the third belt that runs between my engine and the emmisions thingy (sorry, I'm not very technical) has broken on my 1980 F100 300-I6 truck, but the engine does not seem to be running any the worse for it........I'm not too sure what this emmisions thing does..truth be known I thought it was the alternator at first (until I looked down!) but I wondered if anybody can tell me what the ill effects of not having this belt would be??? It seems to feed gases back into the carb, but as my truck is exempt from emmisions testing, I wondered if it made any difference to run it without?

a second question......I just had to replace my starter motor, cause it was sticking and making a bad sounding noise, but it seems that its also chewed up the flywheel a little...it still starts ok, but I wondered if it would be a big job to replace the flywheel, and if it's likely to get any worse.

I really should junk this truck, but somebody gave it to me a couple of months ago and I'm really enjoying myself fixing it up...my new focus is soooo boring to own :-)

 

What you have is a smog pump or some call it an air pump. The idea behind it is to pump fresh air in through the intake or heads for a cleaner burn of the fuel. It also picks up unspent gasses from the exhaust or cat converter depending on the plumbing and mixes it with the fresh air for a more complete burn and a reburn of exhaust gases. The way these pumps are built causes a lot of drag and has to eat up some hp along the way. If you're not worried about emissions, I would remove the pump and the associated plumbing, plug off the holes and you should gain some hp and loose some weight at the same time. I somehow lost mine (clumsy me) when I converted from the I6 to my 351W.

'82 F150 2WD w/351W (orig 300 I6)
Slik

 

NO NO NO!!!!

I was afraid you'd suggest that very thing....

Listen, there are in's and out's to bypassing that thing, but many short sighted tricks will cause a LOT of damage later on.

If you want to remove the belt from it, fine. BUT:

The exhaust gasses will eventually eat the check-ball in the system, and make their way to the pump - causing even more severe damage. And one day you may need to have that sucker running to pass a smog check, right?

So you have to preserve it.

There is a large line leading to the rest of the air injection plumbing from that thing. The surest way to prevent back-gassing through the system is to cap that off completely (preferably between the check valve and the exhaust ports).

That way, it will all be safe from damage.

And me personally - I say leave all of that hardware in place, the simpler to reconnect it later on.

It might just save your ability to register the dang thing in the future....

 

I "lost" my smog pump and associated piping 3 1/2 years ago and haven't seen any problems yet (including passing my emissions inspections).

'82 F150 2WD w/351W (orig 300 I6)
Slik