Question re: Fuel Injectors

[Kryptonite]

I just recently purchased a 1973.5 911 T and have removed the engine to repair rust damage to rear shelf. While the engine is out, I am planning to repair oil leaks and have noticed the fuel injectors are somewhat loose in their housing. Is this a problem?
When do they need to be replaced?

Also, does anyone have any suggestions as to what else I should be looking at doing while the engine is out?

Thanks in advance.

Manfred

[vash]

you need to replace them when the spray is pathetic. but you cannot test them now. i would yank one, and take a look at the o-ring. those are cheap and fairly easy, especially since you have the motor out.

btw, this question was probably better suited for the 911 tech forum.

[Jim Sims]

The seals on the CIS injectors for the 1973.5T cars are different from later years (as are the injectors). The seals shown on the Pelican parts website catalog are not correct. The correct seals are Porsche Part No.: 911.110.922.00 and are $8.93 each (you need six). If the seals on your injectors are original they are likely hard and not sealing well. To remove the injectors you will need to make a tool (can be made from a flat prybar called a "Superbar" with a rat tail file or a small grinding stone mounted in a die grinder) to pry them out; do not pull them out by the fuel lines. You do not state the condition or history of your engine or the location of the oil leaks. There are many things one can do while the engine is out. It depends on how far you want to go and how much money you have to spend. Easy things to do and relatively inexpensive are replace the engine mounted oil thermostat o-ring, the breather cover gasket, remove the engine mounted oil cooler, clean and remount with new seals, check for and repair any damage to the engine electrical wiring harness, replace all the braided vacuum/fuel lines on the engine and replace the sump seals and clean the pickup screen (there are two seals there - one above and one below the screen holder flange). Also clean and lubricate throttle linkage on the top of the engine. More expensive and more difficult but probably very important (to avoid a future fire) if they are original is to replace the rubber sections of the fuel lines running to and from the tunnel, the fuel pump and between the accumulator and fuel filter. Also, if not already installed you should install a pressure relief valve (pop off valve) in the air box. This is an easy time to do a valve adjustment, replace the valve cover gaskets (a common source of oil leaks) and check for loose cylinder stud nuts. One can also remove the induction system and fiberglass air shroud or guide from the top of the engine and clean the cooling fins on the cylinders and heads. This requires replacing the seals between the induction runners and the heads; this is also a good time to inspect for cracks or splits in the short rubber sleeves or boots which connect the induction runners to the air box. There's more: install pressure feed chain tensioners; trim the sheet metal baffles between the cylinders for improved air cooling, remove the oil tank from the right rear fender and clean dirt, oil and debris off it, replace breather hoses to oil tank, and so on. Depends on the time and treasure you have. Cheers, Jim

[Kryptonite]

Thanks for the info!

Unfixed: I appreciate the heads up on which forum to post to being that it was my first post.

Jim: Your info was very helpful and much appreciated. Do you know if there is an easy way to stop crud from dropping into the engine while cleaning? Should I go through the trouble of making plates to close intake and exhaust openings? As to the history of the engine, that is an unclear area - unsure. Money is no object (just don't tell my wife!) Seriously though, I hope not to spend buckets but as I get into this project it seems inevitable.

Thanks again.

Manfred

[Jim Sims]

On the 1973.5 T one can use rubber corks or rubber chair leg tips available in hardware stores in various sizes to seal the intake and exhaust ports to the heads. However, I do not recommend you remove the heater boxes (exhaust manifolds) unless absolutely necessary as there is a risk of breaking an exhaust stud(s) and then having to pull off a head(s) to have repairs/replacements done. If you do elect to remove the heater boxes then you need to obtain the use of an oxy-acetylene torch (other types of torches do not produce sufficient heat); heat the nuts on the studs one at a time until they are cherry red then loosen them while they are still hot. If you take off the induction manifold, before you remove it, account for every nut and washer from every stud to ensure that there is not something left behind that could fall into the engine. I have been through the experience of restoring a 1973.5T and have a copy of the illustrated factory parts catalog if you ever need a part number. I also have a few photographs that I can upload or send to you. Cheers, Jim

[Jim Sims]

73.5T engine without induction and CIS fuel system; note the white rubber chairleg tips plugging the intake ports; the injector ports are sealed with small cork plugs futher secured with masking tape. Cheers, Jim

[Kryptonite]

Thanks again Jim:

I would really appreciate any pictures you have of the engine and restored car.

My email address is : tech@kanteryachts.com

I will be away for the next week on vacation.

I have already removed the heat exchangers to repair a broken stud from previous owner. I plan to weld a nut to the top of the broken remaining stud to remove.

Your engine looks fantastic. Mine is a long way from that but I am looking forward to the restoration process.

Thanks
Manfred

[Jim Sims]

I have posted some images previously on the site; see:

Brad and his '73.5T

I will cut down some more images and e-mail them to you over the next week or so. Cheers, Jim