Fitted 11 Blade Fan - Still Too Hot!

[OZCarrera3]

Hi Guys,

You might recall in my last post I was thinking of fitting an 11 blade fan and then failing that, an oil cooler to try and solve my temperature problems.

Well, fitted the new fan and there has been little change in the running temperature (Still around 105C/220F) around town. Can't quite afford to do the oil cooler at moment and wondered if there is anything else I can check/do in the interim? My mechanic is pretty keen for me to fit the oil cooler (which I know is a must if I want to track the car), but I am concerned as to why its running so hot just with general running around.

The tune of the car is fine, just spent $600 on a tune up and work on the CIS.

Anybody got any ideas?

[RoninLB]

Originally posted by OZCarrera3
but I am concerned as to why its running so hot just with general running around.

?

I've noticed that many guys almost lug the engine around town. better to keep the rpms up in a lower gear than lug in the next gear IMO..........Ron

[Jim Sims]

Well the easy things to do are ensure the timing is correct and that all the rubber seals and air hoses associated with the engine are intact and in good condition. Check the spark plug wire seals and rubber sealing flap around the perimeter of the engine. Ensure the heater system air hoses and ducting are in place and not leaking. Is the air intake grill on the engine hatch clear of debris?

Next is to ensure the exterior of the oil tank and bottom of the engine are clean to promote heat transfer to the air. Increasing in difficulty is removing the fan and alternator and checking the top of the engine for air flow blocking debris. Moving on to more difficulty is removing the engine mounted oil cooler and cleaning it - especially the air side. This often requires at least a partial engine drop. My next suggestion is cleaning the cylinder and head cooling fins of oil and debris but to do this properly requires dropping the engine and removing the induction system and fiberglass shroud. If you get this far, check the sheet metal baffles around the cylinders and make the factory suggested modifications if thay haven't been already modified.

Ultimately you will want to fit an external oil cooler.

Cheers, jim

[john walker's workshop]

get a larger crank pulley, like from a 79 SC, and be sure the top pulley is the small one, like a 79. earlier cars had a larger top pulley. the fan and pulley have to each be the small pulley type, as you can't use a small pulley on a large pulley fan. more air volume=more cooling.

[Jack Olsen]

The tune of the car is fine, just spent $600 on a tune up and work on the CIS

Was it running hot before the recent work?

[cyprusx]

Not sure but I don't think 220F is too hot lugging around town based on previous threads... Is it?

[OZCarrera3]

Thanks for the hints guys, will run through the easier items of this list today. I think I will probably then have to bite the bullet and get the oil cooler.

Have been told the pulleys are the optimum sizes and when running around town usually keep the revs in the 2,500-3,500 range (love the sound!). Will take her for a run through the moutains tomorrow and see if it gets as hot as in previous runs.

Thanks again guys.

[1fastredsc]

yeah dude, 220 really isn't all that bad. My sc before i took it apart was running at 235-240 and was running lean. If you don't have a decent front oil cooler, than 220 sounds normal. Could be wrong though.

[RoninLB]

I'm not saying 220 is OK or bad.. but my 2.7 does 220 at
75-85mph in 110degF desert heat........Ron

[Argo]

Ronin - I'm doing some research on cylinder head temperatures and you seem to be the go-to guy in this area. What were your average CHT's on that desert run (and for other driving situations like around town, cool days, etc.) I've searched the bb pretty extensively and haven't found much info on CHT norms. TIA

Argo
88 Targa

[Langers]

Well you do live in Queensland, and if it's getting too hot now, then it will certainly be too hot in summer. I'm surprised the oil cooler wasn't fitted a long time ago. My father had the 11 blade fan and oil cooler fitted on his '77 2.7L as a matter of course when it was new. That would cretainly be the best solution, if everything mentioned by the other posts checks out ok.

[RoninLB]

Originally posted by Argo
Ronin -
What were your average CHT's on that desert run (and for other driving situations like around town, cool days, etc.)

Well it's a stock CIS. so that's a "fixed'.. higher compression, more hp, etc should have a CHT impact.. so what was interesting is that CHT hardly moved in the desert as the oil temp rose. and the only very accurate CHT I have now is around 240deg +-2deg at 75mph on 75deg midnite rides.. reading the old analog CHT from the desert ride registered a rise of about 20deg from 70deg ambiant temps. But this is with adjusting the speed to get the cooler CHT. so maybe instead of 85 I only did 75mph. The CHT is a great tool.. it'll let you know how to adjust gearing and rpm on mountain rides, when warming up the car, I even use it for
cool-down info.. ask me later when the car gets rolling again because it'll have E-cams and carbs.. should be interesting.....Ron

[Argo]

Thanks for the info - I just installed a VDO CHT gauge and I'm trying to get a feel for what normal CH temps are. So far it seems like 225 - 275 is the range, depending on speed, ambient temp, etc. I'll be interested to see your numbers when you get going again.

Argo
88 Targa

[amk]

Sheldon, mate, just for you I did a little research to see how hot I could get my C3… any excuse to take her for a burn

I took her for a 45 minute drive around the city and north shore. Temperature in Sydney was about 20C. Nothing like cruising over the harbor bridge on a sunny day with the car sat on 5,000rpm in second gear, throttle response is soooo good and she’s soooo noisy. Anyway, traffic was pretty heavy, most of the time I was plodding along at around 4,000rpm in second, I managed a few 6,500rpm take offs in first gear. Typical speed varied between 50km/h and 90km/h. Over the first 10-15 minutes the temperature worked up to 80C, over the next 10-15 minutes the temperature worked up to just under 100C and sat there for the rest of the drive.

I’d imagine it was a bit hotter in Brisbane when you recorded 105C, only other difference between our cars is you've still got the air-con. Hope this info helps in terms of getting an idea of what’s a “normal” temperature. Let us know how hot you get on your run through the mountains.

Regards,
Andrew.

[RoninLB]

Hey Argo

forgot to mention
that the CHT rises immediately
so maybe 5-10min before oil temp will begin to rise

[Langers]

amk,

Whereabouts in Sydney are you? Just so I can add you to this thread:

http://www.pelicanbbs.com/posts/94639.htm

(that link may not work for you...the main BBS server is down so I went to the backup server to get the link)

Klaus

[SteveF_911]

Come on Sheldon it has been pretty hot up here, my car even got warm on the way home from the motorkahna on Saturday. Although I was rushing home to see the grand final.

It is the first time I have ever seen it get hot on the freeway. I think it may have something to doo with the extra low humidity we have been having over the last couple of weeks.

I will mail you through the photos when I have a chance.

Steve

[amk]

Hi Langers,

I'm in Cremorne. The link seems to be working so I added myself to the thread. Thanx.

Andrew.

[OZCarrera3]

Andrew,

Thanks for the research, bet it was real tough driving around North Sydney and the Harbour Hope you didn't get any 'photos' while you were at it! Have noticed that it does take a lot longer to get to 100C now the fan is fitted.

Steve, yeah might have been jumping to conclusions yesterday, will still take Jim's advice and check the items he mentioned. Will keep an eye on the temps over the next week or two and then get some more info from you on the oil cooler we discussed on Saturday.

Had a great time at the motorkhana, looking forward to seeing the pics! Had a couple of runs with Ed in his 996 - what an awesome car!

Cheers,

[SteveF_911]

My car got to about 105 an the way home which is about what it gets to on the track.

I was just too upset over how much quicker Fart was in my car.

I will be setting up a course in the drive ways.

BTW your car looks good.