SAAC Forum

The Cars => 1969-1970 Boss 302/429 => Topic started by: paparazzi on June 20, 2022, 08:39:02 PM

Title: 1969 Boss 429 Temperature
Post by: paparazzi on June 20, 2022, 08:39:02 PM
Has anyone ever confirmed the actual water temperature on a 1969 Boss 429 when the gauge sits squarely on the "H"? I am just wondering what the actual temp should be when gauge is on "H"? I am new to this car and  have tried changing the sensor and now trying to confirm if the gauge is bad.
Thanks, Bob
Title: Re: 1969 Boss 429 Temperature
Post by: C6ZZGT on June 20, 2022, 10:46:55 PM
You should be checking the ohms of the sender .............
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on June 21, 2022, 07:59:55 AM
It should also be mentioned that ONLY the AUTOLITE or MOTORCRAFT senders are accurate. ALL the aftermarket senders are calibrated wrong and read too high. They are both obsolete and command significant premiums now, when you can still find them.

Measuring the OHM's of all of them is the only way to calibrate them.
Title: Re: 1969 Boss 429 Temperature
Post by: Royce Peterson on June 21, 2022, 06:12:24 PM
Even some of the Motorcraft senders are way out of specs. Be sure to get one with the red insulator around the center stud. Anything else will be a waste of your time and money. Autolite or early Motorcraft work.
Title: Re: 1969 Boss 429 Temperature
Post by: paparazzi on June 21, 2022, 09:30:36 PM
Thanks for all of your helpful comments. Would this apply to 428 Cobra Jets also? I assume the gauges are all the same? Any suggestions on where I might find the correct sending unit?
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on June 21, 2022, 10:12:12 PM
Post a wanted ad. They are obsolete and not a common everyday occurrence. Relatively expensive as well compared to other aftermarket senders.

You're going to need a little luck on this one.
Title: Re: 1969 Boss 429 Temperature
Post by: paparazzi on June 21, 2022, 10:18:36 PM
Thanks again shelbydoug. Just to help with my post, would this be the same sending unit as used in a 69 428 Cobra Jat? If the Boss 429 uses the same gauge then should the sending unit be the same? Thanks, Bob
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on June 21, 2022, 10:39:26 PM
I believe that it is the same.

Just post a wanted ad here. I suspect that you will receive some offers.
Title: Re: 1969 Boss 429 Temperature
Post by: paparazzi on June 30, 2022, 08:24:45 PM
Thanks to everyone for help with the Boss 429 temperature sending unit issue. Especially Shelbydoug and Royce Peterson. I managed to source an OEM part (still seems weird to me I couldn't find an after market that is not correctly calibrated) and it solved the problem. The car will not be driven a lot but at least now I know if the temp gauge gets up to "H" I have a problem. I just keep learning!
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on June 30, 2022, 08:46:06 PM
Quote from: paparazzi on June 30, 2022, 08:24:45 PM
Thanks to everyone for help with the Boss 429 temperature sending unit issue. Especially Shelbydoug and Royce Peterson. I managed to source an OEM part (still seems weird to me I couldn't find an after market that is not correctly calibrated) and it solved the problem. The car will not be driven a lot but at least now I know if the temp gauge gets up to "H" I have a problem. I just keep learning!

It is very strange. Even stranger that the aftermarket manufacturers claim that theirs are correct?

I had to learn the hard way just like you just have.

I'm glad that I could help and it worked out. It's crazy that anyone needs to go find one for $100 on something that should only cost $20.

These days you just can't take anything for granted. You have to check everything yourself which actually adds to your growing knowledge base. 
as a result NO ONE touches my cars. If I get killed in it then it is my fault not someone else's incompetence. ::)
Title: Re: 1969 Boss 429 Temperature
Post by: paparazzi on June 30, 2022, 09:55:57 PM
FYI--my 69 GT with 428 and my 68 GT500KR with 428 also have the sending units with the red insulator just in case anyone ever runs into this on one of those.
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on July 01, 2022, 08:25:17 AM
The red insulator is intended for quick identification of the correct sender since they all look alike at assembly time.
Title: Re: 1969 Boss 429 Temperature
Post by: Royce Peterson on July 01, 2022, 11:58:49 AM
Quote from: paparazzi on June 30, 2022, 08:24:45 PM
Thanks to everyone for help with the Boss 429 temperature sending unit issue. Especially Shelbydoug and Royce Peterson. I managed to source an OEM part (still seems weird to me I couldn't find an after market that is not correctly calibrated) and it solved the problem. The car will not be driven a lot but at least now I know if the temp gauge gets up to "H" I have a problem. I just keep learning!

My experience as well.
Title: Re: 1969 Boss 429 Temperature
Post by: deathsled on July 01, 2022, 12:50:30 PM
Is this general rule across the board including 289 and 302 engines?
Title: Re: 1969 Boss 429 Temperature
Post by: shelbymann1970 on July 01, 2022, 12:53:05 PM
FYI:  Bob got the correct sending unit. Installed it and his temp gauge is working properly now.
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on July 01, 2022, 05:43:30 PM
Quote from: deathsled on July 01, 2022, 12:50:30 PM
Is this general rule across the board including 289 and 302 engines?

Yes. It is the same sender.

With the way companies designate responsibility to some numb nuts lowest entry level engineer to spec it, I would caution everyone that even if Motorcraft for instance decided that there was enough of a market to remake them, I would not be shocked to find that they made them with the wrong  ohm rating as well.

You must realize that these companies are still run by MBA's who will tell you that an item like this is only worthy of a minute or so of their time and assign it to someone with little or no experience in getting it right the first time or aware of the pitfalls of using someone else's data.

You are still better off with an original IF you can find one. It will save you alot of grief, wasted time and energy.
Title: Re: 1969 Boss 429 Temperature
Post by: Bob Gaines on July 01, 2022, 05:57:31 PM
Quote from: deathsled on July 01, 2022, 12:50:30 PM
Is this general rule across the board including 289 and 302 engines?
In 69/70 the GT350 got a green insulator version. 
Title: Re: 1969 Boss 429 Temperature
Post by: deathsled on July 01, 2022, 06:42:13 PM
It is interesting to me how knowledge is so easily lost even with a small passage of time.
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on July 01, 2022, 08:45:22 PM
Quote from: Bob Gaines on July 01, 2022, 05:57:31 PM
Quote from: deathsled on July 01, 2022, 12:50:30 PM
Is this general rule across the board including 289 and 302 engines?
In 69/70 the GT350 got a green insulator version.

I've seen the green one called an F150 sensor.
Title: Re: 1969 Boss 429 Temperature
Post by: rockhouse66 on July 02, 2022, 07:42:06 AM
I have notes from 10 years ago that the Echlin TS6628 will bring the temperature gauge back into range.  I know I installed one with success on my SCJ car.
Title: Re: 1969 Boss 429 Temperature
Post by: deathsled on July 02, 2022, 11:36:35 AM
Here is the Echlin TS6628 at Napa
https://www.napaonline.com/en/p/ECHTS6628
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on July 02, 2022, 12:51:34 PM
Quote from: rockhouse66 on July 02, 2022, 07:42:06 AM
I have notes from 10 years ago that the Echlin TS6628 will bring the temperature gauge back into range.  I know I installed one with success on my SCJ car.

Negative on this. It apparently was revised as well. That was the first one I tried. I thought I blew the engine. Just an inaccurate sender.

Nope. ORIGINAL AUTOLITE OR MOTORCRAFT ONLY.
Title: Re: 1969 Boss 429 Temperature
Post by: paparazzi on July 02, 2022, 05:08:25 PM
One of my aftermarkets was from NAPA but I do not know the part number but I suggest verifying your actual temp against the gauge if in doubt. I just got puzzled again after reading Mr Gaines comment because my 69 GT350 4 speed convertible with factory air, which is supposed to be restored to near factory specs, has a black insulator. Gauge works accurate. Two local old time mechanics and myself learned a new one on this project. We were all ready to call Doug on it :-) Once again better to listen and learn before I speak.
Title: Re: 1969 Boss 429 Temperature
Post by: shelbydoug on July 02, 2022, 08:00:23 PM
Quote from: paparazzi on July 02, 2022, 05:08:25 PM
One of my aftermarkets was from NAPA but I do not know the part number but I suggest verifying your actual temp against the gauge if in doubt. I just got puzzled again after reading Mr Gaines comment because my 69 GT350 4 speed convertible with factory air, which is supposed to be restored to near factory specs, has a black insulator. Gauge works accurate. Two local old time mechanics and myself learned a new one on this project. We were all ready to call Doug on it :-) Once again better to listen and learn before I speak.

;D You found an aftermarket that works?  Share it...but...

"It don't matter to me!"  8)

https://www.youtube.com/watch?v=pl7U2jy1wMQ
Title: Re: 1969 Boss 429 Temperature
Post by: paparazzi on July 02, 2022, 09:43:25 PM
Sorry, None of my after markets worked, including my NAPA. Doug was 100% correct. Me and my mechanics just doubted him  :-[. I was lucky enough to finally find an OEM from someone and it worked..
Title: Re: 1969 Boss 429 Temperature
Post by: Royce Peterson on July 03, 2022, 08:00:53 PM
Two NOS ones on eBay right now:

https://www.ebay.com/itm/255570645138?hash=item3b81329092:g:htAAAOSwSHhf62FM
Title: Re: 1969 Boss 429 Temperature
Post by: Bob Gaines on July 03, 2022, 08:13:05 PM
Quote from: Royce Peterson on July 03, 2022, 08:00:53 PM
Two NOS ones on eBay right now:

https://www.ebay.com/itm/255570645138?hash=item3b81329092:g:htAAAOSwSHhf62FM
59.00 is a fair price for a service replacement Motorcraft sender.  The Autolite marked versions typically sell for well over 100.00 each.