View Full Version : Nova L78 with Holley 4557 - vacuum lines
Diamond_Don
04-03-2016, 04:13 PM
Many, many years ago the original Holley carburetor was stolen off my 1970 Nova. It was replaced with the listed GM counter exchange part way back then. Now I have purchased the correct 4557 carb to re-install. Interesting enough I found this carb locally, within 15 miles from where the original carb was stolen. Wow - grumbling - did I just buy back my own carb!
At any rate, this carb is a little different from the one I had on. I have tried to look for good pictures of how the hose lines for this carb should be plumbed, but most pictures have air cleaners on and are hiding what I actually want to see. The valve covers do have two (hose?) clips on the top edge. This car had no smog equipment when I bought it and I am not planning to put any smog stuff back on it.
Any pictures would be much appreciated. Thanks
http://www.yenko.net/ubbthreads/pics/usergals/2016/04/full-19693-41716-carb_pic.jpg
WILMASBOYL78
04-03-2016, 04:44 PM
This should help...the metal tube shown in the photo actually has a curl in it as you move towards the front of the motor...hoses connect to the TCS vacuum switch and the smog pump. I probably have a few more photos showing the rest...but, you said you weren't interested in the smog stuff.
http://www.yenko.net/ubbthreads/pics/usergals/2016/04/full-1121-41734-fuel_line_bracket.jpg
Diamond_Don
04-03-2016, 05:14 PM
Yes, this is the kind of view I am looking for. But, I have none of those smog thing-a-ma-jiggy parts. I might be able to route the hose from the distributor using the valve cover clips and then up some how so that there is no interference with the air cleaner base. I just don't want this to look too much like a fast "bush fix". If it blends in and looks close to original - that's what I'm after. I got the car when it was 3 years old, but, there was no fuel line reinforcement as shown in this pic. Did they all come with that fuel line reinforcement?
Thanks
SS427
04-03-2016, 05:48 PM
DC engine. <<GRAEMLIN_URL>>/smile.gif
Henry D
04-03-2016, 09:57 PM
DC Engine??
WILMASBOYL78
04-03-2016, 10:20 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Henry D</div><div class="ubbcode-body">DC Engine?? </div></div>
Dennis Cumby...the grumpy old geezer with the black LS6..it's kind of nice car <<GRAEMLIN_URL>>/rolleyes.gif
WILMASBOYL78
04-03-2016, 10:24 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Diamond_Don</div><div class="ubbcode-body">Yes, this is the kind of view I am looking for. But, I have none of those smog thing-a-ma-jiggy parts. I might be able to route the hose from the distributor using the valve cover clips and then up some how so that there is no interference with the air cleaner base. I just don't want this to look too much like a fast "bush fix". If it blends in and looks close to original - that's what I'm after. I got the car when it was 3 years old, but, there was no fuel line reinforcement as shown in this pic. Did they all come with that fuel line reinforcement?
Thanks </div></div>
Yes...all the L78/LS6 vehicles came with fuel line support. I assume you have the correct 70 fuel lines and junction block..?? You can run the vacuum hose using the tube and support clip and then tee into the choke vacuum pull off hose. The other 'thing-a-ma-jiggy' parts could always be added down the road.
**the clip holding the distributor vacuum tube is attached to an intake manifold bolt...not the valve cover.
wilma
Early assembled cars,used an entire rubber hose for your red arrowed port,and that manifold Tee too.And no added valve cover finger clips either..
They went to those pictured hard metal lines & clips soon afterwards.
Diamond_Don
04-03-2016, 11:59 PM
Hi, thanks. I have the reproduction fuel lines and block I obtained from Inline Tube. It seems I am missing more pieces than I had originally thought. I have no other obvious clips or brackets on my intake manifold as shown in my case - picture attached.
Should anyone find a another good picture representation of the 4557 carb from the pass side with no air cleaner, it would be great if they could post it for me. I'll leave it to the car's next custodian to take on the task of adding the proper smog stuff.
http://www.yenko.net/ubbthreads/pics/usergals/2016/04/full-19693-41751-20160403_163355.jpg
Salvatore
04-04-2016, 01:34 AM
maybe buy a Nova assembly manual with pictures. Pretty clear pictures that Tom Williams sent you. I believe everything is available in repop if need be.
Diamond_Don
04-04-2016, 06:33 AM
Didn't have to buy an assembly manual, it turns out the schematic is shown right here in the Technical & Restoration post titled "Nova TCS Switch & Wiring Gutter 101".
Anyway, I have been reading more about this magical TCS system. I can see my car once had this, the TCS temperature sensor is still in the exhaust manifold and the switch attached to the gutter is there as well.
I now have this vague recollection of my first carb in my mind. I seem to recall that there was nothing attached to the carbs TCS port! The attached picture shows a close up view of the hose system from the distributor to the TCS solenoid to the carb.
http://www.yenko.net/ubbthreads/pics/usergals/2016/04/full-19693-41762-tcs_hoses.jpg
The purpose of the TCS was "prevent the vacuum advance unit from becoming vacuum locked at an advanced position" and "temperature override system which provides full vacuum in all gears when the engine is cold for improved drivability". While I obviously didn't have a working TCS system, I certainly don't remember any cold engine or other drivability problems. Go figure.
Thanks for your thoughts everyone.
WILMASBOYL78
04-04-2016, 11:45 AM
Don...the temp sender is in the pass. side cylinder head. There are several wires that are part of the TCS system. There is one group of wires that connects the rain gutter relay to the sender in the head...the other wires are wrapped in black and come out of the harness near the wiper motor and run along the pass side valve cover to the TCS vacuum switch by the carb. There is also a switch in the tranny that completes the whole deal...if you look you will probably find the wires stuffed in somewhere or possibly cut off.
*The thread on the site that touches on some of the aspects of this:
http://www.yenko.net/ubbthreads/ubbthreads.php/topics/372492/1
That's my TCS solenoid close up pic I took on my Chevelle a few years ago.
Glad you found it,as I was getting ready to post it for you.
Zman1969
04-04-2016, 02:11 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WILMASBOYL78</div><div class="ubbcode-body">This should help...the metal tube shown in the photo actually has a curl in it as you move towards the front of the motor...hoses connect to the TCS vacuum switch and the smog pump. I probably have a few more photos showing the rest...but, you said you weren't interested in the smog stuff.
http://www.yenko.net/ubbthreads/pics/usergals/2016/04/full-1121-41734-fuel_line_bracket.jpg
</div></div>
Tom, do you have any photos like this for a 1969?
Diamond_Don
04-04-2016, 03:04 PM
Based upon WILMASBOYL78 information I went back and started to look more carefully at the wiring along the firewall... and, found another wire with a bracket tucked away!
If this is the other TCS wire described then you have convinced me to put things back together closer to the stock configuration.
I'm learning lots (as a sixty year old) newbie! Thanks
http://www.yenko.net/ubbthreads/pics/usergals/2016/04/full-19693-41770-20160404_074651.jpg
Salvatore
04-04-2016, 03:15 PM
Put a set of headers on that bad boy and re-curve the distributor then you will not have to worry about all that other junk.
WILMASBOYL78
04-04-2016, 03:17 PM
That is the wire that goes to the transmission....keep searching you will find the others.
Nice detective work...
wilma
YENKO DEUCE REGISTRY
04-04-2016, 03:17 PM
That wire actually goes to a solenoid switch located in the side cover of the transmission, the clip attaches to a bellhousing bolt. That is how the TCS system knows that the car is in 4th gear.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By:
[email protected]</div><div class="ubbcode-body">Put a set of headers on that bad boy and re-curve the distributor then you will not have to worry about all that other junk. </div></div>
I wish to buy all your "junk" Samula.
Don
Look for a green passenger side TCS terminal wire plug too,like this.
Diamond_Don
04-04-2016, 11:26 PM
Yes, it's there. The car is a 04A build date, so it sounds like it's just on the cusp of the production change from the all rubber hoses over to the metal connector pieces. It's great that members are able to share pictures like those in this thread, because now I'll be able to use them to source the parts and complete the set-up!
Thanks to all the sYc members who keep passing the old knowledge down the line.
(I promise I'll never call the TCS system parts the "thing a ma jiggys" again!) <<GRAEMLIN_URL>>/smile.gif
WILMASBOYL78
04-04-2016, 11:49 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Diamond_Don</div><div class="ubbcode-body">Yes, it's there. The car is a 04A build date, so it sounds like it's just on the cusp of the production change from the all rubber hoses over to the metal connector pieces. It's great that members are able to share pictures like those in this thread, because now I'll be able to use them to source the parts and complete the set-up!
Thanks to all the sYc members who keep passing the old knowledge down the line.
(I promise I'll never call the TCS system parts the "thing a ma jiggys" again!) <<GRAEMLIN_URL>>/smile.gif </div></div>
Don...04A would not be considered 'on the cusp'...these cars first showed up in September of 1969...there were a number of changes in the Dec-Jan time frame. An early car would be late August to late October..maybe early November.
You are right about the SYC members...incredible wealth of knowledge here and folks like to help. Please let us know where to mail the bill <<GRAEMLIN_URL>>/naughty.gif
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