Dallas Area Classic Chevys Message Board Forum Index Dallas Area Classic Chevys Message Board
To post you must register with a valid E mail address. Choose the 'Register' link below this text, complete your registration and soon you will be able to enjoy the features of the Forum. Questions? email - info@DallasClassicChevy.com
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Motor Revs

 
Post new topic   Reply to topic    Dallas Area Classic Chevys Message Board Forum Index -> Technical Help
View previous topic :: View next topic  
Author Message
Dabees0



Joined: 06 Apr 2018
Posts: 3

PostPosted: Thu Aug 02, 2018 10:04 pm    Post subject: Motor Revs Reply with quote

I have a 55 2nd series truck with 383 and camaro front clip. Front disc rear drum setup.

Truck runs great but after a few minutes of driving, when I stop at a light or stop sign the motor starts revving up about 500rpm or more. Once I let off brake and start rolling it goes back to normal or if I put it in neutral it will settle down. It only does this when brake is applied.

Any thoughts or experience with this?
Back to top
View user's profile Send private message
acardon
Senior Contributor


Joined: 12 Jul 2005
Posts: 256
Location: Southlake, Tx.

PostPosted: Sat Aug 04, 2018 3:09 pm    Post subject: Reply with quote

Do you have a power brake booster? Look for a vacuum leak at the booster or a bad valve in the booster. Try temporairly plugging the vacuum line to the booster.
Back to top
View user's profile Send private message
Dabees0



Joined: 06 Apr 2018
Posts: 3

PostPosted: Sat Aug 04, 2018 3:54 pm    Post subject: Reply with quote

Thank you for the response.

I do have a power brake booster. Itís a 7 inch single diaphragm which I would like to switch out for an 8 inch dual diaphragm

How can I check to see if there is a bad valve?
The hard part with this issue is that it only does it when Iím driving and then come to a stop. It hasnít done it when car is in park so I donít know if plugging the line will show me if it has a leak.
Back to top
View user's profile Send private message
acardon
Senior Contributor


Joined: 12 Jul 2005
Posts: 256
Location: Southlake, Tx.

PostPosted: Sat Aug 04, 2018 4:11 pm    Post subject: Reply with quote

You will still have brakes when you plug the vacuum line to the booster. Just have to push harder.
Another possibility would be soft motor mounts causing the throttle linkage to change from the motor shifting.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Dallas Area Classic Chevys Message Board Forum Index -> Technical Help All times are GMT - 6 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group