last question on needles and seats

[spstan]

So I got two correct needles and seats from Mike's Carburetor (not an advertisement but he did treat me square). Car started and ran great for about 2 months. Then the other day started dumping fuel and wouldn't start. Suspected dirt on needles and seats so I cleaned them. Car started and ran great today (so far).

What to do; 3 options as I see it A) buy new needles and seats and replace them every 2 months (don't like this idea) B) put two gas filters in line to insure clean gas. My race car neighbor doesn't like this idea; he says it would cause too much resistance to fuel flow or C) replace or clean fuel tank. New fuel tank (if I could find one would probably be over $500) and I don't know what cleaning and examination would cost. What would you do? Paul

 

[Big_John]

I think the question to ask is "why dirt is getting by the gas filter?"

So that begs the question of "what gas filter are you using and where is it located?" Are the hoses/lines in good shape?

While I really don't like the clear plastic filters, it might be good to install one to monitor the gas. Just don't buy a glass cased filter! (glass breaks and fire ensues). If you are using a metal can filter, maybe cutting it apart and looking at the element is a prudent idea.

As far as two filters inline, I don't think that's not going to significantly reduce flow. Really, there is a sock type filter on the end of the gas pickup to filter out the big chunks, so there already is 2 filters inline if you think about it.

If the tank is that bad, maybe it is time to take more drastic action. Even at $500, how much aggravation might it save, and how much $$$ are you spending now screwing around with this.

 

[CBODY67]

On the "damaged" needle and seats . . . how are they being damaged? It is the seating area or the end of the needle? Are they pure brass needles or have a viton tip? Can the seats be re-touched with a small drill bit to restore them and/or can the viton tips be wiped clean of any debris?

Personally, I would not be opposed to using a Fram opaque fuel filter in the line going to the fuel pump. In theory, it might hamper flow a bit, but in a normal drive-around car, where fuel needs are not that great, how might that make a big lot of difference? In this case, they could be a significant diagnostic tool.

IF you're going to consider replacing the fuel tank, also put "new fuel lines" in that mix, too. Stainless steel lines rather than normal steel lines (like you now have). "Rust" can happen in them, too.

If "debris" is damaging the needles and seats, are there any accumulations in the bottom of the float bowl of such things? How is it NOT getting into the main jets or accelerator pump feed? Is the debris hard granules or otherwise?

Additionally, on the top of the venturi cluster are some holes. These are also calibration points for the main and idle systems. The smaller ones are for the idle circuit and should be above the brass idle tubes. When those holes are closed (on topside) or decreased in effective size by deposits or such, that makes that circuit head to "full rich", to the point that with the engine running, fuel will dribble from the venturi. The venturi cluster should be removeable, so next time, you can sight down those holes to look for obstructions/accumulations.

One other consideration. At a seminar on carburetors given by a Holley engineer I attended back in the 1980s, the issue of "trash in the fuel line" was mentioned. He observed that when an engine is stopped and sits for a while, normal evaporation of fuel in the float bowl can occur. Which can result in a bit lower fuel level. When the engine restarts, the initial fuel flow will be a bit un-regulated, so it's at "full flow" until the float rises and the needle/seat is then used to regulate the flow after that initial "full flow" situation. The longer the engine sits, the lower the float, and the more unregulated flow results.

Until you can identify the source of the debris which is allegedly in the fuel, plus determine how it got past the normal fuel filter, then any dollars spent can be in vain.

Just some thoughts and curiosities,
CBODY67

 

[spstan]

C; the needles are brass with a viton tip. Fellow on you tube says not to use drill bit to clean seats; instead he uses a q tip attached to electric drill and some lapping compound ( I used Brasso). Didn't check the Venturis (just happy to have the car running as smooth as it does now). I think I'll replace the fuel filter and see how it does. It's not a matter of dollars but of emotional well being. I hate chasing the same problem twice. Paul

 

[Just Carbs]

Boat tanks in the bilge are notorious for rust. And they are often cover by a full interior that sits on a non-removable fiberglass cockpit floor. BIG bucks to service the tank. As in north of $3k, plus the tank.
So, we use "big" spin on canister filters and new lines between the filter and carb.

 

[413]

Yes how are the lines and rubber hoses, if they are shedding crud and are after the filters it won’t matter. Your fuel system is causing you grief, not going to stop without further action.

2 filters won’t hurt a stock type engine driving down the road. I do it on these occasions.

Valve lapping compound on carb parts? Not a goood idea.

 

[spstan]

Yes how are the lines and rubber hoses, if they are shedding crud and are after the filters it won’t matter. Your fuel system is causing you grief, not going to stop without further action.

2 filters won’t hurt a stock type engine driving down the road. I do it on these occasions.

Valve lapping compound on carb parts? Not a goood idea.

Yes how are the lines and rubber hoses, if they are shedding crud and are after the filters it won’t matter. Your fuel system is causing you grief, not going to stop without further action.

2 filters won’t hurt a stock type engine driving down the road. I do it on these occasions.

Valve lapping compound on carb parts? Not a goood idea.

"valve lapping compound on carb parts? Not a good idea" - you have a reason for stating this? Paul

 

[Just Carbs]

They lap smooth but not centric. Been there done that. 50/50 success.

 

[413]

You are altering the shape of the needle, and introducing grit from the compound, which needs to be removed before use.

"valve lapping compound on carb parts? Not a good idea" - you have a reason for stating this? Paul

What were you removing from a 2 month old needle and seat that you felt you needed the abrasives of valve grinding compound?

Was it a piece of rust scale or rubber hose stuck in the seat? Or was it goo and varnish From old gas? Both can be cleaned out with spray cleaner and the Qtip by hand. you(we) need to know what was in there to know how to fix the problem.

Biggest problem with this fix is people read this at home and think it‘s a good idea (it’s not) and then everyone is doing it and think it is the way to go. Like using spray on bedliner on a classic car.

 

[Boydsdodge]

What carb is it?

 

[CBODY67]

Possibly "YouTube Influencer" strikes again? A drill bit is not OK, but liquid abrasive/polish is? Either one can make the seat non-concentric, seems to me. Anything other than a carburetor cleaner should not be needed, to me. If you need to re-surface the seat in the housing, that must be some serious debris coming through them, especially to need to use an abrasive to make the seat usable again. Something about this whole deal seems a bit out of whack.

Certainly, a yayhoo with a drill bit can be a dangerous pairing, in general, but I suspect that is not the case here. Some sort of drill was used to make the seat in the first place, so care should be used with any drill bit there. Possibly NOT putting it in a drill motor, but using it as a twist drill instead. Even turning it the wrong direction rather than in the cutting direction. Still, just how badly has the seat been eroded in the first place? How has the viton tip been compromised? Is the debris magnetic?

Y'all have fun!
CBODY67

 

[spstan]

What carb is it?

Boys; its a Holley 4175 spread bore. Anyway after cleaning the needles and seats the car started and ran fine 3 times in a row. Then, leaving the library it wouldn't start. Toe truck driver got it started with a jump. Only this time IT IS DIFFERENT.

Tow truck driver and I could not smell any gas so I'm pretty sure the carb is not dumping fuel anymore. I'm turning my attention to the timing chain cause I've read a bad (loose) timing chain can cause hard starting issues. Thoughts? Paul

 

[413]

A timing chain will not caus an intermittent problem.

??does the carb have fuel in it? Does the accelerator pump spray fuel when you move the throttle? Take out a lower float bowl screw and see if it has gas in it.
does,it have spark? something else could go bad at anytime.

spray a short blast of starting fluid down the carb, does it start?

Is there a good repair shop nearby that can helip you?

 

[spstan]

A timing chain will not caus an intermittent problem.

??does the carb have fuel in it? Does the accelerator pump spray fuel when you move the throttle? Take out a lower float bowl screw and see if it has gas in it.
does,it have spark? something else could go bad at anytime.

spray a short blast of starting fluid down the carb, does it start?

Is there a good repair shop nearby that can helip you?

413; what are the symptoms of a loose timing chain? would it make the car hard to start? Paul

 

[spstan]

413; what are the symptoms of a loose timing chain? would it make the car hard to start? Paul

413; could a bad ballast resistor cause an intermittent starting problem or is a ballast resistor an all or nothing proposition? Paul

 

[CBODY67]

IF a timing chain jumps one tooth, the car will become hard to start. Cranking like it just gets to the edge of starting, then doesn't. Some spit-backs through the carb can happen too. Sometimes, you can advance the distributor one notch (as in one spark plug wire terminal) and it can run better, but not all the way better, by observation.

A timing chain either works or it doesn't. No intermittent or other symptoms that it's getting ready "to go". No hard starting, no loss of power as such, no off-idle hesitations, etc.

The 4175 Holley spreadbore vac secondary is a good carb design. I've had one (emissions-spec replacement for a '79 Corvette L82) on my '77 Camaro for well past 200K miles with none of the issues you have mentioned. So I know they can be good carburetors. What spec is the one you have? How did you decide on that carb?

This car has electronic ignition, correct? If it does, the control box has to have a minimum battery voltage to fire the plugs. From my investigations, an Orange Box takes more than normal voltage in the battery to work. If the tow truck driver jumped the battery and it started, THAT might be one issue. Plus those boxes need to have a great ground connection to work, too. Might get a normal replacement control box and install it, making sure the screw and box body have a clean metal surface against which to ground to.

One night, many years ago, we were at a cruise-in. Everybody was getting ready to leave. The Challenger R/T parked next to my friend's HemiCuda would not start. It cranked over very fast so it was not a battery issue, or didn't appear to be. Another guy there got his jumper cables, attached them, and suddenly the car started. It ran fine after that. It had a Chrysler Orange Box on it.

It should be easy to check the ballast resistor by removing it and looking at the backside of it. Using a meter to check continuity and resistance.

I know how frustrating some of these things can be, plus how expensive tow charges have gotten to be in present times. If you don't have "alternative transportation", now might be the time to consider such? So these repair issues can come later in a less-stressful time, hopefully.

Take care,
CBODY67

 

[spstan]

IF a timing chain jumps one tooth, the car will become hard to start. Cranking like it just gets to the edge of starting, then doesn't. Some spit-backs through the carb can happen too. Sometimes, you can advance the distributor one notch (as in one spark plug wire terminal) and it can run better, but not all the way better, by observation.

A timing chain either works or it doesn't. No intermittent or other symptoms that it's getting ready "to go". No hard starting, no loss of power as such, no off-idle hesitations, etc.

The 4175 Holley spreadbore vac secondary is a good carb design. I've had one (emissions-spec replacement for a '79 Corvette L82) on my '77 Camaro for well past 200K miles with none of the issues you have mentioned. So I know they can be good carburetors. What spec is the one you have? How did you decide on that carb?

This car has electronic ignition, correct? If it does, the control box has to have a minimum battery voltage to fire the plugs. From my investigations, an Orange Box takes more than normal voltage in the battery to work. If the tow truck driver jumped the battery and it started, THAT might be one issue. Plus those boxes need to have a great ground connection to work, too. Might get a normal replacement control box and install it, making sure the screw and box body have a clean metal surface against which to ground to.

One night, many years ago, we were at a cruise-in. Everybody was getting ready to leave. The Challenger R/T parked next to my friend's HemiCuda would not start. It cranked over very fast so it was not a battery issue, or didn't appear to be. Another guy there got his jumper cables, attached them, and suddenly the car started. It ran fine after that. It had a Chrysler Orange Box on it.

It should be easy to check the ballast resistor by removing it and looking at the backside of it. Using a meter to check continuity and resistance.

I know how frustrating some of these things can be, plus how expensive tow charges have gotten to be in present times. If you don't have "alternative transportation", now might be the time to consider such? So these repair issues can come later in a less-stressful time, hopefully.

Take care,
CBODY67

CB; I replaced the original distributor with an MSD distributor and the mechanic was able to eliminate the electronic control module. However the ballast resistor is still functional. Maybe I'll try replacing the ballast resistor. For now I'm going to park the car over the winter and replace the timing chain. I don't expect any miracle cure but at around 80K miles the chain probably needs replacing anyway. As the Bible says perseverence builds character. Thanks for the info. Paul

 

[413]

you the same guy with white smoke out the carb a few months ago? And timing chain worries since April?

yes I agree with your post about you needing an electric car. Sell this dinosaur and get a battery car with a warranty.

 

[spstan]

413: changed the ballast resistor and the car started this morning (old resister I kept in glovebox looks thicker than the one I got from Advanced Auto). Keeping my fingers crossed that it keeps starting.

As for an electric car, I have my eye on a Chinese company called NIO. They're promoting battery swap tech. Like a gas station only it takes about 10 minutes to swap the battery and you don't own the battery. I envision battery swap stations replacing filling stations across the US. Paul

 

[CBODY67]

Key thing on anything EV is the supporting infrastructure AND how soon it gets built-out. In looking as some websites a while back, they had small battery packs which were the size of a roll-around carry-on flight suitcase. Take it with you when you go. One way to diminish range anxiety.

In the end, different battery tech will win the day, plus standardized plug-in connectors. I read of an evolutionary-tech battery using more common materials that, when put in a Tesla, went 752 miles before needing a recharge. Another issue is to ensure that all future battery upgrades are backward compatible so older vehicles can be upgraded as time progresses. Hard to upgrade when the battery pack is the vehicles floor pan!

In the mean time, until the EV supporting infrastructure is expanded, a hybrid can be the best deal. One whose EV distance is close to one's daily driving routine. We had a sales manager with a Cadillac CT6 hybrid. He lived a bit inside of the EV range, so he drove to work, plugged it in, drove home, plugged it in. He said he had not bought any gas in over a year. Worked for him. And that technology is NOW.

Enjoy!
CBODY67