How hard to remove oil cooler on 72 911 with motor still in car?

[J.HK]

My car is running a little warmer than I would like and I was thinking of trying to remove the cooler and cleaning it up in hopes of improving cooling.


How hard is this in a 72 911? And is it even possible with the engine still in the car??

thanks

[GIBSON]

Taking the cooler off is not that big of a deal. My experience has been that cleaning out these coolers does not do a great deal to lower temperatures unless they are really bad.
You'll want to drain the oil, remove the air ducting shroud over the cooler ( I think it was 72 when they updated the piece that fits over the cooler so it can be removed easily), remove the engine sheet metal on that side, remove the heat exchanger on that side, remove the "S" hose from the oil tank, remove any sheet metal on the rear of the engine that attaches to the oil cooler and you should have access to the 4 bolts that hole the cooler in place, 2 from above and 2 below. Have a set of new seals (3 of them, 2 smaller, 1 large) ready to go.
There are shops that can properly seal up the cooler and clean it in an ultrasonic bath.
Check for previous posts on this subject, there are lots of them. You might want to wait for Wayne to get the server updated, the search could take a while at this speed...

[Jim Sims]

Before pulling off and cleaning the engine mounted oil cooler I would check/do the following: 0) ensure the fan belt has adequate tension and is not slipping, 1) ensure the top of the engine is sealed from the bottom to prevent backflow of hot air by ensuring the sparkplug wire seals (rubber disks) at the intake valve cover openings are in place and in good condition, engine sheet metal in place and rubber seal from body to engine sheet metal in place around outer edge of sheet metal, 2) that the heater ducting hoses to the heater boxers are intact and not allowing the fan produced cooling air to leak out the top of the engine instead of blowing over the cylinder and head cooling fins and engine mounted oil cooler, 3) using a pressure washer (like at a DIY carwash) blast any debris off the outside of the oil tank inside the right rear fender, and 4) remove the fan and alternator and check for and remove any debris (pine needles, leaves, mouse nests, etc.) under the shroud/on top of the engine. Cheers, Jim

[GIBSON]

You should do all the things Jim mentioned. Also, 72/73 cars without front coolers can run somewhat warm. My 73S, freshly rebuilt and with a clean oil cooler but no external cooler, can hit 200 on a warm day and 210 is not unusual. Things to consider:

1. does your engine oil temp climb to 180 and then level off for
a time before climbing? The oil thermostat will open at roughly
180 degrees sending oil to the cooler. A normally functioning
thermostat and cooler will result in a leveling off of oil
temps right around or slightly above 180 degrees.

2. on warmer days, ambient temps over 80 degrees, it is normal
to see the temperatures creep up over 180, especially under
load like climbing hills. A good, healthly system will rebound
and you'll see the temperature fall once you are on level ground or have less load on the engine. So thats another way of determining the condition of the engine.

3. test the engine thermostat by heating it in warm water with a thermometer and watching it open, hopefully at the correct temperature.

If you have no external cooler and you have a stock 2.4 motor, engine temps can easily be over 180 and still be fine. 200-210
on warm days is not that unusual and should not be harmful.
That's my opinion anyway.

[J.HK]

My car is running a little warmer than that I'm concerned that when it gets real hot here, 90's I'm going to have a problem. I was up at 210 when it was around 70 out.

I want to remove the thermostat but there is a sending unit that I can't seem to get out of the way. I think I need to get a very thin wrench to get to it.

I do need to replace one of the spark plug boots. Could that make much difference? I don't seem to think so.

Thanks,
J

[GIBSON]

J. To get that sender out of the way I took an inexpensive (Sears) combo wrench (19/17mm) and heated the center section with a torch and the bent an angle into it. It now allows me to get a 17mm open end wrench on the fitting and loosen it. Yes, you have to remove the sender and fitting to get the thermostat out. There are other ways to get that fitting out, a crows-foot wrench also works, I've just had good luck with the bent 17/19.
I'll post a photo of how it looks if you want.

I think I'd remove the oil cooler as a last resort. Try all the other possibilities first.

[pwd72s]

[QUOTE]Originally posted by GIBSON
[B]Taking the cooler off is not that big of a deal. My experience has been that cleaning out these coolers does not do a great deal to lower temperatures unless they are really bad.
You'll want to drain the oil, remove the air ducting shroud over the cooler ( I think it was 72 when they updated the piece that fits over the cooler so it can be removed easily), ....

Gulp! I hate to admit that the '73 has ANY advantage over the '72...but in this case it does. My '72 shroud is one piece, and the '73 owners get the seperate piece over the cooler....this pointed out to me one day by a skilled mechanic...

[GIBSON]

Thanks Paul, I knew it was one of the the two years, guess the 73's are a much better car!
'm thinking you might still get the oil cooler out without removing all of the shroud, I can't remember if you can get to all of the nuts with that shrould just loosened up and not completely removed.
I'm still not that certain that removing that cooler and cleaning it will make that much difference.....

[pwd72s]

Agreed. As long as the cooler is functioning, I don't see cleaning making a huge improvement. The ultimate cooling solution, of course, is to add the front cooler. But on a '72 especially, that opens up it's own can of worms...seen a good set of '72 front cooler oil lines lately? Me neither...

[Jim Sims]

J.HK, Also check your ignition timing, if advanced too far this can also contribute to overheating. Jim