Engine Stalls, Engine stalls and dies out when I begin to release clutch Options

[mimatti]

Hello to all the 914 owners,

I am new to this forum and it looks like a great place to be regarding 914's. A little background about my 914 before I ask my question. It's a 1972 1.7Liter, that had it's two carburetor system replaced, in 2011, with a brand new single Webber Carb. I bought the car 4 years ago and unfortunately it's been sitting in my garage ever since due to various projects. I was able to drive it up the drive way and into my garage with no isuues, and she stayed there the entire four years. This weekend I decided to take it out and drive it a little. The idle was way too low, so I adjusted and got the idle to just under 1,000 rpm. The problem is when I try to start out in 1st gear, as I begin to slowly release the clutch, the engine's power dies to the point where the engines dies out. Even when I revved the engine to almost 3,000 rpm and then slowly released the clutch, about mid-way in the clutch's pedal travel, the engine's power is robbed, engine rpm goes down toward idle very quickly, and the engine dies out. I made sure that I was in 1st gear and not a higher gear, the problem persisted to the point where I couldn't even drive it back in my garage, I had to push it in.

Before I remove the carburetor, or and clutch work, does anyone have any idea of what the problem might be, or at least limit the possibilities to a system, i.e. fuel, air, carb, clutch, etc... I appreciate any help in this matter because I now finally have the time for this Porsche and want to begin enjoying it.

Regards,

mimatti

[zambezi]

Do you still have the dual carburetors?

[bandjoey]

Sounds fuel related. Pump filter bad gas carb rebuild. All need to be checked.
If you can dump the single carb.


OR. Locked brakes calipers. (IMG:style_emoticons/default/idea.gif)

[zambezi]

OR. Locked brakes calipers. (IMG:style_emoticons/default/idea.gif)

Doubt that is his problem, he pushed it back in the garage.

[last337]

Check fuel lines to fuel tank. Have you taken a look inside of the fuel tank for trash? I learned the hard way and chased my tail for weeks before pullifn the tank and cleaning it properly.

[mimatti]

Thanks for all the replies, unfortunately the previous owner threw out the dual carbs (IMG:style_emoticons/default/mad.gif) I wish he would have kept them, but the only carb on the car now is that single webber.

I haven't done any tracking on it yet since I just discovered the problem and I wanted to get 914 experts like you folks to chime in. Should I begin by checking to see if the jets in the carb are producing the shot of fuel needed for acceleration before emtying the fuel tank or start disconnecting fuel lines?

I told this problem to a friend who works on cars as a hobby, no Porsche's however, and he suggested that the clutch might be slipping, could that be true?

[914Mels]

If your clutch is slipping, it wouldn't make your engine die out, your engine would rev and the car wouldn't move like it should. Really sounds like a clogged up fuel system or a really plugged up air filter.

[mimatti]

That's exactly what I nned to know, is to narrow this issue down to a system or sub-system of the car, rather than just start pulling and replacing things on the car. I even removed the air filter and it still did the same thing, so I'm going to start chasing the fuel issue, as to why the engine is not getting the amount of fuel needed when there's a load on it.

[markb]

With a single carb, your fuel mixture will never be correct, so find a happy medium. The tubes are just too long for the fuel to move thru to be able to keep a good air/fuel ratio. If it has a cam for carbs, plan on going back to duals. If it has an FI cam, start collecting FI parts to do the switchover.

[mimatti]

Thanks for that, I'll have to contact the previous owner to see if he put in a cam for carb or FI cam. Yesterday I pulled off the fuel line going directly into the carburetor, I put the fuel line in tupperware to catch the fuel and filmed the pressure of the fuel coming out of the line. I tried attaching the 15 seconds video on here but kept getting an error trying to attach it on here. Anyway, I cranked the motor and then watched the video and it seems the pressure coming out of the fuel line was very good, not trickling, but actually being pumped out at a pretty good pressure. I also took a picture of the fuel captured in the tupperware and attached that picture with this reply. Seems brown to me.

This is what I have deduced so far and please guys let me know what your take is. The pressure going into the carburetor seems to be very good, so somewhere within the carburetor the pressure is not what it needs to be, so perhaps the jets need cleaning or maybe a diaphragm issue since the car sat four years without being driven. So needless to say, the carburetor is coming off and taking it in to get checked out, cleaned, replace any enternal part that needs replacement, and maybe even bench tested. I also realize the fuel is old and I need to completely drain all the fuel within the system and put in an entire tank full of new fuel and run that through.

What do you guys think of the diagnosis so far? Thanks

[DRPHIL914]

i'm not a carb guy so i others can chime in , but #1 drop the tank, and clean it and replace the fuel filter and the sock filter that is in the tank.
#2 if the fuel was that dirty i'm guessing that the carb jets themselves are not letting enough fuel thru- i went thru this with my BMW motorcycle and my Austin Healey that had dual carbs;
#3- even on my 75 that has original FI, If my timing is off the idle can be too slow and car will die, so you need to also be reverifying timing, check the valves as well. then you can set it statically then if you get it running well enough and warmed up set the timing, unless the engine was rebuild it probably still has the original cam in it and you can go back to original FI, that would give you your best performance and economy. Check the classifieds or post and WTB add , and convert it back.

Good luck ,

Phil

[mimatti]

Thanks so much for all the replies, I now have a better idea of where to concentrate my efforts :-)