Help please - 308 Smog belt broken

No problem. However he would fail a smog check inspection. heh heh. He is lucky the pump didn't seize. (did it and did the belt die to save the ensuing problem?) A pump seize sometimes stops the belt which stops the exhaust cam which stops the exhaust valve train which doesn't stop the pistons. Result - rattle rattle bang bang.
Onward
DOUG

 

I would check everything over carefully before proceding. As Doug suggested, the pump could have caused trouble at the cam belt, so make sure the car is running well, perhaps inspect the cam belt teeth carefully with a mirror and verify valve timing through the oil cap. The only other issue could be the air injection check valves getting cooked but in any event he should be okay until he gets home. Many cars had that pump removed and thrown in a box (or trash can) as a safety measure. Its been a problem and as Doug said, your lucky if the pump dont take out the engine. If the motor survived the pump failure I would suggest plugging the air injection downstream of the check valves, but I wouldnt necessarily delay my trip. I would fix it on the road if needed.

 

the system should already have a check valve, so there should be no worries of the exhaust gas leaking back up. otherwise the car will run cooler becouse your no longer "after burning" the unburned fuel. the air pump pumps air into the exhaust gas stream right at the back of the valve and inert combusted air with fuel mixes with active air and re-burns to reduce emissions, the down side is the extreme heat from this process. Alot of us rip the system out and remove the injection valves on the cylinder head, then plug the holes. the air pump is common to chevy's of the late 60's thru 70's, added to meet the US EPA requirement.

 

I have had that happen, and then I simply replaced the pump. I keep reading about camshaft issues following the pump locking up, but based on the small size of the belt driving the pump, it seems unlikely that that belt could stop or slow down a camshaft being driven by a toothed belt...when the pump seizes, the belt just slips on the cam pulley until it gets burned through, and then it falls off! It doesn't take long for this to happen, either.

 

I think the real issue is the air injection tubes/nozzles. With out the cooling air provided by the air pump, these pieces, which sit in the exhaust port flow, down stream of the exhaust valve, can deform and fracture. Removal after deformation, may require removal of the headers, to allow extraction of the deformed, cut off, portion. These nozzles consist of a perforated tube in the exhaust port with a threaded end to hold it in the head and allow connection of the supply tubing.

You will likely be ok for short term operation in this condition, but moderate to long term, it will revert to just an exhaust gas restriction, rather than and exhaust gas restriction with emission benefits.

Bill

 

actually they are hotter when the air is being pumped thru them, they deliver active air that ignites the unburned fuel mixture thus creating a mini afterburn. the long term problem is the cats will now operate colder and the extra fuel may melt down the cats.