I recently had the head on my 63 Valiant 225 reconditioned. New valves, had the intake and exhaust mating surfaces checked, manifolds assembled and then the manifold-to-head surfaces planed so all were flat. Also, had .075" removed from head in an attempt to raise compression ratio somewhat. Rebuilt the BBS carb, installed new thermostat, adjusted the valves to the .010 I & .020 E factory setting, fixed all the leaks in the radiator, filled the 'ol girl with coolant and fired her up. Would not hardly run; smoked badly, noisy and a whole lot of solid carbon particles on the driveway at the exhaust pipe. Exhaust pipe still the 1-1/4" stock size. After it gets up to operating temperature the engine settles down and idles as smooth as a baby's behind. After the initial startup, I readjusted the valves hot to the settings above. Now when I take off down the road the engine objects untill it starts to warm up then settles down. The temperature gage, an after market one with real numbers, approaches the 250 mark, then abruptly cools down to about the 190-200 range ( the gage is a little optimistic). After driving ~30 miles and shutting it off and letting get cold, I have to add 1/2-1 gallon of coolant. Replaced T-stat, water pump; both were OK, but being the excellant shade-tree mechanic that I am I wasn't going to embarrass myself by taking the water pump back. Besides I might need one in the next 80,000-100,000 miles. Still loosing coolant after driving short distances. There are no external coolant leaks any where to be found. No coolant in either the engine oil or transmission fluid. Today I pulled the spark plugs to see if they were wet; all were dry, but very black indicating a rich mixture. Also, I "sniffed" the air space above the coolant level in the radiator to see in there were combustion gasses in the coolant; there were none. The only thing I can think of right now is since the head was thinned by .075" the push rods are effectively longer which may adversely affect the angle in which they contact the rocker arms so that the valve lash setting I used is not correct. I'm out of ideas and its cold out in the drive way now. Any suggestions? Thanx for your consideration. Regards, RMDV.

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Carl Zeamer. an old guy, please be gentle.

I once tried that same test, resulting in a fair amount of confusion, and finally figured out that my nose is simply not sensitive enough to determine a result: the amount of combustion byproduct is so very small. There is a combustion gas tester available, it's a jar of blue fluid that changes (to yellow, I think) if combustion byproducts bubble through it. I was expecting to actually see bubbles, but the gas flow was so small that I couldn't detect even that. The fluid DID change color within a few minutes of idling, though. It did seem like a remarkably small amount of combustion gas leakage to cause a 1/2 gallon of coolant disappearing every 40-50 miles... that much I clearly recall!

- Erik

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Lots of early Valiants and Barracudas have crossed my path.
Also a handful of other toys for variety now and then.

Your cold start/cold run problems sound like nothing more complex than improper choke operation or adjustment. Which BBS are you running, is it the original 1963 type or a '64-up type? Easy visual ID: The '64-up units have a vacuum pot, that is a round metal "flying saucer" with a diaphragm inside and a vacuum hose connecting the back of the "flying saucer" to a fitting on the carb body. The 1960-'63 units have, instead, a piston in a cylinder with a link protruding inward through the passenger side wall of the air horn, connected to a hook on the choke blade. Both types of choke pull-off are adjustable, and both need to have an unobstructed vacuum feed to work properly. It sounds as if your choke pull-off isn't working.

What kind of "noisy" is the engine when it's cold?
Those numbers are on the high side. Your "abrupt cooling" is the thermostat opening. What thermostat temperature did you install? 180° is correct.
Repeatedly? Or just the once or twice? If it's just once or twice it is probably nothing more than air pockets (head, heater core, etc.) working their way out.
A 0.075" head shave is fairly drastic from the compression perspective on a stock engine, but is not enough to adversely affect the pushrod/rocker relationship.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

The "sniff" test was with the little instrument that changes color when combustion gasses are drawn through it. The "noisy" engine when cold has a rasping sound almost like valve timing is off, but it was not changed. Also, a lot of carbon comes out of the air cleaner until the engine warms up and the inside of the air filter is covered with soot. After the engine warms up it runs OK. Now, I let the car sit in the drive way and warm up rather than drive it and there was no coolant loss and the temperature gage did not go nearly as far before returning to "normal". The present T-stat is 190F, but the one it replaced was a 180F, both new when installed and both act the same way.

The engine runs smoth at first start for literally a couple of seconds then it starts to choke up. The BBS is the one with the vaccuum diaphram on it and all that seems to be working like it should. I have thought in my feable mind that possibly the pushrod-rocker angle was adversely effected
so that the lash setting was not letting the exhaust valve open far enough or not long enough. This was just something I thought of because nothing else seems to provide a clue. Thanx for the responses, I appriciate your help. RMDV

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Carl Zeamer. an old guy, please be gentle.

The "sniff" test was with the little instrument that changes color when combustion gasses are drawn through it. The "noisy" engine when cold has a rasping sound almost like valve timing is off, but it was not changed. Also, a lot of carbon comes out of the air cleaner until the engine warms up and the inside of the air filter is covered with soot. After the engine warms up it runs OK. Now, I let the car sit in the drive way and warm up rather than drive it and there was no coolant loss and the temperature gage did not go nearly as far before returning to "normal". The present T-stat is 190F, but the one it replaced was a 180F, both new when installed and both act the same way.

The engine runs smoth at first start for literally a couple of seconds then it starts to choke up. The BBS is the one with the vaccuum diaphram on it and all that seems to be working like it should. I have thought in my feable mind that possibly the pushrod-rocker angle was adversely effected
so that the lash setting was not letting the exhaust valve open far enough or not long enough. This was just something I thought of because nothing else seems to provide a clue. Thanx for the responses, I appriciate your help. RMDV

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Carl Zeamer. an old guy, please be gentle.

Really sounds like the choke pull-off isn't adjusted properly. Remove the air cleaner lid and start the engine from cold. When it starts blowing soot and running rough, push the choke blade towards "open" with your finger. If the engine smooths out, you need to adjust the choke pull-off.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.