Engine/Transmission (1994 - 1998) went away & came back

[Dick R]

Maybe someone has had the same experence , started truck & let the oil preesure build & proceeded to leave drive way , OPP's , No power brakes and no power steering , nothing , raised hood & see nothing wrong , got back in revved motor to about 1800 RPM , than I had full power again , it came back and has not done it again , what the heck would have caused that to happen ? anyone ?

 

[KingS]

my truck sometimes just takes longer for the pressure to build up to get the brake to work and steering and then other times it work almost right away I notice that it happens more in colder weather.

 

[Dick R]

just does not seem right , running long enough to build oil pressure should be enough time for vacuum to build and the power steering pump being hydraulic should immediate , kind of like the shaft slipped in the gear or something , the repair book I have does not give a break down on any of these units & how the gear is attached ?????????

 

[GAmes]

My guess is the tiny screen filter in your P/S pump is clogged. I don't have it handy but there is a very good thread on removing and cleaning it. I had the same problem, did the service and replaced the P/S fluid. I now replace the fluid every 100k. It hasn't done it again in the last 250k miles. By the way 98 brakes don't use vacuum for assist.

 

[Dick R]

thanks for the tip on the power steering , will dig into & see what I can find on the forum pertaining to the filter screen , what has the 98 got for boost on the brakes , I put my foot down hard on the pedal and it acted like their was a vacuum failure hardly any brake at all , then everything came back normal after I revved it ???????????

 

[GAmes]

what has the 98 got for boost on the brakes

What else, power steering pressure :-laf



Here's the link



https://www.turbodieselregister.com/forums/showthread.php?t=69047&highlight=power+steering+pump

 

[Dick R]

Well I would guess the vacumn pump is ok , I see now that the trucks were changed over to hydraulic boost on the brakes starting in 97 , must be powered off the power steering pump ?

 

[GAmes]

... ..... must be powered off the power steering pump ?

I said it first :-laf

 

[Dick R]

thanks for the link should help allot , had the steering box changed to a different delphi unit a few years back & never seemed to have full power on steering has more in put on the steering wheel before it activates , got rid of the pitment arm slop though , maybe the mechanic got some dirt in the lines ?

 

[GAmes]

... ..... maybe the mechanic got some dirt in the lines ?

Could be, but I don't think so. The screen is pretty small. If you stretch the spring a little it will make steering easier. Just don't stretch it too far.

 

[Glock Guru]

Sorry I thought the topic was about a ex-wife or somthing.





-Troy

 

[RPosey]

Power brakes 95'

I have had the brake no power situation before, several times. It was usually when Idling and pressing the brakes, it must have depleted the vacuum. I did notice the large vacuum hose coming from the booster had a kink in it. I straightened the hose as best as I could and it hasn't happened in a long while.

 

[DieselDoghouse]

I would be suspicious of your hydroboost. You've got a '98 I'm guessing you not running vacuum-assisted brakes! The hydroboosters have always been cantankerous on our trucks. They behave like hydraulic steering on some tractors—a priority valve ensures brake assist, and the 'overage' is passed to the p/s gear. Hence the three lines:



Hydro in

Brake return line to pump.

'bypass' to steering.



If one of the small metering valves inside the booster hung up and pressure was shunted from input to the return: no internal pressure for brakes AND no bypass to steering!

Pretty sure I had this happen myself right before the seals let go and the unit started puking fluid - and got replaced. Also - had a Mopar partsguy tell me all the G2 Hydroboosters supersede each other by years - the newest fits ALL previous. I haven't been able to verify.

 

[Dick R]

thanks , the system on my truck is hydraulic not vacuum as I thought , I did find a puddle of oil under the truck , if this came from the brake & steering system where does it puke out from ? I have not had this problem only once and I did have to add fluid .

 

[GAmes]

Clean the bottom of the reservoir and the line fittings, refill with fluid and start it up. On mine the reservoir started leaking where it attaches to the pump and drips off the bottom. (It also leaks without the engine running) If it is a line fitting you should be able to find it. The pump/reservoir has a seal kit available, I'm getting one tomorrow and can give the number to you if you need it.

 

[Dick R]

cleaned the engine & compartment and completely degreased the power steering pump , now I should be able to see if it leaks and where , not much room to work on it if it needs resealing , if it does I could use the part number for the kit . thanks