A Carb builders worst nightmare

[Hotcrusader76]

Here is copy of a letter sent to Holley from a customer (not mine :D ) who had a fire after installing his Avenger. Who's fault do you think it is on this one?
My truck caught fire My letter to Holley
06/14/03 11:24 AM Edit Reply
I have a Holley truck avenger that is installed on a suburban with a 388 stroker dart heads 230 solid roller cam.With an edelbrock carb this truck through the turbo 400 and transfer case and the big 14 bolt rear put out 365 hp 350 tq to the wheels.That was with jetting it in my Driveway and making a small timing change on the dyno.Unfortanittly that carb would not run on hills.
Well the truck avenger has been a chore.Mind you I understand a carb needs to be tuned to each individuall engine.And I dont mind doing that.It took me one day to get the mixture screw responsive.Basiccly rich but carb on and off numerous times to check primarys not open to far,and adjust secondaries to compensate.
Secondary needle and seat pluged up from the factory.I had to take it apart and reasemmble it for fuel to flow though it.
Main jetting was not bad but to get the main jetting correct and have a smoothe pull through the power valve was time consumming to say the least.Probablly 10 small jet/powervalve changes to make that work the way I wanted
The secondary spring setup is another pain.They either open to quick But if you slow them down they dont open enough.I planed on fabbing up an adjustable arm betwwen the primary and secondary.(Does Holley offer such a piece)But Figured I should check the secondery jetting First.
So I started on that today.Pulled it apart 3 times.
Well the last time aparentlly one of the CHEAP rubber gaskets for the tube between the primary and secondarie bowls must not of seated proberlly.I gave them a quick look and seemed to be in thier normal position.I guess I did not look close enough.So I fired it up
You guessed it Correct.Fuel pissed out everywhere.. Fire .I am not happy.The Hood was open I shut it right down ran to the garage and was able to put it out on the 3rd bucket of water.
I am glad this is an old truck and not one of my firebirds.
Basic fire damage:Wires ,Cap all the wiring on the firewall , dist, ect.all the vacumm lines,Of course their is melted plastic all over the carb.That needs to come totally apart.It could have been much worse If I was going down the road the truck would be gone,Not to mention my sons quad in the back.How do you explain that to a 10 year old that thier is no money in these tough economic times to replace it.
My [censored] with your product is that with all the fine tuning required with this carb .And the amount of times it needs to come apart to do that you would use quality parts.Mind you this carb cost 389 dollars.All it is is a 4150 with some sort of metering block change and a cross over vent.
The fuel cross over bettween the primary and secondaries is a pain to work with gets stuck the gasket slid over the end of the tube to easily.Basic Junk
I will be changing the float bowls to ones that except a n fittings and running my own line
It sure would be nice if you were to supply those bowls with a fuel line for me.
I would be happy to send you a picture of the mess I have
It seems to me that this carb is very unresponsive to jetting changes.Nothing like my old 4150.
Again it seems to me that this carb is an overpriced 4150 that I can not recomend to anyone unless it proves itself offroad and will run while the truck is standing straight up and down.
I will be posting this letter on Several internet sights I frequent

[ June 14, 2003, 01:44 PM: Message edited by: Hotcrusader76 ]

[Rexone]

My take is that the transfer tube wasn't installed correctly and leaked. Not Holleys fault.
I would also not take my carb to this guy for tuning (but that's just me). Nor have him do any business letters either. :rolleyes:

[Cas]

let alone putting out gasoline fires with water!
with that comment alone, I'd say Holley has no responsiblity at all.
I wonder if he knows about spring loaded needle and seats for off road applications?

[HighRoller]

Those damn Holley carbs!!!I had a similar experience with my boat when I went to change a power valve and either put the old one back in by accident or got it in backwards(possible?).Result?Raw fuel puking into the cylinders and making the engine a hydraulic flame thrower!!!Here's a play by play of my buddy and I.
Okay,crank her over...HOLLLYYYYFU*&INCHRIST STOP!!"
I turned around to see my buddy dancing on the gunnel of my boat avoiding a torchlike flame coming out of the gap between the manifolds and heads!!!!!It would have been funny as hell if it weren't happening on MY boat!!We doused it with the extinguisher and he thought my boat looked very"Christmas-y".I didn't see the humor.....And no,I didn't blame it on my Holley carb,I went and bought a brand new Holley and promptly put over 100 hours on it that season with nary a problem!!

[comin' unscrewed]

Is this guy related to Jeff Foxworthy?

[miller19j]

Lets see I took this thing apart several times and put it back together incorrectly and now its broken resulting in a fire and its your fault.
That makes sense to me :rolleyes:

[malcolm]

I can't say I blame him. The Holleys I've installed lately have run like shit for no reason. Is it to much to ask to have it run at least OK right out of the box? I'd never buy a new one, might as well by old ones if I'm going to have to go through them anyway. Just a little venting, and 2 cents.

[Hotcrusader76]

malcolm:
I can't say I blame him. The Holleys I've installed lately have run like shit for no reason. Is it to much to ask to have it run at least OK right out of the box? I'd never buy a new one, might as well by old ones if I'm going to have to go through them anyway. Just a little venting, and 2 cents. I agree with you on that point, biased or not. I have gone through four Demons that were out of the box brand spanking new and three of them needed some attention before running.
From day to day I get to see all sorts of Holleys, factory and custom builds. It amazes me on how many shoddy builds I come across, incorrect or error in the idle orifices, main and idle air-corrector bleeds being out-of-tolerance for their application, etc. These are all things you would never catch as a novice unless you had records of correct sizing or a trained eye.
Today I took apart a clients carburetor for a Pre-OP6 overhaul which happens to be from a very reputable boat manufacturer's motor only to find one of the emulsion holes blocked off. Why? That is a ass-backwards band-aid modification, and it runs!....fat or course but it runs.
If Holley wanted only one emulsion hole per main than why do the HP Versions have three holes? Hmmm...makes you wonder if that boat companies carb guy really knew what they were doing.
Ya learn something new everyday, functional or not. :D
[ June 16, 2003, 09:16 PM: Message edited by: Hotcrusader76 ]

[HOSS]

Cool! Closed the hood with fire underneath. Then douse with not 1 not 2 but 3 buckets of water. I saw this guy on Jackass. He lit his balls on fire then tried to put them out with WD-40. cry

[spectras only]

Hotcrusader76 , I'll agree there's something wrong going on with holley lately. A young guy dropped by with my friend complaining some idle issues about his brand new holley he just installed on his S-10.First of all the float levels were way too high, The locking screws on the needle valves were stripped :( and to rub salt in the wound ,I pointed out to him that it was a factory holley rebuild that Lordco sold him as new :mad: .Fortunately they exchanged the unit for him,but this shouldn't happen :( .

[Hotcrusader76]

To some extent I don't think it's Holley. It's the people who sell or represent them. But then again I have seen many new Holley's out of the box internally and it makes me question there Qaulity assurance dept.
At any rate...Buyer beware..
~Ty

[Froggystyle]

Hotcrusader76:
At any rate...Buyer beware..
~Ty That is just good advice, whether it is carbs or apples.
The problem with carbs to me, is that they are really the last unknown thing on any boat I build. I feel 100% confident with anything related to fiberglass, interior, fuel delivery to the carb, mechanical, valvetrain, trailer, etc... But I look at that ugly thing on top of the motor and just want to shake sticks at it and sacrifice chickens. I have never understood how it really works, and for some reason don't want to learn. If it works, I am not pleased... I am amazed. When I "tune" a carb and it runs better, I figure I have a new lucky pair of underwear on or something. BTW, "tuning" for me is essentially idle screw and idle mixture. Past that... Completely lost.
When they come from the factory broken... I have a problem. I don't want to become a carb expert. I want to bolt on something that properly regulates fuel according to demand on a given rpm curve. It should be simple... 509 cubic inches, 3000 rpm... you should know how much fuel and air you need.
But it isn't. So, until the day when injection becomes bolt on without a degree from MIT... I am very pleased I know a carb guy!

[cyclone]

3 words..Holley HP Series...i've run about 10 of those carbs on various motors and other than jetting changes, they've needed nothing. All of them worked great right out of the box. I"ve had great luck with the race-series Demon carbs too.

[78Eliminator]

I just think it's funny how this thread is called "A Carb builders worst nightmare", then it goes into the fact that a lot of carbs are not so great out of the box and "Buyer beware".

[Infomaniac]

Froggystyle:
Hotcrusader76:
At any rate...Buyer beware..
~Ty That is just good advice, whether it is carbs or apples.
The problem with carbs to me, is that they are really the last unknown thing on any boat I build. I feel 100% confident with anything related to fiberglass, interior, fuel delivery to the carb, mechanical, valvetrain, trailer, etc... But I look at that ugly thing on top of the motor and just want to shake sticks at it and sacrifice chickens. I have never understood how it really works, and for some reason don't want to learn. Too late pay attention:
Carbs work due to differential air pressures.
The float chamber vent directs atmospheric air pressure to the fuel in the float bowl. This is the high pressure.
The venturis inside the throat of the carb cause the air to accelerate when it flows through. This causes a low pressure. The fuel discharge is located here.
The difference in the high pressure air (atmospheric) in the float chamber and the low pressure air in the venturi cause fuel to start flowing.
The greater the difference in these 2 pressures the more fuel flows. Fuel is metered through the jets on the way out.
More air flow is caused by throttle opening. open the throttle, more air flows through the venturis causing a greater pressure drop which causes more fuel to be drawn out of the float chamber. Or pushed out however you view it.
The level of fuel in the float chamber must be kept just below the discharge level so gravity does not flow fuel for you. The difference in air pressures must lift the fuel through the passages enough to discharge it. The fuel level in the float chamber can be adjusted up or down to affect how and when fuel flows.
Easy enough? Other systems involved - acceleration system - power enrichment system - idle system - air bleeds.
the idle system is pretty cool. Not enough air flow through the venturis to cause fuel flow so the idle system discharges under the throttle blades where there is a very low pressure. Manifold pressure. A lot lower than what is created in the venturi. To keep fuel from running out there all the time the fuel is lifted much higher than the main discharge nozzles before it can get down to the idle discharge.