I have a inline 200 engine. The block is a 1966. The head is a large log 1969. I have installed a water temp sencer for the 69 head. The them gauge on my dash reports close to max line in a very short time and stays there. The cluser is a 65 setup. Now when I install a Spencer for a 65/66 block. Temp stays in mid range. The engine shows no sign of over heating. All new pump and rad. So what am I asking. Does anyone know if the ohm on a 65/66 censer is different from a 69 censer. Fyi. The 65 is a lot small in o.d. so I had to adapt it to fit
All Small Six Temp sensor
- Thread starter ScottGibs
- Start date
This relates to all small sixes
Hi ScottGibs, and welcome to the Ford Six Forum! Yes the Ohm reading of the senders can be much different and you for sure will need to use the correct 1965 Temp Sender Unit or one that matches those readings. You could adapt it into the 1969 Big Log Head with a pipe thread Bushing adapter so it work's with those 1965's stock Dash Gauge Cluster, as they will be the right Ohm reading that you will need. When swapping all these different year of engine parts together and by all means you do have a very good combo of engine parts for much better performance using a 1969 up Large Log Head on any of the 1963 1/2 to 1968 200 Six Short Block's. However its important that the sender units for the Water Temp and Oil Pressure or for any of the Ford OEM Dash Gauges will need to match their required Ohm reading's and or be for the year Model of the Car that they were used in, in this case it has nothing to do with all those different years of engine parts. Good luck
Looking at Rockauto, both the 69 and 66 200 engines take the same sensor (Standard Motor Products TS24) for cars with the temperature gauge (this assumes the original equipment gauge, not an aftermarket gauge).
There is a different sender that's needed for the 200 engines produced before 9/65. It's possible that some of those engines made it into the 66 model year (or that someone swapped a 65 head onto the 66 block).
It is also possible that one of your senders was for the dash with the temperature light, that it was an aftermarket sender with the wrong resistance range for factory gauges, or that it was a bad sender. Lastly, I've found through experience that if the part of the sensor that's supposed to be in the water is too short, it will only read the block temperature, and the guage will tend to go to the hot side and stay there rather than indicate the water temperature.
There is a different sender that's needed for the 200 engines produced before 9/65. It's possible that some of those engines made it into the 66 model year (or that someone swapped a 65 head onto the 66 block).
It is also possible that one of your senders was for the dash with the temperature light, that it was an aftermarket sender with the wrong resistance range for factory gauges, or that it was a bad sender. Lastly, I've found through experience that if the part of the sensor that's supposed to be in the water is too short, it will only read the block temperature, and the guage will tend to go to the hot side and stay there rather than indicate the water temperature.
"...resistance range for factory gauges..."
back to my issue w/lill automotive ele knowledge.
How to measure resistance in ordered temp sender and dash gauge?
I may have oem ('1970) gauge around ('long pointed') but have a '69 (my motor) 'chunky style' in my hand. Temp send's in the 250's a tight fit w/head against the fire wall. Wanna keep it there if possible.
Need to follow the thread's main point "They match (gauge/sender)" and different pipe thread Dia/Count - designs... we gota box of brass but my problem is what multi meter/how to use... Are all '70 bronk's dash gauges (1 i6, 1 bent8) gunna have the same resistance? Buy a model for the '70? 1 probe on tip, one on body threads? spin dial to ohms ("upside dwn U"). Assume that's correct for dash gauge/follow up accordingly?
Not off topic, Scott, HIH~
back to my issue w/lill automotive ele knowledge.
How to measure resistance in ordered temp sender and dash gauge?
I may have oem ('1970) gauge around ('long pointed') but have a '69 (my motor) 'chunky style' in my hand. Temp send's in the 250's a tight fit w/head against the fire wall. Wanna keep it there if possible.
Need to follow the thread's main point "They match (gauge/sender)" and different pipe thread Dia/Count - designs... we gota box of brass but my problem is what multi meter/how to use... Are all '70 bronk's dash gauges (1 i6, 1 bent8) gunna have the same resistance? Buy a model for the '70? 1 probe on tip, one on body threads? spin dial to ohms ("upside dwn U"). Assume that's correct for dash gauge/follow up accordingly?
Not off topic, Scott, HIH~
Note that it was hard to see it above, but he stated that he has a 1965 Dash Gauge Cluster (Mustang's and some of the 1965 Falcon's shared this Gauge Cluster), but nothing else about the model of the car that the 1966 200 short block with a large Log Head was in. I believe he also said he was working on a 1965 Mustang if I remember right in some of his other Posts.
yeah, my 1st run-in years ago w/it was a gas tank sending unit & the dash gauge. I was able to see what each needed (from paper work) and match ohms. Here? not so easy to find the dash's need. I guess U can run some juice thru it and tell by readings on a multi.m. (watch the 2 needles).
I did notice that he had a 65 cluster. I had to find one listed on eBay to see whether it had the gauge or the light (they have the gauge).
Those clusters used the same gauge mechanism (heater that bends a bi-metal strip) and CVU that the earlier and later models use. There are charts floating around in other forums that provide sender resistance versus gauge readings. I'm attaching one which, even though it says it's for "temperature", also applies to the fuel and oil senders/gauges insofar as sender resistance and deflection of the pointer on the gauge.
Insofar as checking senders, oil pressure senders can be checked with a regulated, gauged line from an air compressor fitted to the sender thread. Temperature senders can be be checked with a pot of water on a stove, an accurate thermometer and an ohm meter. I have checked the fuel sender by hooking it up to the car and moving the arm to see the gauge readings at different positions.
A quick way to check a factory temperature, oil pressure, or fuel gauge is to connect a known "good" sender to it. To the best of my knowledge all of those gauges have the same mechanism inside with different faces.
Those clusters used the same gauge mechanism (heater that bends a bi-metal strip) and CVU that the earlier and later models use. There are charts floating around in other forums that provide sender resistance versus gauge readings. I'm attaching one which, even though it says it's for "temperature", also applies to the fuel and oil senders/gauges insofar as sender resistance and deflection of the pointer on the gauge.
Insofar as checking senders, oil pressure senders can be checked with a regulated, gauged line from an air compressor fitted to the sender thread. Temperature senders can be be checked with a pot of water on a stove, an accurate thermometer and an ohm meter. I have checked the fuel sender by hooking it up to the car and moving the arm to see the gauge readings at different positions.
A quick way to check a factory temperature, oil pressure, or fuel gauge is to connect a known "good" sender to it. To the best of my knowledge all of those gauges have the same mechanism inside with different faces.
"... clusters used the same gauge mechanism... and CVU that the earlier and later models use...."
I thought it was just said that may not B true. ok, gud then.
I was thinkin 7 - 10 ohms range for the gas sender/gauge.
The H2O temp is alot more in ur chart &/or I am way
off on gas. Thanx John, this could help me (if anything
can) LOL. (Ex: CVU means CardioVascular Unit in my
wrk experience). If needed the bush ( ID/OD not thread
pitch or count) might B hard to find. I have seen them
in near ranges tho (used w/air, water'n fluids)..
Temp'n pressure I wrk with, ohms I will need to grow.
Just 1 experience in past (called 'lucky'? 'unlucky'?).
I thought it was just said that may not B true. ok, gud then.
I was thinkin 7 - 10 ohms range for the gas sender/gauge.
The H2O temp is alot more in ur chart &/or I am way
off on gas. Thanx John, this could help me (if anything
can) LOL. (Ex: CVU means CardioVascular Unit in my
wrk experience). If needed the bush ( ID/OD not thread
pitch or count) might B hard to find. I have seen them
in near ranges tho (used w/air, water'n fluids)..
Temp'n pressure I wrk with, ohms I will need to grow.
Just 1 experience in past (called 'lucky'? 'unlucky'?).
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The "normal" resistance range for senders that interface with factory gauges in the old Fords (of the vintage we normally deal with here) is 10-75 (or 78) Ohms. 10 Ohms is "full", "Hot" or "High" and 75 Ohms is "E", "C" or "L" (for fuel, temp and oil pressure, respectively).
If you're not sure about the sender resistance needed, it's easy to look on RockAuto to cross reference part numbers. I know for certain that the 65-66 Mustangs senders have to have the resistance range I quoted above for their factory gauges (aftermarket gauges are a whole other rabbit hole). So if the same part number is used in the same engine for whatever year you're trying to work with as is used in the same engine for a 66 vehicle, you know what the gauge requires insofar as sender characteristics.
Did that make any sense at all?
If you're not sure about the sender resistance needed, it's easy to look on RockAuto to cross reference part numbers. I know for certain that the 65-66 Mustangs senders have to have the resistance range I quoted above for their factory gauges (aftermarket gauges are a whole other rabbit hole). So if the same part number is used in the same engine for whatever year you're trying to work with as is used in the same engine for a 66 vehicle, you know what the gauge requires insofar as sender characteristics.
Did that make any sense at all?
you'll see a '70 bronk to the left. So yeah,
some sense. Kuwell they all wrk the same way.
I have so lill time to put into this project (10 min - 1/2 hr)
each occasion I do it's difficult to geta rhythum. I have a box
w/parts - a needle type sender from the old motor and a 'chuncky'
new. I may hafta bush out the 170 for the 250. Not sure... I know when
the boss re-wired the engine bay (brought ona pmgr starter, 3G alt) I got no
needle response on the H2O temp even w/ 10 min run. 8- (
some sense. Kuwell they all wrk the same way.
I have so lill time to put into this project (10 min - 1/2 hr)
each occasion I do it's difficult to geta rhythum. I have a box
w/parts - a needle type sender from the old motor and a 'chuncky'
new. I may hafta bush out the 170 for the 250. Not sure... I know when
the boss re-wired the engine bay (brought ona pmgr starter, 3G alt) I got no
needle response on the H2O temp even w/ 10 min run. 8- (
