Type 4 cyl 1 and 3 no power...

jeff k · Post by **jeff k** » Tue Apr 24, 2001 3:30 pm

Hello. I have a Porsche 914 type 4 in my Porsche 912 while I am rebuiding it's engine. The type 4 is a 1.7 with two solex pdsit/3 (Bus)carbs currently on. There is no crossover pipe because it is like two "right" bus carbs. The carbs are N.O.S. so I do not think it is fuel related. New elec pump too. Spark is good all around and the wires are new and in correct order. I am wondering if you can help me troubleshoot a problem? I have rigged the throttle cable up to satisfaction but while checking the motor out I notice that cylynders 1 and 3 do not "rev up" when the other spark wires are pulled. 2 and 4 rev when wires go back on. So each cyl is firing but something is wrong. I can see the red timing flywheel mark (like a slot) but I also saw a black painted triangle that corosponds with the triangular timing "sight" in the case. Does this ring any bells? The car seems sluggish (like running on two cylinders would) and yet there are new plugs all around. I have a Bosch .009 distributer in there now and I think it is timed correctly but anyway there it is... Could the heads have become loose? Obvioulsy if so, I will tighten them. Since this car had old gas, maybe a couple of valves are sticking? If so, is there a quick fix like pouring trans fluid into carbs while running it? I am wondering if I could have done something silly? I know the point gap may be too big or small. Could this be causing power loss? I adjusted the valves "out" with lots of play now until I got it running. I will adjust them properly soon. Could too loose valves cause this? Am I right to assume that this should not be the problem provided the rings and valves are working ok? Compression seemed equal on all 4 cyls when I had the engine out... I have an extra 009, so I will try that too. Also, it seemed like the guy that had it before had the timing 180 degrees out at the dist. drive gear. I will change that, but could that have caused this symptom? Well, any suggestions appreciated. e-mail me direct is ok... [email protected]
in Phoenix, AZ

Joseph · Post by **Joseph** » Wed Apr 25, 2001 7:02 am

Jeff,
Find yourself a left carb and balance tube
with the air speed adjustment in the tube
as well.
Engine 101:
In the course of making an engine
run you need (1)compression, (did you do a
compression test?) (2)spark, (must happen at
the right time on all the cylinders) and (3)
fuel. (Fuel of acceptable quality must be
available to each cylinder.)
Run down each of the three requirements and
you will locate the problem.
Joe
Oregon Performance Products http://www.spiretech.com/~opshroud

stevestromberg · Post by **stevestromberg** » Wed Apr 25, 2001 7:27 am

I have a set of 34 weber 1bbl carbs and manifolds for type4. $150.00 Steve

Michael Ghia · Post by **Michael Ghia** » Wed Apr 25, 2001 8:37 am

Check that the vavles on 1 and 3 are opening fully. It could be that your cam has gone flat on either the Inlet or Exhaust as 1 and 3 use the same lobes.
Check compression. You have plugged up the holes in the manifolds for the balance pipe haven't you?
Mike Ghia

------------------
Modification is a form of Art.

jeff k · Post by **jeff k** » Wed Apr 25, 2001 11:17 am

OK, Got it running stronger now. Had a new 009 around. found cly 1 was tight. Will do the other side soon. Looks promising. Not buying Webers now... I am not looking for speed/power just regularly advertised speed/power.