2 IPs, Neither working well enough to drive - Troubleshooting - VWDiesel.net The IDI, TDI, and mTDI source.

• 2 IPs, Neither working well enough to drive by ORCoaster on 18 Sep, 2011 20:54
• Well, I am going to pull what little hair I have left on my head clean out.  Owning a Rabbit is a Harey experience.
  
  Today I just wanted to reduce the internal pressure in the IP pump a bit and check the timing.  Now I have ruined two oil pressure gauges and neither pump on the VW is working.
  
  Pump #1  Was working fine just a bit high at idle.  So I removed the pressure regulator near the front of the pump and tapped it back a bit figuring if I tapped it to far I would just tap it back and use the gauge to tell me when I was near 43 lbs at idle.  I was at 60.  Well tapping on the regulator made the pressure go up not down and it went up so much that when the car raced after startup it pegged the needle so bad it stuck on the 80 lbs side.  I replaced the gauge with another and pegged it out at 120 lbs.  I am surprised I haven't blown the front seal clear out of it. 
  
  So my question here is do I need to tear down the pump and remove something from the internal passages somewhere?  I thought it would be easier to install a second pump but that has issues as well.
  
  Pump #2  will idle but not accelerate well.  If I hold my foot to the floor it slowly gets up to speed and then just takes off to the top of the governor setting.  I have to run out and crank down the smoke screw to get it to slow down.  if I leave the screw at the low end then the pump will never accelerate up.  So I have a pump that will idle or will scream at the top of the RPM range.  But not really function in the middle.
  
  I cleaned screens at the OUT bolt, readjusted the arm on the spindle and tried everything I can think of to get it to run normally.  At this point in time I am baffled.  Anyone have their pumps exhibit this weird behavior? 
  
  Going to have to drive the Pickup back to the big city if I don't get this resolved in the next couple of days.  I may take the one pump with me to tear down over the weekend in Portland.  Then bring it back to here in a week or so and see if I did it any good.  I think it just has a goober in it.
  
  Ideas please?
• #1 by R.O.R-2.0 on 19 Sep, 2011 12:05
• if you need help, let me know.. ive torn quite a few pumps apart. and have a couple good spares too..
• #2 by ORCoaster on 19 Sep, 2011 14:41
• Have you ever had a pump just start gaining internal pressure like that?  Seems like we all have the other problem.   Lack of pressure as the pump wears.  I was even thickening my fuel up with wax for awhile then the pressure seemed to stay high and won't come down on idle. 
  
  Insane, 80 lbs at idle with the pressure pin hammered all the way back out and protruding above the nut.
  
  
• #3 by rabbitman on 19 Sep, 2011 20:47
• Is the little cylinder shaped valve loose in there? I would think wit it backed out that far it should even rattle when you shake it.
• #4 by ORCoaster on 19 Sep, 2011 21:29
• I don't remember it rattling but then I don't remember shaking it either.  Someplace along the line I think I have seen this valve in a cross sectional drawing.  I am not sure having it all the way up and out the top, the pin that is makes it loose enough to rattle.  It just takes less pressure to make the fluid go the other way.   
  
• #5 by burn_your_money on 20 Sep, 2011 10:28
• Did you just take the regulator out and hammer on the end of it to drive the adjuster back up or did you take it apart?
  
  You'll probably need to take it back out and investigate it.
• #6 by rabbitman on 20 Sep, 2011 14:38
• I didn't explain very good, I meant is the spring loose in there. I always pound it in 'til the keeper, plunger and spring fall out then flip it over and pound the tight part back the other way 'til it's flush then reinstall the spring, plunger and keeper.
• #7 by ORCoaster on 20 Sep, 2011 16:43
• I did not disassemble it I just tapped it with a punch upside down.  The spring compressed against the stop and then the pin itself would move.  Is this not the way to do it?  Seems to have worked all the other times. 
  
  If I continued to pound on it doesn't the keeper pin just come out the top?  I didn't think I needed to disassemble it as i was only looking for about a 10 lbs change on the gauge. 
  
  I will look at what I have and see what might be explained above here.
  
  thanks for the tips.  I don't think the VW will be returning to Portland this weekend.  Maybe it needs a time out?
• #8 by fatmobile on 20 Sep, 2011 22:55
• The overflow pressure from the regulator goes right back to the front of the pump.
  
   If there is no pressure on the fuel going into the pump,.. then maybe the passageway relieving pressure from the regulator is blocked,.. piece of o-ring?
  
   I don't think the internal spring can be smashed and block the opening.
• #9 by rabbitman on 21 Sep, 2011 14:57
• Quote from: ORCoaster on 20 Sep, 2011 16:43

  I did not disassemble it I just tapped it with a punch upside down.  The spring compressed against the stop and then the pin itself would move.  Is this not the way to do it?  Seems to have worked all the other times.

  
  It's probably hard on the poor spring.
• #10 by ORCoaster on 21 Sep, 2011 21:39
• I did as Burn your money stated.  This is the accepted method I know.  It might be hard on the spring but it is the only way to get less pressure from that crazy regulator.  Other than buying that funny looking Bosch tool.
  
  I will have time to see this regulator in the daylight tomorrow after work.  Today was a 6 AM to 8 PM sort of shift and no play time. 
  
  
• #11 by ORCoaster on 22 Sep, 2011 21:18
• Just finished pounding on parts.
  
  After a through investigation I think there are several correct diagnoses here.  See if you can find them.
  
  Picture the valve from the top down.  I have driven the pin down to increase the the pressure but drove it too far.  So I take it out and put a punch on the other end that normally goes deep into the pump body and tap on it until the top pin is flush with the top again.  You would think to a near zero pressure position right?
  
  Well what if you are a bonehead and choose the wrong sized flat bottomed punch and actually drive that spring retainer clip up into the body just about all the way.  I could feel the spring compress a little bit but no way was it loose in there and rattling around.
  
  After I was able to drive the spring, lower pin and retaining clip out the bottom I had a heck of a time getting the top pin to return to flush with the top. 
  
  They must be pretty close to the same size, pin and bore.  At any rate if I had compressed the spring nearly all the way and had the lower pin halfway up the bore and stuck there with the retaining pin I think that would just about be a solid block on the opening that allows the fluid to return to the system.
  
  So careful on what size punch you use when you are trying to get the pressure down at idle. 
  
  Now i just have to replace the two oil pressure gauges I toasted by giving them 40 to 60 lbs more than they were rated for.  Ouch.  Good thing is that I may not have to tear into the pump at all now.  No pieces of O ring just a chunk of immovable metal. 
  
  What a dork mechanic I am turning back into.  Reminds me of my teens.   
• #12 by ORCoaster on 30 Sep, 2011 18:05
• Well, I was able to swap back the pump that was causing me grief and it is running smooth.  I had a gauge on the IP but it is now dysfunctional and needs to be replaced.  Maybe in the morning.  It has started raining again on the coast and so I will take the other IP apart another day and see what is up with the accel lever mechanism.  Just to weird that it does flip between the idle full on to the limit high RPMs but won't run in between.
  
  
• #13 by burn_your_money on 01 Oct, 2011 10:54
• Glad to hear you figured out the problem.
  
  Are you sure you have a normal VW governor in there? Has it been modified?
• #14 by ORCoaster on 01 Oct, 2011 20:05
• I am not sure what is under that little lid.  When I get a spare weekend, famous last words, I am going to look into it.  Could be all fouled up and I don't know it.  My son sent me the pump and he bought it as a spare years ago.  Then he tried to use it and it wouldn't work for him either.  I needed a new high pressure side to the IP I was running on my VW a year or so back so he sent me what he had since he no longer had his VW.  I am thinking that either the accel levers, gover assem. or vanes are messed.  I probably just needs a teardown and rebuild.  
  
  Like I said when I get some spare time.  
  
  I picked up an oil pressure gauge this afternoon and set my idle on the IP to 37.5 and am going to leave it alone for now.  At cruise speed it seems to be on the low side of 60s but rap it up to pass someone and I hit 80.  So I will just see how the mileage is over the next couple of tanks.  I have the timing different than before as most tuners have to change something or we just are not happy.