BigAl1

During my MS3X setup process, I've been cranking the engine to calibrate sensors. Last night during a 10sec cranking, about 5 sec into it, there was a change in the noise from the engine - rattling sound, with faint tones from the flywheel in the background. It might be the same time my oil pressure gauge pegged at 5? It happened again the next time I cranked - same pattern. At first I thought it was the starter making rough noise, but my worries got to me later and wondering if this was lifter/valve noise as oil pressure came up? That got me even more worried - what if I have the cams 180deg off? My only assurance that I installed the timing belt correctly 3 years ago is my details oriented thinking back then.
I can put the #1 cylinder at TDC (no plugs installed), but how do I know the valves are closed on #1 at this time? Put a plug in #1 and see if the compression stroke happens as the cam gear approaches the mark on the housing? This is a 1980 4.7L Euro S motor, with Castrox GTX 20-50 oil.

Ducman82

are you spinning it with the plugs out? spins faster and i got some good data logs on the trigger pulses that way.

i always worries about oil pressure with all that "dry" cranking. i ended up taking the timing belt off and spinning the oil pump with a drill and it worked like a champ. are the oil pressure sender wires on the right posts? i know that can cause the gauge to be dumb.

without firing the engine you will get some change in pitch and engine load when the pump starts pulling and pressurizing the oil.....

BigAl1

Yep, plugs out. I have to check the oil pressure sender connections, but supposedly it is just a variable resistor, so should not matter connection order. I'm going to try a pressure tester tonight - to verify I have both valves closed at #1 TDC. The engine speed would change very slightly when the extra noise started - hopefully it is just the oil pump pressuring the system.

Ducman82

Stock sender has two wires. One for warning light and another for the gauge. I know when switched the oil pressure always reads max... Basically on/off

BigAl1

Thanks Jake - that sounds like my gauge problem - will look at that next chance I'm at the car. I think my wires were trashed when I got it, and had to rewire that stuff anyway, so easy for me to have them backwards.

BigAl1

All is well on the car - no rattling noise anymore. It could have been my lifters pumping up?