temp gauge question

[Streetgliderx]

Ok when i bought my GMGOODWRENCH motor it had an water sensor port in the head LARGER than the one i pulled from my old motor... so i bought one that was for an older chevy so the thread size would match but ever since my temp guage shows right to that notch between 210 and red.... now i took a hand held temp gun and checked eveything and idling on a hot day it only runs 178* on the freez plugs all over the engine. the rad itself runs about 150* so i aint overheating but the guage read fine before the swap so it has to be that temp sensor but i was wondering what do do to fix it i hate to bushing the threads to hold the later model temp sensor... also i am running a 180 thermostat

thanks

 

[Streetgliderx]

ttt

 

[USSkoval]

When I swapped heads on my '86 350 TPI, I used a temp sender for a '78 Chevy van w/ 350. It reads correctly and had the right connector to boot. I also remember that autozone did not have a listing, but NAPA did.

 

[Streetgliderx]

cool i'll look into it

 

[Justin Fleming]

Any more feed back on this... I am having the same problem..... sens I did the swap from a 305 to a 350

 

[ryoken]

just put a pipe bushing in it and run the old sender...

 

[GMC Truck]

Mine is the same way. Gauge shows almost in the red but the scan tool hooked up to monitor the temp being used by the fuel injection shows 187 degrees. Has to be a problem with the aftermarket senders?

 

[4X4HIGH]

You can use either sensor and they will read the same UNLESS you installed one for a light when you have a gauge or vice versa.

 

[Laguna37]

just put a pipe bushing in it and run the old sender...

x2

I swapped from a 305 with a temp gauge to a 350 and the sending unit was a different size and my temp gauge showed the truck was always over heating. Bought a 3/8" female to 1/2" male NPT fitting and put the original sending unit in, works perfect on my gauge again.