Thread: Delayed overheating problem

Tweet

Back to the task at hand

34_40:
Is this the bobbet style?



If so then that's what I have and I'll go grab a sleeve thermostat. Funnily enough, when I first started the engine it was overheating really badly. So I replaced the thermostat, but it still was overheating. So I grabbed the thermostat and stuck it in a pot of boiling water to make sure it was actually opening. Was really cool to watch, and it did indeed work. Installed the 4 inch spacer on the fan and it cooled much better just idling in my driveway so I left it at that.I will definitely try to get the fan in the shroud more, I think I still have that 2" spacer around here somewhere, I'll go get longer bolts today.


rspears:
I appreciate the guidelines for the fan dimensions, I'll make sure to get it within those tolerances. I also appreciate the advice on the electric fan, you just saved me a lot of time and money. That was also an interesting read, I guess another benefit of the mechanical fan is reliability (if it's set up correctly haha).


Mike P:
You very well could be on to something, the gauge is stock so it could be faulty. My reason for thinking it is overheating is that it goes to the redline, then slowly goes back down to the middle line (210) and stays there for the rest of the trip. That's also a good point about the flex fan, it was a pretty cheap fan and could very well be doing that. The blades flex out when at higher rpms because there is more air moving over the radiator right? What never made sense to me was that if this concept is aimed at cooling the radiator at more efficient rates, doesn't it "reset" when you change gears and the rpms drop? I have the old fan sitting in my parents garage in Oklahoma, I'll look into the cost of getting it up here.


firebird77clone:
I actually had to replace the radiator during the rebuild because the old one had a horrible leak in it. Before I rebuilt the engine I had the block cleaned in a vat at a shop so hopefully there was nothing in the system, but anything is possible, especially with my luck. Can I do a flush/service myself?


NTFDAY:
Timing is a bit of an issue right now, actually a pretty big issue. The engine I have I got from a scrapyard (2 bolt main 350 originally from a 1972 Chevelle, at least that's what they told me) and didn't come with the bracket for doing timing adjustment (you use a timing light to compare the harmonic balancer with the bracket right?). Although I did buy a timing light. So to adjust it I just turned the distributor one way until the engine stumbled, then turned it the other way until it stumbled and set it at the middle ground. I did the same thing with the air/fuel mixture screw on the carb. However, these are two separate variables that effect each other, so I feel like using this method on both is really difficult to get everything right. It almost seems like a system of linear equations.