fired up the new motor finally () and now just doing a temp install of gauges (cab still off chassis) to verify everything before going back together.

picked up speedway's (omega) 4-in-1 gaugeset for '52 F1. had already purchased new oil pressure and coolant temp sending units. wired the gauge up, but both oil pressure and temp peg immediately upon starting. pulled sending units and removed teflon tape "just in case", but same behavior with paste. was told i needed to use the sending units which came with gauge (wrong size for my '95 5.8), so picked up adapters to do so. still the same problem with those sending units.

verified good (50psi) pressure with a mechanical oil gauge. continuity good on circuit from oil sender back to gauge.

any thoughts on how to proceed?

 

Wow, some guessing here. I used the ones that came with my gauges from New Vintage Usa... You should contact the seller to see what he can come up with... sorry

 

 

This may sound a bit obvious, did you check the ground? I know some gauges will peg immediately if there is a grounding issue. Also, is the cluster installed in the dash? (Housing get grounded through the dash.) Good luck!

 

hmmm...
no, not installed in dash (cab isn't on chassis) -- just checking out everything in advance, so gauge in box. however, there is a 'ground' wire from the gauge which is grounded.

voltmeter seems to be fine, but oil and temp peg out.

 

I tried! I've never used the 4-in-1 style. I'm currently having a problem with my fuel gauge. When I take the ground off, it pegs to full (if I remember correctly). Was thinking if your gauges were pegging, it may have to do with the ground too. My oil and temperature are mechanical gauges so can't help you troubleshoot there.
Is the engine grounded to anything? (Not sure if the engine to cab or engine to frame ground would impact this issue)