'91 P30 Forward Control Chassis w/faulty Autopark

[cruzinbob]

I have a 1992 Coachmen Motorhome on a GM Forward Control Chassis (˜91). It has a problematic hydraulic system. "Autopark" ties together the Brakes, Emergency Brake, Park & Power Steering. I've spent over $4000 in the last year and it's not fixed yet!

Have replaced all parts associated with system - power steering, hydro boost brake cylinder, steering box, & park control valve.

Apparently air gets in and bleeding the lines is difficult.

Any knowledge and reference help is greatly appreciated.

[cruzinbob]

I have a 1992 Coachmen Motorhome on a GM Forward Control Chassis (˜91). It has a problematic hydraulic system. "Autopark" ties together the Brakes, Emergency Brake, Park & Power Steering. I've spent over $4000 in the last year and it's not fixed yet!

Have replaced all parts associated with system - power steering, hydro boost brake cylinder, steering box, & park control valve.

Apparently air gets in and bleeding the lines is difficult.

Any knowledge and reference help is greatly appreciated.

[DriVer]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by cruzinbob:
Any knowledge and reference help is greatly appreciated. </div></BLOCKQUOTE>cruzinbob, We have a number of posts from a member called "oldusedbear". We believe he is probably one of the best resources regarding the P series and the J71 autopark system. See if you can use our "FIND" function and type in oldusedbear in the search window.

Thanks for joining us on iRV2.com.

[parts_expert]

which valve did you replace? there is a primary valve and secondary/relay valve

[cruzinbob]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by parts_expert:
which valve did you replace? </div></BLOCKQUOTE>

Park Control valve, part was $699.00, labor $285.

I'm posting an addition to this thread, see below.

AND, THANK YOU DriVer for your quick and efficient reply.

[cruzinbob]

There is a LOT of discussion on several forums about this problem.

This is about a problem I've experienced with the Autopark system in a 1992 Coachmen Motor home on a GM Forward Control Chassis (˜91). It has a problematic hydraulic system. "Autopark" ties together the Brakes, Emergency Brake, Park & Power Steering. I've spent over $4000 in the last year and it's not fixed yet!

I have no power steering, power brakes, emergency or park for transmission. Park light will not go off.

Chassis = M-340 MB Chev, 48,000 miles.

VIN 1GBKP37N4M3315805.

After having 4 different mechanics work on it, including Barber RV in Ventura, CA (could not even begin to diagnose), I found a dedicated shop owner (Ventura RV Specialist, Scott Ross) who has lost labor costs in tracking down the defects in the system.

I'm still having problems however which started just after having the transmission replaced. Improper bleeding of the system may have caused a problem in one of the recently replaced parts.

I have now been in contact with Helmcs@Helminc.com . I contacting GM but found no relative Dept. I rephrased the problem and they email this:

"I apologize listed is the item number and price for the service manual shipping and order processing will occur taxes may apply. $135.00 ST-330-91K 1991 R/V/P Truck Shop Manual Kit"�.

Today I went to a local GM dealer and the parts man kindly printed schematics of the Autopark system. While there I questioned Service about their bleeding procedure and was told they lift the front wheels off the ground and MANUALLY (key off) turn the front wheels back and forth which bleeds (removes air from) the line. Bleeding from the reserve tank opposite the parking brake drum will not suffice. This is about the 5th different technique I'll have witnessed once we try today.


I'm about to pursue legal action and would like each one of you to contact me in this effort.

Bob Scott
1591 Spinnaker Dr, Ste 114
Ventura, CA 93001
cruisinbob@juno.com
805 256 5305.

[oldusedbear]

Hi Bob - - I just got an email from you too. We may very likely be able to help you with the portion of that system that pertains to AutoPark. We can't help you much with the Hydroboost or power steering, but the problem could very likely BE with the AutoPark.

There is a condition known as "overtravel" that can just give you fits - - Until cured, you will never get the AutoPark OR PS and PB bled!

There is waaay to much info involved to pass it back and forth in these small forum boxes. But I'll respond to your email ans see what we can figure out. I'm currently working with someone else that has exactly the same problem - - so you are not alone.

We'll try our best to help you and look forward to tackling the problem

oldusedbear

[cruzinbob]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by oldusedbear:...you are not alone.

We'll try our best to help you and look forward to tackling the problem

oldusedbear </div></BLOCKQUOTE>

Wow, it never ceases to amaze me at how lucky we are with the internet and it's experts! Thanks bear