CIS start up after a long-ish lay up - advice please!!
 

Hi All,

I've had a search and a good read through previous postings regarding CIS and the dangers of letting it sit with fuel in, well, you guessed it, I'm the proud owner of a car thats sat for a while (exact time unknown but likely 18 months - 2 years).

I've drained the fuel out of the tank, but not yet put fresh fuel in - my question is should I put some kind of fuel additive in there that may help with removing fuel varnish from injectors & lines etc. and can someone recommend one to use (pref. thats available in the UK).

Any other pointers? I will be replacing the fuel lines before start up by the way.

Thanks

Car is a 74 911 fitted with a later 3.0 CIS motor btw

I'm assuming you've pulled the tank drain plug or bung (labeled Bezin) and checked the outlet filter screen mounted there on. Also change the fuel filter and put in new oil and oil filter. I assume you know there are many fuel lines on a 1974/1978 (year of the 3.0?) CIS fuel system including two in the tunnel. Changing them all is not a trivial matter but well advised at least the fabric covered rubber hose sections. I have no knowledge of UK fuel additives/fuel injection cleaners; in the US, Chevron Techron is commonly used in Porsche 911 fuel systems.

change the oil, change the fuel, charge the battery, and see if she starts up. dont go messing with the fuel lines, it is a bird's nest, that is running thru tight spaces. it will be fine. you could go crazy and give her a minor tune first, plugs, rotor, cap. after she starts and floods your neighborhood with smoke, refrain from posting the "my car is smoking crazy!" thread. that will be normal. do it at night and kill some bugs, it will clear up.

before you drive, inspect and bleed brakes. have fun and post a picture.
heck while i am at it, let me help you avoid a few other thread starters:

check you oil level with the car idling and fully warmed up, dont drop your dipstick into the filler neck, get a really big oil pan, because the oil comes out fast and there is lots of it. we all like 20/50 wt oil. anal freaks like kendall, the rest likes castrol GTX, leftie loosey righty tighty, and yes the smile really will never ever go away, and no your significant other will not really be interested when you run parts into the home and yell, "honey, check this out!"......

Woo -hoo!!!

Thanks guys for all your advice, fired her up finally this morning.

Smoke you say? Neigbours thought I was doing an insurance job and were at the ready with an extinguisher!!!!

Took her gingerly around the block - my first drive in ANY 911, and any Porsche barring my brothers 924 and I am in love!

Heres to driving Porsches - I'm absolutely hooked!

Thanks all...

Jamie

Replace all vacuum lines and fuel hoses while you're in there, you'll be glad you did!

Cliff, you crack me up.

Jamie,

Welcome to the Forum.

A ’74 with a 3.0 should be a great car. Show us some images. Where are you located? There may be other Pelicans in your area who can help.

Sounds like you have the engine running as a mosquito eradication project. Please be very careful to not damage anything. Keep the rpm low and don’t let it get warm until you are sure of the condition of the engine. You don’t want a broken ring trashing anything. The above advice is right on.

Now that it is running, do a cranking compression test and a cylinder leak test. That should allow you to make informed decisions about more driving.

You may want to remove the muffler and have it cleaned at a radiator shop to remove the oil. Otherwise you may not be able to tell if/when it quits passing oil.


There a couple of other issues you should attend to.
First, while you are under the 911, confirm it has sufficient transmission lubricant. A transmission oil change probably is a good idea. Check the CV boots and the CV bolts for tight while you are there.

Pay very close attention to any level drop in the brake fluid reservoir. 911s this age can have master cylinder failure, particularly when left to set.

Have you checked the tyre pressure and wheel nut torque?

Using the Search function there is a wealth of information available.

Feel free to ask questions here. There is no such thing as a dumb question. We have all been there.

Best,
Grady

Thanks for the information chaps, all duly noted and I will be working my way through the list - I've already replaced shocks & tyres and gone through the brakes, transmission & engine are now in for a pampering.

Thanks again, I'm sure I'll be back on before long pestering for more info!

Cheers
Jamie

ps will post pics as soon as I have some

A product call Redline is a good one. Not sure where you are. They have one for fuel (gas) and one for diesel.