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Had my carburetor re-built by Mountain Man, re-installed it and now can't keep it running, and when I can keep it running, it runs really rough. Everything I'm reading told me to check all of my vacuum lines, and in doing so, I broke my EGR solenoids (2). It's a 1981 305 from CA.

This is a new toy for me, and is the first time I've worked on a car in 30 years. The vacuum diagram is still on the car and legible except the air cleaner corner is torn off. What I want to do is to disconnect the two vacuum lines going to the carburetor in order to remove/isolate all the EGR/Solenoids vacuum lines. If it idles smoothly, then I've found what vacuum lines need to be fixed. Since I broke both EGR solenoids, the wiring to these will also be disconnected, and the EGR valve will be plugged.

Any harm in testing my new carburetor this way? Can I drive it around town without the EGR solenoids?
IMG_20200714_204350.jpg
 

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welcome Roy

yes you can drive it WITHOUT the EGR connected..

the #1 hose will probly be the Vacuum Supply to open the EGR..
#2 is probly the Vent for the vacuum so the egr will turn off / close..

I not familiar with the '81 2-solenoid setup,
if you could post a pic of those and the
back of the carb where the #2 hose connects..
EMM STICKER SML EDIT.jpg

check all the vacuum lines, see if they are stiff/hard, cracked, leaking..
pinch off each vacuum hose at the carb, see if any make a difference
on the idle..
any chance you mixed them up replacing the carb ??
double-double check the hose route pic..

could be the carb problem you had before the rebuild,
wasn't a carb problem, check everything else before
turning the screws on the carb..
the carb gets test run at MM, so it should work if
everything else is good..
check the EGR Valve too,
if it sticks open, its just like a vacuum leak,, it wont idle..

have you started turning the carb screws yet ??
if not ? don't,, till you do some testing..

use a thinned down pop-sickle stick to prop the throttle open more
at the idle screw, so it will idle, and testing can be done..
 

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Discussion Starter #3
welcome Roy

yes you can drive it WITHOUT the EGR connected..

the #1 hose will probly be the Vacuum Supply to open the EGR..
#2 is probly the Vent for the vacuum so the egr will turn off / close..

I not familiar with the '81 2-solenoid setup,
if you could post a pic of those and the
back of the carb where the #2 hose connects..
View attachment 131053

check all the vacuum lines, see if they are stiff/hard, cracked, leaking..
pinch off each vacuum hose at the carb, see if any make a difference
on the idle..
any chance you mixed them up replacing the carb ??
double-double check the hose route pic..

could be the carb problem you had before the rebuild,
wasn't a carb problem, check everything else before
turning the screws on the carb..
the carb gets test run at MM, so it should work if
everything else is good..
check the EGR Valve too,
if it sticks open, its just like a vacuum leak,, it wont idle..

have you started turning the carb screws yet ??
if not ? don't,, till you do some testing..

use a thinned down pop-sickle stick to prop the throttle open more
at the idle screw, so it will idle, and testing can be done..
Thanks for the response. Here are some more pictures. Looking at the vacuum diagram, the blue hose connecting the solenoid and carburetor is located directly under the fuel filter in the picture. The red hose connecting the solenoid and carburetor can't be connected to the carburetor because the connection is no longer there (but you can see where it would have connected if the port was drilled - there are two bosses on the top plate on the back of the carb). This is where I'm a little frustrated. After all the glowing reviews of Mountain Man, I sent my carb to him to rebuild. He indicated the carb bottom, middle and top were off of 3 different vehicles, and emphasized that it would work properly on my car, so proceeded with the rebuild. When I received the carb back, he had switched the top, so the connection isn't drilled for the solenoid return and now can't be connected to the carb. Enough on that, for now.

After installing the carb and reconnecting all the hoses, I did get it started, but it ran rough and I need to keep the accelerator depressed a little to keep it running. Started doing research and all threads I read lead me to start replacing all the vacuum hoses. That's when I broke the solenoid connections. I suspect they are original and just very brittle for the age - picture attached.

I did confirm that all vacuum hoses are connected properly. The larger hoses appear to be in very good shape and are pliable. The small ones on the EGR and solenoids were in bad shape.

Note that I did not make any adjustments to the carburetor jets nor choke. Everything is set just as MM set them.

So now I'm thinking about just disconnecting the smog pump and related EGR and solenoids, but further research is telling me that I should change the distributor and carb, which is way more than what I want to do to this car right now.

Short term, I'm looking for a work-around just so I can drive the car on weekends. Longer-term, I want to replace the solenoids (if I can find them) and restore it back to original equipment.
 

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I had an issue where I was losing vacuum at the fuel vapor canister causing some pretty rough driving and stalls until I got up to speed. Turned out the plastic inlet tube was cracked and that hose went right to the carb bowl, check for hissing at the canister.
 

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I had an issue where I was losing vacuum at the fuel vapor canister causing some pretty rough driving and stalls until I got up to speed. Turned out the plastic inlet tube was cracked and that hose went right to the carb bowl, check for hissing at the canister.
Thanks! Will do.
 

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wtg Roy, good pics too, thanks
I see the un-drilled port on the top rear..
never seen the 2-egr setup, those 1980.5 - 81's are different..

i'd just connect the 2 hoses together to keep dirt out for now,,
and cap or plug the front vacuum port on the carb..
but maybe leave the egr's connected electrically,,
drive it and see if it set's a code,
then try them dis-connected if you want..

I cant see finding those solenoids new, but if you search ebay a-lot
someone will probly have one for a Vett, so they can charge 3X $$$..

check all the vac hoses, on the cruise, the vacuum ball's,
x2 on the vapor canister,
transmission vac too sometimes it gets bumped..
check those hard plastic vacuum tubes too, to the inside duct's
under the AC/Heat box, and MAP sensor, they get very brittle..
 

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Discussion Starter #7
wtg Roy, good pics too, thanks
I see the un-drilled port on the top rear..
never seen the 2-egr setup, those 1980.5 - 81's are different..

i'd just connect the 2 hoses together to keep dirt out for now,,
and cap or plug the front vacuum port on the carb..
but maybe leave the egr's connected electrically,,
drive it and see if it set's a code,
then try them dis-connected if you want..

I cant see finding those solenoids new, but if you search ebay a-lot
someone will probly have one for a Vett, so they can charge 3X $$$..

check all the vac hoses, on the cruise, the vacuum ball's,
x2 on the vapor canister,
transmission vac too sometimes it gets bumped..
check those hard plastic vacuum tubes too, to the inside duct's
under the AC/Heat box, and MAP sensor, they get very brittle..
Thanks, JJLT1!
 
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