Hello and Happy New Year, Noticed that my truck never had a Heat Riser Spring and thought I purchase one over the holidays. Once it arrived I jumped at the chance to install it. However I noticed that when the engine is good an hot the Heat Riser never flips to the Off position. I installed the new Spring (btw Heat Riser Shaft moves easily) in the slit on the other end of the counter weight. The spring fits snug on the shaft. I did look over the manual and mentions to not over tighten the spring and only give it 1/2 a turn so the one end rests up against the manifold peg. So when I installed the spring, I have the Counter weight in the HEAT ON Position, I slide the spring through the slit on the shaft and where I can then apply some counter clockwise pressure to the spring to slide it past the peg. All looks exactly like it is pictured in the manual, however when I take the truck out for a drive (3100 53 Chevy Truck with 235), the heat riser stays in the HEAT ON position. When I park it back in the garage to look at the engine, I do notice the Heat Riser jiggles a little like it wants to turn off, but never does.. Any suggestions? Here is some pics that I took:
That's interesting . You're saying that when the engine is hot and idling you can (!CAREFULLY!) push the bob weight over with a finger and when you remove your finger it'll flip back to the up position ? .
Exactly. It springs back to the heat on position. I watched it after I took a drive the other day and sometimes I can see it flutter as if it wants to kick over to the heat off but never does.
That's why I asked when the engine is idling ~ I seem to recall new bi metallic springs not having quite the correct thermal properties . As long as it opens when you goose the throttle and you're positive you've tried flipping it over, etc. etc. it'll do no harm, just try to remember to unhook it come late Spring ~ now you know why the slotted shaft was pinched shut when new
Btw, Nate just a followup.. Took the truck out today and yes you are correct.. Everytime I goosed the throttle the heat riser flipped over, but will close when I let up on the gas.
That's good, I await to hear if you have vapor locking issues this Summer . If so, maybe try the low pressure (2 ~ 4 PSI) fuel pumps I mentioned elsewhere, I see O'Reilly's now stocks them in the Hot Rod section . I bet Farm & Tractor Supply places sell them *much* cheaper.....
