Compressor running

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

JDiehl

Well-Known Member
Joined
Jan 22, 2012
Posts
60
Reaction score
15
Location
Kansas
Rebuilt my Hitachi compressor and mounted it back up today. The desiccant was white had not turned into a rock or broken apart into dust yet. Pretty sure this is the first time its been serviced at 107K. There were no suspension issues prior but I wanted to change the desiccant and it snowballed to the rebuild. It raises the truck much faster with a lot less noise when operating.

Now, for the but... the compressor will run about every four to five minutes even without a change to the suspension height. I did pull the FoMoCo relay and changed it for one with the rebuild kit from X8R. Checked for leaks and found nothing with soap and water.

Is there anything to check with the iid tool or should I try changing back to the old relay and see if that will fix it up? I'm pretty much stumped not having found any leaks. Ideas?

JD
 

ftillier

Supporting Member
Supporting Member
Joined
Jul 27, 2021
Posts
543
Reaction score
260
Location
Portland, OR, USA
I think reverting the relay change sounds like a good plan, reduce the number of variables you're trying to solve for.
 

djkaosone

'11 LR4 HSE LUX 5.0L V8
Joined
Oct 26, 2015
Posts
1,004
Reaction score
674
Location
SoCal
Did you soapy water spray EVERYTHING, including the 3 valve blocks, compressor, drier, intake/exhaust, tank and struts?
 

JDiehl

Well-Known Member
Joined
Jan 22, 2012
Posts
60
Reaction score
15
Location
Kansas
I need to check the front air block still. Tomorrow I will recheck and change back to the old relay and see what happens.

JD
 

JDiehl

Well-Known Member
Joined
Jan 22, 2012
Posts
60
Reaction score
15
Location
Kansas
Switching back to the old relay stopped it running every few minuets but it did throw a
C1A20-64. Pressure increases too slow when filling reservoir.

I took it for a spin and went to all height levels a few times. It auto leveled at the gas pump and the compressor ran like normal upon start up. Rolled into the garage and went to off road height with no issues or codes.

I did the deep dive with soap and water and still found no leaks. It will sit for a few days now and i again run it through the paces.

Wonder now if it is a valve block internal issue?

JD
 

Cthehentz

Full Access Member
Joined
Feb 24, 2019
Posts
166
Reaction score
65
Location
Las Vegas
I went through this on my LR3, rebuilt the compressor, bought Amazon special that failed, in the end I bought a factory Hitachi compressor and that solved slow to fill warning.
 

Longtrail

Full Access Member
Joined
Sep 3, 2022
Posts
231
Reaction score
112
Location
Ann Arbor
Wonder now if it is a valve block internal issue?

Servicing the valve blocks is really easy; removing the rear valve block being the exception! I'd start with the middle one (just in front of the compressor) as that's the easiest to access; start there and see if it clears your code? This middle valve block also has the pressure sensor for the reservoir; check the wiring. I wouldn't correlate the suspension behavior (going to the different height levels)with the reservoir code. The reservoir is typically filled after the vehicle height is increased since the reservoir is used expedite the raising of the vehicle; note also that ones the reservoir pressure is established (250 ish PSI) then the valve to the reservoir is closed and the system/gallery (read pipes) are purged of high pressure air (I think this is done to reduce overall pressure on the system). Are you confident that the changes to the compressor have not impacted it's ability to create pressure fast enough?
 

JDiehl

Well-Known Member
Joined
Jan 22, 2012
Posts
60
Reaction score
15
Location
Kansas
I might pull the compressor back off and double check that I didn’t twist up the delivery valve spring when I stalled the new one from the kit. The LR hasn’t been driven in a few days. I left it in off road height with zero sagging from the suspension.

JD
 

JDiehl

Well-Known Member
Joined
Jan 22, 2012
Posts
60
Reaction score
15
Location
Kansas
The front and central valve blocks were serviced with new o rings. There was quite a lot of desiccant dust build up. Still need to do the rear. My gallery pressure is building into the 170’s psi range. What should it be? It’s probably the compressor. Who knows has a good source on the oem hitachi?

JD
 

Latest posts

Staff online

Members online

Forum statistics

Threads
36,178
Posts
216,946
Members
30,438
Latest member
MosheFrost
Top