Valve cover breather and ingition wires

[Walrus_in_SA]

Im a first time early bronco owner (finally) and a novice in the garage and wanted to pose a couple of questions to the brotherhood: I recently had a major tune up done (by a seasoned classic car mechanic) and replaced ignition wires, distributor cap, and plugs. Before i would have to give the car a few turns to start and give it some gas. Didnt realize that wouldnt be necessary with all the improvments, and soon after experienced my first "carb burp" or something to that efffect and turned my air cleaner into toast, after breaking in the fire extinguisher. After some reasearch on breathers and pcvs on newer cars and a new edelbrock cleaner (with an opening at the bottom) im wondering if my valve cover breather cap should be connected to this? Previous cleaner didnt have this opening. 1. should this breather go to the air cleaner, as i understand the fumes comming out can be/likely are combustible?? and 2, should i be worried about the new ingition wires laying on the valve covers? i thought about wrapping them with heat tape, but am reading conflicting posts about arcing and other things, but i figured these wires (taylor spiro pro) woul be fully insulated? Any thoughts would bre greaty appreciated

Really appologize for the lengthy post but i wanted to get all info in there:

75 bronco sport
crate 302 w c4
670 truck avenger carb
msd electronic ign module.

thanks in advance!!

 

[B RON CO]

Hi, I always use the little plastic wire looms. I am fussy about a lot of the details, and my look tends to be what the guy in the 70s would do. The last thing I want to see is wires going every which way. They won't burn on the valve cover. Look at other Ford engines and see what you like. Welcome and good luck

 

[B RON CO]

Hi, on later cars the breather, which is the intake for the PVC system, uses filtered air through a hose, from the air cleaner to the breather. Older models use a cap with something like steel wool inside. I don't think it matters as long as the Pcv is working. The backfire and fire is very troubling. That could be a lean condition or timing issue or? Did you talk to the mechanic? Good luck

 

[jckkys]

I only had one fire from the carburetor venturis. It was my first Holley rebuild in '66. I left the primary float E clip off. Got a 20 ft. flame with the air cleaner off. Never made that mistake again. A burned air filter implies raw fuel poring down the throttle bores. I would disassemble the Holley and see what's going on. The original EB air cleaners are far better than after market open element types in many ways but the fire safety is much better.
If your crankcase fumes are flammable you have real problems like a faulty mechanical fuel pump that pushes raw gasoline into the crankcase. Nearly all vehicles in the '60s and '70s had a breather from the filtered part of the air cleaner to either the valve cover or back of the intake behind the runners.
It's not a good idea to to have plug wires touching bare metal. It's asking for a short. You can use the original wire looms or one of many billet or chrome plated after market types to show off.

 

[Walrus_in_SA]

Hi, on later cars the breather, which is the intake for the PVC system, uses filtered air through a hose, from the air cleaner to the breather. Older models use a cap with something like steel wool inside. I don't think it matters as long as the Pcv is working. The backfire and fire is very troubling. That could be a lean condition or timing issue or? Did you talk to the mechanic? Good luck

Thanks B RON CO, this makes sense, i do believe i have the cap from older models that you are talking about, so its good to hear that it is a common setup and im not missing something. I did talk briefly to the mech, and he did adjust the timing either "from/to 20 from/or to 25", but thats a little over my head. It started right up from the shop when i picked it up, and drove really well to work, and the same from work to a shopping center at lunch. But when i started it up to head home at lunch, i did hear a quiet pop and the engine wouldnt turn over, and then after running through the checklist in my head, i noticed some smoke billowing out the hood vents, grabbed the extinguisher, lifted the hood and saw some flames comming from the cleaner. Once i got it home via tow truck, got the new cleaner and cleaned out the carb with some carb spray she started right up, no problems at all. not really sure what to think of it, besides an anomoly? Im all ears though . . .

 

[Walrus_in_SA]

I only had one fire from the carburetor venturis. It was my first Holley rebuild in '66. I left the primary float E clip off. Got a 20 ft. flame with the air cleaner off. Never made that mistake again. A burned air filter implies raw fuel poring down the throttle bores. I would disassemble the Holley and see what's going on. The original EB air cleaners are far better than after market open element types in many ways but the fire safety is much better.
If your crankcase fumes are flammable you have real problems like a faulty mechanical fuel pump that pushes raw gasoline into the crankcase. Nearly all vehicles in the '60s and '70s had a breather from the filtered part of the air cleaner to either the valve cover or back of the intake behind the runners.
It's not a good idea to to have plug wires touching bare metal. It's asking for a short. You can use the original wire looms or one of many billet or chrome plated after market types to show off.

Thanks, i havent altered the carb at all myslef, and my mech just checked it and said everything looked good. and i have noticed ZERO problems with it before or after the tune up besides this one event, so im not sure what to make of it. Im not sure that the fumes are flammable, i was just responding to some posts i read . . . and thought maybe i was missing something from the VC caps, but it looks like thats the way it should be setup. There are have been a lot of modifications/upgrades to the engine compartment, so im just having trouble keeping up with what things should look like. Ill be sure to get some looms in there and get them off the covers. Do you think the heat tape could cause the same short? i have some of that lying around and was thinking of wrapping some of the wires where the contact the head, but i suppose that metal tape might cause the same short? sounds logical to me . . .

 

[Broncobowsher]

I've had a small carb fire in the past. Not enough choke and it had a lean sneeze on start up. The low profile triangular foam air filter caught on fire. Come to find out they are very well known for doing that. Also they don't filter for squat, keeps small kids and dogs from falling into the carb. Anything smaller then about a golf ball tends to go right through.

 

[73azbronco]

If you ever get a filter on fire keep cranking and start the motor, guess where the fire goes.

 

[redwards69]

Welcome Walrus! I can't offer a lot of input on the carb issue, but from a wires on the valve cover perspective, I would agree with B RON CO. I like a cleaner look and would simply put some loom around it, or redo it with some longer wire and reroute it around to the firewall and up from the back of the motor.

 

[DirtDonk]

Another welcome Walrus. How about some pics? They'd help us to see if anything is obvious, but we also like to check out the new rides too!

And speaking of backfiring through the carb, can we "assume" that the mechanic checked timing? Or perhaps did they think that because they only changed the cap and rotor, and that it was working before, they didn't need to?
Or another scenario is that the motor has had the balancer, or timing over, or even the entire engine replaced at some point. In these cases, it's far too easy with Fords to get the incorrect ignition timing marks so that you'll never get correct timing without digging a bit deeper. Or just experimenting for best running.
Reason I bring up timing is because burping back through the carb is often a symptom of bad ignition timing.
Not to mention also being a symptom of a vavletrain problem. But we won't go there just yet!

Anyway, pictures can be uploaded to an online hosting site like SuperMotors or one of the MANY out there, or you can post them directly from your computer or phone if you become a contributor for 12 bucks a year. Alternately you can e-mail some pics to one of us with the yellow "contributor" beneath their usernames and we can post them up for you.

Lots of ways to do it. But pics would be cool.

Paul

 

[B RON CO]

Hi, do you have points igntion or electronic? Timing was mentioned, but I had back firing on a different engine caused by a failing condenser. It might back fire from pitted or closed points. Good luck

 

[Walrus_in_SA]

If you ever get a filter on fire keep cranking and start the motor, guess where the fire goes.

Yes!! I think this was the other mistake i made, in hindsight i remember panicking a little when i heard the soft pop and released the ignition. On the phone my mech said to keep on it and things will go right back in the right direction . . . Im sure to stay on it from now on. Learn something new everyday, Thanks!!

 

[Walrus_in_SA]

Welcome Walrus! I can't offer a lot of input on the carb issue, but from a wires on the valve cover perspective, I would agree with B RON CO. I like a cleaner look and would simply put some loom around it, or redo it with some longer wire and reroute it around to the firewall and up from the back of the motor.

Sounds good, ill definately look into them. I was mostly asking because i had some heat tape lying around, but that happens to be metal as well, so i figured id go back to the original setup and see if that was reasonable, not that i like to second guess my mechanic, but it was worth getting lots of opinions. i do enjoy the clean look, but my compartment needs lots of cleaning up . . one thing at a time.Thanks!

 

[gr8scott]

Lots of loom options out there

 

[Walrus_in_SA]

Another welcome Walrus. How about some pics? They'd help us to see if anything is obvious, but we also like to check out the new rides too!

And speaking of backfiring through the carb, can we "assume" that the mechanic checked timing? Or perhaps did they think that because they only changed the cap and rotor, and that it was working before, they didn't need to?
Or another scenario is that the motor has had the balancer, or timing over, or even the entire engine replaced at some point. In these cases, it's far too easy with Fords to get the incorrect ignition timing marks so that you'll never get correct timing without digging a bit deeper. Or just experimenting for best running.
Reason I bring up timing is because burping back through the carb is often a symptom of bad ignition timing.
Not to mention also being a symptom of a vavletrain problem. But we won't go there just yet!

Anyway, pictures can be uploaded to an online hosting site like SuperMotors or one of the MANY out there, or you can post them directly from your computer or phone if you become a contributor for 12 bucks a year. Alternately you can e-mail some pics to one of us with the yellow "contributor" beneath their usernames and we can post them up for you.

Lots of ways to do it. But pics would be cool.

Paul

Ive been meaning to post some pic, will get to that today. When talking to him on the phone, he mentioned that he changed the timing, and the numbers 20 and 25, to or from one to the other. Im not familiar with the specifics of that, but the thing about it is that the engine was running much more stable and smoother after he was done, and since then, besides the obvious event which we speak of. I will add that today, we took the bronco out to go for a hike because a cold front came through and the weather was perfect. Eveything started fine except for a fuel stop where the engine wouldnt turn over until the third long crank. no fire as i didnt pump the gas, just let the motor pick up on its own. stopped for food once more after that, and started right up. So im wondering if carbs have a tendency to need a longer crank when the engine is still warm/hot, other than that, im at a loss. . .The engine is definately not stock, im thinking i came out of a later mustang, and there are lots off aftermarket add ons

heres the supermotors link to some current pics: http://www.supermotors.net/registry/28077

one right after the carb fire, a second better pic of the motor setup, i obviously still have a lot of cleaning to do. there is still tons of extinguisher powder everywhere. and a couple of exterior pics. Thank you again for all of your help. It really is fun getting to know this EB!!

 

[Walrus_in_SA]

heres a better link for some pics:

http://www.supermotors.net/registry/28077/86559