Holley Carb Woes - DCDoug Pay Attention (Long Post)

[elmariachi]

Originally Posted by dcdoug

I too had NOS MR heads that had never even had valves in them. Now I wonder whether he just shared the opinion of Ernie that concern about unleaded gas on unhardened seats is overrated or whether I have hardened seats.

There are varying opinions on this, sorta like Republican vs Democrat. For every person who says you are screwed there is another that says "No worries." Try a borescope and if that doesn't solve your burning desire and you can't sleep, use an additive. But in all honesty I am doing it not as a preventative but as a little insurance. When I finally move up to Blue Thunder or KC heads, if my valve seats are damaged, then I'll have seats installed before I sell the heads. And if the heads are toast (highly unlikely) then I'll add that to the list of sh!t I wasted during my Cobra learning experience. Go ahead with that Holley 3255 and your mind will be off of valve seats in no time. I promise.

[LuvDaBlues]

If I can toss another tid bit of info, if you run a racing fuel, VP or Sunoco, in some cases the dye from the fuel turns into molasses and really goops up the same passages and ports.

The temp and humidity have been pretty high here in Dallas, and I tossed a plastic bag over the carb overnight to keep crap out while running the valves. The fuel evaporated, but the dye stayed behind. The engine ran very sluggish and wouldn't idle. Pulled the carb and spayed and squirted every opening. Blew dry and voilà, ran great.

[Excaliber]

I was professionally wrenching when this change to unleaded and valve seats were a BIG issue. Everyone was panic striken, the sky was falling, were all doomed. Turns out the only folks I ever heard about that had trouble were "traveling salesmen" type. Folks putting a LOT of HARD miles on the engine. Running it long enough that way will eventually damage the valve seat. The face of the valve and the seat tend to weld themselves together. But that takes some pretty extreme heat, temperature AND a lean air/fuel ratio to happen. The way 99% of us drive our Cobras? AND we tend toward the rich rather than the lean side of air/fuel. Aint gonna happen, no way your going to have trouble with the valves/seats.

[Bill Bess]

Put on the biggest fuel filter, one with a cartridge that you can inspect when your change it out. Blow out the carb with air....if no results, take it apart and go through it. Holleys are fun..they are good for about two years of service without some kind of problem.
I'm amazed, going on three years now..still workin fine.
Bill

[Ronbo]

Originally Posted by Ron61

Ed,

I have filters on everything now but the weed eater and it is going to be hard to find one that I can fit into that tiny space and short fuel line. I am looking for some of that gray fuel line that is supposed to stand up better to the ethanol.

Ron

Polyethylene or polypropylene tubing is what you want, should have it at Home Depot or Lowes.

Pat, For fuel lines you can use the teflon lined rubber hose that's commonly used for propane Grills.

[CobraEd]

Originally Posted by Ron61

Ed,

I have filters on everything now but the weed eater and it is going to be hard to find one that I can fit into that tiny space and short fuel line. I am looking for some of that gray fuel line that is supposed to stand up better to the ethanol.

Ron

Ron,

I long ago stopped using my weed eater. I "edge" all the borders in my front and back yard with GRASS & Weed killer spray. Do it once in the spring and all of your borders are edged for the year.


.

[tmareina]

I've got 2 Holly 4224's (660's) on mine and have had no problems in over 9,000 miles...haven't even had to adjust them. Maybe I've been lucky...thanks for the info...I'll keep it in the back of my head incase I encounter a problem later.

Tom

[dcdoug]

I'm not sure if something similar happened to me or not on Sat. Car was running great, stopped at a friends house for 20 min. Then had issues on the way home with sputtering at times and stalling twice while idling (started back up with a little, but not too much effort). But other times the car ran great. I did have the issue a week ago with almost running out of gas and needing to use the lower pick-up on the electric pumps to get to the gas station. Since I really never run the electric pumps, I was thinking that is sucked up some crap from the tank.

But when I checked the filter, it was pretty darn clean. I did blow out the air bleeds with carb cleaner and it ran OK today, but I didn't have much of a chance to drive it. I guess I'll see next time.

By the way, I did change out the coil a few weeks back (because it was red and had to go, now its the spare I carry) - would a bad coil cause something that felt more like a fuel issue? I can obviously switch them and see if the problem persists, but thought I'd ask in the meantime.

[patrickt]

If it re-appears, immediatly put the old coil back in. There's always the wild card issue of oil-filled coils being mounted sideways, so you get an increased mark on a response if you include it. I bet you just clogged up the bleeds a little bit with that goofy two-step you did with your fuel pumps last week. A blast of carb cleaner down all of the bleeds will probably make it go away.

[dcdoug]

Originally Posted by patrickt

There's always the wild card issue of oil-filled coils being mounted sideways, so you get an increased mark on a response if you include it. I bet you just clogged up the bleeds a little bit with that goofy two-step you did with your fuel pumps last week. A blast of carb cleaner down all of the bleeds will probably make it go away.

The coil is mounted vertically. Bleeds blasted with carb cleaner.

Hopefully, I'm good. I'll report back if I'm not.....

[patrickt]

You should also try and keep your car's tank as full as possible when it's just sitting. This morning it was 92% humidity and very chilly. Condensation forms on the inside of your tank pretty easily.

[RodKnock]

But there's more gas to spoil and coagulate, especially today's fuel.

[patrickt]

Originally Posted by RodKnock

But there's more gas to spoil and coagulate, especially today's fuel.

As little as you drive you probably ought to run StaBil just as a matter of course. Supposedly our gas around here starts to go bad in as little as 60 days.

[RodKnock]

Originally Posted by patrickt

As little as you drive you probably ought to run StaBil just as a matter of course. Supposedly our gas around here starts to go bad in as little as 60 days.

Hmmm, it was sunny and about 78 degrees today.

Did I get my car out of the garage?

[patrickt]

http://www.fuel-testers.com/expirati...hanol_gas.html

[dcdoug]

Originally Posted by RodKnock

Hmmm, it was sunny and about 78 degrees today.

Did I get my car out of the garage?

Come on RodKnock, WTF? Drive that thing!

[dcdoug]

Originally Posted by patrickt

You should also try and keep your car's tank as full as possible when it's just sitting. This morning it was 92% humidity and very chilly. Condensation forms on the inside of your tank pretty easily.

I generally do. I also drive it weekly, hardly ever more than two weeks.

[Argess]

Accolades to Patrick for this thread, and also to me for remembering it 13 years later. Identical symptoms to Patrick I followed his advice and lo and behold, it now idles perfectly. So thank-you Patrick... and be careful getting your head through a doorway!

[patrickt]

If everyone reading this would just go out and clean their air bleeds the world would be a better place.

[CompFi]

Originally Posted by Argess

Accolades to Patrick for this thread, and also to me for remembering it 13 years later.

Definitely appreciate Argess for bumping this thread back to the top of the stack. And for Patrick for his original post.

My engine is now having issues. Suddenly running rough, fouled plugs etc.

Even though I always run "ethanol free" fuel, I am zeroing in on my Holley carb as the likely culprit. As this thread makes clear, time to go clean out the air bleeds.