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Topic: Broke down (Read 3580 times) previous topic - next topic

Broke down

My first big trip. Not going well :( did a stupid this morning and had to replace 2 tires on my RAV4. Got that squared away and got about 150mi south. Coming down the grade into weed CAI noticed the Temp going UP, coming down a grade it seemed odd so I pulled over. When trying to stop, as soon as I took my foot off the brake, the coach accelerated. Even after I stopped and put on the air brake, if it was in gear it wanted to creep. Put it in neutral, no accelerator, RPMs jumped to 2000. Foot on the break, normal Idle. Shut everything down and heard a whistling sound from the back. Opened the Engine hatch but could not find anything.. Sound stopped after a min.. let everything sit for about 10 min.  Eng starts normally. Idles fine for a min then jumps to 2k rpm again. Started down the road. Temp started going up again in 6th. stepped down to 5th and ran at 55mph(2krpm) temp ran just above 220F but did not get higher..
Is this a cruise control issue? did I overheat the eng? The coolant temp light was on at about 250F
There seems to be NO diesel Mech in the weed area:(
Any help appreciated!
Joe

Re: Broke down

Reply #1 –
The spring came off our throttle linkage at the injector pump once.  That raised the RPM some but not 2000.      That was on an 8.3 though.

Re: Broke down

Reply #2 –
Quote from: Bob & Sue –
The spring came off our throttle linkage at the injector pump once.  That raised the RPM some but not 2000.      That was on an 8.3 though.
I would think that the brake would not drop the RPM's to a normal idle :( Thanks.

Re: Broke down

Reply #3 –
If you have a King control, with the brake on the King will only give you 1/3 throttle. I
would do as Robert said and check your return springs. I imagine you have a 8.3 Cummins.

Re: Broke down

Reply #4 –
Your stupid thing was that you forgot to put the key in and in the accessory position. Right? I did that on our RAV4 but caught it after about 10 miles. Our steering locks about 2 degrees off straight ahead, enough to scrub the tires a bit.

Pierce

Re: Broke down

Reply #5 –
I had the cruise stick on ours a couple of times many years ago.  The first time it happened when going up a small grade with the cruise set at 75.  It stuck at wide open.  Didn't know it until I noticed the speedo pass 80 on the other side of the hill.  We were on I-8 in western AZ where it was pretty flat and straight. 
Stepping on the brake exhausts the air out of the Bendix cruise but when released the throttle would go back to WOT.  Turning the engine off after holding the brake for a bit worked the first time.  The other time turning it off didn't work.  I remember fiddling with the cruise control and throttle on the front wall under the bed and then it was ok (maybe just coincidence).  No overheating, though.

Re: Broke down

Reply #6 –
Quote from: Pierce & Gaylie Stewart –
Your stupid thing was that you forgot to put the key in and in the accessory position. Right? I did that on our RAV4 but caught it after about 10 miles. Our steering locks about 2 degrees off straight ahead, enough to scrub the tires a bit.

Pierce
No, LOL, Left the emergency brake on for 4mi of gravel road. Yup..........Stupid. $350 and 2 new tires later......... on the road! till this

Re: Broke down

Reply #7 –
Joe,

More details would help with long distance guesses on what is going on.  What engine do you have?  What type cruise control (Bendix or King)?  Do you have a air throttle?

Re: Broke down

Reply #8 –
Start with the simple things.

Look at your pedal, does it move freely? Can it operate without sticking? Are you traveling with someone? If so, have them push the pedal and see what movement occurs on the engine, there should be something moving.

With the engine cooled down for 15 to 20 minutes at least, check your coolant level. Then start tracing the piping and see if there are signs of any leaks. You may also want to consider starting to source a thermostat. If the weather is warm though, you can pull your thermostat if you think that it is not working until you get to a place that has one.

Re: Broke down

Reply #9 –
Quote from: Chuck & Jeannie –
Joe,

More details would help with long distance guesses what is going on.  What engine do you have?  What type cruise control (Bendix or King)?  Do you have a air throttle?


A 95 U240 would have come with a Cat 3116 with Bendix cruise and air throttle.

Re: Broke down

Reply #10 –
Quote from: Dave Larsen –
A 95 U240 would have come with a Cat 3116 with Bendix cruise and air throttle.
Thanx Dave.  I just ask in case something has been changed from the original factory configuration.

If trouble is suspected with the Bendix Cruise Control system, it can be disabled temporarily by pulling the fuse under the dash.  On our '93 U280 the 15A fuse is labeled "ETHER CRUISE".  The air throttle will still work normally with the Bendix disabled.  See the diagram below for the Bendix components and how they integrate with the air throttle.

Re: Broke down

Reply #11 –
Sounds like the RV1 pressure reducing valve is stuck if it is in fact a Bendix. It's on the firewall and looks like this.

Re: Broke down

Reply #12 –
Quote from: Twig –
Sounds like the RV1 pressure reducing valve is stuck if it is in fact a Bendix.
Respectfully disagree.  The RV1 is a simple pressure regulator.  It supplies 60 psi to the solenoid assembly on the CA-1 Control Module.  OP says "Eng starts normally. Idles fine for a min then jumps to 2k rpm again".  A "stuck" pressure regulator would not cause the engine RPM to start out at normal idle and then suddenly jump up to 2000 RPM.

MY guess (and it's only a guess) would be a fault in the CA-1 Control Module or a fault in the electric potentiometer on the end of the CC-5 air cylinder.

I hope I'm wrong, because both of those components are, AFAIK, pretty much unobtainable.

Re: Broke down

Reply #13 –
I'm using GM ride height sensors for Microsquirt tps signal  .
It is a potentiometer that may work for a pedal sensor , if the oe is NLAv

Re: Broke down

Reply #14 –
Quote from: Chuck & Jeannie –

MY guess (and it's only a guess) would be a fault in the CA-1 Control Module or a fault in the electric potentiometer on the end of the CC-5 air cylinder.

I hope I'm wrong, because both of those components are, AFAIK, pretty much unobtainable.


The cylinder and pot may be unavailable fro Bendix, but they're common in industrial applications.  Festo is my go to source for that sort of thing because of their modular design systems.  i.e you can mix and match pieces until you get what you need to put the cruise control back in service.

Re: Broke down

Reply #15 –
Quote from: Chuck & Jeannie –
Joe,

More details would help with long distance guesses on what is going on.  What engine do you have?  What type cruise control (Bendix or King)?  Do you have a air throttle?


'95 U240 Cat 3116
Don't know on the Cruise.
Air Throttle?

Re: Broke down

Reply #16 –
Quote from: Chuck & Jeannie –
Thanx Dave.  I just ask in case something has been changed from the original factory configuration.

If trouble is suspected with the Bendix Cruise Control system, it can be disabled temporarily by pulling the fuse under the dash.  On our '93 U280 the 15A fuse is labeled "ETHER CRUISE".  The air throttle will still work normally with the Bendix disabled.  See the diagram below for the Bendix components and how they integrate with the air throttle.


Thanks for this.
Am at a truck repair in Yreka, Onarheim towing, but in the run up from Weed everything ran normally.
I will ask them to verify the fluids and get back on the road :) I hope!

Re: Broke down

Reply #17 –
Quote from: Chuck & Jeannie –
Respectfully disagree.  The RV1 is a simple pressure regulator.  It supplies 60 psi to the solenoid assembly on the CA-1 Control Module.  OP says "Eng starts normally. Idles fine for a min then jumps to 2k rpm again".  A "stuck" pressure regulator would not cause the engine RPM to start out at normal idle and then suddenly jump up to 2000 RPM.

MY guess (and it's only a guess) would be a fault in the CA-1 Control Module or a fault in the electric potentiometer on the end of the CC-5 air cylinder.

I hope I'm wrong, because both of those components are, AFAIK, pretty much unobtainable.


You might be right but when I had a run away cruise control, replacing that valve corrected it.

Re: Broke down

Reply #18 –
This may not be a cause but suggest at least trying it. One of the GVs I bought sight unseen in Texas had an issue similar to O P mentions and after driving 3000 miles home with it I took the cylinder apart, greased the parts then put it back together and problem solved.
As mentioned this may not the issue but worth the hour doing it to stop any "stickiness" with seals
Johnh

Re: Broke down

Reply #19 –
Quote from: Twig –
Sounds like the RV1 pressure reducing valve is stuck if it is in fact a Bendix. It's on the firewall and looks like this.

That makes sense.  If that pressure regulator is failing open, the air pressure to the air cylinder operating the governor lever would rise, giving an un-commanded increase in power.