After working through a number of issues with my ’70 1.7 F.I., it is running great. I have a concern however with regard to whether it is running too hot. My weather right now in the Central Valley of CA (with the exception of rain today) is in the mid-90’s and breaking the century mark is not an unusual event. After idling for maybe 5 minutes and taking a moderate 2 mile run, when I shut it off it seems like the engine is putting out an inordinate amount of radiant heat. Timing I believe is spot on and there are no apparent rags, leaves, debris, etc. floating around under the tins.

I have not inspected yet but suspect the thermostat is not functioning. If I understand from reading various threads however, and although there are conflicting opinions, there should be no problem if the thermostat fails because the cooling flaps are supposed to end up in a default position as if the engine is already warmed up. Meaning the left flap is up and the right flap is down to pull air through the oil cooler. I have confirmed (by touch reaching through spark plug access hole) that the left flap is up (vertical). I am assuming (I understand the caveat) that the right flap is down in the proper position. How can I confirm that the flap is down short of removing the tin? I tried a mirror into the #4 plug hole (after pulling out a Bosch plug that the PO left there, but couldn’t see anything.

Sorry for being long-winded. Any help will be appreciated.

Keith

Kieth, do you have the lower air guides? How about all the tin to body seals?

Mike (Ceres)

oh yeah, do you have a high volume oil pump and/or the lower internal aluminum flaps in the housing that keeps the heat exchange from reversing heat into fan housing at low rpm's

Yep, got lower air guides in place, in fact all tin in place. Do not know anything about the oil pump other than the fact that the oil pressure light goes out. I know there is a flap on the left side in the fan housing, can't recall as to whether there is a flap on the right side.

Thanks for the reply Mike, you aren't all that far from Fresno so you know about the heat. I'll check on that flap.

Keith

How do you know the thermostat has failed? Have you tested it? Is it hooked up?
If the thermostat is not expanding as it should and the wire is in place your flaps will not open. If the thermostat is not hooked up and the flaps are in place they will already be open.
All this is meaningless however if you don't know about what temp the engine is running at. The engine will put off radiant heat at shutdown. Operational head temps at around 350 degrees and oil temps will be ~200. That is going to throw off heat even on a 90 degree day. Before you assume things are broken (unless you can see they are early broken) you need to get a functional engine thermostat. Mainley sells a dipstick thermometer that gives you oil temps, though you have to get out of the car to read it. It's a start.

So, is the thermostat on the car hooked up and the wire going to the flaps?
Zach

What Zach said. You should check the wheel the cable goes around for binding also.
Get some more acual temp readings, maybe a cht or even an oil dip stick gauge

I haven't confirmed failure yet but intend to. The cable is hooked up but I am making that assumption (thermo failure) because the flap on the left is in verticle position when cold. Also, there is a degree of paranoia because it seems much hotter than I would think it should be after such a short driving time. After posting I did see a write-up on the Mainly dipstick and am going to pick one up for piece of mind. That and as stated confirm the status of the thermo.

Thanks for the comments & suggestions guys.

Keith

...I just pulled a 1.7 apart to find that the left side flap (as facing the engine from the front) was re-installed wrong by the PO or someone at some point.

The stuck the damn flap under the tin lip somehow and it never moved

So, use the KISS method here as well.

I'm sure your PO was much smarter than mine.

I did that to my own car. Its not hard to do, especially if you are moving tin around with the engine in the car. I am pretty sure I pinched mine when I pulled the doghouse with the engine in the car, and then tried to wiggle it back into place.


Which left side? Left and right depends on where you are looking from. Please say drivers side or passenger side.

On the drivers side, it should be vertical when the engine is cold - its correct. The flap is blocking airflow from the fan. As the thermostat expands, the spring on the flap axle opens the flaps. When the flap opens it swings UP.

On the pass side the flap does not fully close when cold. It opens DOWN and creates a forced air guide for the oil cooler.

Either way, neither of them should be horizontal when the engine is cold, though the passenger side flap tends to be sort of diagonal when cold - at least on my car.

Zach