melling oil pump picture thread
- Thread starter sy#2921
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cloneman315
Active member
Re: melling oil pump picture thread
so th eone on the right is weaker?it would seem the one on the left would be
so th eone on the right is weaker?it would seem the one on the left would be
cloneman315
Active member
Re: melling oil pump picture thread
were are the breaking?mine says m55hv is this a problem on the standard and hv pumps?
were are the breaking?mine says m55hv is this a problem on the standard and hv pumps?
Last edited:
sy#2921
BAMF
Re: melling oil pump picture thread
Yes. The one that is currently mounted on the motor is the weak version. It affects both the m55a and m55hv since they changed the casting.
It is cracking clean off the motor where it has that angle upwards next to where the nut is for the mounting stud. The old version on the left is a much better casting quality and has A LOT more material overall.
I measured over 1/4" difference in the thickness of the body, you can see what I am talking about in my last picture. Look at how much the machining "posts" as I call them stick out from the body to make up the difference in casting thickness and no there is no trick to that photo there is that much difference in the overall casting thickness
cloneman315 said:
Yes. The one that is currently mounted on the motor is the weak version. It affects both the m55a and m55hv since they changed the casting.
It is cracking clean off the motor where it has that angle upwards next to where the nut is for the mounting stud. The old version on the left is a much better casting quality and has A LOT more material overall.
I measured over 1/4" difference in the thickness of the body, you can see what I am talking about in my last picture. Look at how much the machining "posts" as I call them stick out from the body to make up the difference in casting thickness and no there is no trick to that photo there is that much difference in the overall casting thickness
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Quickstop [UK]
Combating adversyty.
Re: melling oil pump picture thread
ok as I understand it...
High pressure gets the oil to parts that other pumps don't. This means more oil at higher rpms to the lifters and rockers and just greater penetrating fluid.
High volume will pump a lot more but will be at a lower pressure. The danger is that it will pump the oil from the sump too quickly and you might actually lose oil to the parts of the engine that need it at a critical time.
It is similar to the injectors - you can have high pressure but with reduced volume - in order to have both you need a monster pump.
That is a very basic understanding so I could be wrong.....
ok as I understand it...
High pressure gets the oil to parts that other pumps don't. This means more oil at higher rpms to the lifters and rockers and just greater penetrating fluid.
High volume will pump a lot more but will be at a lower pressure. The danger is that it will pump the oil from the sump too quickly and you might actually lose oil to the parts of the engine that need it at a critical time.
It is similar to the injectors - you can have high pressure but with reduced volume - in order to have both you need a monster pump.
That is a very basic understanding so I could be wrong.....
cloneman315
Active member
Re: melling oil pump picture thread
so what number do u want for our motors with a stock pan?u want a hp not a hv?part numbers and pickup number?thanks a bunch
so what number do u want for our motors with a stock pan?u want a hp not a hv?part numbers and pickup number?thanks a bunch
sy#2921
BAMF
Re: melling oil pump picture thread
I ordered the 10550 hv pump and the mel-210s melling pickup. Like I stated in the other thread, I have been told by a few engine builders that a high volume pump will give you higher pressure as well. Also, there is a second spring that comes with the hv pump to bump up the pressure if you want to.
I just plan to run a tad extra oil in the sump with my hv pump and not worry after that
I ordered the 10550 hv pump and the mel-210s melling pickup. Like I stated in the other thread, I have been told by a few engine builders that a high volume pump will give you higher pressure as well. Also, there is a second spring that comes with the hv pump to bump up the pressure if you want to.
I just plan to run a tad extra oil in the sump with my hv pump and not worry after that
cloneman315
Active member
Re: melling oil pump picture thread
thanks so you are running a hv pump also?so let me get this right even the hv pumps had this problem also,not just the standard ones?
thanks so you are running a hv pump also?so let me get this right even the hv pumps had this problem also,not just the standard ones?
sy#2921
BAMF
Re: melling oil pump picture thread
I am running the 10550 hv pump and put the heavier spring in to give a little more pressure as well.
All m55 series pumps have been changed to the new thinner/weaker style casting and only the m-select (1055x) series are the thicker/(stronger) castings
I am running the 10550 hv pump and put the heavier spring in to give a little more pressure as well.
All m55 series pumps have been changed to the new thinner/weaker style casting and only the m-select (1055x) series are the thicker/(stronger) castings
Sy Guy 0024
Member
Re: melling oil pump picture thread
I'm running the 10550 pump and 210s pickup as well. However, I'm using the lower-pressure spring since the higher volume should bump the pressure over stock anyway.
I'm running the 10550 pump and 210s pickup as well. However, I'm using the lower-pressure spring since the higher volume should bump the pressure over stock anyway.
cloneman315
Active member
Re: melling oil pump picture thread
ok so most guys are running high pressure not high volume?
ok so most guys are running high pressure not high volume?
Re: melling oil pump picture thread
Melling Select 10552 10% higher volume - standard pressure, 3/4" inlet.
259 pick up screen assembly 3/4" for 9-1/4" deep oil pan, oil cooler and remote oil filter 4WD.
The pick up must be shortened 1/2" to fit the oil pan because the Melling Select 10552 oil pump housing is .487" longer than a standard volume or stock oil pump.
1992 and later Chevrolet 4.3L V6 oil pumps have a 3/4" inlet.for no more than 5% higher volume than the standard 1985-1991 oil pumps that use a 5/8" inlet. . Chevy 4.3L V6 engines do not have priority main bearing oiling like a SBC V8 engine and the front main bearings on the V6 engines can fail at high RPM (5000+ RPM) due to lack of oil volume. For anything except a grocery getter, the Chevy 4.3L V6 engine needs 10% higher volume and a 21 PSID oil bypass valve in the block. The 21 PSID by pass valve is GM 25014612. The Chevy 4.3L V6 engines came with 11 PSID by pass valve because those engine were red-lined at 4700 RPM with a standard volume oil pump. .
Using a higher volume oil pump is especially important on vehicles with an oil cooler and/or remote oil filter. The stock 11 PSID oil pressure by pass valve in the remote oil filter adapter on the left front fender is not a problem and does not need to be replaced with a 21 PSID by pass valve for high performance engines. . .
Melling Select 10552 10% higher volume - standard pressure, 3/4" inlet.
259 pick up screen assembly 3/4" for 9-1/4" deep oil pan, oil cooler and remote oil filter 4WD.
The pick up must be shortened 1/2" to fit the oil pan because the Melling Select 10552 oil pump housing is .487" longer than a standard volume or stock oil pump.
1992 and later Chevrolet 4.3L V6 oil pumps have a 3/4" inlet.for no more than 5% higher volume than the standard 1985-1991 oil pumps that use a 5/8" inlet. . Chevy 4.3L V6 engines do not have priority main bearing oiling like a SBC V8 engine and the front main bearings on the V6 engines can fail at high RPM (5000+ RPM) due to lack of oil volume. For anything except a grocery getter, the Chevy 4.3L V6 engine needs 10% higher volume and a 21 PSID oil bypass valve in the block. The 21 PSID by pass valve is GM 25014612. The Chevy 4.3L V6 engines came with 11 PSID by pass valve because those engine were red-lined at 4700 RPM with a standard volume oil pump. .
Using a higher volume oil pump is especially important on vehicles with an oil cooler and/or remote oil filter. The stock 11 PSID oil pressure by pass valve in the remote oil filter adapter on the left front fender is not a problem and does not need to be replaced with a 21 PSID by pass valve for high performance engines. . .