Ok, here's the deal. I'm sure all of you have read my posts a thousand times. I have a 1986 F-250 HD 4x4 with a 351W, 351 Performer intake, Holley 750 4bbl carb....so my starters keep going bad. It's not the flywheel, that's in good codition. I finally decide it has to be because my headers are so close and keep burning it out, the solenoid. Anyhow, I buy the wrap-around heat shield today at Indy Auto on Rt. 1 in Peabody. Truck is running fine up to now. I get the part, back on 95 South, heading back to Wakefield. Make it to Wakefield exit, no problems. Come down the ramp, all of a sudden, BAM! Truck starts boggin out like it's being either flooded or starved of fuel. I make it to a parking lot by keping one foot on brake, one on gas making sure it doesn't go below 2000 rpms or it will die out. Park truck, don't even have to turn key to shut it off, it just dies. I take off air cleaner and look into carb...smoke of unburnt fuel whisping out. Look closer at side right near throttle arm going into carb, little wet so I dry it off. Gas leaks from here, puddles on intake manifold. SO what the heck is going on? Are my floats messed up? Or is there a gasket that sits on the throttle arm (I'm guessing that's what it is) and it has either slipped off or warn away. I finally get truck going again but it's bogging out. I drive back to work and the whole way as I have to slow down for cars in front of me, I have my foot on gas and brake, and when I stop and keep foot on gas and brake to keep it from dying out, it pours smoke from exhaust....what the heck is going onnn???? HELP!!! Any quick fixes to get me home??? Oh man this hurts!

Ryan
1986 F-250 HD 4x4
4.10 gears, C-6 tranny
351W, Edelbrock 351 Performer aluminum intake
Holley 750 4bbl carb
Extreme 4x4 camshaft
3" body lift by Warn

 

From symptoms it souunds like she jumped time on the timing chain. Lack of power, Having to keep your foot in it at stop, smoke out the back (black????)


I wouldn't think a miss adjusted float would give you the symptoms your describing.

Look for timing problems. Check your timing with your light. I'll bet it's retarded at least 10-15 deg.

Larry

 

Most definately not the timing...I've played around with that (rotating the distributor) found just where it should be for peak performance...I don't use a light, don't even have one...I just do it to sound and feel of the engine under strain like on the highway, and that was fine up until today. I really think it's the carb, cause I can visibly see gas leaking from what I believe is the throttle arm going into the carb. I have spoken to a friend of mine here who says it sounds like floats are out of wack...I dunno...I need help, this is (orat least was) my dailey driver....I need her back and running good, but hope to god it's not a big fix up thing.....and by the way, no, the smoke is white, smells like partially unburnt gas. Somehow there is something wrong in the carb, I'm almost sure...some kind of leak, maybe floats out of wack, maybe a gasket or rubber something or other missing or not in place right...never had this prob before, what's going on, I need my baby!!

 

Could be the floats, bad needle valve or seat, or maybe even the power valve if it blew big time, or came unseated somehow.

 

ok, so if that's the case, what do I need to do? can I just adjust the floats? they're spring balanced, or loaded, or something, right? I'm not gonna need a new carb, am I? I'm broke with all I put into this truck, I can't afford anything else!

 

Your in luck, you have a holley carb. You should have a large screw and nut combination on the top of each float bowel. Take the screw out, and then using the nut, unscrew the needle assembly all the way out. There is a little o-ring installed around the assembly and hopefully it didn't tear. If it did, get a new one from a speed shop. Anyway, look down in the middle of the assembly and see if there is a piece of dirt under the needle valve. Do this for both bowels. All it takes is one little chunk of dirt. Do you have a good fuel filter installed? Even when re-installing a fuel line, a little chunk of rubber can come off the hose and cause this to happen. When you re-install the needle assembly, make sure you put a little oil on the o-ring so it will go in without getting torn up. Try to install them close to the depth they were originally. Then take out the sight plug screw and put a rag underneath the hole. Start the truck and run around to see if any fuel is coming out of the sight hole. If it is coming out pretty good, shut off the truck and lower the needle assembly and try again till you get the fuel level at the bottom of both of the sight plug holes.

 

Welcome to the land of Holley carbs. Did the truck happen to backfire just before it started running rough. If it did then it probably blew a power valve you have to take the front fuel bowl and jet plate off to replace this. the gaskets on these are a pain to clean up. I recommend using no stick cooking spray on the gaskets when you replace them so when you have to take them apart again they don't stck near as bad. And it is a Holley so you will get to take it apart again. Before you take the carb apart remove the sight plugs and see if one of them runs fuel out while the truck is running if it does then there is a float /needle seat issue. and you still have to take the bowls off to replace the floats(s). God iam glad they finally went to fuel injection the last of the carbs where a joke and Holley has been sold so many times I don't think they know how to build a carb anymore. Had a brand new out the box that the needle and seat wasn't installed correctly.

 

the hrottle shaft seal might have gone bad, I had this happen on a Holley/fomoco carb, same symptom puddle of gas under throttle shaft on intake. Blow a little bit of ether around where the fuel is leaking out and seee if you have a vaccum leak there.

Kind of a guess, but tryin to help

John

 

I'm actually thinking of caving in and just buying the Edelbrock 750 4bbl (square flange I think) manual choke. Am I right in assuming a manual choke is suck like where you have to pump your gas once or twice to feed the beast, and an electric choke is one where once the key is turned, it automatically sends gas? I'm really not to knowledgable of carbs, and it seems like there's so many applications with Holley, Edelbrock, Ford OEM, and on and on...

Anyhow, It would probably be wise to get the Edelbrock carb, seeing as my aluminum intake is an Edelbrock Performer...just to keep parts the same...

Ryan
1986 F-250 HD 4x4
4.10 gears, C-6 tranny
351W, Edelbrock 351 Performer aluminum intake
Holley 750 4bbl carb
Extreme 4x4 camshaft
Flowmaster 30 series true dual exhaust w/ custom long headers
3" body lift by Warn

 

It's your money, but before I spent $250-300 on an Edelbrock, I'd spend $13 on a book and learn about my perfectly good Holley...

 

For your application, you want to put on a 600-650 Edelbrock. Unless you have the cam and heads, the 750 is way too much for your 351W. The electric choke simple runs off a power supply to shut the butterfly and let your engine run rich until it warms up a bit. The manual choke allows you to manually open or close the butterfly to adjust how your carb is running. I would suggest the electric.

By the way, I would also guess a bolwon power valve on your old carb.

'82 F150 2WD w/351W (orig 300 I6)
Slik

 

By the way, if you are tuning by ear... you're missing a lot. You can adjust to "peak" performance pretty close, but you are also adjusting to cover up other conditions like vacuum leaks or poorly adjust carb, etc. For example, you may only have your timing set at 5 degrees BTDC for your ear, but your peak performance should be around 14-16 degrees BTDC and some other condition is causing you to retard the timing. If you want to keep your truck running good, then get a timing light and see what your truck is really doing.

'82 F150 2WD w/351W (orig 300 I6)
Slik

 

Ah yes! Been there also. Black smoke out the tailpipe. Puddle of gas on the intake. Fuel just pouring down the inside. Total engine gaswash. I had to replace the carb as well as changing the oil and plugs.

Jakegypsum // Ford fleet, soup to nuts.

 

Guys, thanks alot for all the help, but I do think I'm just gonna try to pick up a new edelbrock to sit atop my 351 Performer intake. As for checking timing with a light, yes, this may work great for stock motors, but doesn't everything change when you add high temp plugs and twin core wires, performance cam, aluminum intake, etc...? I mean, it may not, I may be off on this, but, ohh I dunno...yeah, I think I'll just get the new carb....do these come preset so you basically have you just have to bolt it on and maybe adjust the carb? or do you still have to mess with floats, needles, jets, etc? And no, it is not black smoke..I mean, it is sometimes grey, idling, but for the most part it's whitish and smells of unburnt fuel......

 

Well folks, this morning I caved in cause I wanted my baby to be running smooth again. I bought a new Edelbrock 600 cfm 4bbl electric choke carb. My problems seem to be all gone, I hope they stay that way, she's running great again, and I'll notify you all of any updates. Downsizing from the 750 to the 600 DEFINATELY is saving me gas money, I gained another 2 or so mpg, now up to 13 or so. Thanks again, guys!

Ryan
1986 F-250 HD 4x4
4,10 gears, C-6 tranny
351W, Edelbrock 351 Performer series aluminum intake
*NEW* Edelbrock Performer series 600 cfm 4bbl
Flowmaster 30 series true dual exhaust w/ custom long headers
3" body lift by Warn