Acceleration rough L-82 350 help

[Charles P.]

Re: Acceleration rough L-82 350 help

I just replaced the fuel filter-It looked good but the construction was slightly different then the old stock AC GF427 that I put on it tonight. The one I removed was made in Israel and had a rubber sleeve inside it with a metal spring. The old stock ac one I put on it was open on one side with a paper gasket applied to one end.
Joe, Martin-- I have a full tank of gas in it now so it may be hard to visualize the bottom of the tank. I stilll have to road test it now with the new filter on it. I would love to think that was it but as I said the old one except for being made in Israel and being constructed differently didn't look too off.

What effect does water have on the sock? I ask because if after I use this fuel up and I see any water in the tank, I suppose that would be my next step. What does it take to get to? Does the spare tire carrier assembly including the upper have top come off. If I access the tank will I need a new gasket also? Part numbers available in the AIM I presume or would the gas tank come as an assembly?
Thanks for the replies--I had my family over for supper and I was raving about how great the folks on this board are.

[Joe C.]

Re: Acceleration rough L-82 350 help

Okay, if I squint I can see 1973 1974, which probably comes from the profile we filled out. But what if the question is about another model year or the profile is wrong or not updated for a new acquistion?

The point I am trying to make is that the model year/engine option should be clearly stated with an engine related question or the type of transmission if it's a transmission related question, etc.

We know the L-82 is a 350, but the configuration details changed over the L-82 run depending on the year iincluding the ignition system.

It makes it a lot easier on me, and most others if basic information like the model year/engine option is specifically stated with an engine related question or any other salient information that is necessary to identify the specific system or component based on model year and option configuration.

Duke

Duke,

The "1973/1974" icon that you refer to can be enabled only if you post including a "quote" from the original post, or in "advanced" mode. If you "quick reply" most of the functionality is not available! This has nothing to do with a poster's profile, but enables the poster to indicate which model year(s) he/she is talking about.

I always look in poster's profile to find "missing" information. And I make correct assumption about 95% of the time. More often than not, when a poster is talking about a car that's not his, he/she will state " sorry for the stupid question, but a friend of mine is having a problem with his car..............". You see, if one assumes, it doesn't always make an ASS out of U and ME.

What Joe is referring to is the "signature". It is a "sign off" that is automatically added to anyone's post if one enables that option. Go to "edit profile" to do so.

Are you back on the "sauce"? Your spelling and punctuation have not been up to par, lately.

Joe

[Joe L.]

Re: Acceleration rough L-82 350 help

I just replaced the fuel filter-It looked good but the construction was slightly different then the old stock AC GF427 that I put on it tonight. The one I removed was made in Israel and had a rubber sleeve inside it with a metal spring. The old stock ac one I put on it was open on one side with a paper gasket applied to one end.
Joe, Martin-- I have a full tank of gas in it now so it may be hard to visualize the bottom of the tank. I stilll have to road test it now with the new filter on it. I would love to think that was it but as I said the old one except for being made in Israel and being constructed differently didn't look too off.

What effect does water have on the sock? I ask because if after I use this fuel up and I see any water in the tank, I suppose that would be my next step. What does it take to get to? Does the spare tire carrier assembly including the upper have top come off. If I access the tank will I need a new gasket also? Part numbers available in the AIM I presume or would the gas tank come as an assembly?
Thanks for the replies--I had my family over for supper and I was raving about how great the folks on this board are.

Charles-----


I agree. For the type of problems you're having, I think that you'd be able to see something "abnormal" with the filter. Still, it would be wise to test drive it before you go further in the process.

You should be able to test for water in the fuel by draining some fuel out at the carburetor (disconnect fuel line and crank the engine without starting to pump some out). Place it in a clear glass bottle and observe for phase separation.

I think I'd look in some other areas before I tried to check out the in-tank fuel strainer. As Duke suggested, ignition might be the next thing to look at. I think I'd install a new set of points and condensor and check the ground wire on the breaker plate at the same time.

[Martin N.]

Re: Acceleration rough L-82 350 help

I agree with Jim. Let the car settle down for awhile and look at the fuel in the fuel tank with a flashlight. Maybe that's a good place to start. It'll save some $$$$ hopefully in the long run. You just don't want to start throwing parts at it.

Marty

[Harmon C.]

Re: Acceleration rough L-82 350 help

I had about the same problem with a rebuilt carburator. The filter got pluged and I found junk in the bowls and under the jets.

[Clem Z.]

Re: Acceleration rough L-82 350 help

the inside the carb fuel filters with a check valve were used on the cars that had the fuel pump return line to the tank to prevent the float bowl from empting when the engine was shut off. also the paper filter with the metal ends, about .700" dia should not fit into the filter nut on carbs used with a sintered bronze filter, about.650" dia as the metal end has a larger diameter than the sintered bronze one.

[Charles P.]

Re: Acceleration rough L-82 350 help

I road tested the car for about an hour with the new AC GF427 filter and no problems at all. I even went on the road course here that is mostly set up for the IRL St Petersburg Grand Prix next week and did some accelerations with good power and also several interstate on ramp accelerations and higher speed accels without a problem.

I checked the fuel tank when I got back with a flashlight but it looked pretty benign. I will check again when the fuel is lower. I suppose this means it could have been the filter. It also could be a gremlin like a loose wire as Duke stated. It just seemed fuel related because of the way it acted while throttling it up.

Below is a pic of the fuel filter that came out of it. The blue thing in the middle is a rubber plug which has a spring behind it. This is not on the ac part which is open and has a paper gasket around the open end side.
If I didn't know better I would say it was some sort of flow restricter like on a shower head.
This was the first time I replaced it on this car which I have had for about a year. The carb was redone shortly before I got it.

[Charles P.]

Re: Acceleration rough L-82 350 help

Clem, I don't have a return line. Was the wrong filter in there?

[Duke W.]

Re: Acceleration rough L-82 350 help

Duke-----


In this case, you don't need to strain your eyes to see the left margin icon. The cars Charles owns are contained in the signature section at the bottom of his original (and subsequent) posts. It includes model year, engine RPO and transmission. Same style and font size seen in the rest of the post.

What if he's talking about a car other than those shown in the signature? Well, I suppose then he'd better state exactly what he's talking about.

Signature? I don't see no stinking signature! I haven't had a brewsky since UCLA beat East Mississippi Valley State LAST WEEK! Maybe I should drink MORE!

Go Bruins!

Duke

[Joe L.]

Re: Acceleration rough L-82 350 help

Signature? I don't see no stinking signature! I haven't had a brewsky since UCLA beat East Mississippi Valley State LAST WEEK! Maybe I should drink MORE!

Go Bruins!

Duke

Duke-----


You don't see a listing of the cars at the bottom of Charles' posts? If not, you're looking at a completely different screen than I am.

[Clem Z.]

Re: Acceleration rough L-82 350 help

Clem, I don't have a return line. Was the wrong filter in there?

yes that was the wrong filter if you do not have a return line from the fuel pump to the tank. i has also seen people put the filter in backwards even though the filter is larger diameter in the closed end to prevent this.

[Joe L.]

Re: Acceleration rough L-82 350 help

Clem, I don't have a return line. Was the wrong filter in there?

Charles-----


You should have a fuel return line. In fact, there should be TWO---one on the right (passenger) side which goes from the fuel return nipple on the base of your fuel pump all the way adjoining the fuel supply line to the fuel tank where it connects near the top of the right side. There should be another one on the left side which goes from the vapor cannister to the top left side of the fuel tank. The one that clem is talking about is the one on the right side, though.

[Joe L.]

Re: Acceleration rough L-82 350 help

the inside the carb fuel filters with a check valve were used on the cars that had the fuel pump return line to the tank to prevent the float bowl from empting when the engine was shut off. also the paper filter with the metal ends, about .700" dia should not fit into the filter nut on carbs used with a sintered bronze filter, about.650" dia as the metal end has a larger diameter than the sintered bronze one.

clem-----


Although some Rochester carbs may have been originally fitted with the sintered bronze filters (my 1969 was), I don't think that GM has ever serviced that style filter for those applications. The GM SERVICE filter has been the paper style, AC GF427 aka GM #5691393. This filter is the SERVICE filter for all 1968-74 Corvette applications with Q-Jet. I think there are some aftermarket sintered bronze style filters for 68-74 with Rochester, though.

As you described, for Holley carbs the filter was definitely the sintered bronze style. It's currently known as AC GF455 and it's still available.

1975-80 Corvettes used a longer paper-style inlet filter. For 1975, it was AC GF441, aka GM #5650906. For 1976-77 it was AC GF471, aka GM #5651803.

All 1968-80 Corvettes with Rochester carbs used a right side fuel return line. For 68-69, the line originated at the GF-432 fuel filter. For 1970-80, it originated at the nipple on the base of the fuel pump.

Actually, there was ONE Holley-equipped Corvette application that used a fuel return line. What was it? 1971 with LS-6.

[Clem Z.]

Re: Acceleration rough L-82 350 help

some of the early Q jets use filter # 7013404 the bronze one( holley type) because i have rebuilt some that the paper filter( GF-427) was too large to fit into the filter nut.

[John H.]

Re: Acceleration rough L-82 350 help

Duke-----


You don't see a listing of the cars at the bottom of Charles' posts? If not, you're looking at a completely different screen than I am.

Joe -

Duke probably has "signatures" turned off in his options, as I do (force of habit from "other" boards, where "signatures" frequently describe everything that has ever been done to the car, including the brand of glue used to attach the carbon-fiber ashtray cover) .