a bit of help with '73.5T

}{arlequin · }{arlequin's Garage

I noticed that there are two hoses on the left side of the fan (looking from the back of the car). They are located behind (to the front of the car) the distributor. They seem to be attached to the cooling shroud. Where they join the shroud, they are sitting on top of the nipples rather loosely. Poking around in there, they come off very easily. Is that a problem, or are the hoses just for venting?

Thanks,
dave.

Jim Sims · 05:40 AM

These are the the hoses that purge the charcoal cannister located up in the front trunk by the fuse panel. One hose should attach to a metal nipple on the fiberglass engine air shroud and the other should attach to a plastic nipple or nozzle on the driver's side of the air box just above the three driver's side induction runners. The line from the shroud provides a source of pressurized air to blow fuel vapors out of the charcoal cannister and back through the other line to the air box where they are inducted into the engine and burned. The hoses run to the center tunnel where they transistion to metal lines which come out just ahead of and behind the pedal cluster in the driver's foot well. There they go back to hoses which cross over to the left and pentrate the bulkhead ("firewall") and run into the front trunk and then to the charcoal cannister. Someday this system may have to be intact to pass an emissions visual inspection but for the time being I'd just plug the nozzle in the side of the air box and on the engine air shroud and secure the hoses. My son has a '73.5T so we are becoming familar with the car. Jim

}{arlequin · }{arlequin's Garage

Thanks Jim,

That was as perfect an explanation as I could have hoped for. One more reason to keep looking for those factory manuals.

dave.

Sunroof · 07-10-2003, 05:25 AM

I had the same concerns several years ago when I bought the car. I made the mistake of taking the hoses (their are two - one large and 1 small) that attach to the black metal canister in the trunk. By taking them off, when I fueled up to high the trunk would stink up and pass into the passenger compartment. Attached to the cannister as well is a clear hose that in mine wraps around in front of the spare. That is an intake hose. Make sure all these hoses are attached. Because the hoses were so brittle and cracked, I cut them as they came into the engine compartment at the firewall. I too plugged up the two "nipples" at the air box and shroud. I did not plug the hoses as they came into the engine compartment to allow for trunk vapor ventilation.

This was Porsche's first stab at emission control and compared to today is as primitive as a stone axe! Your adding abit more dirty emission into the air, but otherwise blocking those "nipples" will not impact anything. Just make sure the plugs are secure so they do not come off and get caught up somewhere. I used pieces of the old hose, epoxied in a plug (wood plug) and used a small clamp to hold it on the "nipples". Free artistic license here..

Welcome to the 73.5T world................

Regards
Bob

}{arlequin · }{arlequin's Garage

Yes, I believe I will be keeping the trunk set up "piped" as is. As far as the nipples are concerned, I'm sure I will find a way to close them off. Again, thanks to all that helped. Looking forward into delving into the T and its systems.

dave.

Sunroof · 07-10-2003, 09:07 AM

Good Luck Dave.
Just remember that many 73.5T parts also are on the 1974 911 and the parts houses require....CALIFICATION of the model year.

I will pass on a few helpful suggestions brought to me by three wise men.............

. once a month or so add Marvel Mystery Oil to the gas (10
ounces per fill up). The 2.4 seems to love it.

. keep the oil dip stick level to no more than 1/2 (between min.
and max)or the oil will run back into the air box (it gets messy).

. I have installed the Heet Sheet and the Cooler Collar and the
2.4 never overheats despite a clogged external thermostat.

. Change your fuel filter more then whats scheduled if your tank
is original.

. Swepco Works wonders in the 915.

Regards
Bob

Hockey fan · 07-10-2003, 09:26 AM

Bob,

Thanks for the Marvel tip. I'll try that in my car. Also getting used to explaining how and why my car is a 73 and a 1/2 to parts counters!

Jeff
73.5 T sunroof coupe

}{arlequin · }{arlequin's Garage

I was considering the "cooler collar" for the oil filter. My car has the heat exchanger passages blocked off (no ac) so 100% of the air blown by the fan is used for cooling. I was sworn to that the car never reaches over 210 (temp), and it runs stock, w/o the external oil cooler. Maybe 240 on a hot day at the Glen. We'll see how that goes.

I've never heard of Marvel, but I'll look into it.

I'll give Swepco a try since I'm having trouble (occasionally) with third gear. Could be b/c I'm so used to the foolproofness of a close ration Integra shifter.

Sunroof · 07-11-2003, 05:12 AM

Marvel mystery oil has been around since the early 1900's. Many on thsi board have provided testimony to its lubricating qualitites from aircraft engines to army tanks! My mechanic who started his career with the older models highly recommended Marvel every fourth- fifith fill up or so. A buddy of mine in the marine industry uses this stiff like a religion in his diesel engines. So many voices cannot go wrong. It a beautiful "red" that looks more at home on pancakes then in the engine, but thus far after two years of use (I bought the gallon size for $$$ savings), the engine continues to purrr.

The 2.4 never had a reputation for overheating, but even with my AC on during the hottest summer days, I have seen the guage go over 220, but never exceeding 230. If I replaced that external thermostat, I believe it could do better, but the cooler collar and heet sheet is enough for now to take the edge off.

I highly recommend the cooler collar for the few bucks it costs. It will relieve about a needles width of heat off the guage. The heet sheet just adds insurance for the valve train from exchanger heat.

Swepco goes with Porsche transmissions as bacon with eggs!
It reduces heat and its lubrication qualities are excellent.

Glad to help a fellow "T" owner out.

Bob

}{arlequin · }{arlequin's Garage

Do you have to remove anything off the car to install the heet sheet?

muddy · 07-11-2003, 05:55 AM

After removing/disconnecting/plugging the fuel evap system, are there any other effects besides emissions? My system is still intact, with all hoses connected, charcoal filter, expansion tank in the left front wheel well, etc. I think I'm going to keep mine as is, as long as it's either 1) working or 2) not working AND not screwing something else up.
Chris
73.5T

Sunroof · 07-11-2003, 06:13 AM

Heet Sheet is simple to install. The sheets bolt on to the valve cover with four bolts...piece of cake. The sheets ride about a half inch or so over the valve covers that acts as a cooling barrier.

Muddy...........
No problem with emissions here in Atlanta as the car is too old to be checked through the Georgia Clean Air Emission Program. Gotta wonder if it would even pass emissions these days!

Keeping the system intact cannot hurt anything as long as the hoses are secure and no leakage is going in the trunk that makes its way into the cabin. If my hoses were not so brittle and broken I would have just left it alone. I might as well be driving a 1955 Chevy!!!!!

Bob

muddy · 07-11-2003, 06:50 AM

Thanks sunroof. I don't smell any fumes, so I should be OK. I do have a kink in one of my lines to the charcoal canister that I need to fix.

I do have a cool collar but haven't heard of the Heat Sheet. Yeah I can see you would need those in GA. Virginia Beach can get pretty stinkin' hot as well, but my 73.5T is only out once or twice a week, and mainly on shorter trips.
Chris
73.5T