JeepHammer help please. Oil Pump rebuild. - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > JeepHammer help please. Oil Pump rebuild.

Rampage Bowless Soft Top Oconee offroadAlloy USA Still AvailableAdvance Adapters SYE Kits

Reply
Unread 06-10-2010, 09:02 AM   #1
BioTex
Registered User
2006 TJ Wrangler 
 
Join Date: May 2008
Location: Alpine, Tx.
Posts: 3,173
JeepHammer help please. Oil Pump rebuild.

JH,
I have the timing cover off my 360, and will be installing a new oil pump and front seal. I'd love for you to share your expertice on what I need to do to do the job the right way.
I did not order the midplate when I ordered the new pump, but understand now that I should have. The pump will arrive today, so can I install it right away, and add the midplate later, or do I need to do it all at the same time.
Any tips/tricks much appreciated.
Eric

__________________
'85 CJ7, BDS 4" lift, 1" Body lift, 33x12.5, Shrockworks Sliders, 304 V8 with RV cam., T-176, D300, Dana 30, AMC 20.
1986 CJ10-A SD-33 Diesel/727/np208
1971 800B with 345/T-19
06' TJ Rubicon, 4" R.C. springs, BFG/AT 35s M.C. 6" fenders, rockers and surrounds, Currie front & rear adj. tracbars, tattons DC rear shaft, adj. upper - lower CA's. Bilstein 5100's
YJ Buggy Build Current project. Stroker/FI ?
1990 MJ Comanche 4.0L AX15/np231
BioTex is offline   Reply With Quote Quick reply to this message
Unread 06-10-2010, 09:18 AM   #2
JeepHammer
Running On Empty...
1973 CJ5 
 
Join Date: Aug 2007
Location: South West Indiana
Posts: 10,212
I would hold off and add the mid plate in when doing the rebuild that way you only have to do it once.

Take a look at the floor plate/filter head and see if the bottom of the oil pump/floor plate is carved up...
If you have scratches you can hang a fingernail on, it's time for a mid-plate.

I'm getting ready to do one myself, so I can post pictures of the procedure if you like, but it will be a day or two before I get to it.
I have something to do today, tomorrow I have broken bolts and lots of crud to clean up before I can proceed.

You will need a stick or two of PLASTI-Gauge, you can get it at any parts store, but the guys at NAPA will be more likely not to look at you like you are an idiot when you ask for it...

Take a look at this...
LINK: http://www.bjsoffroad.com/CartGenie/prod-605.htm

If the pump you ordered doesn't come with extra gaskets (you will need to adjust thickness for clearance) and the spring/plugner for the bypass,
It's time for a new kit...

LINK: http://www.bjsoffroad.com/CartGenie/prod-417.htm

When you service the plunger, remember to put some sealer on the threads of the bolt holding it together.
I know there is a gasket, but DOUBLE protection from leaks doesn't hurt anything, and it's just a little 'Goo' on the threads that will keep a leak off your nice, clean work!
---------------------------

Remember to drive the static pin (Driven, not driving impeller pin) out with a brass punch,
Use some RED locktite in the hole, put it back in so you don't have oil weeping around that pin since it goes clear though the housing.

That will clean up one of those AMC 'Mystery Leaks' that always seem to plague us!

BE CAREFUL and support the case, don't beat up the pin or case when you take it out or put it back in!

Last edited by JeepHammer; 06-10-2010 at 09:38 AM..
JeepHammer is offline   Reply With Quote Quick reply to this message
Unread 06-10-2010, 09:46 AM   #3
BioTex
Registered User
2006 TJ Wrangler 
 
Join Date: May 2008
Location: Alpine, Tx.
Posts: 3,173
Quote:
Originally Posted by JeepHammer View Post
I would hold off and add the mid plate in when doing the rebuild that way you only have to do it once.

Take a look at the floor plate/filter head and see if the bottom of the oil pump/floor plate is carved up...
If you have scratches you can hang a fingernail on, it's time for a mid-plate.

I'm getting ready to do one myself, so I can post pictures of the procedure if you like, but it will be a day or two before I get to it.
I have something to do today, tomorrow I have broken bolts and lots of crud to clean up before I can proceed.

You will need a stick or two of PLASTI-Gauge, you can get it at any parts store, but the guys at NAPA will be more likely not to look at you like you are an idiot when you ask for it...

Take a look at this...
LINK: View the Oil Pump Midplate at http://www.bjsoffroad.com

If the pump you ordered doesn't come with extra gaskets (you will need to adjust thickness for clearance) and the spring/plugner for the bypass,
It's time for a new kit...

LINK: View the AMC V8 Oil Pump Repair Kit at http://www.bjsoffroad.com

When you service the plunger, remember to put some sealer on the threads of the bolt holding it together.
I know there is a gasket, but DOUBLE protection from leaks doesn't hurt anything, and it's just a little 'Goo' on the threads that will keep a leak off your nice, clean work!
---------------------------

Remember to drive the static pin (Driven, not driving impeller pin) out with a brass punch,
Use some RED locktite in the hole, put it back in so you don't have oil weeping around that pin since it goes clear though the housing.

That will clean up one of those AMC 'Mystery Leaks' that always seem to plague us!

BE CAREFUL and support the case, don't beat up the pin or case when you take it out or put it back in!
I have plastigauge in my toolbox. What is the clearances I want?

I have BJ's oil pump set. I will order the midplate if needed.

Pictures would be nice.

Also, since I had three stripped out 1/4" x 20 bolt hole in the cover, and one broken off, I bought replacement studs. I chased the threads, and am planning on using the studs with some locktite. Do you have any problem with this, or should i helicoil.
I really don't want to helicoil unless there is no other option.
__________________
'85 CJ7, BDS 4" lift, 1" Body lift, 33x12.5, Shrockworks Sliders, 304 V8 with RV cam., T-176, D300, Dana 30, AMC 20.
1986 CJ10-A SD-33 Diesel/727/np208
1971 800B with 345/T-19
06' TJ Rubicon, 4" R.C. springs, BFG/AT 35s M.C. 6" fenders, rockers and surrounds, Currie front & rear adj. tracbars, tattons DC rear shaft, adj. upper - lower CA's. Bilstein 5100's
YJ Buggy Build Current project. Stroker/FI ?
1990 MJ Comanche 4.0L AX15/np231
BioTex is offline   Reply With Quote Quick reply to this message
Unread 06-10-2010, 10:20 AM   #4
JeepHammer
Running On Empty...
1973 CJ5 
 
Join Date: Aug 2007
Location: South West Indiana
Posts: 10,212
Quote:
Originally Posted by BioTex View Post
I have plastigauge in my toolbox. What is the clearances I want?

I have BJ's oil pump set. I will order the midplate if needed.

Pictures would be nice.

Also, since I had three stripped out 1/4" x 20 bolt hole in the cover, and one broken off, I bought replacement studs. I chased the threads, and am planning on using the studs with some locktite. Do you have any problem with this, or should i helicoil.
I really don't want to helicoil unless there is no other option.
I don't like to heli-coil something that thin in CAST Aluminum unless I have no other choice.
I'd rather use the stock threads and some studs like you are planning.


--------------------------------------------

The pump specs are (Depending On Manual You Have...)

1. Feeler Gauge, Impeller 'Gear' end to case, 0.0005" to 0.0025"


Different makers will have different tolerances, so if the impeller 'Gears' don't fit the case, try a different manufacturer.
-----------------------------------------

2. Impeller to case bottom (With gasket in place),
0.002 to 0.006"
, use plasti-gauge for this, there is no other way to tell how much the gasket is compressing.

I run the plasti-guage pretty much all across the impellers so I can see if it's even, or there is something warped or the gears are machined stupid.
(Melling make some STUPID mistakes sometimes!)
------------------------------------------

3. Oil pressure relief valve shouldn't get more than 75 PSI no matter how cold/thick the oil is or you risk blowing the filter apart.
I usually shim mine for around 60-65 PSI just to be safe.
-------------------------------------------

Bolts are CRITICAL since they determine how much crush the gasket is going to get...

4. You are looking at 4.5 Ft.Lbs, (54 INCH Pounds)
And that's for USS threads.

SAE or 'Fine' thereads on studs will be more clamping power than 'Course' threads for the same torque, but that's not an issue as long as you torque back down the same each time.

If you need different thickness gaskets, try 'Manila' file folders.
Any kind of compressed paper will make a gasket for this just fine,
And it's TEDIOUS, but if your pump doesn't come with different thickness of gaskets (and many don't) you will need to make one that closes up the gap to get oil pressure correctly.

Just trace out, then cut out from the gasket that came with the pump and try something you made.
You don't know how much time I spend cutting out gaskets for engines like this to get the correct 'Tight' tolerances!
It's SLOW & Tedious, but you probably won't have to do it again for this engine for many years to come!

One last foot note,
5. Make sure the relief valve slides freely in it's bore!
If it sticks, you can blow the filter open when it hangs up at the wrong time.
JeepHammer is offline   Reply With Quote Quick reply to this message
Unread 06-10-2010, 10:26 AM   #5
twmattox
Registered User
 
Join Date: Mar 2002
Location: Indianapolis
Posts: 1,290
Ummm...I would wait to put it together until you have the midplate. They are a worthwhile addition to the build.

I would also recommend getting a decent sized piece of flat glass, some valve lapping compound, and some plastigauge. Then follow this (it is from a different forum):

V8 timing cover/Oil pump refresher. pic heavy. - International Full Size Jeep Association
twmattox is offline   Reply With Quote Quick reply to this message
Unread 06-10-2010, 10:39 AM   #6
JeepHammer
Running On Empty...
1973 CJ5 
 
Join Date: Aug 2007
Location: South West Indiana
Posts: 10,212
Midplate negates the need for lapping the filter head/floor plate to the pump,
Comes flat and true, or it's supposed to, the ones from BullTear sometimes need work to make them flat...

Lapping the housing closes up the tolerances for the pump impellers.
You can do this once or twice, but after that your front cover is junk because you don't have enough clearance for the gears to floor plate...

We lap the race cars, but I don't bother with the common Jeeps other than to square up the bottom of the housing (Impeller side). I don't want remove any more material than I have to...
I might want to rebuild this engine/front cover again sometime!

If you are going to use a sheet of glass,
Get a piece of HEAVY plate glass, set it in a wet sand bed to keep it from flexing in the middle.

Car window glass is tempered and too thin, and will flex like crazy.

I use a lapping stone, a machined, trued stone designed specifically for this sort of thing.
Good for things like water necks too...
--------------------------------------------------

And the comment about plugging up the bypass...
Your engine getting 'Dirty' oil...

The idea of the bypass is when the filter gets plugged up, the oil is allowed to circuilate bypassing the filter.
Dirty oil is better than no oil at all, which is what you get when you plug the bypass!

Some of the better filters have a bypass built into them, but other brands still do not have a bypass, and if the paper material decides to fragment and plug the filter, you are SCREWED with a plugged bypass!

The bypass also protects the filter from overpressure,
Like when you start up on cold morning with a crankcase of molasses and the oil pressure shoots way up...
The bypass lets it go around the filter until the oil gets thin enough to pass through the filter correctly...

Again, even 'Dirty' oil is better than NO OIL!
I'll keep my bypass, thank you very much!
I would rather it 'Failed Safe' than failed and wiped out the engine!

------------------------------------------

Having said that, you do it any way you want to, there are a LOT of opinions about everything out there, and you should shop around and see what you think will work for you...

Last edited by JeepHammer; 06-10-2010 at 10:50 AM..
JeepHammer is offline   Reply With Quote Quick reply to this message
Unread 06-10-2010, 11:06 AM   #7
twmattox
Registered User
 
Join Date: Mar 2002
Location: Indianapolis
Posts: 1,290
I thought it odd that on my 360 (came from an '88 GW) the bypass was cast shut (apparently from the factory). After reading about it (I know...don't believe everything you read), Chrysler began casting them shut because they failed open very frequently. So, I started looking at oil filters more closely...just to make sure that I was not buying one that did not have an internal bypass. So far, all of them I have looked at contain an internal bypass (makes me feel better). All three versions of the Fram, the STP I like, the Purolator, and the Wix all had internal bypasses (those are the only ones I checked).

As far as lapping the main housing, I did it to mine. But, that was because I found that the gears had eaten into the back of that housing (similar to how they had eaten into the filter head/floor plate to the pump. So, I lapped a bit off to return the item to spec. Not sure if that is normal, if it had high mileage, or what...but if I didn't lap it, I would not have been to spec (even bolting it together without a gasket).

Regardless, after the rebuild on mine, I am getting 50ish on a cold start, and after warmed up 30ish cruising down the highway, and 10ish at idle. I would feel a whole lot better if it were like my wife's new Grand Cherokee (a constant 40 all the time), but from what I have read in the owners manual, I am right where I am suppose to be.
twmattox is offline   Reply With Quote Quick reply to this message
Unread 06-10-2010, 08:30 PM   #8
JeepHammer
Running On Empty...
1973 CJ5 
 
Join Date: Aug 2007
Location: South West Indiana
Posts: 10,212
Quote:
Originally Posted by twmattox View Post
I thought it odd that on my 360 (came from an '88 GW) the bypass was cast shut (apparently from the factory). After reading about it (I know...don't believe everything you read), Chrysler began casting them shut because they failed open very frequently. So, I started looking at oil filters more closely...just to make sure that I was not buying one that did not have an internal bypass. So far, all of them I have looked at contain an internal bypass (makes me feel better). All three versions of the Fram, the STP I like, the Purolator, and the Wix all had internal bypasses (those are the only ones I checked).

As far as lapping the main housing, I did it to mine. But, that was because I found that the gears had eaten into the back of that housing (similar to how they had eaten into the filter head/floor plate to the pump. So, I lapped a bit off to return the item to spec. Not sure if that is normal, if it had high mileage, or what...but if I didn't lap it, I would not have been to spec (even bolting it together without a gasket).

Regardless, after the rebuild on mine, I am getting 50ish on a cold start, and after warmed up 30ish cruising down the highway, and 10ish at idle. I would feel a whole lot better if it were like my wife's new Grand Cherokee (a constant 40 all the time), but from what I have read in the owners manual, I am right where I am suppose to be.
There is a way to keep the pump impellers (Gears) from eating their way up.
They move up because there is oil pressure trying to get under them, then they 'Zig Zag', one up, one down, then they change position letting off pressure one side then the other.

If you cut a little groove in the floor plate between the shafts, where the impellers meet and there is zero pressure, it will allow the gears to equalize without alternating lift/drop and they won't try to eat their way out.

That allows you to close the tolerances up considerably and raise oil pressure.
JeepHammer is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.