85vet

I know there is another post on melling oil pumps, but I have pics that I believe clearly shows the issues with the new style pump. I installed a new M55 pump 1/2 way thru this past season of 06 and decided to pull it and go with a racing version.
I have pics comparing an original style M55 to a new style M55 to the racing version M10552. I now understand where the issues are and recommmend not using the new style for any high performance motor.

http://s8.photobucket.com/albums/a26...%20oil%20pump/

BadjerJim

WOW - great pics. Really shows what's up.

Thanks!

pablocruise

Excellent work 85. Thank you very much for the pics.
I wonder why melling is doing that? Probably some bean counter at a desk somewhere saying, "We could save .01 on each unit if we use less material on the body". Re-goddam-diculous.

Corvette0096

Congrats on the 10:80.

SloRvette

Melling is doing this as per orders from GM. It's GM specing them to take the material out.

bogus

you know what REALLY gets me... at that location, why would there be cracks from stress? I mean, there should not be enough loading on the case to do this. It's not only less material, it's CHEAPER material!!!

85vet

Allways glad to enlighten the masses.
Corvette0096 - thanks for noticing - good thing that cheap pump did not let go. I would be ashamed to say that it is made in the good ole USA.

Slalom4me

Thanks for the pictures. Too bad we can't keep the Melling info altogether
but I'll create posts to link the threads to each other.

Is there a sleeve in the hole? How many lbs-ft on the bolt?

Can you describe your application.
- Street, drag, AutoX/RR
- Maximum RPM
- Maximum pressure
- OEM, solid or plate-style engine mount

Courtesy of 85Vet

Slalom4me

Here are links to the other two concurrent threads

SAVE YOUR ENGINE-Melling has weakened the casting on their SB and BB oil pumps

Moroso oil pumps

I am including the Moroso thread because, despite a statement
that Moroso does not use the Melling M55, pictures of my Moroso
22100 seem to suggest that it IS based on an M55-style Melling.

,

Sidney004

Even if the material is the same, the design of the casting, the differential cooling rate between the snout and the body after the casting is poured, the porosity, material or mold contamination, etc. can all result in high internal stresses or a fundamentally weak part that will ultimately fail. Just be thankful they are not making landing gear for aircraft. I am surprised these pumps have not failed in non performance applications as well.

85vet

Pump bolt was torqued to 65 ft lbs per specs. See sig for general info - street & drag use. Shifts at 6300rpm. Standard engine mounts with oil pressure at wot to 70lbs, but hot and idle oil at 15lbs. I do use 0-20 redline racing oil.

I raced considerably less this season than in prior years, more street miles like drive to Carlisle. Corkvette is using my original M55 in his 355 and I ran that pump hard.

Midnight 85

I had read the other two posts about Mellings new "redesigned" pumps and since I had just installed a new M55HV in my new 383 I was more than concerned so since I was going to visit my son in Atlanta I knew I would be going to Summit for another pump. While at Summit I found out that Melling makes the Moroso pumps, and Summit's own brand also. The Moroso pump even has the M55HV cast in it. I like a high volume pump so I bought an M10555 for my engine along with a stud kit from ARP to mount it.
Thank you 85vet for the pics, I am really happy I decided to replace the M55HV.
Miris32, sorry I didn't contact you while I was in Atlanta but since the wife has to work tomorrow we spent our much too short weekend with our son. I will get in touch on my next trip down, I promise.

Mr Mojo

All in the name of higher profits by using lesser materials. Nobody cares about quality anymore, just profits.

ZBRA

Same can be said for consumers as well as manufactures/suppliers. Consumers continue to flock to the big-box 70%-China-goods retailers instead of even attempting to support local or smaller businesses that will carry higher quality products.

bogus

this leads to an even bigger problem - the small local businesses are getting into the cheap product craze, too... just to compete.

Several years ago, I went to a local appliance store, wanting to get a Maytag dishwasher... the owner was pushing me - HARD - towards a POS Frigidaire... Made in Mexico! The Frigidaire was all plastic and just junk... all for about $100.00 LESS than the porcilinized metal used in the Maytag. My mom still has the Maytag... I can't attest to how long the Frigidaire would last, but my brother had a nearly identical model, by RCA, and it was worn out after 5 years... the plastic was all stained, the door was weak and flimsy, and it simply didn't clean as well.

It's endemic... and I blame the American consumer for becoming cheapskates.

Melling should be ashamed by this. They are selling a product that directly effects folks who are willing to spend a little more to make something better, and they are selling a piece of **** that will only **** up the investment. Thanks to their warrantee, they are not liable for any failures.

Personally, I am never buying a Melling anything, ever. That's the 2nd company I am putting on my component **** list. To be honest, from all the reading I have done re: oil pumps, I think I will stick with a tried and true GM OEM unit. Perhaps rebuilt, and a little relieved internally.

JLeatherman

I was about to order an M55HV for my new 383 as well. What should I get instead?

Mr Mojo

I delivered this box a while back.

85vet

if Melling - racing series M10552 & buy the pickup for it. The pump is about a 1/2 longer & you may have an issue with a pickup that is based on standard size pump.
Their pickup bolts onto the pump.

Edit:***** Do not buy the melling pickup if you have a pan with baffles in it. Their pickup is for a stock style pan.

JLeatherman

That setup is good for the stock 84 pan? The pickup that Summit sells says "aftermarket pan style." Also, I thought a High Pressure pump was better than a High Volume pump? What motors are each better for?

Midnight 85

High volume means your engine is getting a better supply of oil, most always a good thing. High pressure may not always be a good thing.
I have never used a high pressure pump. I am using pump # M10555 in my new 383 and it takes bolt-on pickup # MEL-12558. Both are available from Summit, that's where I got mine.