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| | | Forums66 Topics128,100 Posts1,056,513 Members48,448 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
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For helping keep this great
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | I have an older 305 Chev and want to put in an electrical water temperature gauge. The thermostat housing has a couple of holes with plugs in it and also beside the housing there is a plug which appears to be going into the water jacket on the intake with a wire attached. Sorry I am just going by memory now but will try to get a photo ASAP. | | | | | Joined: Feb 2004 Posts: 29,835 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,835 | Since small block V8 cylinder heads are interchangeable from side to side, the coolant port at the back of the head dead ends into a passageway in the intake manifold. By drilling and tapping the manifold for a pipe thread, a temp sensor can be installed back beside the distributor on the driver's side of the engine which will give a more accurate picture of actual coolant temp than one in the thermostat housing. We used that method to monitor coolant temp on the race engines for many years. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | Thanks Jerry. But the talent to achieve that is way beyond me. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | It is not that hard, take it slow, gather proper tools, take pictures, ask here! We all had to start somewhere!
Ed
Last edited by EdPruss; 04/03/2023 11:36 PM.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Jul 2000 Posts: 2,196 Insomniac | | Insomniac Joined: Jul 2000 Posts: 2,196 | I replaced a temperature idiot light with a gauge on a 350. I simply removed the idiot light sensor and installed the gauge sensor in it's place The threads were the same. I even used the same wire back to the instrument panel.
Gord 🇨🇦 ---- 1954 1/2 ton 235 4 speed | | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | Where was the sensor located? | | | | | Joined: Feb 2016 Posts: 1,990 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,990 | As HRL said, the small blocks heads are interchangeable side to side. Each head has at least one threaded port on the exhaust side of the head, typically the left head has the temperature sending unit but there is no reason that the right head could also be used for another sending unit. Chevrolet used a green single wire for the temp sender on the left, front.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Apr 2005 Posts: 2,832 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,832 | Here is a photo of what Jerry (HRL) was describing. I do it on V8 conversions as it lets one use the factory sensor and capillary tube rather than the pricey after market one long enough to reach the port on the head or T-stat housing. A grinder, drill and tap are the only tools needed. Flat spot ground on left rear of intake and then drilled and tapped for temp bulb brass fitting: [img]https://i.postimg.cc/ftLtprqY/S10-054.jpg[/img]
Evan
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