Thanks for the questions, Dick. This weekend I addressed your concerns and
now can respond as follows:
1. when overheating started: I recall that after my valves were
adjusted for the first time after the compression/head/valve work, the guage
would creep past 1/2 to 3/4, but only at extended idle in hot weather. No
idle problem then.
2.and 3. : thermostatic vacuum tubing: THIS was the culprit...I think.
I pulled the vacuum hose from the distributor and did not notice the usual
rise in rpm from 850 to about 1200/1300. I pulled every vacuum hose and
connector and cleaned them with a carb cleaner (with the little plastic tube
high pressure nozzel). At the same time I removed and cleaned the carbs'
temperature compensators, after reading Moss Motors' carb troubleshooting
suggestions in their catalog. (I also had the problem develop this weekend
with the idle jumping to 3000 to 3500 when I bounced the throttle or put in
the clutch to shift. ) Now the idle is stable at below 1/2 when driving, and
1/2 to a little over at idle, and vacuum is again restored. The rpms also
are now back to normal when I pop the throttle, which I also cleaned and
lubed, although it seemed to be fine upon inspection.
4. radiator cap is rated for 13 lb.
5. I do not have a fan shroud that I can see, but I installed the abs
radiator duct from VBL last summer.
6. radiator was inspected and "okd" in late '97 in Tuscon, but it sat
until I picked up the car in late '98....it looks very clean on the outside,
and the coolant is not showing any signs of rust or discoloration. Should I
remove it and have it cored? Is removal a difficult job?
7. yes, the car overheated even with the air off.
8. I really noticed the idle problem and quick overheating after I
installed a new anti-run on valve and the temperature sending unit (near
thermostat). By the way, I also installed a 165 thermostat this weekend, too.
9, fuel lines were not in contact with anything hot.
10, I still have some run-on at 850-900 rpm, but not always...about
every fourth or fifth shut off now.
Thanks for the great suggestions, Dick. Any thoughts on why the car
ran hotter with poor vacuum? Or am I assuming too much, and perhaps the temp
problem was the thermostat all along? It still runs warmer now than it did pri
or to the valve adjustment...between 1/2 and 3/4 at idle, when before
adjustment it only did that with the air on on a warm dayand otherwise ran at
1/2. Do you think that the head work or the valve adjustment here caused the
temp rise? I recall that another 6packer (Tim Holbrook?) wrote about his
car's temp similarly rising after his first valve adjustment on his higer
compression engine. I wrote directly to him ( or whoever it was) then last
summer but got no response. By the way, my temp has never gone above the 3/4
mark at any time. Thanks again, Dick. Bob Pierson
Carmen Red '74
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