[1986c10]

Hi, once again i have another thread to add to my thousand others and i am sorry haha. I have a chevy 350 that i just rebuilt. Its a 92 2 bolt roller and im using the stock pan. I bought from the parts store a melling m-55hv (i asked for an oem one and non-high volume and thats what i got and just realized after installing) and 55-S2 pickup screen. The pan hits the pickup screen at the rear unless i tilt it at about 15-20 degree angle. Is this too much of an angle? Or is that pump supposed to be used with a deeper pan and the oem non-hv pump would fit fine? Thanks in advance.

[eloc431962]

Do you really think you need the HV oilpump ? It works two way's get another pan or go back to the stock non HV oil-pump. it really needs to be sitting as level in the pan as can be and should be in the oil. JMO I have seen people run them like that but not me IMHO. I would take that pump back and get the other pump if it was me, or buy another pan but IMHO you probably don't really need the HV pump anyway. JMO


Cole

[1986c10]

exactly. I didnt want a hv and specifically asked for a standard and they reassured me it was standard, its not and they wont exchange. Im not opposed to running a hv but didnt feel like coughing up the cash for the pan. Do you feel that the hv oil pump is taller for some reason causing the clearance problem? Thanks for the response. I appreciate the input

[adantessr]

I guess that you know by now that the OEM volume pump is the M-55 without the HV. I would bite the bullet and buy the M-55. It is frustrating I know, but it is cheaper than another oil pan. And when you compare the two pumps, I think that you will find that the HV is taller due to it having longer pump gears and housing.

[Richiehd]

Originally Posted by adantessr

I guess that you know by now that the OEM volume pump is the M-55 without the HV. I would bite the bullet and buy the M-55. It is frustrating I know, but it is cheaper than another oil pan. And when you compare the two pumps, I think that you will find that the HV is taller due to it having longer pump gears and housing.

Correct
The pump you want is the Melling SELECT. The m55 and the m55hv had problems with the neck breaking. You should have got a not in the box when you got it. Use only the select series. It comes with a higher pressure bypass also.
Google it, Speedway sells it
Standard volume 10553, comes with a all steel drive too.

[GMC boogie]

I would exchange the pump for a standard volume but, your problem is due to the 55s2 screen.....you need the 55s1

[1986c10]

Yeah, the guy reassured me so many times it was standard volume that i didnt even bother checking the box. But i can get a 7 quart pan with pickup for 90 bucks. Should i do that or just stick with trying to get a standard pickup and pump.

[MouseFink]

I went through the same problem last year with my 4.3L V6. I used a Melling Select 10552 (high volume-standard pressure) which uses a 3/4" pick up tube. Those are rugged oil pumps and have the spur gear shafts extended into the pump bottom cover for better stability. I also used a MSD marine certified distributor gear. The Melling 10552 oil pump spur gears, pump housing, 3/4" pick up tube and bottom cover is 0.457" longer than a standard volume oil pump. That relocates the pick up screen about 1/2" closer to the bottom of the pan. With only 3/8" pan to screen clearance with a standard volume oil pump, you can use simple math and see that a 1/2" deeper oil pan must be used or a 1/2" shorter pick up tube. On a Chevy S10 Blazer 4x4 the pick up iscreen assembly is designed for a stock oil pan that is 9-1/4" deep. In 1992 through 1997, GM started using 3/4" oil pick up tubes on all the Chevrolet 4.3L V6 and SB V8 standard volume oil pumps. The larger diameter pick up tube does not necessarily make the pump a HV oil pump.

In your situation, you should get a Melling Select standard volume/standard pressure oil pump with a 3/4" pick up tube or a Melling M155 oil pump with a Mellimng 155S pick up. The larger 155S pick up tube fits a standard SBC oil pan. The difference between a 5/8" and 3/4" tube is made up with a 1/8" thicker bottom cover on the oil pump that uses a 3/4" pick up tube.

I definately wanted to use a HV pump but only because of the oil cooler, oil tubing and remote filter on a S10 Blazer 4x4. After trying unsuccessfully to fit four different aftermarket pick ups, I finally cut a 1/2" section from the Melling 3/4" S10 Blazer 4x4 pick-up tube and wire-welded it back together with the screen indexed correctly. Shortening the pick-up tube 1/2" worked great leaving 1/2" clearace between the bottom of the oil pan and the pick-up screen.

[1986c10]

thanks for the suggestions. im just gonna toss that pump in the trash and get a standard select pump and use the stock pan. Thanks alot guys in diagnosing my problem!

[1986c10]

one more thing before i order the melling select. it says the gears are 25% longer. To me that sounds like a taller pump and more clearance issues... correct me if im wrong.

[adantessr]

Originally Posted by 1986c10

one more thing before i order the melling select. it says the gears are 25% longer. To me that sounds like a taller pump and more clearance issues... correct me if im wrong.

Sounds to me like the same kettle of fish. I would just install the M-55 and be done. Also, I wouldn't trash that pump. I mean how much storage space does it take? Someone you know may want it someday. Just make sure that it is oiled before you bag it.

[MouseFink]

As I wrote before, all the Melling Select high volume oil pumps have spur gears and a pump housing that is .300" longer (25%) than the standard volume oil pump. The longer spur gears and the thicker bottom cover makes the entire pump .457" longer. That oil pump and a Melling pickup screen will not fit inside a stock oil pan.

You can install a Melling M155 oil pump without any clearance issues. It is a standard volume oil pump that accepts a 3/4" pick up tube assembly. The tube size is the only difference between the M55 and the M155 oil pump.

I read where GM was having warranty problems with some customers engines. The engineers determined that some customers SB V8/V6 engines equipped with oil pumps that had a 5/8" oil pump pickup tube were burning out the main bearings while still under warranty. In 1996 Chevrolet started using 3/4" pick up in all V8/V6 engines and apparently that solved the problem. I have a suspicion that when the engines that burned out the bearings were assembled at the factory, the "hidden plug" under the rear main cap was left out and GM did not want to publicize their poor assembly practices.

[Richiehd]

Originally Posted by 1986c10

one more thing before i order the melling select. it says the gears are 25% longer. To me that sounds like a taller pump and more clearance issues... correct me if im wrong.

Go with the select 10553, standard volume , standard pressure
Google it, comes on on Speedway motors

[1986c10]

thanks mousefink, i'll be going with the m55 because i dont wanna buy a new pan.

that model number is the one i said was 25% longer gears so i'll be getting a m55

[Richiehd]

Originally Posted by 1986c10

thanks mousefink, i'll be going with the m55 because i dont wanna buy a new pan.

that model number is the one i said was 25% longer gears so i'll be getting a m55

That m55 has issues, comes with warning in the box about using on high performance applications, its why I suggested thw Mellin Select