Currently restoring a 75 cutlass. I was replacing rubber hoses and noticed some had little pins in them. What are these used for and do they need to go back in?

 

Are you talking about little stubs of nylon in one edge of each radiator hose?

Those are left over from the little nylon loops used to hang the hoses on the hooks in the store.

Welcome to ClassicOlds.

- Eric

 

No these small pins I found on the small hoses under the air filter housing. Guessing these are vacuum hoses

 

In the olden days in areas where smog laws were against modifying the pollution controls and had visual inspections, people used plugs inside the hoses to disable these controls. This may be what your looking at.

 

show a pic of these "pins"

Are you perhaps not in the USA?

 

Here are 2 pins i found

 

Perhaps photos from additional perspectives would help, too.

And maybe a little less rug...


- Eric

 

Can you post the tops of the pins?

 

1side is open other side closed

 

Live in az,usa

 

Are they solid on one end? Picture is blurry.

 

Yes solid 1 end open on other

 

Where do the vacuum lines run that had these in them?

 

Never seen anything like 'em.


- Eric

 

I will have to take a pic of where I found one at when I get home from work later on tonight. It was a group of hoses that were right in front of carb

 

Those plugs are used for the E4ME and E4MC carburetors to cap the mixture control solenoid adjustments. The plugs prevent tampering and seal the float bowl so the vapors do not escape. The plugs are not indigenous to your ’75 as they first appeared in 1980/81. Someone was probably just using them to plug the vacuum lines.

 

I thought that they were pellet gun ammo, and I like the 'rug', looks homey.

 

So should I put them back in or will it be fine without them?

 

You need to figure which lines were plugged. Like I said above they were probably used to defeat something.

 

x2

 

This is where i found those pins in these hoses...now to try to remember which hose had it. Any idea which hoses would have these pins?

 

Follow the hose that had the plugs and tell us or take picture of the item they stop at.

 

Better pic in daylight. Im exactly sure which hose they went in but i think they went into those 3 way hose connectors. One goes toward the front of carb and the other goes to...im guessing a sensor.....

 

 

That is the source of the vacuum lines, where do they go from there?

 

One hose goes to this which is on the side of distributor

 

The other one goes to this aluminum pipe that goes behind the engine....not sure where it goes to

 

I don't know why those 2 would be blocked off. One is your vacuum advance and the other should be your transmission vacuum modulator. Both are necessary.

 

Yeah I was shocked to see it blocked/restricted. Would it be bad if I just leave them out? Will this affect emmisions if I go to get tested?

 

You need to see if the vacuum advance is working now, because if it was blocked it was not before. Second I don't believe on of them came from the metal line that runs to the transmission as it would have caused problems shifting.

 

I need to put on a new fuel pump, filter then I can start it up. If the vacuum advance is working or not working what will I notice or signs to look for?

 

I don't think you got the message of some earlier posters:

Those objects look like the idle screw caps used on much later electrically-modulated carburetors.

They are anti-tamper screw caps, used to prevent the end user from adjusting his idle mixture screws - they are routinely removed from the screws and discarded so that the screws can be adjusted.

They are garbage that someone stuffed into your vacuum lines, for reasons unknown.
They do not belong there.

Next you need to read the Emissions section of the Engine chapter of your Chassis Service Manual so that you can understand the operation of all these parts, and then test them to see whether they work.

- Eric

 

Start the engine.

Pull the vacuum advance hose off of whatever it's attached to and plug that hole.

Suck on the end of the hose. The engine should speed up.

Hold the pressure in the hose with the end of your tongue or your fingertip - it should not leak out.

If the vacuum advance unit doesn't work, it needs to be replaced.

If there is a leak, you need to make sure it's the diaphragm and not the hose, and then replace the offending part.

- Eric

 

I will try this weekend. Some background....I took to emissions just to see how it would do...failed cause of high hydrocarbons on idle. Decided to change spark plugs (good thing cause gap was wrong), spark plug wires, distributor cap, fuel filter, filter for purge canister that had a hose disconnected, pcv filter, another filter opposite side of pcv ( forgot name). It was hard to start when it was cold but after I changed this stuff it was easier to start. Other than that though it ran smooth

 

High HC at idle may be a misfire, maybe rich mixture. Try adjusting idle mixture to best vacuum then in [lean] until you get a 50 RPM drop per screw. Or, in [lean] until misfire then back out a tad.

You can if necessary take vacuum line off distributor vacuum can, plug the hose, pass your emissions test, then re-attach the vacuum advance. California used to make me do this dance. The problem is, w/o the VA, the engine would overheat when stuck in traffic, and was low on power.



"Any idea which hoses would have these pins?"
=========================
None.
NONE of the hoses should have these plugs. Installed by a clueless person.

The fingers in the photo REALLY help for scale.

 

Did they get rid of TCS by then? That's about the only thing I'd ever plug.