Hard pedal

[RustedRanger]

After driving and sutting off my truck for more than an hour or so the brake pedal is hard(no vacume). Could this be the booster leaking or a bad check valve?

 

[hondaxr650]

Could be either. I had the same probem. Replaced the check valve and the problem was solved.

 

[srteach]

Do you mean no vacuum with the engine running after sitting for that long?

1. Pull the booster brake hose with the engine running. Should have vacuum.
2. Put hose back into the check valve with engine running. Remove check valve from booster. If you have vacuum, check valve works (at that moment).
3. Do you hear a hissing (sucking) sound close to the booster? Bad booster is likely.

If you want to replace parts, start with the least expensive, but make sure you have vacuum in the booster hose first.

 

[RustedRanger]

Thanks for the info y'all. I got the check valve and grommet yest but still need a new piece of hose since the original is cracked pretty good. I know this is something simple but I guess I have been blessed in all my cars/trucks not having a problem with a brake booster.

 

[RustedRanger]

I changed the check valve,vacume hose and the grommet. It does seem to run better so I think the grommet was leaking some....it had some cracks. But....the pedal is still hard after it sits awhile. Thanks for the advice/info.

 

[alwaysFlOoReD]

I'm thinking this might be normal. You have a hard pedal because the vacuum assist is not working when the engine is off. No assist = hard pedal. Put your foot on the brake while not running, if the pedal is hard=good, if your foot sinks a bit= need to bleed brakes or master or slaves should be looked at. With your foot on the brake start your engine, you should feel the pedal sink slightly= good, your vacuum assist is working.
Hope this helps,
Richard

 

[RustedRanger]

Kinda funny that I didn't notice this before,I think because where I park at home is on gravel with the front wheels in a slight dip so I don't use the brake when I start it at home. When I changed the parts I also "blanked" out the computer. It does run noticeably better. So I'm thinking the hose/grommet might have had a small leak while running. The pedal is hard and firm if it sits for awhile and goes right down when I start it and it don't change the idle speed when I hit the brakes. Thanks again.

 

[alwaysFlOoReD]

The pedal is hard and firm if it sits for awhile and goes right down when I start it and it don't change the idle speed when I hit the brakes. Thanks again.

It shouldn't go all the way down, that would lead me to believe it needs bleeding. If you bleed, start at the tire farthest from the master.
Richard

 

[RustedRanger]

By "going down" I mean the pedal goes down to where it should be. When shut off the pedal is just hard to push. The pedal when running is normal as far as distance to engage the brakes.

 

[alwaysFlOoReD]

 

[RustedRanger]

I think the seal might be worn around the rod from the pedal to the booster. I swept out my truck yesterday and while I was doing that I sprayed some WD-40 on the rod,started it and worked the pedal. I was at my dad's when I did this and on the way home I noticed I had more brake pedal.