Temp rises while under load PLEASE READ

[gliderguy]

I have read ALOT of threads trying to research this out. 76911s

no thermal reactors, no oil cooler up front. Most of the threads I

read say there operating temp rises sitting in traffic. My temp

stays normal until I get on the highway then creeps up. If I really

get on it, rises quickly. Does this point to anything? Found

threads suggesting to lean, tried adjusting that. A little under

the 250 mark or third line. PLEASE any suggestions will help!!!!!!!

Newbe please have patience!!!!!!!!!!!!!!!![

[gliderguy]

Anything you can throw out I will try.

[gliderguy]

Maybe it late no response Here is a pic of the girl that is overheating. If you dont have sympathy for me then do it for her!!

[dd74]

I had the same "problem" with my 2.7, but I didn't have any ill effects from it. In fact, the hotter the engine became (to a point), the better it performed. I didn't have an external cooler, either, which in retrospect would have been a good investment had I kept the engine.

Regardless, I'd easily rise up to 250 on a normal drive. I think you should become alarmed if it creeps up to 260 or so. At 270, just pull over and let the motor rest. Temps that high won't kill the motor, but they're not good for it, either, especially if it's a magnesium case. You might notice a loss in power at 260 or so.

[dd74]

I guess what I'm saying is, you should have an external cooler installed. Oh, and you mentioned "leaning" the mixture out. No, I think you want to richen it to give the engine added cooling.

[gliderguy]

It is my one year anniversary on Saturday and wanted to take the wife to Niagara Falls {3 hour drive} I have been dealing with several issues and solved others, but this was still haunting me. I have not driven her more than 45 minutes at a time. Other than external cooler any other suggestions to get the temp down?

[gliderguy]

Correct I meant that others have said if it is lean it would run hot.

[grant lyon]

11 blade blower fan or the 5 blade type?
With the 5 blade, no oil cooler and heavy load (hill, hard acceleration) it didn't take much for mine to heat up in hot weather. With 11 blade fan hot weather is less of an issue. With 11 blade fan and front cooler, no issue at all.

[911pcars]

US '76s have thermal reactors. Engines with these run notoriously hot, that along with a 5-blade fan, retarded ignition timing and lean mixtures, all for emissions, take their toll on the cooling system and engine longevity.

Since yours no longer has the reactors, it's probably the hot weather, the other '76 engine specs and a lack of an external cooler keeping the engine hot.

The long-term prognosis includes a fender or front-mount oil cooler, 9-blade fan and correct ratio pulleys; to a minor extent, retime engine and reset fuel mixture.

Sherwood

[dd74]

Well...maybe you could try using heavier oil. Richen the mixture, as I said. If you have a/c, think about using it as little as possible. I still wouldn't worry too much until the temperature gauge closes in on 270. Once, when I was a newbie, my 2.7 got up to 300. It still ran, though, and ran well. But I don't at all suggest this.

If the engine "pings" under load, that might be something to consider. If this happens, go easy on it until it can cool down; don't rev it out.

[bigchillcar]

glider,
my car is setup like yours..2.7, no thermals, no aux oil cooler. i typically see 220-230 on the freeway if i keep it around 70-75 on these 90 plus degree days. if i start to drive 80-85, i will see temps rise up to 240. the only time i ever see the dreaded 250-270 range is when i've been caught in traffic, hence little airflow in the rear across those hot cylinder heads.

what oil weight are you using? i would recommend a 20w50 weight..this multi-weight is good for heat..like a true 50 weight when it's very hot outside and you'll need this extra protection in your car. i assume you have the 11-bladed fan..you definitely need this. there are upgrades for the fan you can even do which involve replacing the crank pulley with a different size to make the fan turn even faster. but by far the best bang for your buck for you or me will be the addition of the aux oil cooler. if you aren't a diy guy it won't be cheap to add the extra thermostat, extra oil lines, cooler, fan, etc. but it will probably drop your average temps when hot by 30 degrees..a huge difference. i have a/c too so that complicates the issue as well, as my condenser is in the rear deck lid..the same rear deck lid that the fan is also fighting for the same air through.

other things to consider as i think your car seems to be running slightly hot even for its setup is whether your oil temp sender is functioning properly, whether or not you have gunk in your engine oil cooler or whether you have debris under the shroud on your engine interferring with cooling. anyway, this is a start for things to consider. good luck, pretty car!
ryan

[dd74]

Originally posted by 911pcars
Let us know and we'll proceed with the long-term prognosis.

Sherwood: he says he has until Saturday. Maybe he should take a different car up to Niagara.

[dd74]

Glider - you are using the highest octane fuel you can find, right?

[gliderguy]

She does have 11 blade fan and no thermal reactors. Another suggestions was thermstat, in the rear right fender well?
Thankyou for the suggestion and keep them coming. I really want to take it to Niagara on Saturday!!!!!!!!!1

[gliderguy]

oh 20- 50 oil also

[gliderguy]

93 with octane boost!!!!

[dougcl]

Glider,
180F should be your target temp.
Doug
75 911S

[gliderguy]

What if I remove the Ac condensor blocking the air flow. I never use air any how. Effect on operating temp?

[bigchillcar]

glider,
i really don't think your car will exceed that 240 mark if you remain in the 70-75 mph range up on your trip with ambient temps in the 90's. avoid prolonged time in traffic (actually that's always a good idea with these cars, especially if you have no auxillary oil cooling). your car and mine are realistically 'temperature-limited' on extremely hot summer days without extra oil cooling..just drive accordingly and anticipate it until you can upgrade some things..
ryan

[gliderguy]

Would removing ac make a difference [I dont use it anyhow}