Oil Viscocity with HV oil pump question.

[big66440]

I just replaced my stock oil pump with a high volume one and I'm surprised as to how much of a power loss it caused, I was wondering what you guys think of using synthetic 5W-20 instead of 10W-30 to get back some of that lost power? do you guys think it will be too thin and cause damage? thanks.

[A-man930]

This is a new one for me... why did you install the pump in the first place?

[big66440]

I replaced my oil pan gasket, rear main seal and flexplate. I thought it would be a good idea to put a new pump and screen while I was in there.

[yxmj]

Just MHO but I think you might have other issues

I have never heard of loss of power from an oil pump change.

Do you get the power back when it warms up? Because that different temp would be equivalent (roughly) to the different viscosity of the 2 oils you mentioned....

Put it this way....when I do an oil changes I often dump the oil and then put in 5 liters of diesel and run it up to temp with the diesel (then drain the diesel and put in new oil and filter) and there is no noticeable power loss or gain.

If you had temp extreme... from a hot to a cold...the oil would possibly make a slight difference.

I would look at everything you did while you were in there first....somthing else is the cause of the power loss..... :dunno:

[64 Cheyenne]

High volume oil pump on an old worn engine = possible spun bearing.

[Marine1Texas]

I think there must be a underline effect here.

A oil pump takes very very very little power from the engine, your talking maybe a 1/8 or 1/16 of a hp. you should not notice that at all. As above stated are you seeing power lost when cold or hot, or all the way around? I like to know what your psi now and before, is it around the same? 

If your psi is too high in the crank case you can cause rings to have blow by causing power loss, however you would notice the burning of oil smell I would think. 10 oil weight is perfect down to below freezing and 30 is good for most places in America. When you start the motor the oil it is the thinnest it will be, and it is very thin, once heat is applied it will start to firm up. 5 will act the same as 10 at the same temp since oils with multiple velocities act the same at the same temps. 5 means it does better below freezing. I would never put 20 never less then 30 since the temps of your engine is high. 20 can only get so thick and would remain thin causing easier metal to metal. When you bump up to 40 or 50 it covers for high temps to keep the oil thicker at high temps. Thin oil will cause early death to most motors that run nice and hot like our 4.0's do....

As above said go thru what you did in the process of tare down and put back together!

[cruiser54]

I have a HV oil pump and run Rotella 15/40 year round.

 

Runs like a SCALDED dog. 

[A-man930]

Wow. Lots of misinformation in this thread.

In short, something likely happened during the install or you've had some kind of catastrophic failure (i.e. main bearing).

 

Do some research (from a trusted resource) on multi-grade oils and viscosities.

[HOrnbrod]

Runs like a scalded dog. 

 

I believe the dog part.   :rotf:

[big66440]

There's no noise coming from the bottom end and I have great oil pressure so that eliminates the spun bearing idea, I'm starting to think the distributor index may have been thrown off a bit when I pulled it to prime the new pump? It's not a night and day difference like I struggle to get on the freeway and up to speed, it could also just be my mind playing tricks?

[cruiser54]

Gotta index the distributor. Here's how:

 

http://cruiser54.com/?p=68

[big66440]

Thanks cruiser, I'll update you guys on what I come up with.

[64 Cheyenne]

I did not say "you have a spun bearing" I was stating that when you take an older engine with increased clearances, add a new high volume pump, there is more of a  possibility of the increased pressure to more or less "float", for lack of a better word, the cam, main/rod bearings out off or off their journals resulting in a spun bearing.

[big66440]

I did not say "you have a spun bearing" I was stating that when you take an older engine with increased clearances, add a new high volume pump, there is more of a  possibility of the increased pressure to more or less "float", for lack of a better word, the cam, main/rod bearings out off or off their journals resulting in a spun bearing.

So you're saying that installing a new High Volume oil pump will cause the "crush" ( which is the ONLY thing that keeps bearings in place ) to somehow be decreased allowing main,rod and cam bearings to "float" away and seize onto the rotating crank shaft or camshaft? :hmm:

[64 Cheyenne]

 

I did not say "you have a spun bearing" I was stating that when you take an older engine with increased clearances, add a new high volume pump, there is more of a  possibility of the increased pressure to more or less "float", for lack of a better word, the cam, main/rod bearings out off or off their journals resulting in a spun bearing.

So you're saying that installing a new High Volume oil pump will cause the "crush" ( which is the ONLY thing that keeps bearings in place ) to somehow be decreased allowing main,rod and cam bearings to "float" away and seize onto the rotating crank shaft or camshaft? :hmm:

 

 

Crush?

 

Sheesh, never mind, cause nowhere did I say it "it will cause" I was stating as was told to me by an engine builder who does it for a living that it is possible.

Reason I was told this is that my lower end, and lifters sounded noisy to me, I was wanting to quiet it some, thinking low oil pressure was the culprit, granted I have low press at idle, but is in the middle of the gauge at speed, His recommendation, if I insisted on a new oil pump was to replace it with a stock spec oil pump (which I never did). Four years later and a  bunch of 4k+ runs later, engine still going strong, piston slap still sounds the same, kind of like a diesel when its idling. Miles on the engine...really? Ive had this truck since I think 08, 2 clusters, 3 transmissions, 2 transfer cases later...odometer says I think about 170k but who knows for sure. When the engine decides to give up, I just pull one from stock or finish the HO I have on the engine stand.

[big66440]

 

 

I did not say "you have a spun bearing" I was stating that when you take an older engine with increased clearances, add a new high volume pump, there is more of a  possibility of the increased pressure to more or less "float", for lack of a better word, the cam, main/rod bearings out off or off their journals resulting in a spun bearing.

So you're saying that installing a new High Volume oil pump will cause the "crush" ( which is the ONLY thing that keeps bearings in place ) to somehow be decreased allowing main,rod and cam bearings to "float" away and seize onto the rotating crank shaft or camshaft? :hmm:

 

 

Crush?

 

Sheesh, never mind, cause nowhere did I say it "it will cause" I was stating as was told to me by an engine builder who does it for a living that it is possible.

Reason I was told this is that my lower end, and lifters sounded noisy to me, I was wanting to quiet it some, thinking low oil pressure was the culprit, granted I have low press at idle, but is in the middle of the gauge at speed, His recommendation, if I insisted on a new oil pump was to replace it with a stock spec oil pump (which I never did). Four years later and a  bunch of 4k+ runs later, engine still going strong, piston slap still sounds the same, kind of like a diesel when its idling. Miles on the engine...really? Ive had this truck since I think 08, 2 clusters, 3 transmissions, 2 transfer cases later...odometer says I think about 170k but who knows for sure. When the engine decides to give up, I just pull one from stock or finish the HO I have on the engine stand.

 

What do you say we call it a truce (I'm not a big fan of arguing on the internet) I didn't mean to come off as arrogant or a "know it all " with my previous statement :cheers: . I re indexed the distributor and replaced one of my cracked vacuum caps and it's running much better :D, I can't thank Cruiser enough for putting so much time and effort into teaching us what he knows :thumbsup: .

[cruiser54]

Thanks for reporting back. 

[big66440]

Not a problem :thumbsup:

[64 Cheyenne]

:cheers:

[Eagle]