a teacher of mines suggested shimming the oil pump relieve to help / increase with oil pressure....and maybe adding an oil cooler.....
i would to know your view on this
never heard of it but supposidly there is some kind of 'secret mod' that people talk about over on quad four forums that is supposed to help, god knows if it really does though. as far as i know pressure really isnt the issue with the LD9 pump but rather the fact that when you get over a certain RPM it begins to cavitate the oil. now... have i ever experienced this and proven it firsthand? no... that is just going by hearsay and rumors from over the years around here. but i do know one hell of a fact... the LD9 blows rod bearings left and right bone stock. you try and up the performance and get more out of the engine with a setup that is sub-standard for even OEM power you've got a real problem.
now sure, there are a handful of people that will say the LD9 pump is the greatest thing since sliced bread and will be fine with regular maintenance. do i agree with them? negative. as far as i am concerned if it isnt good enough for stock it plain flat out
IS NOT GOOD ENOUGH.
personally, i say why bother, the 2.3 swap isnt that hard and you get to ditch 12 pounds off the rotating assembly as well as nearly 40 pounds of dead weight off the bottom of the engine. plus not only do you get the better oil pump out of the deal you also get a windage tray to help keep oil off the crank. and depending on which way you go with the pan situation, more oil volume if you wish.
I feel like taking a tinkle on an ecNOtec...
yeah im going to do the 2.3 swap personally but i was just kinda like "shimming it??" when he told me about it
The "secret" Brad is referring too is when people remove the spring and install a stiffer spring....and buy the melling high flow 2.4 pump. That is what a JBP highflow pump is.....
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
im going with the 2.3 but anyone having any luck with this, just wondering?
Get an oil cooler for the shear volume of oil which helps overall pressure. You'd go from a standard 4 quarts of oil to 6 quarts with the oil cooler if done right.
I'll probably still go with the 2.3 pump but if things continue where it is I'll be relegated to going with the Melling pump which is good too.
Good luck with your project.
Misnblu.com
Newbie member since 1999
Thank you Dave and JBO! 
I say the LD9 factory oil pump is good for 220whp and 124k. To me that is not weak, or whatever you want to call it.
Most rod bearing failures I have seen on a LD9 have been to negelected (running low on oil etc..) Of course everyone always says I never did that, etc...
FU Tuning
oh we believe you john, you're of the handful that have been lucky.
I feel like taking a tinkle on an ecNOtec...
i'm inclined to agree with john. 90% of normal people out there dont know how to maintain their @!#$ cars and only worry about stuff going wrong after it breaks. a lot of things get a bad rep from stupid people. if people knew how to just do regular maintenance, or even just check their oil level every once in a while i think there'd be a lot more high mileage LD9's out there. too late now though, lol.
of course then there are the people like me who self inflict their problems..
i have a lot of things floating around in my head as to the hatred of the LD9 oil pump, that is why i hate it so much LOL.
ive ran plenty of my 60 degree V6's down on oil so low that you could hear the lifters clattering. lazy? yup... but the fact that they did not die begs the question if the LD9 oil pump sucks.
my dad has a 2000z, he built the engine from the ground up and put 100k on it over the years. changed the oil regularly (you know how old car guys can be) and made sure it was not low yet the engine still blew when he got it stuck in a snow drift trying to get out of it last winter. rod bearing failure.
my 97z24, had plenty of oil in it when it spun a rod bearing. granted it had something like 300 drag passes on it and some nitrous ran through it but the same failure remains....
ive known plenty of people that usually keep their oil flawless, still their rod bearings failed. then i know of one guy (even on here, trevor blesh) that ran his really low on oil and street raced the damn thing, never spun a bearing. so i do think there are some exceptions out there but for the most part you hear of LD9's with the same exact issue. you should not have to keep you're engine under a microscope to make it live, im sorry but id rather just have the peace of mind and weight reduction.
I feel like taking a tinkle on an ecNOtec...
Screaming for Mercy!! wrote:I say the LD9 factory oil pump is good for 220whp and 124k. To me that is not weak, or whatever you want to call it.
Most rod bearing failures I have seen on a LD9 have been to negelected (running low on oil etc..) Of course everyone always says I never did that, etc...
I never did that.
Horsepower has nothing to do with the problem with the LD9 pump. The problem is cavitation, like Brad said. I think the real issue, though, is someone needs to look into why it's rod bearing #3 99.9% of the time. Of all the 2.3 vs 2.4 pump arguments, I've never seen this discussed.
I have no signiture
I have a LD9 with over 200k on it and as far as i know its the original oil pump.
If you do the 2.3 conversion with the factory 2.3 pickup and pan modification you end up with about 7 quarts in your oil pan.
the 2.4 pump is tiny and spins roughly twice engine speed (from what I recall) where as the 2.3 pump spins slightly faster than engine speed.
The motor in my car is approaching 180k miles. Never been opened up, I pulled the motor from a wrecked, riced out grand am from the junk yard with 80k miles. Motor had very little oil in it when I got it. I was in a pinch and needed one to go to work.
I check my oil every other week. Gets changed every 8-10 weeks and I only run castrol gtx or mobile 1 in it, always 10w30.
I've been lucky to never have any issues (knock on wood).
The motor I pulled out had like 60k miles, and always had royal purple oil ran in it. It was pulled due to a noise in the motor that I assumed at the time was rod knock. Have yet to open the motor to find out.
The motor is sitting on an engine stand with 6 year old royal purple in it. The motor will be torn down and completely cleaned before using again though.
I think its kinda hit or miss with the oil pumps in these motors. Maybe somewhere along the line of making them they had manufacturing issues that no one ever caught.
All I know is when the motor gets built, it will posess a melling 2.3 pump.
"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"
I think in the near future I will be doing as melling oil pump swap on my 2.4. I have 124k on it, and very hard 124k. I think this would be a good test of the difference in the melling pump and the factory pump, so I will likely be doing this very soon next month or 2.
FU Tuning
Whalesac wrote:Screaming for Mercy!! wrote:I say the LD9 factory oil pump is good for 220whp and 124k. To me that is not weak, or whatever you want to call it.
Most rod bearing failures I have seen on a LD9 have been to negelected (running low on oil etc..) Of course everyone always says I never did that, etc...
I never did that.
Horsepower has nothing to do with the problem with the LD9 pump. The problem is cavitation, like Brad said. I think the real issue, though, is someone needs to look into why it's rod bearing #3 99.9% of the time. Of all the 2.3 vs 2.4 pump arguments, I've never seen this discussed.
That's a good point....... when my ld9 spun a bearing it was the #3 like most
Could be a restriction in the crank... design flaw maybe.... I know the block has the oil flow as we would have problems with #4 and still have problems even after the 2.3 oil pump swap.
Unfortunately i dont have the ability to cross section the crank.
I wonder if i still have the diagram of the 2.4 oil flow.
Well i looked at the diagram and it looks like the center main journal which feeds #3 rod bearing is the FIRST to get oil from the pump. Which could mean that if the oil cavitates its also the FIRST to get the lack of oil therefore causing it to spin.... All speculation but it makes sense in my brain.
#3 is the thrust bearing... or so I've been told. I always kept oil in mine, so I never had an issue... even with 85hp shots of nitrous
who cares about mains anyways? LOL its always the rods that go..
I feel like taking a tinkle on an ecNOtec...
Question this is some what related to this topic. Has anyone used the block for oil pressure reading instead of the head?? Is there a difference between the head reading and the block reading?
FU Tuning
Screaming for Mercy!! wrote:Question this is some what related to this topic. Has anyone used the block for oil pressure reading instead of the head?? Is there a difference between the head reading and the block reading?
One could assume that there would be pressure differences depending on where the measurement is being taken...No evidence from my end unfortunately.
But I can tell you that when my #3 went,
It was sheer neglect. I was being a retard and punched it around a left hand turn while the oil was low. Did not know it was that low, But hey, It's got a new motor now
Top off you oil.
For starters... GM recommends 4 qrts of oil. In reality you will need
4.5 qrts when you do a filter and oil change. So you already start of low. Then those people that didn't do a good "break in" period in its first 500-1000 miles of the engine's life often runs the risk of burning oil quicker than normal. So if you burn oil and you are already low, you're susceptible of some weak point failing later on, in this case, on the LD9 it's the 3rd bearing.
Switching oil pumps... if one is going to go through the effort of changing pumps, do something that is more effective and truly an upgrade; go dry sump. If money is an issue and you're running more that 6600 rpms redline, the 2.3L oil pump may be more effective then the 2.4L pump, as GM had some 2.3L Quads run up to 7400 rpms redline. In other words, engineered from the start.
With all of this said, with all of my years here I don't remember anyone here who went to dry sump for the LD9. But, there have been plenty that went with a 2.3L oil pump, and at least there have been two occasions here where there have been 3rd bearing failure over in the maintenance section. I will always say, if you have a high reving engine go with 2.3L pump, but if you want to prevent a rod failure top oil and check religiously no matter what pump you have. Infact... top off your oil on any engine.
>>>For Sale? Clicky!<<<
-----The orginal Mr.Goodwrench on the JBO since 11/99-----
I personally only ever put about 4.25qts of oil in when I change my oil. I prefer a little low rather than a little over full. don't want too much and cause it it possibly cavitate more.
"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"
