IP Hydraulic Head

[cranetruck]

A little less than a year ago, I replaced the hydraulic head on the IP of my deuce. The engine simply quit running after idling for a short time at a refuling (Joplin, MO).
Today, I took the hydraulic head apart and the conclusion is that fine particles of dirt in the fuel caused scoring and finally binding of the fuel plunger in the bore.

The return spring is not strong enough to return the plunger to its bottom position quickly (takes 10-15 seconds now), so no fuel was delivered to the injectors. Other parts checks out on the head.

Question: Can a lapped surface be restored, see image below for evidence of scoring (Leonard ?)?

 

[Stretch44875]

Just judging from playing with hydraulic valve pistons, and just my opinion, a fine lapping compound would smooth that out. Doesn't look bad, those scratches appear less than a .001 deep.

Dennis

 

[WillWagner]

Yes, class fit parts can be lapped to be renewed. A very fine crokus cloth with the edge taken off and diesel, or Clover extra fine compound will do the trick.

 

[gimpyrobb]

Bjorn, you ever go any farther on this?

 

[rlwm211]

I am curious as to the tolerances of this? I would imagine there is a maximum of what is allowable. I sure would try to polish it up and see if it will work. At this point, you have too many others watching your project with this post.

RL

 

[cranetruck]

Bjorn, you ever go any farther on this?

Well, it has made me acutely aware of the problems that may result from hard rust particles in the fuel. A similar situation is found in the FDC plunger, causing them to leak fuel into the crankcase. I now have a magnetic filter on the 8x8 and posted some results a month or so ago. There is also a MVM article on this, but don't know the issue, maybe current...

 

[gimpyrobb]

I remember the magnet filter and the rust it collected. I have been thinking of making a band of magnets out of computer HDDs for my fuel filters. So you never "polished your rod" and put it back in the hole?

GAWD thats bad!

 

[cranetruck]

Darn Gimp, that's a loaded question, however it moves rather freely now, but I don't trust the scratched plunger. No it was never polished.

 

[southdave]

hehehehehe bow bow cha wow wow, gimp you been in the cheap porno again?

 

[deathrowdave]

Lapped many parts in the energy trade . Both parts should be lapped together , Clover - extra fine- works great , tooth paste will work in a pinch.

Have a great and safe day , Dave

 

[stevegr]

Bjorn, Gimp, et all,

The plunger in my deuces hh will not retract. I've sprayed PB Blaster tapped it back down, spun the engine over, sprayed PB Blaster, tapped it back down and repeat. I'm hoping to work the plunger free by doing that without having to remove the hh.

I have a question on the measured height of the plunger in the hh. Do you happen to know the height of the plunger when it is in the fully up position before removing the hh from the ip (this is assuming it is measured when it is stuck in the up position). I removed the plunger screw, measured the height with calipers as 1.102" from the top surface of the hh to the top surface of the plunger. It would be nice to know what this measurement is for a plunger that has the button intact on the other end. This might enable a person to know if the button has fallen off the end of the plunger without removing the hh from the ip.

Thanks,

Greg

 

[doghead]

Greg, didn't you post this same exact question in another thread today? If so, we call that cross posting and it is against the site rules.

 

[stevegr]

Doghead, yes I did. I should've read the site rules closer. I apologize.

 

[cranetruck]

Bjorn, Gimp, et all,

The plunger in my deuces hh will not retract. I've sprayed PB Blaster tapped it back down, spun the engine over, sprayed PB Blaster, tapped it back down and repeat. I'm hoping to work the plunger free by doing that without having to remove the hh.

I have a question on the measured height of the plunger in the hh. Do you happen to know the height of the plunger when it is in the fully up position before removing the hh from the ip (this is assuming it is measured when it is stuck in the up position). I removed the plunger screw, measured the height with calipers as 1.102" from the top surface of the hh to the top surface of the plunger. It would be nice to know what this measurement is for a plunger that has the button intact on the other end. This might enable a person to know if the button has fallen off the end of the plunger without removing the hh from the ip.

Thanks,

Greg

The best advise here would be to have you remove the hydraulic head.
The plunger moves about 1/4 inch and rides on a cam. If the cam lobe is sitting in the "up" position, you cannot force the plunger down...

 

[scrapdaddy]

Not to hijack, just add. Bjorn do you agree that the plunger should move all the way through without tighting up. the scuffed end of your plunger in the pictures, should it slide all the way through. Mine is binding on that end. Looking at mine, it's nice and smooth. Not totally sure yet if I should work on getting it to slide better. meaning after it is taken apart, on the bench.

 

[cranetruck]

Not to hijack, just add. Bjorn do you agree that the plunger should move all the way through without tighting up. the scuffed end of your plunger in the pictures, should it slide all the way through. Mine is binding on that end. Looking at mine, it's nice and smooth. Not totally sure yet if I should work on getting it to slide better. meaning after it is taken apart, on the bench.

Ron, it's not meant to slide all the way through, if it is smooth over its intended range of movement, you are good to go IMHO.