Oil pump failed
08-25-2009, 12:25 PM
#16
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Year: 1996 & 2001
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Engine: 4.0
I believe your engine will probably last a wile. You can pickup a good engine out a jeep that been wreck in rear low miles for $400 to 600. I just replaced engine in 2001 Jeep Cherokee Sport. Engine in Cherokee are easy to change out.
08-25-2009, 05:38 PM
#18
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Year: 1998
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Ok, got the truck started, oil pressurre up to about 60 psi now. Still have a noise on the top end like Richxj, but don't really hear it much under the unit. Hopefully we dodged a bullet, time will tell, Sounds now like one or two lifters havent pumped up. How hard to change out lifters? Another prob, oil pan leaking around three bolts right in front of the starter. Amazingly I used my considerable strength to strip those three bolts,one after the other, you'd think Id learn, anyone got an idea how to fix that? oil oozing from around the bolts.
08-25-2009, 10:01 PM
#19
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I used the ..
HV. Bunch of pressure ... judging by the pump housing, the pump drive gears are probably half again as big as the standard pump. It's a good 'un. 
08-25-2009, 10:23 PM
#20
High volume pumps do not increase the oil pressure, stricktly the volume.
Stick with a standard volume pump. Had one in my stoker and suspect it was the cause of a cam failure (#6 exhaust lobe).
Stick with a standard volume pump. Had one in my stoker and suspect it was the cause of a cam failure (#6 exhaust lobe).
08-26-2009, 06:11 AM
#21
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FrankZ
Well .... frankly speaking, I beg to differ. In 40 years of using these pumps on everything, stock or otherwise, that I have ever rebuilt I have always seen increased pressure. Since there is a greater volume attempting to be forced through the same size restrictions (crank, cam , wristpin and rod journals, etc.), the pressure is increased as well 
. Did your oil pressure guage not read higher once you installed the pump?
Seems unlikey to me that an HV oil pump would cause a camshaft failure unless it pumped all the oil out of the pan somehow ... possibly low to begin with AND/OR while operating at an extreme attitude, which would be a whole different set of circumstances ... more likely that a lifter was bad or worn, OR the cam had a weak or worn lobe initially OR a cam bearing was worn OR if the cam bearings were new with the stroker ... likely damaged during installation or misalligned ... happens.
. Did your oil pressure guage not read higher once you installed the pump? Seems unlikey to me that an HV oil pump would cause a camshaft failure unless it pumped all the oil out of the pan somehow ... possibly low to begin with AND/OR while operating at an extreme attitude, which would be a whole different set of circumstances ... more likely that a lifter was bad or worn, OR the cam had a weak or worn lobe initially OR a cam bearing was worn OR if the cam bearings were new with the stroker ... likely damaged during installation or misalligned ... happens.
08-26-2009, 07:27 AM
#22
Well .... frankly speaking, I beg to differ. In 40 years of using these pumps on everything, stock or otherwise, that I have ever rebuilt I have always seen increased pressure. Since there is a greater volume attempting to be forced through the same size restrictions (crank, cam , wristpin and rod journals, etc.), the pressure is increased as well . Did your oil pressure guage not read higher once you installed the pump?
Seems unlikey to me that an HV oil pump would cause a camshaft failure unless it pumped all the oil out of the pan somehow ... possibly low to begin with AND/OR while operating at an extreme attitude, which would be a whole different set of circumstances ... more likely that a lifter was bad or worn, OR the cam had a weak or worn lobe initially OR a cam bearing was worn OR if the cam bearings were new with the stroker ... likely damaged during installation or misalligned ... happens.
. Did your oil pressure guage not read higher once you installed the pump? Seems unlikey to me that an HV oil pump would cause a camshaft failure unless it pumped all the oil out of the pan somehow ... possibly low to begin with AND/OR while operating at an extreme attitude, which would be a whole different set of circumstances ... more likely that a lifter was bad or worn, OR the cam had a weak or worn lobe initially OR a cam bearing was worn OR if the cam bearings were new with the stroker ... likely damaged during installation or misalligned ... happens.
http://www.youtube.com/watch?v=7IpJl..._embedded#t=15
My cam failure was just one of many that have happened on not only stroked Jeep engines, but on a huge variety of engines nation wide. Trust me when I tell you that all other possible causes were eliminated.
08-28-2009, 07:20 AM
#25
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Just fired of an email to Melling ...
Yes, I do understand that valving controls the pressure and I saw the video. Be interesting to see what Melling has to say regarding the cam failures.
Sorry for being such a pragmatist also .... I'm just not much for rumor or innuendo, thank you, but if there is something new to learn here, I DEFFINATELY want to learn it to.
My HV pumps, and I have used dozens of them over a lifetime of rebuilds and builds have always worked perfectly. I recently put one in my 4.0 HO at roughly 260K while replacing a bent pan and then immediately drove it across the US pulling a trailer with a large road bike on it.
I have observed several times, but never experienced personally, several failures that have resulted from pumps not being properly primed though. So go figure? ... will be interesting to see if Melling responds and what they have to say.
Sorry for being such a pragmatist also .... I'm just not much for rumor or innuendo, thank you, but if there is something new to learn here, I DEFFINATELY want to learn it to.
My HV pumps, and I have used dozens of them over a lifetime of rebuilds and builds have always worked perfectly. I recently put one in my 4.0 HO at roughly 260K while replacing a bent pan and then immediately drove it across the US pulling a trailer with a large road bike on it.
I have observed several times, but never experienced personally, several failures that have resulted from pumps not being properly primed though. So go figure? ... will be interesting to see if Melling responds and what they have to say.
08-28-2009, 08:36 AM
#26
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"And now, the rest of the story", The late PH would have said ...
Almost before I could cook a couple toaster waffles, George Richmond from Melling responded to my question. Below you will find both my letter to him, his response and links to ALL THREE Melling OP videos on YouTube.
Bottom line is: if you believe that an HV/HP OP trashed your motor, you probably also believe in Voodoo and the Tooth Fairy too, no offense.
Sir:
Please see the videos on www.melling.com and listen carefully.
BS on the cam lobe.
George Richmond
Technical Services Manager
ASE Master Automotive Technician
Melling Tool Company
2620 Saradan Drive
Jackson, MI 49202
517-787-8172 Ext 134
Name:
Steve Dieter
Email:
Department2:
Technical
Subject:
HV oil pumps
Message:
I have a friend who claims that the installation of a new HV oil pump does not incresse oil pressure, yet since I used these pumps exclusively for over 40 years, I always note a higher reading on the guage. Can you explain why this is, please. I have seen the video on youtube showing the example of how flow changes with bearing clearance. I also understand that there is valving in the pump.
This same friend claims that his Jeep stroker motor lost a cam lobe as a result of using a Melling HV pump, to which I promptly called BS. I put one in my own Jeep HO with 260 K on it roughly 5K miles ago, drove it across the USA pulling a trailer. Perfedt ... according to the guage, it has much greater pressure than before. Thank you.
Steve
Bottom line is: if you believe that an HV/HP OP trashed your motor, you probably also believe in Voodoo and the Tooth Fairy too, no offense.
Sir:
Please see the videos on www.melling.com and listen carefully.
BS on the cam lobe.
George Richmond
Technical Services Manager
ASE Master Automotive Technician
Melling Tool Company
2620 Saradan Drive
Jackson, MI 49202
517-787-8172 Ext 134
Name:
Steve Dieter
Email:
Department2:
Technical
Subject:
HV oil pumps
Message:
I have a friend who claims that the installation of a new HV oil pump does not incresse oil pressure, yet since I used these pumps exclusively for over 40 years, I always note a higher reading on the guage. Can you explain why this is, please. I have seen the video on youtube showing the example of how flow changes with bearing clearance. I also understand that there is valving in the pump.
This same friend claims that his Jeep stroker motor lost a cam lobe as a result of using a Melling HV pump, to which I promptly called BS. I put one in my own Jeep HO with 260 K on it roughly 5K miles ago, drove it across the USA pulling a trailer. Perfedt ... according to the guage, it has much greater pressure than before. Thank you.
Steve
lol.
08-28-2009, 09:16 AM
#28
Bear with me on this one.
The engine was machined by a local shop that specializes in racing motors almost exclusively. Damn near had to beg to get them to do it. All of the bearings were new Clevite77. Every bearing was checked with plasitigage prior to assembly and all were perfect. The block was hot tanked before and after machining and I also cleaned every oil passage out to ensure zero oil delivery issues. The cam was installed per the manufacturers instructions and copious amounts of cam assembly grease was used as well as Permatex assembly lube on every moving part. All lifters were measured as were the lifter bores. The motor was broke-in properly and nothing but high ZDDP oil was used.
Not only did the #6 lobe fail, but the #1 was showing signs of unusual wear as well.
Here's what the Cam and lifter looked like.
Notice the severe wear on the lifter? See the hole in the lifter face?
After much research, including pestering the snot out of multiple local and out of state shops the consensus was that pump was the culprit. The theory is that the oil (like water was following the path of least resistance and this means a greater volume of oil was delivered to the ports nearest the pump with the oil passages ad the extreme ends of the block receiving less oil. The #2- thru #5 cam lobes and lifters were perfect.
No obstructions of any kind were found when the engine was disassembled, and that includes anything in the oil that was drained from the engine and the nothing was in the filter either. Yes the I cut the filter open.
So I understand your position on the failure, and yes of course Melling is going to say "B.S." but I'm not the only person to ever experience a cam failure of this type. JP Magazine's stroker did the same thing.
So you can believe what you want, but you weren't there and you didn't spend the time on the engine, nor did you exhaust all other possible causes. So please be a decent lad and accept the fact that your opinion is nothing more than that, an opinion.
Back to the original thread, sorry for the hijack.
The engine was machined by a local shop that specializes in racing motors almost exclusively. Damn near had to beg to get them to do it. All of the bearings were new Clevite77. Every bearing was checked with plasitigage prior to assembly and all were perfect. The block was hot tanked before and after machining and I also cleaned every oil passage out to ensure zero oil delivery issues. The cam was installed per the manufacturers instructions and copious amounts of cam assembly grease was used as well as Permatex assembly lube on every moving part. All lifters were measured as were the lifter bores. The motor was broke-in properly and nothing but high ZDDP oil was used.
Not only did the #6 lobe fail, but the #1 was showing signs of unusual wear as well.
Here's what the Cam and lifter looked like.
Notice the severe wear on the lifter? See the hole in the lifter face?
After much research, including pestering the snot out of multiple local and out of state shops the consensus was that pump was the culprit. The theory is that the oil (like water was following the path of least resistance and this means a greater volume of oil was delivered to the ports nearest the pump with the oil passages ad the extreme ends of the block receiving less oil. The #2- thru #5 cam lobes and lifters were perfect.
No obstructions of any kind were found when the engine was disassembled, and that includes anything in the oil that was drained from the engine and the nothing was in the filter either. Yes the I cut the filter open.
So I understand your position on the failure, and yes of course Melling is going to say "B.S." but I'm not the only person to ever experience a cam failure of this type. JP Magazine's stroker did the same thing.
So you can believe what you want, but you weren't there and you didn't spend the time on the engine, nor did you exhaust all other possible causes. So please be a decent lad and accept the fact that your opinion is nothing more than that, an opinion.
Back to the original thread, sorry for the hijack.
08-28-2009, 11:18 AM
#29
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where you can get to the lifters via the intake mfld, the L-6 requires a head pull. Big job ...
Don't know exactly how badly the bolts are stripped BUT ... you could try just tapping the holes to see if you can push some metal back into place so a bolt could hold... torque is not much on 'em. If not and you can only get a small bite on the block, you might consider getting some appropriate size studs and mounting them with some green loctite or even JBweld ... a solid stud in there might help to pull that pan back in tight to the block and stop the leak .... of course....if there is room to drill, there is always a helicoil ... more work but the BEST repair possible for a stripped out bolt
Don't know exactly how badly the bolts are stripped BUT ... you could try just tapping the holes to see if you can push some metal back into place so a bolt could hold... torque is not much on 'em. If not and you can only get a small bite on the block, you might consider getting some appropriate size studs and mounting them with some green loctite or even JBweld ... a solid stud in there might help to pull that pan back in tight to the block and stop the leak .... of course....if there is room to drill, there is always a helicoil ... more work but the BEST repair possible for a stripped out bolt
08-28-2009, 11:20 AM
#30
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Pictures don't lie ...
and the cam/lifter failure is painfully obvious. I'm sure the motor failure caused substantial pain to your bank account .. and I'm sorry about that ...also probably bruised your ego too ... after all; it's only human nature to seek out ways and reasons to protect both. Don't blame you for tryin' either ... but you're only foolin' yourself, brother ... your whole 'theory of what happened",your anecdotal stories and convoluted logic are nothing but that ... stories, and wishful thinking. You have offered NOTHING that supports the ridiculous theory that an HV/HP oil pump caused yours or anyone else's motor to fail. Just plain nonsense.
Any oil pump is going deliver slightly greater volume and pressure to ports nearer to the source ... regardless of the brand or whether it's HV/HP or not.
That just wasn't it, Frank, and I didn't/don't have to be there to know with complete certainty that that wasn't it either. I've offered some of the real reasons in an earlier post ... but you ignored them ... after watching all the Melling vids, I could even offer you a few more ... but that would be a waste of time, wouldn't it? You're only interested in the stuff that you think supports your own ****-eyed theory. That's bad science, Frank. You're just not gonna' accept the responsibility ... blame it on something else, right? ... it's the easy way out.
I'm still unclear who put this motor together ... you or the shop?? Regardless of who it was, let me explain to you in the most simple, direct way I know how to WHAT actually caused your motor to fail: MECHANIC ERROR .... more directly; It was the person who either DID or DIDN'T, before installing the motor, put the drill motor on a suitable flat bladed shaft, stick it down the distribuor hole and spin the pump up while watching the oil squirt from each and every rocker arm ... including number 6. Had that been done correctly; any oiling problem would have been discovered at that point and could have/should have been corrected. Accept it or not, Frank ... that IS the bottom line ... not my 'opinion' as you have suggested.
So get a grip, Frank ... own it, if it was you!!
... BTW, I'm 61 ... a bit old for someone to be callin' me a lad. Used to be pretty well known in CS too ... few years with Thouroghbred Mercedes, Datsun, Nissan, Puegot. Owned Action Auto Parts and a carb shop at the corner of Pikes Peak and Academy, behind Senter Tire. Go find a real mechanic like Alex Kaufbush, Salim Nehme, Klaus Gallus, Dan Malloy, Henry Carter, Artie Shaw or John Waldron ... there's a few others too if you really need to know an answer ... they were always helpful to me.
Any oil pump is going deliver slightly greater volume and pressure to ports nearer to the source ... regardless of the brand or whether it's HV/HP or not.
That just wasn't it, Frank, and I didn't/don't have to be there to know with complete certainty that that wasn't it either. I've offered some of the real reasons in an earlier post ... but you ignored them ... after watching all the Melling vids, I could even offer you a few more ... but that would be a waste of time, wouldn't it? You're only interested in the stuff that you think supports your own ****-eyed theory. That's bad science, Frank. You're just not gonna' accept the responsibility ... blame it on something else, right? ... it's the easy way out.
I'm still unclear who put this motor together ... you or the shop?? Regardless of who it was, let me explain to you in the most simple, direct way I know how to WHAT actually caused your motor to fail: MECHANIC ERROR .... more directly; It was the person who either DID or DIDN'T, before installing the motor, put the drill motor on a suitable flat bladed shaft, stick it down the distribuor hole and spin the pump up while watching the oil squirt from each and every rocker arm ... including number 6. Had that been done correctly; any oiling problem would have been discovered at that point and could have/should have been corrected. Accept it or not, Frank ... that IS the bottom line ... not my 'opinion' as you have suggested.
So get a grip, Frank ... own it, if it was you!!
So please be a decent lad and accept