GT40 Engine Questions

Only broke 2, both on the driver side.  Installed with stainless bolts and lots of anti-seize.

Exhaust manifold is almost completely closed at water outlet.  Hose is collapsed into manifold.

You can clean up those risers and manifolds pretty quick if you get a rubbermade type of container large enough to hold one. Being careful you can soak them in muratic acid- it will clean the insides of that crud. Keep an eye on them as you do it you don't want them in any longer than necessary. 

Last time out, Tue 3 Nov, 65 degrees air temp, the problem is gone.  It may have something to do with the engine running hot, or the intake air temp sensor.

Soak those old bolts in a 50/50 mix of ATF and acetone.  Pour some on and let it soak in, overnight or longer if you have time.  Re apply a couple times if possible.  ATF = automatic transmission fluid.

Final update on this engine.  When replacing the impeller I decided to replace the thermostat too, only there wasn't a thermostat there.  The PO or the POO evidently had cooling problems and instead of replacing the impeller the just removed the thermostat.  With the new thermostat and impeller the engine stays rock solid at 160 degrees on the gauge.  

I ran the pumps with the key on and the ground wire at the test connector.   Ran them several times, sometimes fuel pressure would hold.  Never got to test full throttle fuel pressure, engine got hot at dock.  Engine runs strong but I think it has more in it.  

If you have a mechanics stethoscope I would listen to the injectors while the engine is running.  Each injector should be making a very specific snap snap sound as the injector opens and closes while running.  If one is quiet, and your engine still runs strong, one is not closing.  Could be more than one.   Another way to test the pressure regulator is to block off the return line.  Your pressure should go much higher and stay there because it has no place to go.   Be careful how you block it off because the system may see 80 PSI or more blocked and you could create a high pressure gasoline spray gun doing this if your block off blows out.

MrMcD wrote: First, pressure does not evaporate when the key is shut off.  There is a spec, it will say something like pressure should hold for five minutes and slowly decline over the next 30 minutes.  If you are losing pressure instantly you have a large leak.  Either the pressure regulator is stuck open or your injectors are not closing.  Black smoke on a restart points to injectors. Mark

Okay-

Spout

When checking timing on a GT-40, don't forget about that little puck, thing, I can't remember what it's called, but you have to unplug it to get back to base timing.

I can check the timing.  Was a powered equipment mechanic in the Air Force.

What he said .  Heads were already rebuilt so they were clean,valve covers rockers,push rods, block sludge wise were clean. But the oil left in the pan was nasty. Bearings worn but not scored or damaged. Crank only required a polish. Injectors were gone but new in the box Motorsport ones were included.LP pump making noise. I have new pumps and several ECM's  When I get it running I'll keep an eye on everything and test the knock sensor. Something made #8 go bad and it's failure spread debris through several other cylinders

MrMcD wrote: Gary what caused your engine failure?