vacumme line diagram for 1970 350 with 4 barrel
#1
vacumme line diagram for 1970 350 with 4 barrel
Alot of my vacumme lines where not hooked up when i got the car anyone have a diagram or now where i can find one. thank you in advance. Also what would cause the motor to bog a little when starting out but run fine all the other time?
#2
A bit more information might be helpful.
- Eric
#3
Im going to start with the vacumme lines first and then retune the idle. I think it is probably the accelerator pump dried out as the car was sitting for 3 years. i think what better describes it is a slight hesitation. Also when it is in drive and idling it is rough and shakes the car.
#4
#5
Ok Here is a list of the vacumme lines as my engine doesnt seem to match up.
-PCV VALVE lined to front of carb.
-line from transmission going to manifold
-line from distributor going to front of carb on the right
-metal heat tube 1/4 " or smaller is going to the back of the carb and connected with a small piece of tube. Where this connects to the carb it has a metal elbow coming off the carb and this is hooked to the manifold.
-The last connection is a tube going from the manifold to a plastic cylinder on the firewall and then a hose going from that to the heater valve of some sort on the manifold.
Does this sound right.
Also what is the pillar on the front left side of the block in the manifold that has 3 barbs coming out of it?
The only hose that looks to be wrong is the pcv valve as it is very easy to slip on and off the carb and where the pcv valve connects there is a hose clamp.
-PCV VALVE lined to front of carb.
-line from transmission going to manifold
-line from distributor going to front of carb on the right
-metal heat tube 1/4 " or smaller is going to the back of the carb and connected with a small piece of tube. Where this connects to the carb it has a metal elbow coming off the carb and this is hooked to the manifold.
-The last connection is a tube going from the manifold to a plastic cylinder on the firewall and then a hose going from that to the heater valve of some sort on the manifold.
Does this sound right.
Also what is the pillar on the front left side of the block in the manifold that has 3 barbs coming out of it?
The only hose that looks to be wrong is the pcv valve as it is very easy to slip on and off the carb and where the pcv valve connects there is a hose clamp.
#6
It sounds like everything is connected right.
There was no mention of a power brake booster, but you may have manual brakes.
I would recommend disconnecting and capping all of these connections (or one at a time), to see whether your idle improves.
If that doesn't do it, then go around all vacuum connections and lines, and all carb and intake mating surfaces with the flammable substance of your choice - starting ether, propane, carb cleaner - to see if the idle picks up when you spray it into a particular spot, so you can be sure you don't have a vacuum leak.
The thing with the three barbs is a Thermostatic Vacuum Switch, which is designed to provide full manifold vacuum to the vacuum advance when the engine is too hot, but ported vacuum (that barb on the right front of the carb) the rest of the time.
If you are using ported vacuum for your advance, as you are now, the TVS may help to keep your engine cooler in traffic on a hot day, but if you switch to full vacuum for your advance, then you don't need it.
- Eric
There was no mention of a power brake booster, but you may have manual brakes.
I would recommend disconnecting and capping all of these connections (or one at a time), to see whether your idle improves.
If that doesn't do it, then go around all vacuum connections and lines, and all carb and intake mating surfaces with the flammable substance of your choice - starting ether, propane, carb cleaner - to see if the idle picks up when you spray it into a particular spot, so you can be sure you don't have a vacuum leak.
The thing with the three barbs is a Thermostatic Vacuum Switch, which is designed to provide full manifold vacuum to the vacuum advance when the engine is too hot, but ported vacuum (that barb on the right front of the carb) the rest of the time.
If you are using ported vacuum for your advance, as you are now, the TVS may help to keep your engine cooler in traffic on a hot day, but if you switch to full vacuum for your advance, then you don't need it.
- Eric
#7
Eric,
Found a leak at the carb to manifold connection after spraying it with starter fluid. Once this was found I checked the tightness and it was not at the 14 ft-lbs I found in the manual for the carb to manifold bolts. Torqued them down and it runs a lot better but not where I want it.
Before I was lucky to get 18 in of vacume in park now im at 21 in of vacume.
next question, for the tvs if this is not hooked up to anything and the barbs are not plugged does this cause a vacume leak? or does it have to be hooked to the manifold in another location?
Found a leak at the carb to manifold connection after spraying it with starter fluid. Once this was found I checked the tightness and it was not at the 14 ft-lbs I found in the manual for the carb to manifold bolts. Torqued them down and it runs a lot better but not where I want it.
Before I was lucky to get 18 in of vacume in park now im at 21 in of vacume.
next question, for the tvs if this is not hooked up to anything and the barbs are not plugged does this cause a vacume leak? or does it have to be hooked to the manifold in another location?
#8
Found a leak at the carb to manifold connection after spraying it with starter fluid. Once this was found I checked the tightness and it was not at the 14 ft-lbs I found in the manual for the carb to manifold bolts. Torqued them down and it runs a lot better but not where I want it.
Before I was lucky to get 18 in of vacume in park now im at 21 in of vacume.
Before I was lucky to get 18 in of vacume in park now im at 21 in of vacume.
It's not doing anything just sitting there, and can be safely ignored.
If you're really motivated, you can put a wrench on it, remove it, and replace it with a bass pipe thread plug (use Teflon tape), but if you do, don't throw it out, because you or someone else may want it some day.
- Eric
#9
Eric,
im not that motivated at this point. Just trying to get all the cars done and ready to make a 300 mile trip.
I never throw away anything for these cars, I still have the original manifold and 2 barrel carb that was on my 1970 delta 88.
Again Thank you for all the help.
im not that motivated at this point. Just trying to get all the cars done and ready to make a 300 mile trip.
I never throw away anything for these cars, I still have the original manifold and 2 barrel carb that was on my 1970 delta 88.
Again Thank you for all the help.
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