Vacuum Pump Problem

How the engine works

Moderators: Greenleaf, KTA, BC847, Richie O

Vacuum Pump Problem

Postby cmann250 » Sat Mar 24, 2012 12:47 pm

Through some twist of fate, my bottom vaccuum diaphragm fell off and was chilling out on my front cross member. It took the part that goes between it and the vacuum pump body with it and those three bolts are gone/broken/threads pulled out of them. I also believe the pushrod is gone, but the FSM doesn't give a clear picture, so I'm not 1000% sure.

My question is this: Can I make one of these little pushrods? Or is it a Cummins only part? I'm planning on bolting it back up and replacing the pushrod later, because the brakes are as good as they ever have been. I'm betting that diaphragm was bad anyways :roll:

Thanks in advance guys
Caleb, Certified Shade Tree Mechanic Extraordinaire :mrgreen:
The 1stgen.org black sheep

"Whatever!" - Coach Jerry Smith
cmann250
14mm rotor
 
Posts: 4059
Joined: Fri May 20, 2011 5:25 pm
Location: Lafayette, IN

Re: Vacuum Pump Problem

Postby m880cummins » Sat Mar 24, 2012 3:34 pm

I ran into the same problem at Christmas. Two bolts of the piece that holds the pump to the body came loose, broke the flat piece in half and the pushrod slid out. The flat piece is magnesium so if you broke it, mill one out of aluminum. Not sure of the pushrod. I drove 600 miles with the pushrod out and the pump on the crossmember and lost a quart of oil. Not bad. You could hear the timing gears more with the pump hanging. I opted to run the vane pump on mine. I paid $50 for a vane pump at the junkyard, rebuilt it and it was a good swap. If the pushrod is the same length as the one that drives the one on the side I have one leftover.

Charlie
1977 M880 Cummins 5 speed SOLD :(
1985 Crew cab Cummins P7100 NV4500 D60/D80
SUNY Maritime Class of 2017!
m880cummins
fuel screw!!!!
 
Posts: 440
Joined: Tue Nov 15, 2011 2:21 pm
Location: Parkesburg, PA

Re: Vacuum Pump Problem

Postby cmann250 » Sat Mar 24, 2012 4:19 pm

Yea I noticed a new tick from the engine and I think this is the cause. So I may have been running it like this for a few days, and the first thing I did after I discovered this was check oil and I was OK. It's good to know I can run so far with out it :lol: I have a Cummins dealer about 10 minutes away so I'll have a new little pushrod Tuesday. There's no way that I could finagle it back on there without taking the whole thing out of the truck, is there?
Caleb, Certified Shade Tree Mechanic Extraordinaire :mrgreen:
The 1stgen.org black sheep

"Whatever!" - Coach Jerry Smith
cmann250
14mm rotor
 
Posts: 4059
Joined: Fri May 20, 2011 5:25 pm
Location: Lafayette, IN
Top

Re: Vacuum Pump Problem

Postby Mark Nixon » Sat Mar 24, 2012 7:41 pm

I have enough pieces here to piece one complete pump assembly together, plus some pod bolts and possibly even an extra pushrod or 2.
I have the one assembly that I got from Hansen01 that snapped the shaft, plus one that got obliterated by ball bearings, which still as a good shaft.

If they weren't SUCH a mother to press apart and back together............:roll:

Mark.
Mark Nixon
 
Top

Re: Vacuum Pump Problem

Postby cmann250 » Sun Mar 25, 2012 6:14 am

Thanks Mark, but I think I'm ok and nothing is damaged that bad. I do know where to look if it turns out worse than I think it is :)
Caleb, Certified Shade Tree Mechanic Extraordinaire :mrgreen:
The 1stgen.org black sheep

"Whatever!" - Coach Jerry Smith
cmann250
14mm rotor
 
Posts: 4059
Joined: Fri May 20, 2011 5:25 pm
Location: Lafayette, IN
Top

Re: Vacuum Pump Problem

Postby cmann250 » Wed Mar 28, 2012 2:02 pm

I ordered that little push rod today and it was about $40 :shock:

I don't think I can get that bottom pod back on without removing the whole assembly from the truck. Is there any tips or hints that I should be aware of when I'm taking this deal out?
Caleb, Certified Shade Tree Mechanic Extraordinaire :mrgreen:
The 1stgen.org black sheep

"Whatever!" - Coach Jerry Smith
cmann250
14mm rotor
 
Posts: 4059
Joined: Fri May 20, 2011 5:25 pm
Location: Lafayette, IN
Top

Re: Vacuum Pump Problem

Postby Mark Nixon » Wed Mar 28, 2012 2:31 pm

Cuss like a sailor when you remove the pump lines. :lol:
BEST way would be to remove them from the PUMP, not the steering gear.
The bottom bolt can be a mother to access, too. :roll:

Why didn't you ask me for the pushrod? I would have sent it to you for nothing. :?

Mark.
Mark Nixon
 
Top

Re: Vacuum Pump Problem

Postby cmann250 » Wed Mar 28, 2012 7:11 pm

Mark Nixon wrote:Why didn't you ask me for the pushrod? I would have sent it to you for nothing. :?

Well I should have... I didn't think you'd want to tear apart a rebuildable pump just for that push rod :bh:
Caleb, Certified Shade Tree Mechanic Extraordinaire :mrgreen:
The 1stgen.org black sheep

"Whatever!" - Coach Jerry Smith
cmann250
14mm rotor
 
Posts: 4059
Joined: Fri May 20, 2011 5:25 pm
Location: Lafayette, IN
Top

Re: Vacuum Pump Problem

Postby Mark Nixon » Wed Mar 28, 2012 7:27 pm

I did mention that I possibly had some, which I do:
Mark Nixon wrote:....I have enough pieces here to piece one complete pump assembly together, plus some pod bolts and possibly even an extra pushrod or 2.....

Mark.


No harm, no foul, I would gladly have saved you the money, though. :D

Mark.
Mark Nixon
 
Top

Re: Vacuum Pump Problem

Postby Greenleaf » Thu Mar 29, 2012 4:11 am

cmann250 wrote:I ordered that little push rod today and it was about $40 :shock:

I don't think I can get that bottom pod back on without removing the whole assembly from the truck. Is there any tips or hints that I should be aware of when I'm taking this deal out?


I had to rebuild mine due to the worm bearing noise. You can hear the bad bearing, but if you don't know what to listen for, you'll drive it till it breaks or spend the $ and time to ensure reliability. I also replaced the PS pump while I had it off. Why not.........it too will fail soon enough.

What you'll need to be aware of it this; that big ball bearing spits out the balls when they wear. The balls fall down into the timing gears. :shock: Did you get that? Need a picture of what the damage will be like? Mine had lost the cage. It was gone. That cage holds the balls in alignment.

If I recall,it was like 600.00 for the rebuild;

Power steering lines and hoses etc.
Power steering pump
2-vacuum pods reman from NAPA
that BIG ball bearing
2-push rods
2-push rod guides
Seals/gasket/O rings etc.
Synthetic P.S. fluid

A friend of mine made me a rebuild manual. It was sweet. Had all the part numbers, method of R&R the bearing and pump shaft and the size of the jack screw(s) required to make a home built puller assy to do the job. If I hadn't had that, It would have been more leg work to locate all this stuff and figure out how to take it apart w/o breaking things.
1990/1992 D250 Ram Diesels Modified by *Smokehouse Diesel* Ashland, Ohio ( )==='==~

Don't have such an open mind that all your brains spilleth out.
Greenleaf
tech specialist/mod
 
Posts: 306
Joined: Tue Jan 02, 2007 3:36 am
Location: North Central Ohio
Top

Re: Vacuum Pump Problem

Postby cmann250 » Thu Mar 29, 2012 5:15 am

Thanks for the heads up! I'll give it a close look when I get it out
Caleb, Certified Shade Tree Mechanic Extraordinaire :mrgreen:
The 1stgen.org black sheep

"Whatever!" - Coach Jerry Smith
cmann250
14mm rotor
 
Posts: 4059
Joined: Fri May 20, 2011 5:25 pm
Location: Lafayette, IN
Top

Re: Vacuum Pump Problem

Postby Farmboy92_2009 » Thu Mar 29, 2012 11:10 am

i remember my shop having to rebuild mine 3 times before getting it not to leak...something about the kits i was getting didnt set right, well because the pump itself was morre out enough an new seal wouldnt fit right i guess. well i had em install 1 more rebuild kit for everything and it worked otherwise ida had to buy a whole new pump :/
Farmboy92_2009
fuel screw!!!!
 
Posts: 208
Joined: Sun Mar 25, 2012 10:26 pm
Location: Western, Il
Top

Re: Vacuum Pump Problem

Postby Mark Nixon » Thu Mar 29, 2012 11:31 am

These pumps are marginal, at best.
Greenleaf's example is one that I have seen firsthand.
Ball bearings in the geartrain are very destructive, and it's not pretty at all.
The one I had actually broke the cam. :shock:

It's to the point that a few people have actually converted the non-intercooled engine's pump set-up to the version used on '91-1/2 through '02, mainly because of the cost and lack of parts availability for the early ones.
They are a far superior set-up, pressure lubed instead of splash and just about anyone can rebuild them in their garage, or on a tailgate, in my case. :lol:

Mark.
Mark Nixon
 
Top

Re: Vacuum Pump Problem

Postby cmann250 » Thu Mar 29, 2012 3:53 pm

Mr. Nixon, you have a PM
Caleb, Certified Shade Tree Mechanic Extraordinaire :mrgreen:
The 1stgen.org black sheep

"Whatever!" - Coach Jerry Smith
cmann250
14mm rotor
 
Posts: 4059
Joined: Fri May 20, 2011 5:25 pm
Location: Lafayette, IN
Top


Return to Engine

Who is online

Users browsing this forum: No registered users and 65 guests