FYI FORD - MustangSteve's Ford Mustang Forum
The Internet's Most Knowledgeable Classic Mustang Information
IF YOU HAVE A QUESTION ABOUT CLASSIC FORD MUSTANGS, YOU HAVE COME TO THE RIGHT PLACE!
MustangSteve has over 30 years of Mustang experience, having owned 30 of them and restored several others. With the help of other Mustangers, this site is dedicated to helping anyone wanting to restore or modify their Mustang.... THERE ARE NO DUMB QUESTIONS!!!!!
Visit MustangSteve's web site to view some of my work and find details for:
FYIFORD Contributors' PICTURES - Power Brake Retrofit Kits for 65-66 Stangs - Classic Mustang FAQ's by MustangSteve - How to wire in a Duraspark Ignition - Mustang Ride Height Pictures and Descriptions - Steel Bushings to fit Granada Spindles to Mustang Tie Rods - Visit my EBAY store MustangSteve Performance - How to Install Granada Disc Brakes MustangSteve's Disc Brake Swap Page - FYIFORD Acronyms for guide to all the acronyms used on this page - FYIFORD Important information and upcoming events

You are not logged in. Would you like to login or register?

3/16/2019 2:08 PM  #26


Re: tapping thermostat housing

MS wrote:

Much easier to drill and tap a new hole in the intake manifold.  That will also send the proper temperature to the sensor rather than being downstream of the tstat.
Sawa comment about pipe thread taps not being any different than straight thread taps.  BE CAREFUL WITH THAT!  The tapered tap, if tapped too deep, will allow the male pipe thread to go in too deep, sometimes to the point of falling all the way through the tapped hole!  So, don't tap anymore than just barely enough threads to get the male part to seal.  And deeper and you risk an oversized hole that will never seal.
I drilled and tapped my intake manifold behind the distributor to install an extra sensor, using 1/8" pipe threads.

Good call. I should have been more clear.

Last edited by Raymond_B (3/16/2019 2:09 PM)

 

3/16/2019 3:10 PM  #27


Re: tapping thermostat housing

When taping with a pipe tap I always stop and trial fit to make sure I get the fitting, sensor, etc. the depth I want.  I learned this when taping the front of engine blocks for screw in plugs instead of welch plugs.  There's one in both Fords and Chevys that if you go too deep you block an intersecting passage and disaster ensues.  The fear of that taught me pipe tap discipline.  Its like cutting a board.  I can always cut it again if its too long, but I just can't cut it longer if its too short. 

 

3/16/2019 5:05 PM  #28


Re: tapping thermostat housing

My situation presented a similar problem. The EFI installation on my 302 required that I use the location usually reserved for the gauge sensor to be used for the EFI sensor. I had a thermostat housing with a tapped port, where I relocated my gauge sensor. During warm-up, the needle on the temp gauge will not move, but when the thermostat opens, the needle climbs very quickly to the operating temp. It's a good visual indication that the thermostat is working properly. I found that the temp gauge readings were virtually unaffected by the change.

Last edited by rhutt (3/17/2019 5:11 AM)


'66 GT Fastback, 302, Edelbrock top end, Sniper EFI, MSD, JBA Headers & Exhaust, T-5Z, Currie 3.55 Trac-Loc
 

3/16/2019 7:28 PM  #29


Re: tapping thermostat housing

How has the Sniper efi performed for you ?  have been looking at the SNiper and the Fitech but have just stuck with carbs to avoid potential headaches
 

     Thread Starter
 

3/16/2019 8:54 PM  #30


Re: tapping thermostat housing

Still in the tuning/learning stage, but the tune I have on it now is working out really well. There is more of a learning curve (and I don't mean the Sniper) than Holley would lead you to believe. Once you grasp the basics, you can throw a new tune on it in minutes to try different settings. Previous tune setups are saved so you can always revert back to the last (or best) one. I'm happy with the decision I made, but EFI would not be for everyone!


'66 GT Fastback, 302, Edelbrock top end, Sniper EFI, MSD, JBA Headers & Exhaust, T-5Z, Currie 3.55 Trac-Loc
 

3/16/2019 9:37 PM  #31


Re: tapping thermostat housing

I've thought about going to electric fans but the thing holding me back is the 'fan logic'. As long as the radiator is cooling properly the thermostat keeps the engine below its rated temp. This means that the best way to monitor the temp would be to have the sensor in the radiator itself. That way when the coolant in the radiator drops below the sensor rating, the fan(s) switch off. It should remain this way until the thermostat opens and exchanges block water for radiator water, when the temp rises above the sensor rating. The problem for me is putting a hole in a perfectly good radiator before it needs a rebuild.

Sensing off of the engine temperature would be a bit of a problem because you aren't sensing the actual state of the coolant in the radiator. Sensing at the water neck presents the same problem. Sensing it in the radiator tank would be the most accurate for fan control. When I tried an electric fan setup back in the late 80's the kit came with a temp probe/relay pack that you inserted in between the radiator fins to sense coolant temp in the radiator. It was adjustable and had a connector for the A/C (if equipped) for fan override. It never cooled well (but the fan controller worked OK) so I pulled it and went back to old school. I still have the controller and I'm thinking about giving it a try again now that there are much better electric fans available today.

But the best thing would be an in-tank sensor, IMO.

 

3/16/2019 10:11 PM  #32


Re: tapping thermostat housing

I recently replaced the T-stat housing on my 65 using one like that so I could retain both the idiot light and run a real temp gauge off the sender in the manifold.  If it's like the one I bought from O'Reiley's , the thread is not actually 3/8 NPT but is a straight thread 3/8" thread with the same TPI as a 3/8 NPT.  I ran a 3/8 NPT down in it in order to use the original thermostat.  Now my new gauge reads the temp normally and the idiot light sensor I put in the T-stat tells me when the thermostat opens.
 


Cheap, Fast, Good:  Pick Any Two
 

3/17/2019 6:43 AM  #33


Re: tapping thermostat housing

351MooseStang wrote:

I've thought about going to electric fans but the thing holding me back is the 'fan logic'. As long as the radiator is cooling properly the thermostat keeps the engine below its rated temp. This means that the best way to monitor the temp would be to have the sensor in the radiator itself. That way when the coolant in the radiator drops below the sensor rating, the fan(s) switch off. It should remain this way until the thermostat opens and exchanges block water for radiator water, when the temp rises above the sensor rating. The problem for me is putting a hole in a perfectly good radiator before it needs a rebuild.

Sensing off of the engine temperature would be a bit of a problem because you aren't sensing the actual state of the coolant in the radiator. Sensing at the water neck presents the same problem. Sensing it in the radiator tank would be the most accurate for fan control. When I tried an electric fan setup back in the late 80's the kit came with a temp probe/relay pack that you inserted in between the radiator fins to sense coolant temp in the radiator. It was adjustable and had a connector for the A/C (if equipped) for fan override. It never cooled well (but the fan controller worked OK) so I pulled it and went back to old school. I still have the controller and I'm thinking about giving it a try again now that there are much better electric fans available today.

But the best thing would be an in-tank sensor, IMO.

Agreed. That's why I posted the link to the in-line temp sensor above. I think it's a much better way to set it up.  If your fan sensor is measuring the coolant temp at the engine and BEFORE the coolant goes through the rad, it is always going to reading "hot" and will always want to kick on the fan, whether it actually needs to be on or not.  But by having the fan sensor measure the coolant temp as it exits the rad, you will get an accurate reading of the actual temp of the coolant after it's had an opportunity to be cooled by the air going through the rad and your fan will only kick on if the exit temp of the coolant is above the temp you have designated.  It's not only a more accurate way to measure the coolant temp, but will also save a lot of unnecessary wear and tear on the fan because it's won't be running nearly as much as it would be if you are taking the temp reading at the engine. 
 

 

3/17/2019 6:51 AM  #34


Re: tapping thermostat housing

1fststang wrote:

You would think Edelbrock would consider an extra fitting somewhere since they design and build these with performance in mind.

They have with the new ProFlo4 EFI manifolds, just sayin'....

 

3/17/2019 8:57 AM  #35


Re: tapping thermostat housing

I was just at an IA airplane mechanic renewal seminar where one of the speakers was from Cam Guard. One of the things he pointed out was that they had the most trouble with direct fuel injection systems contamination around the valves. He didn't elaborate.


70, ragtop 351W/416 stroker Edel Performer heads w pro flow 4, Comp roller 35-421-8. T5
 

3/17/2019 10:09 AM  #36


Re: tapping thermostat housing

351MooseStang wrote:

I've thought about going to electric fans but the thing holding me back is the 'fan logic'. As long as the radiator is cooling properly the thermostat keeps the engine below its rated temp. This means that the best way to monitor the temp would be to have the sensor in the radiator itself. That way when the coolant in the radiator drops below the sensor rating, the fan(s) switch off. It should remain this way until the thermostat opens and exchanges block water for radiator water, when the temp rises above the sensor rating. The problem for me is putting a hole in a perfectly good radiator before it needs a rebuild.

Sensing off of the engine temperature would be a bit of a problem because you aren't sensing the actual state of the coolant in the radiator. Sensing at the water neck presents the same problem. Sensing it in the radiator tank would be the most accurate for fan control. When I tried an electric fan setup back in the late 80's the kit came with a temp probe/relay pack that you inserted in between the radiator fins to sense coolant temp in the radiator. It was adjustable and had a connector for the A/C (if equipped) for fan override. It never cooled well (but the fan controller worked OK) so I pulled it and went back to old school. I still have the controller and I'm thinking about giving it a try again now that there are much better electric fans available today.

But the best thing would be an in-tank sensor, IMO.

I like your thought process. To add more questions than answers, is there something like a thermocouple that can be secured to the tank or fins?? For those running a standard transmission with a trans cooler in the radiator, could that trans cooler be used. One end would require an adapter to get from the inverted flare to the temp sensor. On the other end, add a valve to allow the cooler to be filled with antifreeze. Would the heat transfer be quick enough to maintain proper operation?? Food for thought.
 


John  -- 67 Mustang Coupe 390 5 speed
 

3/19/2019 1:26 AM  #37


Re: tapping thermostat housing

Bolted to Floor wrote:

351MooseStang wrote:

I've thought about going to electric fans but the thing holding me back is the 'fan logic'. As long as the radiator is cooling properly the thermostat keeps the engine below its rated temp. This means that the best way to monitor the temp would be to have the sensor in the radiator itself. That way when the coolant in the radiator drops below the sensor rating, the fan(s) switch off. It should remain this way until the thermostat opens and exchanges block water for radiator water, when the temp rises above the sensor rating. The problem for me is putting a hole in a perfectly good radiator before it needs a rebuild.

Sensing off of the engine temperature would be a bit of a problem because you aren't sensing the actual state of the coolant in the radiator. Sensing at the water neck presents the same problem. Sensing it in the radiator tank would be the most accurate for fan control. When I tried an electric fan setup back in the late 80's the kit came with a temp probe/relay pack that you inserted in between the radiator fins to sense coolant temp in the radiator. It was adjustable and had a connector for the A/C (if equipped) for fan override. It never cooled well (but the fan controller worked OK) so I pulled it and went back to old school. I still have the controller and I'm thinking about giving it a try again now that there are much better electric fans available today.

But the best thing would be an in-tank sensor, IMO.

I like your thought process. To add more questions than answers, is there something like a thermocouple that can be secured to the tank or fins?? For those running a standard transmission with a trans cooler in the radiator, could that trans cooler be used. One end would require an adapter to get from the inverted flare to the temp sensor. On the other end, add a valve to allow the cooler to be filled with antifreeze. Would the heat transfer be quick enough to maintain proper operation?? Food for thought.
 

I'm sorry for not responding sooner! Family & work, the usual... I dug up the controller that came with the fan I bought in the late 80's because it's like what you are asking about. It was made by Genelco (looks like still in business) and the model code is: MOD 14-8635. It's a small rectangular box (about 2" x 1-1/2" x 1") with two small mounting tabs (mine are broken off long ago) that has the electronics potted inside with five 1/4" male terminal connections, a 2" long x 1/4" diameter thermocouple on a 2' lead coming out of it, and a small potentiometer to adjust the trigger temperature. The five terminals are marked: IGN. COIL, GROUND, +12 VOLTS, A/C CLUTCH and FAN. I used it to trigger a more powerful relay to turn on the fan and while it worked, I never could get the fan to cool enough to know if it would hold and cycle correctly.

I'm thinking about adding another try at electric fans to my long list of things to do on the car. The tech is better now and this controller might be worth trying with better fans.

 

3/19/2019 6:52 PM  #38


Re: tapping thermostat housing

I used the stock OEM style Thermostat housing (cast 'pot' metal) with the pre-drilled port for my Spal electric fan sensor and had no issues with leaks or fan control.  One item to watch out for is the heater bypass hose in these housings are for 3/4" hose, the timing cover is 5/8" hose.  They do sell the bypass hose for this application at the Mustang supply stores. 
The issue I had was the multi-speed Spal controller failed and I installed the DCC controller which has the sensor wedged into the radiator fins, so this port is currently plugged.
BTW - DCC controller has worked quite well.


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

Board footera


REMEMBER!!! When posting a question about your Mustang or other Ford on this forum, BE SURE to tell us what it is, what year, engine, etc so we have enough information to go on.