biackbenz

This is the hose between the vapor canister (carb bowl) up to the upper left side of the carburetor on my 1978 L82. I am pretty certain that this splice is not supposed to be there. The hose sections are different.

But somewhere I think I read that there may be a restrictor in one of these lines. The splice piece is just an open piece of tubing so I can't see this as any type of restriction. The AIM does not show this splice.

I am replacing the hoses and thought I could confirm that this splice does or does not belong. Sure would appreciate it if someone could confirm.

Thanks

SwampeastMike

No, it does not belong. I just replaced all of the hoses in my '79 L82 (identical in that regard) as well.

The splice is likely there because the upper part of the hose turns to chewing gum. If anything like mine the short hose that connects from the fuel line to the canister will be in hideous condition.

I don't envy you the job. Expect filth even if you think your car is clean. You have to remove the cruise transducer and disconnect the washer reservoir. There are five lines at the canister. Four are in two "booted" pairs of the type on the manifold vacuum switches. I don't think the boots are available and the kit I got from Doc Rebuild did not include them. Most of the Doc Rebuild hoses did not fit into the boots (a PAIN to remove but in surprisingly good condition) but all but one fit to the connection. The single, center connection leading to the fuel line needs the original boot.

Do yourself a favor and replace the cruise and washer hoses while you are there!!!!

If you haven't done it before also replace the "emission" hoses available in a great kit from Doc Rebuild. I truly could not believe the difference in performance and comfort (think FAR quieter while cruising) after replacing all of my hoses! The wife who gave it to me two years ago saying, "Make it work as well as it looks" was finally pleased.

After this latest work there were only two original vacuum lines left in the car. One from the brake pedal switch to the cruise control. The other the little piece connecting the metal transmission modulator line to the modulator valve at the transmission. After a 300-mile Sunday cruise in what seemed like a "new" car guess what happened the next day?
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No shifting from the transmission! That little hose at the transmission had failed!!!!

biackbenz

Thanks Mike,

I am in the process of replacing all the rubber hoses. I removed the canister from underneath the car. I removed the rocker cover and a small triangular panel behind the wheel well. At that point relatively easy to get at it. I am going to replace the windshield washer hose as well. Because the washer does not work, I may be replacing the pump too. I'm glad you said that about better performance because I am expecting that as well. Amazing how some of the simple, and cheap, fixes can do so much for performance.

Don't have to worry about the transmission or cruise control hoses. I have a 4 speed and no cruise.

SwampeastMike

The washer pump appears to be integral to the tank as it is attached with plastic "rivets". I moved the tank nearly every way possible and it would not come out. I won't say that it's impossible but the brake booster seems to be in the way.

The performance difference was remarkable. More power delivered more quickly. Much better cold starting. FAR quieter when cruising on the highway.

SwampeastMike

That's what I forgot to remove this time!!!! I was down in that are doing some work once before and has the canister loose relatively easily. DOH! No real matter though as I was replacing all of the hoses anyway.

Giant_Robot

I have THE EXACT same splice in my line to the canister (77) ..
was wondering the same, and why it was there...

dembo

Original Quadrajet or a replacement carb? Most Holleys and Edelbrocks don't have all the ports. Is it the hose where the PCV T's in to?
Nick

arklacat

Is a 77/78 much different than an 81? I just replaced my lines. The double boots were shot. I just used fuel rated hose on the one going to the carb and the one going to the tank hardline. The others I just used regular vacuum hose and reused the Y that connects the two right off the canister. I don't recall the carb hose having any kind of a boot but I have the old hose at the house and will check. The hose that went from the canister to the air breather wasn't replaced. The new canisters don't have a nipple for a hose. I assume the canister used to draw air from the breather and now just gets it from the air around the canister.

I haven't driven the car since replacements. The first few days afterward the gas smell was much much less than before but then about the 4th or 5th day it got bad again. But then this morning almost now smell at all.

biackbenz

I have the original Q-jet. The hose with the splice went from the caister to the "Y" fitting connecting to the PCV valve and carb. Further inspection looks liike the canister side of the splice is vacuum hose and gas hose on the other side. I think somone had removed the carb at some time and maybe cutting that line was easiest or maybe the upper part of the hose was bad and only replaced half of it because getting to the canister was too much trouble.
I finished replacing the carbon and have most of it back together.

I tried to replace the washer pump but gave up. Too many other things I need to do and I think its going to get warm again and I want it on the road.

arklacat

My carb hose did indeed have a boot. but for the life of me I cant see why it needs the original boot. I cant see any kind of mechanism inside the boot (or any of the other boots.) Why do you say it is needed?

arklacat

I took my canister out intending to replace the charcoal and filter myself (I'm not sure the 81 has a replaceable filter, I couldn't see where the canister would open to get to one and I didn't see it in the shop manual) but after pricing a new, made in usa one at the local parts store I went with the new one cause i'm lazy like that (and apt to screw up the replacement anyway.)

And I guess gm wised up on the 81. I replaced my washer pump while I was at it. My pump inserts thru the bottom on the resevoir and is held in place with a screened nut from inside the tank and wasn't too awfully had to accomplish even though I couldn't get the tank out of the wheel well area. (I did have it unbolted so that i could move it around. and it was even a bit easier because the canister was removed.) However, I guess gm didn't get it all right because that's the second time I've replaced that pump. both times the pump neck that inserts through the hole in the resevoir has broken off at the screened nut.

Zorro O

On my 79 I wanted to see what condition the hoses on my canister were in so I just unbolted the plate that is under it behind the fender. After that the canister fell out of the car onto the garage floor. The bracket was lose (fastener is in the wheel well) and the hoses had rotted away. You might find going after this stuff is easier from under the car. My back likes laying on a creeper a lot more than bending over the fender.

biackbenz

Well, I decided to go for it and fix the washer pump. Still cold in Wisconsin. Hardest part was convincing myself that I would bee able to replace the screw holding the washer bottle to the mount located next to thefthefender - you can't see it. Really wasn't hard. All back together. New carbon, new hoses and a working winshield washer.

SwampeastMike

Make sure the vapor hose coming from the carb has a nice downhill run to the canister with no dips. Not sure if it comes from condensing vapor or from fuel in the bowl but small amounts of liquid fuel go down that line and will accumulate in the dips if it doesn't have that constant downhill slope.