Engine: Heat riser valve ‘50 champion

[Flthdchamp]

Hello all,
My vehicle is missing it’s thermostatic spring on the heat riser valve. Besides it’s cold weather starting applications, are there any performance issues that can arise with the spring missing? I’ve read many people wire them open or remove them entirely. The valve moves freely and is not frozen.
thx,
Jim

[NCDave51]

Not so much for starting but idling, right? At a cold start there’s no hot exhaust gases to really heat it up that quickly for starting.

Vapor lock or fuel boiling could become an issue if you left it constantly diverted upwards is what I could imagine.

I believe replacement springs are available; doesn’t have to be from Studebaker.

[Flthdchamp]

I agree- it helps divert heat upward until engine reaches the temp when spring tension relaxes which is the default closed position for the valve. SI has replacement springs and I may do that. I was just wondering if a tension free valve , being loose like that , couid cause any performance issues on acceleration, etc

[NCDave51]

It won’t move under vacuum, if that’s you’re worried about. The counterweight is pretty heavy to overcome.

[Flthdchamp]

OK thx, I’m trying to diagnose an acceleration from stop issue ( feels like a bog, very slow off line when clutch released ) I’m having that doesn’t occur until the car is warmed up. I thought the heat riser may have been to blame. I’m going to
put a vaccum guage on it this weekend to try and figure it out.
Fuel pump has tested good, timing is set, all
ignition parts, fuel filter and vaccum advance are new. Engine runs very well, compression tested at 120 on every cylinder.
only thing I can think of is some sort of vaccum leak or fuel mixture issue? I pulled plugs last weekend and they looked good ( light tan color)

[NCDave51]

Do you have the OEM heat shield above the fuel pump/ below the carb bowl?

[Flthdchamp]

Yes, I installed it last weekend but haven’t driven it since so could have been the reason. I’ll find out soon. Is that a fuel symptom that occurs without the shield?
the acceleration issue I’m describing occurs after just a few minutes of driving.

[doofus]

Does sound a bit like a carb issue,float level might need tweaking up a bit. when cold choke hides this issue. also a hanging power valve piston. i would check the float level first. Luck Doofus

[Flthdchamp]

Thx I’ll check that