[JUSTIN]

same drive home from work everyday. but sometimes when I get out of the car it starts boiling over. same air temp, traffic, a/c use. it seems that sometimes it just runs hotter. of course I have the idiot lights so I cant see the temp. I just judge it by the boiling over. 65 riv with a rebuilt 401 (5000 miles). the radiator has been recored, new waterpump, thermostat. the only guess I have is the fan clutch. can it work sometimes and not others. and how do I test it?<P>another factor is I have been fooling with the timing and carb mixture trying to get better than 8 mpg. could that do it? I have TDC now after being about 5 after for the last month. and I just leaned the carb up a little last week.

[65Catvert]

Justin--I hope you mean 5 BEFORE TDC, not 5 AFTER. My 65 401 Wildcat gets about 10-12 (which is an approximate guess) and runs fine at that setting, which is the spec I believe. Or does the spec come out to be 2 1/2 degrees? Not at home now to look but its halfway between 0 and the first line..I think you know what I mean.

[JUSTIN]

well now it is TDC so it shouldnt matter. I thought that the lines to left of TDC were AFTER TDC. isnt that advancing the timing?

[65Catvert]

As you are facing the engine from the grill, the lines to the left are before TDC. I don't think you will gain anything by timing it at TDC. You generally need to be before TDC by some amount.

[65Catvert]

I think your comment about jumping off the line holds the key. That is to say that driving style has lots to do with mileage. At this stage I don't drive mine much, but when I do I have a hard time keeping my foot out of it, its so tempting to zoom around. That will give definitely not good mileage, you can see the gas guage go down at each takeoff. Don't think they were known for good gas mileage--can you believe gas was around 30 cents a gallon then? Don't know about your cam, but you should be able to see markings on the block next to the major lines and I think there are small lines in between unless they are really messed up. Yes the far right is 0. Go right one line and see what happens. Can't tell you much more until I get home and look or check the manual.

[65Catvert]

Oops--I meant go left one line.

Boiling over into the overflow can is normal. But leaning out the carburator and running retarded timing can make it get hotter. Check the clutch fan by popping the hood when it is warm and running. Turn the engine off and see if the fan freewheels. It should stop fairly quickly if it is working correctly.

[65Catvert]

So back to your timing with the book and car in front of me--you made me curious. You should have 3 lines on the timing tab-0, 5,and 12--the last line is thicker by the way. Set the timing half way between 0 and 5. Remember to unhook the vacuum advance hose and plug it. Not a bad idea to confirm that dwell is at 30 degrees. If you've got more than 3 lines, then something is different. You should really get a manual if you haven't got one--too much info there not to have. The best $25 you'll spend. Good luck.

[JUSTIN]

I am just fishing for an answer to my bad mileage. it doesnt jump off the line at every stop light if I tune it to TDC. so I thought that might help mileage. I bought a total advance kind of timing light and tried about 25 total. but the mileage is bad so I thought maybe when it was rebuilt they put a little advance in the cam (1 tooth on the timing chain). if that is the case then I thought TDC would help me. does this make since?<P>when I twist the distribute clockwise the timing goes to the right. that is advancing it right? so If I have 4 marks on my block. where should the timing be set? maybe I have been doing this all backwards. right now its on the furthest right mark.

[JUSTIN]

A65catvert,<BR>You mention the last line as thicker (which is the last line? left most or right most?)<BR>is the TDC the one the furthest to the right or left?<P>if I twist the distrib clockwise , isnt that advancing it? the timing mark moves to the right (as I am facing the car). <P><BR>TOmsriv,<BR>as far as leaning out the carb and its effect on running hot. how can I tell if it too lean?<P>since this happens sporatically, then I am leaning towards the fan clutch. I will try the clutch test.