I have a 72 f100 custom 302 engine, pulled the number one value stem seals this past weekend and the intake seal had metal rings around it with a number 1345 IPC on top, the exhaust seal had no metal rings just rubber numbers 165 3010 on top. So does this sound correct and what is the best seal for this engine ? One guy said that all his seals are the same with no rings, thinks they are better than the ring ones . Any thoughts appreciated.

 

Originally the engine would have had regular umbrella seals. It sounds like the heads have been redone and the guide boss machined for positive type seals. Those numbers may or may not be useful. You need to measure the diameter of the guide boss and find a seal that will fit. If you only need the two seals your best bet is to go to an automotive machine shop and see if they have a couple.
There are a bunch of different types of positive seals. If your heads do not have bronze guides, I would not use positive type seals. Cast iron guides need more lubrication than a positive type of seal will allow.
Valve Stem Seals - Cylinder Head Parts (ussealparts.com)
VALVE SEALS 11/32" - Alex's Parts Sales (alexsparts.com)

 

Yep, like Crop Duster said, your heads have been serviced at some point. They would have had the plain umbrella seals on intake and exhaust from the factory. The positive seals with the spring are aftermarket products. I have seen shops use those seals to band-aid loose guides on the intake to reduce spark plug fouling.

 

The guy I brought the truck from ,said it sat for a long time before he brought the truck. He has 72 also that he replaced the value seals with the umbrella type, said the new seals stopped it from smoking. So he told me to get the umbrella seals . I did not have value guides , so should I get the umbrella type and try it and see if it stop the smoking ? Thanks for two websites.

 

I just posted those links to give you an idea of how many different seals there are. You can get the stock umbrella seals at your favorite parts store. But unless the seals that are on your heads have deteriorated to the point, that they have fallen apart, changing them probably won't cure your problem. Bad valve stem seals usually show up as smoke on start up. No smoke driving down the road. A puff of smoke after idling at a stop light for a minute or two.
The first thing I would do before changing parts is do a compression check.

 

My seals really don t look that bad to me, and my truck smokes the whole time it is idling , so I hope its not the rings, then it means a rebuilt job. I removed the number one spark plug back fast fall and it had wet oil on it, now I pulled it last week and it has dry black exhaust on it, which means its running rich. So my question is , if it is running rich would that cause the truck to smoke ?

 

When an engine sites for a long time the rings may get stuck in the piston grooves and not seal or control oil well. It may be worth getting can of seafoam and add it to the crankcase and put some miles on it. There was a guy a while back that was having issues with smoke - especially on one bank. He had pulled the intake to make sure it was sealing and replaced the valve seals. It still smoked bad. He ran a can of seafoam through it and the smoke disappeared as the rings started to seal. Worth a try anyway.

I have found that valve seal leaks may produce a puff of smoke after the engine cools and the engine will smoke more when decelerating when you have high vacuum that will pull oil down the guides. Unless the valve covers are filling with oil valve seal leaks often won't produce a lot of smoke at idle, for example. I said often so that mean that some may and some won't.

If you have gunk in the oil return holes in the heads that can cause the valve covers to fill with oil and nearly all seals will struggle under that condition. You may find that if the engine sits overnight it may not smoke when first started until the valve covers fill up. You may also find that it smokes a lot more on sustained highway drives where you are constantly keeping the valve covers full.

Lots of reasons for smoke but I'd start with the seafoam myself.

 

Blue smoke = oil
Gray smoke = Fuel
White smoke = water

 

Thanks for the replies. I when out today to put the value seals back on and discovered there is some short value guides about a 1/2 inch tall and the value are not loose . The intake value seal with the metal rings around it would not go over the guide , but I put the umbrella style and it goes over the guide and all the way to the bottom like it is suppose to. So I think I m going to order umbrella seals and put them on and see what happens , and if this does not help, I ll try seafoam. The value look good no crud anywhere and the drain holes at each end are clear. The smoke is more blue or gray color, I will look again when I get it started and check to see the color, am thinking it was more gray. I wish this website had a easier way to download pictures, If I can find a easy way Ill show some pics of the heads.

 

Ok one more question, I went by Napa yesterday and purchased value seals, they had intake and exhaust seals. The intake seals was umbrella that goes all the way over the short guide and to the bottom, and the exhaust seals were a short umbrella style and it will only goes to the top of the guide and not all the way down to the bottom, so should i return these exhaust seals and get the umbrella long ones ?

 

Just put them on, as soon as the valve opens it is going to push that seal up the valve stem and that is pretty much where it is going to stay.