1968 Finally getting my HCS on the road again! - Startup procedure

[admin]

Hi Daniel,

So when you say "smog" I think thermactor pump and CA smog system, which our HCS cars shouldn't have. (at least mine doesn't) Do you mean the "IMCO" system?

I dug up the following diagram and according to it my vacuum hoses from the distributor are reversed from what they should be. The funny thing is that it ran fine for years this way.

Here's my current setup:


And here's the diagram:

 

[Ruppstang]

Hi Daniel,

So when you say "smog" I think thermactor pump and CA smog system, which our HCS cars shouldn't have. (at least mine doesn't) Do you mean the "IMCO" system?

I dug up the following diagram and according to it my vacuum hoses from the distributor are reversed from what they should be. The funny thing is that it ran fine for years this way.

Here's my current setup:
View attachment 18942

And here's the diagram:

+1 mine does too.
Marty

 

[admin]

+1 mine does too.
Marty

Marty,

Yours does too what? Have the vacuum lines reversed as compared to the diagram?

 

[CougarCJ]

I don't use the thermal vacuum switch. Ported vacuum to the S nipple on your vacuum advance. I would test that OEM vacuum advance for function. Most of them have bad diaphragms.
Tim O'Connor can rebuild them.
http://428cobrajetcars.com/services

 

[robert campbell]

The S connection is the key. Anytime vacuum is present at this connection it will retard the timing of the engine. Anytime these engines run in a "more retarded" condition you lose gas mileage, power, increase heat, and may experience a rougher idle.

If your initial timing set with the timing light is a bit more advanced you may not experience some of the above symptoms, but you are experiencing the above to a lesser degree.

The P port is from a "ported" source on the carb and does not have any vacuum at hot idle if the carb is adjusted properly. As soon as you crack the throttle plates, vacuum should become present and advance the engine timing. And if the diaphragm at the P port has failed you will experience very poor running characteristics. Especially if the S port is still operational.

Ensure both diaphragms will hold air and move the advance plate in the distro by sucking on the rubber hose and watching the plate with the cap off.

If I had a car with this system I would plug the line going to the S port so it never retards the motor. You can do that and still leave the hose on and no one is the wiser. Then fine adjust the timing to the best it can be. But that is me. The auto industry found out that by running a car more retarded it put out less emissions. But in my opinion the trades offs with this early attempt were not worth it.

Rob

 

[68wsr]

+1 mine does too.
Marty

Hi Jon,

I mean "IMCO" when I said smog. On my HCS the prior party did try to compensate the vacuum retarding by advancing the static engine timing. But the engine was still running rough. I plugged the retard side of the vacuum advance and set the static engine timing to factory spec (6 deg BTC). And my engine runs fine now. I can't explain why your car runs ok with your vacuum lines routed as shown.

Daniel

 

[Ruppstang]

Jon I actually misread your post. Mine is exactly as the diagram and it operates perfectly. But every thing has been restored. If authenticity is not important to you Rob is correct the are way to make it run more efficiently. In 1968 Ford was working to cut emissions. With todays technology's and Rob it can have reasonable emissions and performance too.
Marty

 

[robert campbell]

Jon,
I would submit that the diaphragm for the "S" port is punctured or your static or initial timing is a bit advanced. If the hose for the "S" port was on the "P" connection it would still run "ok". Any vacuum signal to the P side will advance the engine.

It would be interesting to test the vacuum on the "S" hose or side of a properly operating system. As I remember the Distributor Vacuum Control Valve is in the thermostat housing or very near the thermostat? My gut tells me that when the engine is cold there is little vacuum present to the S connection allowing the engine more advance to operate the engine during the choke phase of the engine warming up. As the engine warms up it will allow more inches of vacuum to the S connection that will retard the engine and "reduce" emissions so to speak. That was the wisdom then. When an engine is enriched during the choke phase it produces a lot of emissions anyway and sometimes that is when the engine requires the very best in timing and spark.

Or I am all wet and the opposite is happening which is less vacuum as it warms up! I think the valve does open gradually based on heat rather than just an on or off situation. A bet my friend Marty could run this test!!! They have radiator caps with thermometers in them from Mr. Gasket. One could easily watch a vacuum gauge and the cap at the same time. Of note, if I am correct, at full operating temp you get the full on vacuum from the manifold source to the "S" connection. This means a full 17 to 18 inches of vacuum at the S connection. And at hot idle the P connection is provided "ported vacuum" from it carburetor source. At hot idle the P connection on a properly adjusted carb will have zero vacuum. In 1968 cars idling produced the most emissions I guess they figured. So with zero on the P side you had max retarding of an engine at idle. Again why they idled so rough and also heated up in traffic. As soon as you open the throttle the P side gets vacuum to combat the S side and pull the advance plate forward giving the engine more advance. A bet the engineering that went into the two diaphragms size and travel was extensive to allow the forward one (P) to pull against the back one (S)....

And you wonder why all this crap got unhooked!!! It can remain for concourse cars, but it can be disabled a bit.

To bore you more, the government motors approach in the late 60's was an electrical solenoid on the passenger valve cover bolt near the distributor. It was an on and off switch controlled by a sensor on the tranny. In 1st and 2nd there was no fluid pressure against the tranny solenoid and the engine got zero vacuum advance. When it shifted into 3rd the tranny solenoid was pressurized and sent 12 volts to the valve cover sensor and opening full advance to meet the demands of 3rd gear operation.

The funny thing was passing another car. You pushed the pedal to the floor in 3rd gear to go around a car, and when it downshifted to 2nd the engine lost about 10 to 12 degrees of advance and fell flat on its face so to speak unless you had the carb buried! Once you got some speed up it shifted to 3rd and blamo, started running better! These cars ran like crap under light carb loads in 1st and 2nd gear around down on flat ground.

I bypassed/unhooked a bunch of those back in the day! A ten second fix that really made a difference in how a car ran.

Rob

 

[admin]

Well the last time I worked on the Mustang it was one step forward, two steps back.

I got the valve covers off and all looked good. No major build-up of gunk. Then I went to change the oil, which proceeded to take another 3 hours.

The oil filter would not budge. First I tried a strap wrench, which broke after I put some muscle behind it. It also punctured the side of the filter. So I punched a large screw driver all the way through the filter, which has never let me down as a last resort. Well, it did this time. The metal of the filter housing simply ripped apart and I'm left with just the collar where the filter threads into the block.

At that point I can't get any leverage on it, so I proceed to remove the oil sending unit, fuel pump and PS pump. Not really part of the plan for that day.

I then take a break (ie. cool down for my temper) and run to the parts store to pick up a better oil filter wrench (the pliers style). But still I can't get it to budge. Finally I take a torch to it thinking I can melt the rubber washer a bit. Not the safest plan perhaps, but I had 2 fire extinguishers handy just in case. That actually worked and I was finally able to break it loose.

 

[68sunlitgold]

Jon,
Wow...the rubber seal must have turned into glue! Another simple task that one estimates will take all of 15 minutes turns into 3 hours! I have been there.

Doug

 

[admin]

Made more progress on the HCS this weekend, but still didn't get her started.

I did turn the engine over and it cranked very smoothly. It took some time, but oil finally got up to the rockers, so I buttoned the valve covers back up.

The reason I couldn't actually start it is fuel. I'm not getting any from the tank. I unhooked the fuel line right before the pump and cranked the engine while keeping my thumb over the hose. It's getting suction, so the problem is further back. So I blew on the line to the tank and was able to put enough pressure in there to pop open the pop-open gas cap! :smile: So that tells me no blockage in the line back to the tank.

It's possible that I don't have enough gas in the tank. I only have about 2.5 gals in there, but it's enough to show up on the dash gauge. I would have thought that was enough to suck into the pickup.

I'll add more gas this week. If that doesn't solve it I guess I have to drain it again and pull out the sending unit to inspect the filter and pickup again. :undecided

 

[rvrtrash]

When mine sits for a while, it takes forever to get gas up to the carb again because the engine doesn't turn over as fast cranking as it does at idle and the system isn't primed. Take the air cleaner off and put about 2 tablespoons of gas in the top of the primaries, then turn it over. It should start right up, and start pulling gas from the tank. It might take a second application of gas at the carb, but that should solve your problem.

Steve

Something else I just thought of. If your rubber hoses are old, they might be collapsing on the inside due to the ethanol in the fuel. They'll expand when you apply air pressure, but collapse again with suction. If the engine doesn't stay running with the above mentioned fix, look at the rubber lines. There's one right at the tank and another under the driver's side A pillar that joins two metal sections together.

 

[Ruppstang]

Steve is right, I am pretty sure if you prime it will start up. I usually start with 4 gallons to also check the gage. It should read 1/4. We have also jacked up the back to get the tank higher than the front to help get the gas to the pump.
Marty

 

[robert campbell]

Rob's GNS gas line as it goes forward after the rubber line that Steve mentions that is under the drivers seat. NOT GOOD!! You cannot see this area as it goes through the torque box area. As soon as I tried to remove the rubber hose, I had PLENTY of gas..... on the floor.....

 

[Midnight Special]

When mine sits for a while, it takes forever to get gas up to the carb again because the engine doesn't turn over as fast cranking as it does at idle and the system isn't primed. Take the air cleaner off and put about 2 tablespoons of gas in the top of the primaries, then turn it over. It should start right up, and start pulling gas from the tank. It might take a second application of gas at the carb, but that should solve your problem.

Steve

...And when gas gets to the carb. Watch closely in the first few minutes if running to make sure it doesn't resemble a garden sprinkler (I believe this is what happened to Donna). Dried gaskets & hose connections will often spew for a short time at first. Shut it down for about a half hour and re-start and it likely won't leak... Ultimately replace all old lines & gaskets.

 

[admin]

I was finally able to get the old HCS running today!!!!!!! :grin::grin:

Thanks for the suggestions on my fuel problem. I put another gallon of gas in the tank (about 3.5 gal total) and then manually siphoned gas down the line by hooking up a hand pump at the engine bay. It's just as well because the gas that came out at first was pretty nasty. After I started getting clean fuel I reconnected the fuel system.

Once the carb was getting fuel it started right up! Yeah!!! :smile: But after a minute or so gas started to leak out of the vent at the top of the bowl, then actually shot out of the two tall vent stacks! (yes, I had my fire extinguisher at the ready)

So I popped the top off the carb and checked the float needle for debris. It looked OK, so I reassembled and started it up again. Again, it started to leak gas from the bowl vent after a couple of minutes, although not out the stacks this time. I repeated this process a couple of times hoping that maybe debris in the gas was keeping the needle open and flooding the bowl.

Next I removed the needle seat to be sure I hadn't forgotten to put the gasket at the base. When I looked inside the seat there was something almost completely blocking it. I pulled it out, but I'm still not sure exactly what it is. Either very hard brittle plastic or a rock. How it got in there I have no idea. Once I pulled that obstruction out gas stopped leaking from the bowl. It doesn't really make sense to me, but I'll take the fix.



After running for several minutes I noticed that the fuel pump was leaking at the seam. This may have also been why it took so long to suck fuel from the tank. So back to the parts store for a new one.

A short video of the engine right after initial start up.

 

[joedls]

Good work!

 

[Ruppstang]

Cool Jon, bet it was thrilling to hear it run again after all that time.
Marty

 

[admin]

Thanks Joe and Marty. Yes, it's good to hear it running again. But I'm still running out of time to get it road worthy by the end of this week in time for Fab Fords.

A couple of items still on my list:

Brakes - The master cylinder is bone dry with flaking gunk at the bottom. I'll need to clean or replace and completely flush, then bleed the brakes. New wheel cylinders will be in order as well.

Exhaust Smoke - Even after warm up there's still some gray smoke from the exhaust. It might have a tinge of blue in it, but I've never been a great judge of smoke color for diagnosing engine problems. :embarass: It's fairly thin smoke, but definitely noticeable and hangs in the air. It's not billowy white, so not a coolant leak. Based on the smoke color I'm guessing either oil blow-by from worn piston rings or leaking valve seals.

 

[Ruppstang]

I would add a QT of Lucas oil treatment and drive it. It may come out of it. I had a 81 Mustang that made a blue cloud when we first started it after two QTs of the Lucas no smoke. A rebuild is still the best cure.