Hey all,

I've got a 1986 F150 with a 351w HO and a C6 trans, almost everything under the hood is original save a few gaskets and vacuum lines.

On a recent off-roading trip I noticed a strong fuel smell coming from the engine and discovered that fuel was dripping from the carb's accelerator pump cover and pooling in the intake manifold. Made it home with no issues, but was sure glad I had a fire extinguisher mounted next to me.
Right now I am debating fully rebuilding the original 4180c that's on there, which I have never done before, or buying a refurbished carb and putting that on there. It's my daily driver and only car, so the ease of bolting a new carb on sounds attractive just to get me back on the road. If I went that route I would hang on to the original carb and eventually rebuild it at my leisure. I am currently in college and living in student housing so the only place I would be able to do a rebuild right now would likely be at my desk, and I don't know if I really want my dorm to smell like gas and carb cleaner for the rest of the semester. Unfortunately all the carburetor rebuilders I found around me seem to have questionable reviews or are very far away.

I'm still relatively new to working on cars so I was hoping to get some advice from the experts here. Is rebuilding a carburetor easier than I would expect? Do you think I would need a more suitable work space than a dorm room? I'm a pretty quick learner and so far I've been able to learn how to do 90% of the maintenance on the truck myself just from youtube and the Haynes manual. I'm pretty sure I have all the basic wrenches and screwdrivers I would need, but are there any other tools/ gear I would need that I might not be expecting?

If I went the replacement route, which carbs should I look for as an easy replacement? Are there certain criteria the carburetor should have to make it an easier and more seamless swap? Right now I still have all the emissions stuff hooked up and would rather not have to mess with it. I am currently going to school in CA, but the truck is registered in MA so passing emissions is not my highest priority since I am exempt in MA and do not plan on ever registering it in CA. I am mostly using the truck as a daily driver and occasional weekend off-roader.

Thanks for the help!

 

I would stick with the original carb. Since you are just trying to get by, go to a local autoparts store,, they should have display with a bunch of Mr Gasket parts hanging on it. They should have a accelerator pump diaphragm on the rack. If you can find one, I would just pull the carb, replace the accelerator pump, and put it back on the engine. That should solve the leak.

 

Make sure it's a gasket and not a bushing that is leaking. That is a separate kit.
the pressed in "sight fills" also like to leak and some good epoxy can stop that.

 

As much as it pains me to admit, I must agree with Dave. If the carb had been performing adequately otherwise, I'd simply fix the leak and move on. Follow my personal motto and don't do any more work than necessary.

If you do feel compelled to "rebuild" the carb, may I suggest hiring an MMA fighter with anger management problems? No, he won't actually be doing the rebuild. You'll be paying him to beat the crap out of you for wanting to tear apart a basically good carb with a relatively minor external problem.

After you recover (I tried to warn you), and you still want to do a "rebuild", may I suggest purchasing a remanufactured unit instead? The typical home "rebuild" (note the annoying way I keep using quotation marks) is little more than a half-hearted cleaning, new gaskets, and setting the float level. A professional rebuild (no quotes) is so much more, including taking care of worn shaft bushings and doing a flow test. I'm not saying a home "rebuild" (there he goes again with the quotes!) is pointless, but it doesn't fix most carb problems.

Considering your workspace situation (a college dorm room in the People's Republic of California, angsty SJW roommate playing Nickelback on loop), I'd leave well enough alone and just fix the leak.

If you do want to go the reman route, I got one from Autoline in Canada. I am very pleased with it:

https://autoline.ca/

They don't appear to sell retail. I think I got mine from Rockauto. Not cheap, but you get what you pay for.

 

Well my opinion is
You would be further ahead buying a new 4160/4150 or edelbrock or whatever new actually than buying a reman unless you need to have that carb for emissions or factory resto.
Local shop wanted about 250 to rebuild mine. Rockauto wants 465~ for a reman +core charge, which I think Karl is subjected to?
my new 4160 was under 400, but I think they have gone up in price in the last 3 months.
I'm just saying if it isn't required there are more economical options for replacement minus doing the rebuild yourself which would be under 100 for the kits.
The 1 place my 4180 never leaked from was the accelerator pump. but it leaked in about 3 other places over the time I owned it.

 

Hahaha thanks for the advice. I didn't realize the accelerator pump diaphragm was so easy to replace, I'm still pretty new to this so when I saw the fuel leaking my mind went straight to the only thing it knew which was rebuild. I guess I kinda thought I'd have to pull the whole thing apart to get to it anyways, but I watched a couple videos and see how it works now- learning more as I go. Otherwise it's been running great so far so I'll try to just replace the diaphragm this weekend.

I'm trying to find one of those Holley green ethanol-proof diaphragms locally, but if I can't it looks like any standard 30cc diaphragm would fit the application. Am I correct in that estimate? I haven't been able to find clear fitment info on O'Reilly or auto zone.

Thanks again for all the help! This job seems a lot less daunting now, I'll let you know how it goes.

 

Yeah, I see what you mean. I think I'll just replace the diaphragm for now, I originally didn't realize how simple it was to just do that. I'd definitely rather buy a solid quality new carburetor because I actually wanted one than be forced by circumstance to buy a cheaper alternative. Thanks for the heads up!

 

Just for future reference. I have a 351W and 4 speed. I had a carb issue last year and got tired of messing with it. I bought one of the Chinese knockoffs off Amazon and it worked beautifully right out of the box. It was $85. I put it on, hooked up the fuel and linkage, and it fired right up and idled great. I adjusted the choke and the carb and it’s working great to this day. I kept the original. Just giving my personal experience for what it’s worth.

 

I haven't seen a 4 barrel knock-off carb. That is what he has, a 4 barrel made for Ford by Holley.

 

You can get a aftermarket carb, but it won't have all the hook-ups for all the emissions stuff you have. You said it's all original. You can go with a aftermarket carb and get rid of some of the emissions stuff, but it turns into a project with some research involved.

 

You are correct. It is a 2 barrel.

 

Well, I pulled the carburetor and replaced the diaphragm this weekend and it worked great. I discovered the previous owner had adjusted the linkage so that the diaphragm was constantly fully depressed, I readjusted that back to the recommended setting and the truck is running great now, no more leaking and much more responsive off the line.

Thanks for all the tips, you guys saves me a bunch of time and money!

 

Why does everyone crap on Nickleback?

Also, l think l win the quotations battle.
"Checkmate" was quoting you're entire post so l could ask a stupid, unrelated and completely irrelevant question.
The ball is now in your court, sir.

(Please note the gratuitous addition of a forced mixed-metaphor... the cherry on top..
DAM...
hat trick!
For my next trick, I'll be writing completely in haiku.