Still running hot now im petrified

[brian bramble]

I posted last week regarding my 75 2.7 over heating and with sputtering and exhaust studdering and little back fires.. Per the forums recommendation , I put all of the engine tins and hoses back where they belong ( or at least where they were before the engine compartment fire) . This post wont make much since without the previous thread , but anyway... I took her out to see if the heat shields helped. It sputtered a little at first and stayed 210 ish. Then it got hotter and the hotter it got the worse the sputtering was.. Now I'm scared to death that I have don't critical damage inside the engine. Total panic. What's next compression test??

[Winter]

Have you pursued all the other suggestions made (in addition to replacing all the engine tin) in your first post? No mouse house, timing correct, air/fuel mixture dialed in, etc., etc.?

[blucille]

did you inspect for rodent nests behind the cooling fan, should be a quick and. easy thing to do, would effectively block the majority of the air flow across the cylinders

[Ian Comerford]

Do you have oil lines running along your sill (rocker)to a cooler in the front wing? If so is this getting hot? If not then the thermostat may be stuck. Once the engine is warm you should be able to place your hand under the rocker and feel that the pipes are warm.

[EC900]

Brian - you need to list everything you’ve done so far otherwise newcomers will just post comments with recommendations you already performed.

By everything I mean everything. Parts, repairs, pressures, settings, any removed parts, added new/used parts, compatibilities and/or modifications.

Sometimes posting a few photos can detect anomalies by pelican sleuths.

I asked previously what components were replaced if known and maybe by whom. Even the best indy techs can err. To wit; I had a 3” rubber hose knocked loose and missing on an L-Jetronic VW engine caused a slew of running issues. Replace 50¢ hose and problem completely gone. VW didn’t do smoke test just a keen eye found the problem in 10 minutes. 50¢ hose + dealer shop fee way before standard hourly rate charge was established set me back $20

So again, what was burned and why - electrical or fuel origin - full engine compartment consumed ? …and if any of the CIS was affected and repaired.

Also, besides the timing that was mentioned by others and wasn’t asked…are you running and certain proper spark plugs and wires used - if replaced? Coil, cap, points too and was timing adjusted yet? Where’s your idle RPM, and hard cold starting or hot restart?

Do a smoke test, this can help sort any vacuum leaks. Comp/leak down not necessary, no reason it would be relevant until spark and fuel is corrected.

Btw I suggest keeping the original post going and update your progress there so comments and suggestions don’t get lost or add confusion.

Good luck

[brian bramble]

Thanks again and again.

I scoped to fan area. Clean. There are no oil lines in the rockers. As far as the timing goes, it idols well and under high R's its top knotch. It's just when first accelerating after a stop and while under load in the low rpms. I've taken a bunch of pictures of the engine compartment and will post them after I get someone here to show me how. Also the air fuel adjustments ,I'm not real familiar with.

[brian bramble]

Ok , I will bring everyone up to speed and stay on this thread.

I've had the car for nearly 35 years and have been through a lot. I'll try to break it down as simply as I can
I bought the 1975 911s in 1988, from a guy who apparently drove the hell out of it. I was 24 and zero idea what I was getting into.
6 months later I had to have the engine completely overhauled. A Porsche guru who once was president of the Cincinnati PCofA. They did a very through job, even sending the block out CA to have the engine balanced and blue printed as well as timing chain updates. SS heat exchangers. fuel tank. The guy had a young apprentice to the bulk of the work..Later that guy owns a Porsche racing team (Wright Racing) . They only work on newer stuff now so I'm told or he would have the car as I type.
Drove fairly often for about a year before I did the Body work . That took about a year. Absolutely ran perfect for several years but mainly on perfect sunny days .. Perfect

FF to about 15 years ago. one of those old braided fuel lines split and I had an engine compartment fire.. The driver side got most of the damage.
I took her to a so call Porsche guy who completely messed it up.
Then to a different "EXPERT" same results but she ran a little and had a new muffler and he for got to put the "tins " back on.
So then I took a different approach and had the body work ,paint and interior done ,so the car would look like sometime other than a P.O.S.
Then I found a guy and his son that to Air Cooled Porsche restoration. That got it to where I took over..
New plugs, button, cap, 2 different electronic ignition box things. New wires the OEM braided ones with the ground wrap. Drained the fuel, put in a can of injector cleaner and have been trying drive her to wellness until I noticed the over heating thing.
I put all the tins back on and one of the hoses.

That is the shortest version I can do for a car Ive had since I was 24 and now I'm 61

sorry about being windy

[proporsche]

somebody should really look at you engine set up mainly the ignition timing ..i mean who knows 911 stuff

Ivan

[brian bramble]

Here are some pics, I'll try to send you more

[brian bramble]

[rwest]

First blush is that there should be an hose going from the top of the engine to the heat exchangers near the muffler. It would have also been routed to a blower fan and from that fan to the heat exchangers. Search blower delete and you should find more info.

I’m not sure if having that just blowing air into the engine compartment would steal air from cooling the cylinders or not. For the time being you could try duct taping something like a spray can cap over it to see if that helps.

[Lyle O]

Also, you mention that there are no lines running along the rocker (passenger side) to the front. I am no expert on '75s (I have an '87), but didn't all from that year have the looped-tube oil cooler in the front passenger-side wheel well (between bumper and wheel)? I checked the PET and it shows it, and it is not mentioned as optional. Could this have been eliminated somehow? It would for sure help in cooling...
If I have this wrong for that year, so sorry, but others can correct me.
Lyle

[brian bramble]

Thanks , here is some more Intel. She's a very very hard start. I haven't driven enough to determine hot start. Off then immediately restart, seams fine. I really don't recall if all of the hoses were hooked up when she was running great. I didn't work on her very much when she was running great but I know that the heater boxes have been rusted out since I had her.

Is the blower supposed run all the time? I know I don't remember that.

Thanks

[proporsche]

yup all the heater hoses should be in place -.Also can you take a picture of the distributor position how it sits ??
The blower is only runing when you pull your handles next to the hand brake
Ivan

[rwest]

Originally Posted by Lyle O

Also, you mention that there are no lines running along the rocker (passenger side) to the front. I am no expert on '75s (I have an '87), but didn't all from that year have the looped-tube oil cooler in the front passenger-side wheel well (between bumper and wheel)? I checked the PET and it shows it, and it is not mentioned as optional. Could this have been eliminated somehow? It would for sure help in cooling...
If I have this wrong for that year, so sorry, but others can correct me.
Lyle

No, they didn’t all get the trombone cooler. My 77 didn’t have one and I can keep the temps around 210F.

[rwest]

Brian,

Do you have a timing light and an air/fuel ratio tester or a local shop who could do the tests for you? That would pretty quickly rule out timing or lean running conditions.

Just wondering if you set a good light shining into the fan and then in the dark looked up from under the car to see if you can see the light coming through the cylinder fins. Not sure it would work, but might help rule out debris in the fins or on top of the engine.

Maybe this has been covered already, but do you know if your temp gauge and sender are working properly? Maybe get an IR temp gun and point at the sender to check?

[mikedsilva]

Originally Posted by brian bramble

Here are some pics, I'll try to send you more

Just blocking off that duct on the left should make a noticable difference to making sure the air will flow through the heads and barrels.

Airflow will take the path of least resistance and that giant opening is where the majority of it is going.

I would also check if your oil cooler has been obstructed on the top which would stop air flowing through. Leaves, debris, fur etc

As for the difficulty starting, well that's a whole other topic.

[brian bramble]

Thanks Guys
I really appreciate the input.
I don't have a timing light anymore and Sears is no longer in business.
I can get one .. The air to fuel ration things perks my interest , as that was my first
impression. Heavy on fuel burning off in the exhaust and working much much better on the high end makes since. But my fear is that when it gets hot the missing and coughing get WAY worse.
But it is my nature from owning this car , to go to the worst possible senerio .

I put a scope in the fan area and there absolutely no obstruction s or rodent dwellings. And the two hoses running along side of the rockers is for sure abandoned A/C lines.

Thanks again.

[brian bramble]

I truly appreciate all of the input, as I really want this car to run the way it used to. I can pick on all of the trivial stuff , and call it a "hobby" , as time goes by. But, I really want her to run perfect as I go along.

[proporsche]

Brian i will ask you again can you take a picture of the position of you distributor where it held by the nut and washers This way you kinda can tell the timing is off..