'87 Bronco 351w Carb Issues

[MonsterTrukz7]

I have a 1987 Bronco with a 351W that is all stock. I am having some carb issues. When shut off, the carb percilates fuel (fuel from the carb drips into the hot intake manifold and evaporates). I get horrible gas miliege, about 8 mpg, i know this is common with broncos though. The worst of the problems is on start up. After having to pump the gas quite a few times to get it started, it will run on high idle just fine to warm up, once i hit the gas to drive away it kicks down as it should. but when stopped at stop lights when the engine is still cold, it will just die. i have to put it in nuetral and put my foot on the gas to keep the rmp's above 1000 to let it warm up more and keep it running. any suggestions as to how to solve this problem? i have been thinking about switching carbs to an edelbrock but i dont know if this is really wise. if i do, i have a feeling that none of the smog emission lines will hook onto the new carb. if anyone has some insight on my issue please let me know. thanks!

 

[Broncoholics]

Why not go manual choke? I did this in an older rig I had with same problem.

Drilled a hole in the firewall, slipped the linkage through and attached a pull **** to the dash, the other end connects to the carb. Then push it in when you know its fully warmed up.

 

[Justshootme84]

Sounds like the accelerator pump&rod are worn out. I had this problem with my original Holley, and suggest replacing the carb, especially if leaking gas. The Edelbrock 1406 (electric choke) is a direct replacement. If you have an auto transmission, the only change is a bracket for the kickdown linkage and rod.

 

[Seabronc]

A manual choke might be the solution to one of your problems, but you seem to have more problems than that can fix. It is very likely that a new carb is in order. You currently have a 4180 Ford on that engine.

Number 1, the dripping is probably caused by too much fuel in the float tank/s. Probably due to a sticking fill valve or mis adjusted float. Most likely sticking and alowing the residual pessure in the fuel lines to over fill the float tank.

Number 2, stalling at lights depends on when that happens. If only durring warm up, then the choke is probably not functioning properly. If all the time then the curb idle is most likely out of adjustment. You could also haave issues with the EGR, which realy makes the engine run like crap if it is not functioning properly.

The issue of a new carb is a very good idea, especially if this is the stock carb I claimed it to be in my first line. Edlebrock carbs have a reputation for better milage. If you need to keep all the emissions stuff, I'm not sure you can with an edlebrock, I happen to be a Holley bigot :lol: . Atleast, you will have to reroute a few lines and adapt a litttle. I switched to a 4160 which means I lost the lines for the float tank vapors. However, I retained all other emissions lines. If your state is realy a stickler for emissions requirements, it is usually "illegal" to have anything but OEM stuff onyour truck, but then who's looking h34r: /emoticons/[email protected] 2x" width="20" height="20" /> . With that engine covered up by the stock intake filter no one would be able to tell what was what underneath. Not sure if it will fit on an Edlebrock carb though .

picture of my 351W with a 4160 installed attached.

Good luck,

>-

 

[Seabronc]

If you decide to go with a 4160, I will talk about that more in a seperate post, I'm sure someone on here can cover the issues with adapting an Edlebrock better than I can. All I can tell you, is that going from a beat up old 4180 plus a few emissions and control items to the 4160 turned a truck that wouldn't move untill it warmed up to a start an go truck.

A different view.

>-

 

[MonsterTrukz7]

Wow! Thanks a lot! the input is really appreciated by everyone. JustShootMe, one question...so you did this exact swap and the 1406 edelbrock was a direct bolt in? no issues with bolt alignment on the intake manifold? how about fuel line pickup? and all the hoses (smog stuff) that currently plug into the stock carb? anything other suggestions would be great. thanks a lot!

 

[broncobust]

Would rebuilding the carb do the trick my 83 does the exact same thing so i bought a rebuild kit.Will this help?

 

[Justshootme84]

Would rebuilding the carb do the trick my 83 does the exact same thing so i bought a rebuild kit.Will this help?

bb, I'll answer your ? first. A rebuild kit may help, but I would get a Holley kit, not the chaeper foreign junk. The gaskets and parts will fit and align better with a Holley kit ($50). Keep in mind that the carb may be so worn out that repair will not help and you must replace it. IF it's the original unit, I would venture that it's beyond repair as mine was. I wasted $50 trying to fix it and still had leaks from the worn body castings.

 

[Justshootme84]

Wow! Thanks a lot! the input is really appreciated by everyone. JustShootMe, one question...so you did this exact swap and the 1406 edelbrock was a direct bolt in? no issues with bolt alignment on the intake manifold? how about fuel line pickup? and all the hoses (smog stuff) that currently plug into the stock carb? anything other suggestions would be great. thanks a lot!

MT, I have the EDL #1405 manual choke on another truck, too. On my 84 Bronco, I went with a reman OEM 4180 Holley for the same reasons as you state.This is the easiest way to go, since all hoses and linkage is the same. I paid $300 from O-Reilly's, Ford wanted $700!!! The EDL 1406 is as close as you can get to a direct bolt-on, with the main diiference being the kickdown rod linkage like stated. IF you need to keep it smog legal, look for a #1400 which is very similar. Half of the emissions control components on my rig no longer work, but they are still hooked up. I re-routed some items when I replaced the intake manifold for an EDL Performer series. Since it only has one vacuum port, I sacrificed cruise control. But you can always reroute a line or two to keep things functional if necessary.

My final bit of advice would be to look at an Edelbrock catalog, or call the tech line at Summit Racing or Jeg's, wherever you might buy a new carb.

 

[Seabronc]

The problem with a rebuild kit verses a remanufactured 4180 is that parts that are not supplied in the kit are most likely worn and that means vacuum leaks thru the throttle plate pivot points. Vacuum leaks will cause poor operation and make it almost if not impossible to get it adjusted properly.

No matter what you go with, check the intake manafold surface where the carb mounts. Mine was slightly eroded by the exhaust gasses thru the EGR and I had to mill it down just a bit to get rid of the vacuum leak it caused.

Good luck,

>-

 

[Justshootme84]

Good points, SeaBronc!!! Vacuum leaks arre a real problem with this carb, and there's a ton of lines going everywhere. I found a major problem with the ported vacuum fitting, which a plastic piece on top of the manifold right in front of the carb. The H.O. air claener housing just touches it, and it can break easily. Since I had a fresh new longblock motor, I scrapped the original intake manifold. I also went to an open element air cleaner, then the Shaker kit. I do plan to swap out the 4180 for the Edelbrock carb in the near future. I still have occaisional stalling fits on cold days, but no gas leaks.

 

[MonsterTrukz7]

Thanks again for everyones help. This has made my decision easy, i think i am going to take the hit in the wallet and buck up for the edelbrock carb. hopefully this will solve my problems that i am having.

 

[grande_guerre]

Quick question for someone, is the carb throttle bracket different on a 351 windsor than on a 302? i did the swap, and am having problems with aligning the bracket and throttle cable.

 

[Seabronc]

Yep, I'm prettty confident that there is a difference. There are several brackets depending on what the manafold carb combination is. If I looked hard in my garage, I might have one for a 351W with stock manafold and Holley carb. If you want, I'll take a look tomorrow.

Good luck,

>-

 

[grande_guerre]

Would that same bracket work for a stock manifold and an edelbrock carb?

 

[Seabronc]

I don't know about that. Basically you need a strait shot from the bracket to the throttle attachment. By strait shot I mean not off at some angle and level. Anything else can cause a bind or prevent the peddle from having full range of operation. I think Justshootme has done this conversion on one of his trucks and probably can tell you if he had to adapt the bracket or what.

When I had a edlebrock performer mounted on my 351, I had to build an adapter to get the bracket in the right alignment.

Good luck,

>-

 

[grande_guerre]

I was told by the sales rep. that i needed this throttle bracket adapter, so i got it, but it is proving to be more trouble than actually helping. Plus it didn't come with any instructions so i dont know how to put it on at all and doubt the sales rep would know the right way to put it on... <_<

 

[Seabronc]

I'll look in my garage today to see if I have a stock bracket.

>-

 

[MonsterTrukz7]

Well I just completed the swap this weekend. Thank you all for your advice, it worked out perfectly. The truck runs much better, doesnt stall, and hopefully I will be getting better fuel milege, I will see once i run this tank dry. For anyone looking to complete this same swap, i used the edelbrock 1406 carb. you also have to get adapters 1483 and 1491. those adapters include the kickdown for automatic transmissions and a throttle lever cable relocator. once I got the carb on, i ran into a few road blocks because of some emission stuff that is on my truck but they were easily overcome. i have come to the conclusion that my truck is a california truck and that is why there is so much emission control stuff on it. anyway...once i get a fuel milege number i will post that.