evidence of engine repair?

[g sturgill]

The 73 911T I bought a couple years ago came from a family whose owner had died 6yrs previously. The car had no records nor did I have any forthcoming info from the owner's wife.

I suspect that some engine work was done over the course of its life, but how to tell what? After replacing the entire fuel system and converting to carbs, it now runs fairly well. The valve train, in particular, is quiet and everything seems and sounds good. I have noticed that the timing chain covers are sealed with blue silicone. I doubt that was a factory installation, right?

Any other things/changes that would be obvious?

Thanks, g

[Grady Clay]

g,

No, it is not original ‘blue silicone’.
Are there the external oiling chain tensioners?

Have you measured the cranking compression and done the cylinder leak test?
What is the oil consumption?
Any smoke on start-up?

Have you adjusted the valves, torque the rocker shafts and head nuts?
Have you inspected the sump plate and cut apart an oil filter?

What distributor number (Bosch or Marelli)?

Please post some pictures.

Best,
Grady

[g sturgill]

Hi Grady,

There are no external lines to the timing chain cover. I did a valve adjustment/check prior to start-up, and everything was right on or very close to specs, but I was thwarted in my attempt at re-torquing the rockers and heads. The a/c pump, combined with the CIS made it virtually impossible to gain access with engine in place. I did pull the sump plate and found nothing to get excited about.

The distributor is the original bosch, and from all appearances, the original braided plug wires were in place.

I've found little evidence of rounded bolt heads or missing parts. I did discover a couple of different size bolt heads when I removed the intakes to convert to carbs. The threads matched existing screws, but for some reason the heads did not.

The engine was very dirty. Oil had gotten into the air box and served as a dirt magnet after it had leaked on to the cooling shroud. Quite a greasy mess.

Still trying to figue out how to post pics.

I see you're from the front range, drive over the Meas to Cedaredge some day, and lets get together.

Regards, g

[Grady Clay]

g,

That all sounds good.
I assume you removed the fan shroud when cleaning.
Having a really oil/dirt engine is actually good because when cleaned, it returns to almost new condition.
The oil & dirt protected it over the years.
Is the A/C still on? Functioning?

Is this a Colorado car?
If so, who was the PO? I may know the car.


I still recommend cranking compression and cylinder leak tests now as that will establish a baseline for future diagnosis.

It is worth looking for that blue sealer between the heads and cam housings, at the cylinder bases, at the case through-bolts and the split in the case.
That may give you indication of prior work.

It is worth accumulating the special or modified tools to work on the engine.
DIY is very satisfying and, as you have found – easy.


When you installed the carbs, did you also install the phenolic insulating spacers between the heads and manifolds?
If not, this is a very worthwhile mod (standard since ‘71T).
These require replacing the twelve studs in the heads. There have been many threads on this.
On my carb cars, I installed two spacers for each cylinder (with a gasket between) for better insulation.


Your CIS fuel system was a circulating system, returning a lot of fuel to the tank.
You can configure a similar system where the fuel circulates past the carb inlets.
This has the advantage of keeping the coolest fuel to the carbs.

Your ’73 will also benefit by moving the fuel pump to the front suspension cross member (as ’76->).
All this will help prevent ‘vapor lock’ from our high altitude and (now) crummy gas.

Does your 911 have a front-fender oil cooler?
You will want that and a higher fan ratio for our hot weather and thin air.





Here is a little instruction thread on posting images:
How to post images (pictures) on Pelican
I think it is still ‘in date’.


I sorta straddled you last summer.
Our Sept. trip to Jackson, we came back through the NE corner of Utah and through Craig.
Our Aug. SW Colorado trip brought us back from Cortez, Telluride, Delta, over McClure Pass to Glenwood Springs.
This July we are going to the Gran Tetons & Yellowstone.
October may see us driving to RRIV in Monterey so long as I can make it a leisurely trip.
In assisting with this trip, several of us decided we need to see the area between Cedar City and Moab.
RRIV is Oct 14-16 but a lot more.

Best,
Grady