange than Holleys? The cases where not using the flange plate caused vaccuum leaks were with Holley carbs.... the vaccuum leak was at the flange where where the opening widens to accept a spread bore carb's larger secondaries....but if you have it narrowed down to something, cool!What do you think it is? Yes, I'll be at the meet tomorrow. Look forward to meeting you guys! [ September 07, 2001: Message edited by: John Adkins ] Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted September 7, 2001 Share Posted September 7, 2001 Another silly question. You do have the firing order as 13726548, and not 15426378. Right. The modern 5.0 has a different firing order than the old ones. Quote Link to comment Share on other sites More sharing options...
alsil Posted September 7, 2001 Author Share Posted September 7, 2001 Yea, I knew about that. I have been building these things for a while. Supposedly it evens out stresses on the crank. I am picking up those spacers today to see if that helps. I figure $10 is a safe bet, and if I wind up pulling a vavle cover and finding that the valves are being held open, I am all set to go. If not, I'm screwed anyway. I've pretty much ruled this out as a minor vacuum leak, I did the old hand over the carb test and it stalled. That means it doesn't have a minor leak, that it is either Ok or running rich. I'll see later on today. I'll tell you all about my results tomorrow in San Leandro. If I can sort this out I'll drive it up there. If not, I guess I'm in my wife's car. Thanks for all the suggestions! You guys have really helped. Al Quote Link to comment Share on other sites More sharing options...
blueovalz Posted September 7, 2001 Share Posted September 7, 2001 Am I wrong here in thinking than anything mechanical (valve train, firing order, etc) is going to make the engine run bad regardless of the operating temp, unless of course you are running little to no lash with solid lifters). This still sounds like an A/F mixture problem. Be sure to check (or replace) the power valve. A broke diaphram on this $10 part will dump gas into the carb with little evidence of this happening. Quote Link to comment Share on other sites More sharing options...
alsil Posted September 7, 2001 Author Share Posted September 7, 2001 That happens on Holleys, I don't remember that ever happening on an Edelbrock, that uses a plunger for an accellerator pump. In fact, the plunger is below the outlet in the carb, and in it's own bowl, seperate from the bowls and venturi by about 1/4" of aluminum. I'm suprised more of you guys don't use these carbs, I have one on my truck that I installed 2 years ago, set the jets and idle mixture and haven't messed with it since. The Holleys I used to race with needed constant adjustment. I finally gave up on them after about 1.5 years because I couldn't get a consistant setup out of it. Switched to an Edelbrock, set it once, never had to mess with it again. My 1/4's were consistantly within .2-.3 of each other, while the Holley gave me variations of .5-1. I had 4 holleys, so I know it wasn't just a messed up carb. I used 2 600's(1850), a 750 (3310), and a 650 (marine). The only one that was close was the Marine carb. Don't know why that is. Anyway, you may be right, I'm exploring all options. In fact, I have a call in at Edelbrock. We'll see how this all pans out. the only thing that makes sense to me is that the valves are tight, because as the engine heats up, the metal expands, and the seal might not be as good. You never know! Thanks AL Quote Link to comment Share on other sites More sharing options...
pparaska Posted September 8, 2001 Share Posted September 8, 2001 Al, I'm wondering about the valves at this point. Can't you change that F!rd design to something adjustable for the rocker arms? I always hated that non-adjustable rocker thing on the F!rds. How about Posi-locks or something? I guess you might want to look at the rocker arm geometry also. But why would this have changed if it was all together like that before? Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted September 8, 2001 Share Posted September 8, 2001 Pete, there are plenty of adjustable rockers out there for Fords. Nice not to have to mess with the clearances once they're set right with shims though Quote Link to comment Share on other sites More sharing options...
alsil Posted September 10, 2001 Author Share Posted September 10, 2001 Well, it was a good try, but the valves are not the problem. I didn't have a lot of time on Friday, so I messed with a few things, and figured I'd try out my $10 investment of the spacers. Well, didn't make a difference. It would idle a bit better (because of the milder lift of the cam) but it still did the same thing. I had an idea. Maybe my carb is leaking gas in the intake somewhere. My jetting is pretty standard, I know I probably need to lean it out, but here's the deal. I drove it a bit Saturday. At first, it ran fine, a little rough, but fine. As it got warmer, it would start to miss. Then it got WARM. It stumbled and stalled 6 TIMES!! it even backfired. Now, if there's a vacuum leak, seems to me, it would be more consistant, and wouldn't back fire out the exhaust, but out the carb (lean pop). and I had to keep it up in the revs to keep it from stalling. Al the while, I smelled gas bigtime. I am going to try and swap the carb from my truck in (same exact model) and try that out. If that works, I know my carb is defective. If not, I'm going to mess with jet/rod combos until I get close. Does this all sound reasonable? Or am I barking up the wrong tree? The reason I was thinging this, is that I had an old Holley (yes another messed up Holley story) that dumped gas into the intake BIGTIME because of a cracked metereing body (don't ask me how that happened!) So it was blowing tons of smoke and I didn't even have it running more than 15 seconds. Pulled the carb and a puddle was in the base of the intake (OUCH!) So what I'm going to do is run the Z for about 5 mintues or so, pull the carb, and see if there's puddling. If there is, I'll swap the other over, try the same thing. If it doesn't do it, then I'll check the other to see where it could possibly be leaking. I look at it this way, I doesn't cost anything but gas, so why not. Wish me luck. Quote Link to comment Share on other sites More sharing options...
Guest John Adkins Posted September 10, 2001 Share Posted September 10, 2001 Al, Could it be vapor lock? Is the fuel line running close to the exhaust anywhere? Maybe it's starving for fuel as the exhaust heats up the fuel line and gets a vapor lock. Just another theory..... Quote Link to comment Share on other sites More sharing options...
alsil Posted September 10, 2001 Author Share Posted September 10, 2001 The fuel line is nowhere near the exhaust, and I have an electric pump. Besides, I think it would probably lean pop in that case. But thanks for the idea. AL Quote Link to comment Share on other sites More sharing options...
Modern Motorsports Ltd Posted September 10, 2001 Share Posted September 10, 2001 Alsil, are you sure timing (mechanical and vaccum) are in proper range? On cold start is it ee choke kicked in and your rpm's higher? Have you played with idle screws to see how your vaccuum varies etc to know idle is alright when cold? (as I assume you can't set it hot). Does altering your timing when running make no difference? ie. you think it's at 12 degrees but if at -2 or similar it might fire up cold but as rpm's drop and it warms up it'd be less and less happy with engine speed dropping? Your hesitation off idle you describe is either timing or fuel. I did have a bad 1406 carb once with a numb idle screw. You mentioned another motor from which you could try that carb? After checking vaccuum/timing/plugs (when it's stalling itself I'd pull a plug right after) you may want to install your 1406 on the OTHER vehicle to see if it runs fine on that one. good luck Quote Link to comment Share on other sites More sharing options...
alsil Posted September 10, 2001 Author Share Posted September 10, 2001 So far, I have no vacuum advance because I haven't even got this running enough to get it set up right. I can let the car warm up, and I can get a decent idle as long as I don't drive it. It will idle for about 15 minutes before it starts to get rough. I haven't even set up the choke yet. All the vacuum ports (timing, PCV, etc...) are plugged right now. The timing is set at 12 degress, and I have checked that my advance is working. It does the typical things when I change the timing, advnace makes it quicker, retard makes it slower. I'm sure both the idle screws work on mine, because they BOTH make a difference when I adjust them. Like I said, idle seems to work fine for a while. I'm going to swap the carbs tomorrow, and see what that does. I have had no time since Thursday to really mess with this car. Busy weekend. But hopefully tomorrow I can dive into this. I'm also picking up a tuning kit for the carb tomorrow, just in case the other carb works. Then I can see how I need to set it up. Al Quote Link to comment Share on other sites More sharing options...
Modern Motorsports Ltd Posted September 10, 2001 Share Posted September 10, 2001 Have you tired it with the choke wired wide open? or altering choke at all? are the plugs loaded up with fuel? timing sounds fine so IMO it's loaded up with fuel and stumbling. I'm glad both idle screws are responsive as that was a PITA for me. PS forgot to mention before I agree with Pete on using water/spray to check for vaccuum leaks....ether or propane etc can be used but obviously have their own risks associated with them! Quote Link to comment Share on other sites More sharing options...
alsil Posted September 10, 2001 Author Share Posted September 10, 2001 The choke is wide open so far. I closed the choke and the engine died instantly. Also, another clue is that if I let the engine sit for 5 minutes, it will run again smooth for a minute. I think is HAS to be loading up. I'll see. AL Quote Link to comment Share on other sites More sharing options...
Guest John Adkins Posted September 10, 2001 Share Posted September 10, 2001 float level too high? needle & seat stuck open (dirt)? Quote Link to comment Share on other sites More sharing options...
alsil Posted September 10, 2001 Author Share Posted September 10, 2001 Nope, checked that. Brand new lines, HUGE filter, clean gas tank. no gas leaking into the venturi. But you never know. Al Quote Link to comment Share on other sites More sharing options...
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