Forte Hydroboost / Wilwood MC pushrod length

[Rian_Colorado]

Well hell.... After the successful start, I tried to "once around the parking lot".

NOPE

Felt like something was dragging or rubbing pretty hard.
Put it back up on the lift, shut the motor off
Put it in the air and rotated each wheel - seemed to turn freely enough.
Started the motor (hence turning the pump - and pressurizing hydroboost + power steering)
Tried to turn the wheels again, and the brakes are DEFINITELY engaged somewhat - like basically the hydroboost must be putting pressure on the MC. Both front and rears dragging pretty hard.
Checked that there was no interference with the brake pedal, all is fine there. Small amount of play with pedal fully extended

Searching leads me to believe that the pushrod might be too long?

I would have assumed that would have been setup for the appropriate length before it was sent out, but maybe I'm wrong....

Pulled out the pushrod (Oh joy, I'll get to re-bleed the brakes!)

As near as I can tell with a set of digital calipers, the TOTAL void space (room between MC to mating surface, + HB to mating surface ) is 4.5335.

I'm assuming that the total length of the pushrod needs to be 4.5335 minus .020 - .050? (so total shaft length of 4.5135 to 4.4835?)

Shaft as installed when I removed it was 4.5605 - so slightly longer than the available space by my crude measurement. This makes logical sense to me based on what was happening with the brakes....

https://thefactoryfiveforum.com/attachment.php?attachmentid=218228&d=1756508187

Curious what others have found when/if they setup their pushrods or had similar issues?
I've ordered a more precise measuring tool that should be here before the weekend. Amazon loves the 30 purchases of 11$ I make every month.... lol.

Anyone have record or remember what the total length of theirs was?

Hope everyone is set to have a great holiday weekend!

Rian

[Lidodrip]

Hello Rian,

I have the same setup from Forte and my pushrod was adjusted too long and caused brake drag just like you are experiencing. I did not measure the final length of the pushrod, but I did end use a pushrod adjuster tool that I bought on Amazon - https://www.amazon.com/Upgraded-Adjustment-cylinder-Adjustable-Distance/dp/B0CD1LSCW9/ref=sr_1_3?crid=GI8RCXIXJA0V&dib=eyJ2IjoiMSJ9.aTSZkD6PNZcyQh5Sv5BXqoTFQoGZPSQUD m2HW1COPc1jjE0nXeWB20AfO1R7CIecmUv_KnBKEFZmMbzQPPS hbgEz_3VzRRCR5_pz7uiGYpAP8HRudxrwgp77QFrjehDc_-w1cyZNVxcSL7fZKJTSbM4RzBpDUJXUonGmV1d7RAAHN5VV8IXB A4yxjN1GplXhR1kahnSJq8F3u2hwnlGNN-pp3VctB-3r7tgW6VyBGD1oPh2LouMruyikVdLrQnv3vA5WI20xcg7tr4U7 GanZPCBajDFONVZBS6led94o6Co.NAX7NZteRyV62qUzJ4uj_5 XkXQjW-FI-zdVrIyI7hTI&dib_tag=se&keywords=brake+pushrod+measurement+tool&qid=1756521867&sprefix=brake+pushrod+measurement+tool%2Caps%2C111&sr=8-3. This tool worked great and was simple to use (but I did need to file down the measuring rod as it was too long from the factory). Once the pushrod was adjusted properly, the brake drag went away.

The other issue I had with Forte's setup was the clevis that attaches to the brake pedal caused interference that prevented full swing of the brake pedal. This would limit the travel of the pushrod in the MC and thus limit braking ability. Here is a link to a thread about how I fixed it - https://thefactoryfiveforum.com/showthread.php?51624-Trouble-with-New-Hydroboost&p=584298#post584298. The good news is that after the pushrod was adjusted and the clevis interference addressed, the brakes work fantastic.

Feel free to reach out if you need any help. I must admit, Forte's hydroboost system took a lot of work to get working properly.

James

[edwardb]

The pushrod in my Forte provided hydroboost setup was also too long as assembled. That was in Roadster build 7750 back in 2014. Found my notes. The pushrod was .810" too long (crazy) and so long the brakes wouldn't even bleed to a hard pedal because of how car the MC was pushed in. I adjusted it to .020" free play (right in the middle of the suggested range according to my notes) and brakes bled and worked normally. Sold the build two years later, but drove it 5,000 - 6,000 miles as I recall and brakes were fine.