Car still overheating after 11 blade fan fitted

[stevo96]

Hi All,

I recently changed my 5 blade fan over to the 11 blade thinking it would cure the car from overheating. It is still overheating, its just been running at 250 after 10 mins of driving (it was at 250 with the 5 blade). Ouside temp was 23C. Ive purchased an oil cooler but waiting for it to arrive.
Engine is a 2.7 1976 with CIS. No trombone cooler fitted or carrera cooler - any ideas? Anything I need to check?

Cheers
Steve

[Walko]

Steve
is it over heating whilst sitting in traffic or after a highway run??

Michael

[stevo96]

Its overheating whilst driving with no stopping or starting. Doing about 40mph....

[gtc]

Maybe check to see if the engine is running lean?

[stlrj]

Mice nesting in the engine?

[Walko]

Steve lets look at this logically
1 Is your 2.7 leaking a fiar bit of oil
2 When was the last time the motor was degreased to remove excess oil sludge on the cooling fins
3 Is the fan belt adjusted correctly
4 What is the oil pressure like when you are doing 40
5 Have you checked the oil level is correct

Michael

[stevo96]

Yes it has an oil leak from the back of the engine, top side.
Engine has not been degreased.
When I changed the fan I put exactly the same amount of shims on in the same order so fan belt is same tension.
Oil pressure gauge isn't working, it sits right at the top which I'm told is a problem with the earth wire..
Yes oil level is fine.
When fan was removed I checked for mice etc and around thd back-all clear.
I'm thinking maybe a thermostat issue or fuel mixture?...

[T77911S]

if you have a bad oil leak, that could clogg up the fins with dirt.
look at the engine temp Tstat

[Walko]

Steve as our motors get older the oil leaks will cause dirt to catch up and clog the cooling fins.
I would suggest that you thoroughly degrease the motor and check the thermostat at the rear of the motor.

When you remove the thermostat you make sure you use a new o ring as that may be the cause of the oil leak.

I have found that when you degrease the motor start from underneath and use the $2 pressue pack cans. I usually use about 4 to 5 of them when i degrease a motor 2 underneath and a few up top.
Make sure you let the chemicals dwell for a few minutes but ensure you hose the chemicals off the motor really well with water.

Hopefully this will assist

Michael

[schumicat]

is your engine mounted oil cooler getting hot? your thermostat may not be opening.

[Joe Bob]

Get a hand held pyromter and start checking components....

[stlrj]

Some have found nesting material on top of the engine including the oil cooler.

[quattrorunner]

I just added the complete fender oil cooler system to my 77 911s which already had the 11 blade fan. Here is my notes.
Before the cooler setup, I had 240-265 temps!!!! Maybe not as quickly as you though, more like 20 minutes in 100f degree heat. So I would be careful when and how long I would drive it till I got the cooler. After I got the cooler and lines installed, I knew and did see that it would take much longer to get to 210f, and it took probably half hour in 100f heat and never really did get there below 70f night time driving easy driving. But, in stop n go driving, it would eventually get hot again (230-340f). It would cool down to 220 after a while of highway driving. I got two 5.2inch spal pusher fans installed and haven't had a problem since, even in 110f heat the other day(it went to 225f).
My cooler is the one that our host sells. Pelican Parts - Product Information: PEL-TMP-9802
The lines and thermostadt to get the oil there are just good old lines off a wrecked sc, I did need some lines to connect oil tank and engine to the system and the whole project will set you back but it's what needs to be done to keep these cars cool in anything over 95f heat. Good luck.

[Brorag]

I've got one of these I'm not using.
you can have it if you pay the freight.
JD

[gordner]

Brorag, if he has no forward cooler the scoop won't do him any good, but I could sure use it!

[Sway Bar]

I would check your thermostat. Getting that warm after 10min in only 23C/73F even with some dirt and oil isn't normal - Oil isn't making it to the oil cooler.

[GLASEM]

Is your sump plate in the correct location?

Had a similar problem over heating problem after I changed oil.
I put the sump plate back in 90 degrees from correct.
After I reinstalled it with the drain plug on the left side of the engine....no more over heating.

One would not think this would be an issue till another Pelican pointed this out to me

Here's the link to my prior post on this question:

Over Heating 911 3.0

[jase007]

Hi Steve:

Have the same engine ('76 2.7L CIS, no thermal reactors, no AC) and no cooler setup. Mine gets hot but never over 230F or so. (have numerical gauge).

Things I have done:

1. 11 blade fan.
2. Seine Systems "Heet Sheet" on lower 911 Turbo valve covers
3. CO% properly adjusted (using exhaust gas analyzer)
4. Valves regularly adjusted.
5. resealed engine T-stat gasket, oil sending unit, on-engine oil cooler (clean fins), new CIS intake boots, etc...
6. degreased motor. (simple green and old tooth brushes work well after 1st pass )
7. restricted flow cam oil bolts (higher oil pressure to valve-train)

I too have a 3.2L carrera front fender cooler, hard lines, engine oil lines/T-stat, etc.. to install once I decide to swap out the heat exchangers to SSIs (additional oil lines required for SSIs and fender cooler conversion).

If I push it on the street, it gets hot. Traffic is OK for a while on a hot day but I avoid commuting in the car.

Cheers.

[sixbanger]

Grab a hold of the fan and see if you can turn it. If you can then the belt is loose. As the engine speeds up the belt will expand thus turning the fan slower.

[LakeCleElum]

My 2.4 ran hot. A little better after I pulled fan/alt and cleaned out the mice nest.

Solution for me was to add the factory trombone setup. Of course this includes hard lines, thermostat, etc. Rarely gets over 195 now....