nitsud08

I have a 67 mustang with a 6cyl 200 and a few nights ago while driving on the freeway, my car started to act like it was out of gas. i pulled over to find out that a freeze plug that is located right under my carb had fell out. after getting it towed home, i messed around with it, and poured a small amount of gas directly into the carb to find it coming straight out of the exposed hole. I have talked to a few people and have received different opinions. some say that it is a good chance the freeze plug fell into the engine, and others say it is pretty unlikely that it fell in. I remember the freeze plug being very difficult to put in in the first place, so i am hoping it didn't fall inside.

Am I going to have to take my engine apart to ensure it didn't fall inside? or is it unlikely? and does anyone have any advice on how to actually look for it? haha i still need to take the carb off tomorrow and look down inside, but not sure if those freeze plugs are magnetic or not

thanks a lot for any advice

67t5ponycoupe

Freeze plugs go to the water jacket and it is very unlikely that it went into the engine. When you put gas down the carb you should not get any fuel out of the missing freeze plug so I am confused. Is the missing plug in the block or the intake manifold? Can you post pictures?

nitsud08

The plug is on the intake manifold, right below the carburator. Before i noticed it was missing, i took the fuel line off to test my fuel pump, and i got a good amount of squirts. then i pour some fuel into the carb and it came out of the open whole that i am point to in the photograph. after i poured in some fuel, i would try and start the car and it would start but only stay on for 1 second and rev up really high and just turn off. i would imagine this is due to a vacuum leak. but i posted a picture of where exactly i believe the problem is. thanks again for any help guys!

rtintwo

Most likey it fell out and is laying on the side of the road. You have already run it some so any damage is already done if the plug went inside the motor.

If you want to make sure its not inside the motor and before ripping the motor apart i would recommend calling some rental places and see if you can get a fiber optic boroscope. I can rent one locally for 25 dollars a day. Feed it through the casting hole look at all the intake valves and if you dont see the plug and all the valves look good, then you will know it had to have fallen outside. 25 dollars is cheaper than what you would spend on gaskets, fluids and misc stuff. Also the less a good motor is taken apart the less chance of fixing it till it is broke.

kalli

i never heard or saw a freeze plug falling in. it's always out

2+2GT

Not supposed to be a freeze plug there, that's a later model head with provision for an EGR.

urban_cowboy

I concur. A freeze plug is just that. It is a plug designed to pop out in the event that the water coolant freezes to allow for expansion instead of cracking your block. That is something else and is probably why it fell out. As for where it went, that is the manifold plenum. It is under vacuum due to the pistons sucking in air & fuel. The plug could have sucked in or it could have vibrated out. I would check it out.

JMD

A freeze plug is really misnamed, after casting the holes they fill are used to clean sand from the casting, I have never seen a freeze plug save a frozen engine, every time I have seen or heard of one being popped out it always meant the block was toast.

Back on track, I largely concur with the opinion that if the plug was going to do damage, it would have PROBABLY already done so, it looks pretty big, big enough to get into a valve but too big to get past the valve.

At this point I would take the advice for the fiber optic bore scope (maybe because I have one), if it checked out I would take my chances. I don't think I would take it apart.

To fix the hole, to me the easiest most sure way might be to make a plate, drill and tap a couple holes, (1/4" or smaller) a little gasket sealer and DONE.

Smokeybear31

I popped two last winter. One on each side of the block above the motor mounts. Put em back in and everything was/is fine. They DO work as freeze plugs.

nitsud08

I assumed it was called a freeze plug. I can see that a freeze plug would only pop out due to frozen engines, but if this plug came loose due to air pressure or just random bumps on the road, it might be possible that it fell inside. Does anyone know if the metal is magnetic? or would having to get a snake with a camera on it be the best route?