View Full Version : Bendix vs Kelsey Hayes Systems

01-05-2017, 10:10 PM
Over the years, there has been considerable conversation about just when did Ford decide to start manufacturing Squarebirds with the under the hood Bendix system instead of the under the dash KH system. From what research John~Jopizz, Dave~simplyconnected and I have done the following seems to be true. But we are not sure.

According to my limited research, the 1958 Squarebird had the KH under the dash bellows system on it, regardless if it had AC or not. Below I will post a copy from the '49-'59 Ford Parts Catalog and the Text Catalog. That same Text indicates that in 1959 Ford switched to the under the hood Bendix system. However, it is our understanding that this did not occur until late in the '59 production run. There is no date listed there when this took place. Up til then, there are '59's coming off the production line with KH bellows under the dash units. We have not been able to find a date when this change took place. If anyone has this information, we would appreciate knowing it.

In another page from the '49-'59 Ford Parts Catalog you see a page that shows the Bendix system for the '59 Squarebird. I did not find one showing the KH bellows system, but I might have overlooked it. Then I looked through the VTCI Squarebirds OFS CD for any information regarding when this change might have been made. But I did not find anything. Alan Tast, on this Forum, who had much to do with writing the Squarebirds OFS, just told me that he does not have the complete set of Technical Service Bulletins for 1959/1960. He said that in the TSB's, starting in January 1959 and running through the end of that year for the Squarebird, there might be one that tells us the date when they make the switch from the KH Bellows under the dash to the Bendix under the hood system. I know that Alan would love to have that date to complete his research on this, and us also.

In the Squarebirds OFS in Section, Brake Booster & Vacuum Check Valves, 1958-1960, you will see that the 1958 had only the KH Bellows under the dash type system, whether or not it had AC. Then things changed in 1959. In the 1959 352, in early production, the car with NO AC had the KH Bellows in place, Part #B8S 2005-A, FD 7752-59, Page 6. The same applies to ALL engines WITH AC. During the late production of the 1959, Ford switched to the under the hood Bendix system B9SS 2A025-A, FD 7752-60, Page 11. In 1960, according to the OFS, on the 352 with NO AC they switched to the Bendix B9SS 2A025-A, same FD #. On the 430, they used B9SZ 2005-A. In early production on ALL units WITH AC they used the KH Bellows B8 2005-A. During the latter production run of the 1960, they used the Bendix B9SS 2A025-A r/b Adapter Kit Used and B9Sz 2005-A. Finally, during the late production run of the 430 equipped Squarebirds, they used the Bendix B9SS 2A025-A, Adapter Kit Used. This is that adapter kit that is like unobtanium, seldom every found. You will see a picture on the left with a Squarebird with AC with just the MC under the hood, and connections leading to the KH Bellows unit under the dash. On the right a 1960 with the Bendix system and the Adapter Kit in place, on an AC equipped Squarebird.

Any additional input you can provide, is appreciated. Especially if you have a full set of TSB's for 1959. Also, if you can provide us with the VIN number and Build Date of your 1959 Squarebird, with just a single MC, and a KH Bellows under the dash, WITH AC, and the single MC/Bendix under the hood, on an AC equipped Squarebird, we might be able to better determine at exactly which date or date range this change went into effect... For example: My '59 YellowRose has a VIN# of 132112 indicating she was the 32,112th Squarebird built with a Build Date - 21C = 21 March 1959. This puts her midway through the 1959 Production run. She left the factory with 352ci engine, AC and the KH Billows under the dash. Production started Oct. 3, 1958 and ended Aug 22, 1959. Total 63A Hardtops produced = 57,195. Let us know if your Squarebird is an OEM Original Squarebird, if you know. Feel free to post just the serial # and the Build Date as I did and I will compile the data from there. Here are those pix.

01-06-2017, 08:24 AM
1959, 352 with AC, Serial 152151, built 06-19-59. Has KH under-dash bellows.

01-06-2017, 09:38 AM
Wow, Mike! That was a bit of a surprise to me! Your Squarebird was manufactured about 2 months before the end of production on Aug. 22, 1959, and it has the KH bellows unit on it! I thought, perhaps, by then, they might have already changed over to the Bendix unit, but apparently not! It will be interesting to see what shows up next. As I recall, you know that your Squarebird is an OEM original when you obtained it. Am I correct? Thanks for posting! I have started building a database on this information. So far, just mine and Mike's are in it!:D. Thanks, Mike!

01-06-2017, 09:47 AM
Yep. Bone stock, except Pertronix ignition.

01-06-2017, 11:40 AM
All 59's with A/C had the under dash booster. I think Ray is looking for non-A/C 59's that have the Bendix under hood booster.


01-06-2017, 12:11 PM
We are trying to determine the date, in 1959, on AC equipped Squarebirds, when Ford made the decision to stop using the under dash KH bellows unit and switched to the single MC/Bendix booster unit under the hood. According to the VTCI Official Factory Specifications (OFS), all early production 1959 Squarebirds with AC left the factory with the KH bellows unit under the dash in them. But sometime late in the production run of 1959 AC equipped Squarebirds, Ford made a change to the under the hood single MC/Bendix Booster unit. Who has a 1959 with a 352 or 430 with AC that has the MC/Bendix booster under the hood and what is the serial number and the Build Date on the Data Plate?

01-06-2017, 03:55 PM
I don't think you'll find any 59's with A/C that left the factory with the Bendix booster. The brake booster mounting kit for the Bendix was only available for the 60's (C0SZ-2A251-A). The 59 kit was Air Conditioner Installation Kit SK-B9SF-17900-G and no booster mounting kit was listed for the 352 or 430. This booster kit does appear as part of the Air Conditioner Installation Kit SK-C0SF-19A873-N. (1960)
All the 60's I've seen with A/C had the K-H under dash booster. The kits referenced above I'm sure were for dealer installations, and if you can find an original 60 with the Bendix booster, it would have the mounting kit installed and been added after production. To find a 59 with the Bendix and A/C would mean someone added the kit from a '60.
The details of these kits are in the Osborn Electrical assembly manuals.

01-06-2017, 04:00 PM
There is a date when the non A/C cars switched from K-H to Bendix and we might have more success finding that window by member response with Year, Engine, and Serial.

01-06-2017, 04:43 PM
Hi Carl, and thanks for the information. You may be right. Over the course of the years that I have been on this Forum I have received tons of pictures of 1959 Squarebirds. I could have sworn that some of them showed engine bays with the AC plenum box on them, and the single MC/Bendix booster next to it under the hood. I could be wrong and it would take me a ton of time to search every '59 Tbird engine bay picture I have on this PC to find them.. Going by the VTCI OFS, it indicates to me, rightly or wrongly, that sometime in the latter stages of 1959 production Ford did make a change from the KH unit to the Bendix unit on Tbirds leaving the plant with AC. I could be wrong, and perhaps Alan or "Fuz" can throw some light on that. Hopefully, more of our '59 owners out there will tell us what they have on their latter production '59 AC equipped Tbirds...

01-11-2017, 12:33 AM
After going through a ton of pix looking for '59 and '60 Squarebirds with Bendix under the hood systems on AC equipped Squarebirds, I have found no '59's like that. What I have found is '59's with AC with the KH under the dash systems in every case. Regarding the '60's, I have found some pix with Bendix under the hood systems on AC equipped '60's. However, the majority of them also have the KH system on them instead. After re-reading the OFS specs cited below, I see that ONLY the KH system was installed at the factory for '59 Squarebirds. I mis-read it. It seems most, and perhaps all, of the AC '60's left the factory with the KH system in place. Those that had the Bendix might have been put on at the dealership or by the owner. If I understand that OFS listing correctly, in 1959, the Bendix was introduced late in production and might have been installed on Squarebirds with NO AC... In 1960, it was introduced in the late production run and might have been installed on 352 and 430 AC equipped cars using that AC adapter mounting bracket to clear the AC plenun box, before production ended. IF I read that chart correctly.

01-12-2017, 02:45 AM
I would like to hear from anyone who owns a 1959 or 1960 Squarebird that is equipped with factory AC that they KNOW to be an original Squarebird that has not had the AC system modified since it left the factory. Thanks!