Heat riser valve

XenonJohn · Post by **XenonJohn** » Mon Apr 20, 15 3:26 pm

Hi all,
Another problemette:
VE Valiant with 273 small block and Carter carb. Heat riser flap valve below exhaust manifold seized but spent ages getting it all working, used graphite lubricant etc. car left for a month and now very stiff again, will not turn on bimetallic coil easily.
Get impression this mechanism is fine if use car every day, but otherwise will jam closed most of the time sending too much heat to inlet manifold and carb.
Question:
If I fix the heat riser valve in open position (so inlet manifold warms up more slowly and exhaust goes down the right hand header like it should), will auto choke (operated off inlet manifold heat) open just a bit more slowly than usual, OR will choke just stay on all the time giving me a rich mixture all the time? Not planning to use the car in deepest winter / freezing conditions anyway.
This leads to second question, is it better to just convert it to manual choke? Had loads of cars in my youth with a manual choke and managed OK.

Thanks

John

latil · Post by **latil** » Mon Apr 20, 15 4:10 pm

Bin the lot. Remove the flap,weld the bush holes shut,block off the heat passage in the inlet and fit a manual choke. Someone will be along to give proper instructions soon.

Pete · Post by **Pete** » Mon Apr 20, 15 4:54 pm

Agreed.
First thing in the Skip.

I would not even fit a choke, more trouble than they are worth.

3 - 6 pumps of the pedal before start up and hold the revs up for 30 seconds - job done!

aussie pete · Post by **aussie pete** » Tue Apr 21, 15 5:01 pm

I also agree,......if you can get hold of another rh exhaust manifold, then bin the left hand one ( the one with the heat riser ) and replace it with the other rh one ( the castings are the same just one is machined out for the riser) ( mine are casting no 2843953 I have got one if you need it but do not know the postage ,...they are cast iron! )