Stud Girdle Kit and Oil Pump Questions (98+ pumps)

[john8662]

As some have read in the post "lower oil pressure than normal, things I can check" post, I have been troubleshooting a lower than normal pressure reading on my 1995 K2500 Suburban 6.5TD HO.

I got the oil pan off the engine finally by unbolting the front differential and getting the clearance I needed. The mechanics I talked to said the only way to get the pan off was to pull the engine, the heck with that (suburban owners understand). Anyways, I took the pan off to replace the oil pump as its the last thing to try. I did find one possible problem for the oil pressure, but I think that it lead to the lower pressure output by the oil pump. I found that one of the copper o-rings supplied with the Lube Specialist oil cooler lines had slipped during my installation and was half way blocking the line going to the cooler. This had been this way for about 4k miles before I suddenly got lower pressure. I have elected to leave them out, it won't leak w/o them. Anyways.. It might have messed up something else, as I removed the rings and got the same pressure.

On a good note, while I have the pan off I stumled upon something good, the block is completly crack free (main webs). So, I got to thinking "since I am here" I am considering installing a Stud Girdle kit from DSG. So my questions for that are, who has done this with the engine in the vehicle? Is there instructions with the kit (torque specs, etc)? Do you have to take the inner main cap bolts out and re-torque when doing this or just the outer bolts on the caps? I am just considering this as the engine is crack free for now with 105k miles on it.

The next question comes from those who have installed the 98+ oil pump in the "599" cast blocks from 91-96 6.2 - 6.5TD. In my last post about oil pressure "david" mentioned that he installed the 98+ oil pump and oil pump pick-up into his 96 non oil spray piston engine. He reported higher oil pressure. I was wondering if anyone else had done this and if this is a good idea or not. I already ordered the pump for a 98+ it just hasn't come in yet (amazing how only the dealer can get an oil pump for a 6.5TD). If its a good idea, then I'll go for it, otherwise I might send it back and get the one for the 95.

By the way, what does one look for when taking an oil pump apart as far as wear, I can't see anything inside of my oil pump that really looks bad, but maybee its bypass valve is bad?

For pics of what I'm talking about with the oil pump wear, go here:

http://members.cox.net/acmdsl/oilpump/

Thanks for reading, and your comments!

[ 05-23-2004, 09:43 PM: Message edited by: john8662 ]

[Bruce Ostien]

John, I can't comment on the oil pump questions but I just did the Stud Girdle on my 99' 4x4 suburban. Got my oil pan off the same way you did yours. Only the outer cap bolts have to come out. The holes are drilled to fit the stud's tight but everything was machined perfectly (slid right into place). Instructions include torque specs. Hard to prove whether the girdle kits work or not but I'll take the additional insurance.

[Bruce Ostien]

Oh yeah, Installed oil cooler lines at the same time and noticed that the copper washers like to move around when installing the fitting at an angle. I super glued the copper washers into place on the fittings to guarntee that they located correctly. Used a very small amount in one place not all the way around, just enough to hold them in-place until the beveled surfaces meet.

[MTTwister]

John - I don't have the spec's, but when researching an oil pump problem on a 350 chevy, there were feeler guage measurements between the gears and housing, and housing to cover that were critical. A little too much clearance can evidently reduce 'efficiency' quite rapidly. In theory, this would apply to any oil pump... As long as you have it out... swap it out? Good Luck.

[john8662]

Bruce Ostien,

thanks for the reply about the stud kit. I wanted to have a responce from someone that did the upgrade in the vehicle, and had good luck with it. I'll order the kit, hopeing it will arrive this week, for a weekend of fun to come.

On another note, went to the dealer and picked up my new oil pump, it came with the new oil pickup tube/screen. I almost had to buy one, till I opened the box on the counter, and saw I already had one. I have compared the two pumps, wow, the 98+ pump is A LOT bigger. Its mine whether I want it or not now, special order at the dealer. Any comments on good verses bad with this preticular pump installed in a 95 block? Thanks!

[ 05-24-2004, 02:29 PM: Message edited by: john8662 ]

[JoeyD]

It is possible that the pressure could be to high, esp. in the morning when oil is cold and thick.
You have it so maybe just install it and run it with it and see. Don't install the diff just incase. If no one has done it you may have to do it for others to learn.

[Dezman125]

Hi
I put a girdle kit on my 90 6.2.It was a easy install. I took a wire wheel to the girdle's,to cleen the powdercoat off.I didn't like the idea of powdercoat on the surfaces that were in contact and under tourqe.Their was a few others that had the same concerns.Thought i would pass it on.

[john8662]

Stud girdle kit installed, I didn't grind off the powder coat, didn't think it would hurt that bad. The 98+ oil pump didn't really make MORE oil pressure, it delivers more volume. The pump makes 60psi oil pressure cold (well 90 degrees outside first start) at idle. On the highway it runs 60psi as well. When up to full operating temperature it runs 55psi at 2k rpm and 35psi at idle. These readings with a mechanical guage, that match the inside the guage. I like the new oil pump. All in all, after all my work, I am glad that it was the oil pump, because I wasn't looking forward to tearing it down again.

John

[tom.mcinerney]

Just to corroborate -- as MTTwister reports, the things to check on gear-type oilpumps are
1.) gear backlash, preferably with tapered (thin) feeler gages [must be thinner than gearteeth are wide, or don't fit].
2.) visually, is there a lot of wear in the circular grooves on housing/cover?[not on John's].
3.) clearance between gear and cover (feeler gage again).

I think i've seen blued heat marks on oil pump gears. I always thought it was from initial manufacturing heat treatmemt of the gears (they require hardness). ???

While on the subject, the valley/channel/groove in the housing that extends toward centerline between gears (allowing oil to flow into region between gearteeth from top/bottom as well as side)
should not have a sharp edge; i think i recall discussion of radiusing the edges....
P.S. I've never had the right thickness gage to check these.

I believe John has proved a failure mechanism exists in the lube system on these trucks; either the bypass or the pump....THANKS, John!

[JeepSJ]

I just installed my main girdle and it was very easy to install. I also removed the powder coating.

Something that hasn't been discussed about the ARP studs that are included with the kit... ARP recommends that all of their fasteners go through 3 torque cycles before final assembly. All fasteners will stretch slightly when torqued and will not return all the way to the original length. ARP says that torquing their fasteners 3 times will set the fastener to the final length and you will get a better clamping load. So, install and torque the nuts, loosen and torque again, and loosen and torque one final time.

This topic is discussed in detail on the ARP website.

[john8662]

I torqued mine twice, mainly because when I had everything fully installed I noticed that one of the studs didn't look like it went in all the way (looked longer than the rest). So I took it back apart, pulled that bearing cap, because it was cauing the stud to not go in all the way easily. Put the bearing cap back in (put assembly lube on the bearing). Then put it all back together, that time it went in perfect.