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Posted by: STP May 31 2006, 06:48 PM

So, My 914 has been sitting at my grandmother's house for the last 2 months and after finally being able to work on it again I've run into a few problems.

Firstly, none of my gauges are working. Not the tach, not the fuel gauge, nothing.

Second and more importantly, I was checking and adjusting the timing on the dizzy according to the PP article, and the engine started making this knocking noise. I'm not sure what it is. At first I thought it was preignition, Seeing as I advanced the timing, but it sounded mechanical, like lifters maybe but really loud. Then I thought because it hadn't been started in a while that maybe I should have primed the oil pump. But, like I say, I have no idea so far.

I did a compression test on it before I put it away and one of the cylinders was about 40psi lower than the others.

So my questions are:

What could the gauge problem be? I dont even know where to start so even that would be helpful.

What's the most likely answer to the knocking problem?

What do I do about the low compression? I thought 40psi was kinda high. Will I need to get a valve job? Could this be related to any of the other problems I'm having?

Compression:
140
120
120
100
I have a 73 2.0 with Webers (40s) if this helps.

Thanks for all your help, Sean

Posted by: lapuwali May 31 2006, 06:56 PM

On the gauges, it's most likely a fuse. I can't remember which fuse, but look for the one that powers the red/white wire, which powers the gauges. Even if all the fuses LOOK OK, try wiggling and rotating them in their holders.

I can't answer you knocking question. Set the timing to factory specs, and if it knocks at idle, it's not likely a timing problem, but something else. Noises are very hard to diagnose remotely.

Which cylinder was low, and what were all the numbers? What's the color of the plug on the low cylinder? Adjusted your valves recently?

Posted by: SirAndy May 31 2006, 06:59 PM

for the gauges, check the fuses first ...

for the knock, could be a dropped valve seat ...

Andy

Posted by: STP May 31 2006, 07:07 PM

Would a dropped valve seat be intermittant though? I can still start it and run it.

Posted by: So.Cal.914 May 31 2006, 07:20 PM

No it would not, after reading your post it started after you advanced your timing.

Correct? I would say reset your timing to factory specs and see if it goes away.

What andy said about the fuses. Check plug color, post a pic of plug.

Posted by: SirAndy May 31 2006, 07:21 PM

no. the noise would be LOUD and always there ...

one time i drove 50+ miles (T1) after a exhaust valve/seat had left the motor through the exhaust.

another time i drove (T1 again) for 50+ miles on the german autobahn after a rod-bearing decided to explode on me.

smoked like a smoke-stack, but ran ...
Andy

Posted by: bd1308 May 31 2006, 08:16 PM

Damn andy, you're lucky. My valve decided to go through the piston and lock up the engine. LOL

b

Posted by: STP May 31 2006, 10:22 PM

ok, I'll mess with the timing again tommorow and see if I cant get the gauges working.

Does it sound like preignition to anybody? I dont know what else it could be, if its not something mechanical.

thanks for all your help.

Posted by: So.Cal.914 May 31 2006, 10:34 PM

Yes it does sound like preignition, air cooled engines for what ever reason seem

to amplify the knocks more than most others.

Posted by: STP Jun 1 2006, 06:13 PM

Well, I started it up today after retarding the dizzy a bit and it's still making the noise and its no longer intermittant.

One of the fuses was loose, the gauges are working fine now.