Temp rises while under load PLEASE READ

[bigchillcar]

sure, remove the condenser if you don't plan on using it..take off the compressor belt too while you're at it if you haven't already..
ryan

[gliderguy]

BIGCHILL

I think you maybe right 70-75 seems to keep temp down 80-90 and she starts to rise more.

[gliderguy]

I love Pelican. I had a problem with a high idle after warm-up and with direct input and old threads traced it to a hole in my airflow sensor boot. My wife is getting jealous, spending to much time here. Hopefully Falls will make up for it!!!!!!!!!

[bigchillcar]

trust me on the highway speed thing. like i said, my car is setup like yours..i drive the freeway a lot and am always collecting 'data' and always know what to expect in terms of temps at any speed and outside temp..like clockwork my car stays in the 220-230 range at those speeds unless i get the urge to go faster and then it's up 10 degrees..get into the 90-100 mph range and my temp will hit 250.
ryan

[dougcl]

If you aren't using the AC, you might as well remove the condenser from the grille.

Doug
75 911S

[ianc]

Yes, removing the A\C condenser will make a little difference, but probably not significant.

One thing nobody else has mentioned is that the top of your engine might just be really cruddy. If the cooling fins on the cylinders and heads and the engine oil cooler (forward right side) are crudded up, the engine will never cool properly, no matter what you do.

It's a PITA, but with the removal of the alternator, you'll have good access to get in there and do some cleaning. Never know what you might find: rat's nests, old newspapers, etc.

Really helps to have a front cooler though: see what you can find used from an SC or Carrera... Good luck,

ianc

[911pcars]

"Other than external cooler any other suggestions to get the temp down?"

Well, if you can't install one by Saturday morning, how about starting the drive in the late afternoon or early morning when it's cooler? Got A/C? Need A/C?
- Recapture the refrigerant, then remove the condenser from the rear grill for slightly better air flow.

- An auxillary fan under the grill will help shove more air into the engine compartment if traffic precludes driving at speed.

- Disconnect and plug the vacuum retard hose. Reset the timing to 5ºBTDC. Verify you don't have more than 35º of advance @ 6000 rpm. You'll probably need to reset the idle speed after this.

- Make sure the fan belt is adjusted correctly. A loose belt won't allow the fan to push the correct volume of air. If you want to get fancy within 24 hours, connect the fan to a thermal relay circuit that automatically reverses the air flow when the car is heat soaking with the engine OFF (fan draws hot air out).

- Is 45 minutes the magic time limit before overheating? Then stop at 44, take a stroll and see the sights, have bite to eat. In other words, kill time. Repeat every 44 minutes.

- If you're really desperate to drive it even though it still overheats with the above mods, find yourself a garden sprayer, one with a 5 gallon tank if possible. Extend the hose another 8 feet and fix the nozzle end so it points toward the fan. Tape the trigger open. Fill it with water. Politely and lovingly ask your wife of 1 year (still doable) to pump when you give her the signal. Don't worry what passing motorists think when they see her pump. Trust me. The water spray into the fan shroud will work as well as this exercise in domestic compatibility. If she's a good sport, keep her. If she doesn't, then do the best you can, just like many of us.

RE: Oil. Don't rely on premium oil to keep the engine cool. It won't. It will, however, provide add'l high temp. protection against viscosity breakdown (no film strength = metal-to-metal rubbing). However, overheated engine parts expand too much and decrease oil/running clearance, especially the space between the piston and the cylinder (about "0.001 and 0.003"). The best oil won't prevent parts from seizing if they have their little minds set on it.

Have a good weekend and let us know how it went.

Sherwood

[bigchillcar]

for me it's a tradeoff..sure, at times i'd like to go over 90 mph on long stretches, but even though i'm a diy guy, i'm in no hurry to shell out $500 to install the cooler myself. if i can hang another 6 weeks or so anyway, it will start getting cooler..once winter gets here, you have the reverse problem - it isn't easy to get the oil warm enough. in winter, the ideal solution ironically is to have the 5-bladed fan..in fact there are those who swap them out for the change of seasons. i'm saving my pennies to overhaul my a/c this fall with new barrier-style hoses and new receiver/drier. arguably, i probably should make the oil cooler a priority, but until i do, i will drive smart..i'm making my sweating ass a priority instead!
ryan

[gliderguy]

Thanks!!!!!!!!!!!!! You guys are great!!!!! I will post pictures from the falls!!!!

[dd74]

Personally, I think you'll make it to Niagara with flying colors. Just drive conservatively, and your car will be fine. With all the stop-and-go-related high temps I put my old 2.7 through, it never shut itself down and stranded me.

[bigchillcar]

missing that 'ol 2.7, eh..david?
ryan

[exhaustfumes]

glider-guy:
don't forget to store your car in a secure garage while at the falls. Niagara is a pretty rough place these days.
you don't want your car to become "hot" in the other sense!!

joe with 77 2.7 with external cooler and mobil 1

[fireant911]

gliderguy,
I would first 'shoot' the sender with an infrared temperature measure device to verify that it is sending the proper signal. In my daily driver the sender went south and my temperatures at idle in a standstill was very normal and quickly rose to the red zone and soon as I was at highway speeds. After replacing the sender everything was normal.

[RoninLB]

you must get a front cooler for any relief. A used front cooler should be tested before install.

[MovOvr1]

yes becareful around the falls. A friend of mine just had (6 months ago) a Ford F250 taken from the falls area. With Canada just a bridge away. Never recovered.

If you don't go to the falls this weekend , come out and play with us at the PCA. it would be fun.

brian

[gliderguy]

Here is the gauge after 40 minute run.

[donstevens]

Glider Guy,

I see that as about 235F. Yes, that is hot but it is not killer hot.

I trust that photo was taken at idle as that oil pressure looks pretty low. You should have 10 PSI for every 1000 rpm even when hot. Fresh 20W50 will help this and that is something you can do before tomorrow.

Secodly, there was a lot of discussion about this with Bigchill, myself, patkeefe, and Grady Clay just about the 4th of July. Grady is a huge proponent of higher revs for more air flow over the cylinders. Do a search on "Grady" and I am sure you will find the thread.

Defnitely keep the revs up around 2000-2200 when stopped. Even when coasting. This not only keeps air circulation over the cylinders and oil cooler, it keeps the oil pressure up, and much better circulation of the oil.

Definitely keep the car at 65-75 MPH and the slower that you can tolerate, the better. The load on the car due to wind resisitance increases with the square of velocity. So 10 mph requires a lot more energy to push the car through the wind.

Lastly, Have fun.

Don

[dougcl]

I have witnessed higher oil temps, lower head temps at higher RPM, and lower oil temps and higher head temps at lower RPM. The comparisons are between 4th and 5th gear at 65-70. Temp differences are within 5F either way, and a nominal oil temp of 180F.

Doug
75 911S

[gliderguy]

Donstevens


This was at idle, and the pressure will go up, as I go thru the gears. Once at highway speed pretty much stays around 20psi.

Again thanks for the replies. I could take another vehicle, but what would be the fun in that!!!!!

PS to Donstevens, I am in Florida nov/dec at Treasure Island, just noticed you in Clearwater. No more hurricanes!!!!!!!

[jstobo]

20 psi is too low in my opinion at highway speed. You should be seeing 45-60 psi -15 psi per 1000Rpm. Surely at highway speeds you are not below2000 RPM. Either your sender is bad or your oil pump may be going. If the latter, may explain the higher oil temps. Or maybe you are low on oil. I'd get it checked.