8BA timing & temp rise under speed.

russcc

Well-known member
Running a stock 8BA, (8RT), in a light roadster. Under constant load about 40 to 50 MPH the temp starts to go up above 180. Let off a little and it drops right back down to even less than 180 with 180 tstats. I know the advance in the loadamatic dist is not all that it could be. Would too much timing create temp rise as I described. I ask because a friend in the EV8 club has a 33 with a built 59AB in it. He had an overheating problem at higher speeds, and found the problem was to much advance on the crab dist. Than you Fordbarners.
 
Usually over heat is from not enough advance not too much. Retarded timing makes them run hot.......

Would be curious to see what setting your friend had on the vacuum brake on the crab unit..
 
The simple answer is YES. Either too much or too little advance can cause excess combustion heat to be passed to the coolant rather than being used, as designed, to properly act on the pistons during the cycle.

Of course the coolant system and the gasket seal must also be considered adequate for the load placed on the engine. In this case it sounds like heating becomes problematic at very light loads so everything should be reviewed such as radiator capacity, coolant and air flow, as well as engine tune up.
 
180 is not a bad temperature , in fact it is a little lower than you like. If temp drops below 180 when fully warmed up, sounds like his stats may be stuck open.
Also,, what JWL says.
 
Thank you all for the advice. The radiator is a recent 11 fins per inch re-core with original tanks. The cooling system is clean, and the tstats tested ok, opening at 180.
I will pull back a few degrees of timing, see what happens, and report back. On the built '33, Dick said that he adjusted the advance back on the crab a little at a time, until it found the right spot, and the overheating at highway speeds stopped.
 
if the temp drops below the temp setting of the thermo I would look at it, thermo stats are supposed to keep the water temp at the designed temp of the thermostat
 
russcc i am having the same trouble now with 59ab in 46 coupe i can not pull a hill you can get hard on the gas temp goes right on up pass 200 :confused:
 
russcc i am having the same trouble now with 59ab in 46 coupe i can not pull a hill you can get hard on the gas temp goes right on up pass 200 :confused:

Helen,
I think you should start another thread so it don't get tangled up with this thread.
Your temperature rise is quiet a bit more than this guy. Is the engine stock? Is the ignition stock? What temperature does it normally run at? And so on.
Like I said start a new thread, it'll keep it fresh and not get muddled up with similar but not the same problem.
Martin.
 
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