frozen heat riser

[Ken Harants]

My 66 corvette has a frozen heat riser, luckily in the open position. Can this be unfrozen without taking the heat riser off the car? Or, do I have to replace it.

[Joe L.]

Re: frozen heat riser

Ken------

I'd try using a good penetrating oil first. GM Heat Riser Lubricant, GM #1052627, is one of the best. Otherwise, you might try Kroil or PB Blaster.

If the above fail to free up the heat riser, I'd remove and replace it.

Another option is just to leave it stuck open as long as you're sure that it won't eventually end up being stuck closed. A permanently open heat riser is not such a bad thing. It might slightly impair choke operation, but it will make your right side muffler last a lot longer

[Ray C.]

Re: frozen heat riser

Hi!

As Joe stated use a good penetrating oil, with repeating applications of the oil. (allow enough time to work) I then used an air chisel with the pointed tip at low pressure and moved the butterfly pivot rod slightly from side to side. Once you have it free, continue to lubricate the pivot rod to prevent it from seizing up again.

Ray