HP D-30 vaccuum prob???

Boonie Buster · Jul 23, 2007

I'm not sure exactly what the prob is, havent really tore into it yet though. But when i put it in 4wd and switched the vaccuum hose to the 4wd side, it wouldn't engage in 4wd, but when i pulled the cover off and checked it, the vaccuum would pull back and forth fine, maybe not a strong enough pull? so i put the vaccuum on the 4wd side and physically engaged the fork in 4wd too, and it workeds, but when i took my t-case out of 4wd to go on the road for a bit then put it back in, i was back to three wheel motion. is it just not enough vaccuum???

KarlVP · Jul 23, 2007

It could be not enough vaccum. Is the shift fork "lubed" enough.

Most folks get away from that problem, but installing a one piece shaft, or making a manual cable shifter and capping off the vacuumn lines.

Boonie Buster · Jul 23, 2007

KarlVP said:
It could be not enough vaccum. Is the shift fork "lubed" enough.

Most folks get away from that problem, but installing a one piece shaft, or making a manual cable shifter and capping off the vacuumn lines.

so, would all i need to do is get a one piece shaft then? or do i need to change anything else, cus i saw one guy on the board selling a one piece and if i could do that it would be awesome, that is if it's jsut as easy as pulling my stuff out and putting that shaft in...

KarlVP · Jul 23, 2007

Boonie Buster said:
so, would all i need to do is get a one piece shaft then? or do i need to change anything else, cus i saw one guy on the board selling a one piece and if i could do that it would be awesome, that is if it's jsut as easy as pulling my stuff out and putting that shaft in...

You could do some searching around, but I know the XJ and YJ folks with the 30's just slide a one piece shaft in there and call it a day.

1 grumpy · Jul 23, 2007

Boonie Buster said:
so, would all i need to do is get a one piece shaft then? or do i need to change anything else, cus i saw one guy on the board selling a one piece and if i could do that it would be awesome, that is if it's jsut as easy as pulling my stuff out and putting that shaft in...

yes that's all you need to do,ofcourse if you dicide too go with the cable like I did with my Jeep you can put it in 4 low and not ingage the cable and have 2low which is really nice...

Boonie Buster · Jul 23, 2007

1 grumpy said:
yes that's all you need to do

that's what i like to hear!:awesomework: thanks

Avanteone · Jul 23, 2007

Boonie Buster said:
that's what i like to hear!:awesomework: thanks

It's not QUITE that simple. You also have to install a new long side (RH side) inner axle seal. The seal /w the vac. disco shaft is just outboard of the vac. servo. When you go to a 1 piece shaft you have to install a seal in by the carrier, which involves removing both shafts, carrier, etc. in order to install the seal.

J

Boonie Buster · Jul 23, 2007

Avanteone said:
It's not QUITE that simple. You also have to install a new long side (RH side) inner axle seal. The seal /w the vac. disco shaft is just outboard of the vac. servo. When you go to a 1 piece shaft you have to install a seal in by the carrier, which involves removing both shafts, carrier, etc. in order to install the seal.

J

how hard is installing the seal other than tearing it apart to get to it? does it require machining? or is there space for a seal to go?

Avanteone · Jul 23, 2007

Boonie Buster said:
how hard is installing the seal other than tearing it apart to get to it? does it require machining? or is there space for a seal to go?

It's simple. Just pound the seal into the tube, no machining or anything special. You can buy the Yukon kit from Randy's /w the block off plate and the two different axle seals. Depending on what year the housing is it can take one of two seals and they're different than the drivers side and non-disco housings. If it's pre '87 it's a National seal # 471354 (2.062" diameter) and if it's '87+ it's a #471763 (2.0" diameter).

J

Boonie Buster · Jul 24, 2007

Avanteone said:
It's simple. Just pound the seal into the tube, no machining or anything special. You can buy the Yukon kit from Randy's /w the block off plate and the two different axle seals. Depending on what year the housing is it can take one of two seals and they're different than the drivers side and non-disco housings. If it's pre '87 it's a National seal # 471354 (2.062" diameter) and if it's '87+ it's a #471763 (2.0" diameter).

J

so i just push it into the tube from the inside of the carrier towards the outside knuckles? do you have to get the seal form randy's??? i'm going to make my own plate i think.... thanks, this helps a ton.:awesomework:

crash2 · Jul 24, 2007

Avanteone said:
It's not QUITE that simple. You also have to install a new long side (RH side) inner axle seal. The seal /w the vac. disco shaft is just outboard of the vac. servo. When you go to a 1 piece shaft you have to install a seal in by the carrier, which involves removing both shafts, carrier, etc. in order to install the seal.

J

really--we did a one piece shaft (waggy shaft I thought) in a yj and just swapped out the shaft and never had any problems...

Boonie Buster · Jul 24, 2007

crash said:
really--we did a one piece shaft (waggy shaft I thought) in a yj and just swapped out the shaft and never had any problems...

I'm wondering the same cus isn't there a seal towards the vacuum that holds the oil in? i guess i could try and see, when i fill it up if it starts oozing out the end:redneck: besides i need to fix it anyways, it decided to start leaking fairly bad/consistent the other day

Avanteone · Jul 24, 2007

Boonie Buster said:
so i just push it into the tube from the inside of the carrier towards the outside knuckles? do you have to get the seal form randy's??? i'm going to make my own plate i think.... thanks, this helps a ton.:awesomework:

No, you don't have to go to Randy's. You can go to any auto parts store /w the National seal #'s I gave you and get the right one.

J

Boonie Buster · Jul 24, 2007

Avanteone said:
No, you don't have to go to Randy's. You can go to any auto parts store /w the National seal #'s I gave you and get the right one.

J

ok, cool, i'll have to go and do that and hopefully source out a single piece (in the works) axle to replace it with....this is kinda going to suck though have a lockrite and no hubs though

maybe i should spend $1000 on locking hubs for my D30:haha:

NotMatt · Jul 24, 2007

Yup, get the correct seal, a 1 piece shaft and make yourself a block-off plate for the housing and you're golden.

Plenty of people run lockright style lockers up front in their non-disconnect D30's. When you're not in 4wd you shouldn't even notice it other than some clicking from the locker.

Avanteone · Jul 24, 2007

crash said:
really--we did a one piece shaft (waggy shaft I thought) in a yj and just swapped out the shaft and never had any problems...

I've had it work SHORT term. The place on the shaft where the seal rides for the vac. disco shaft isn't machined smooth on a stock shaft, so it will work temporarily and then tear up the seal. At least that's been MY experience. :redneck:

J

Boonie Buster · Jul 24, 2007

Avanteone said:
I've had it work SHORT term. The place on the shaft where the seal rides for the vac. disco shaft isn't machined smooth on a stock shaft, so it will work temporarily and then tear up the seal. At least that's been MY experience. :redneck:

J

ya, maybe i should replace both sort of as a secondary seal incase one breaks.....maybe...... but i think that's the seal that is leaking right now on me:eeek: