12 replies to this topic

[Lmcgrew79]

Should i rebuild or replace?

 

Took the oil pump apart and checked the specs according to the manual.

 

Pressure Spring was at 44.7 mm 1 small washer makes it correct, or i could just order the spring for 3 dollars. Plunger looked pretty good.

 

Rotor to rotor clearance was in the middle of the spes, but outer rotor to housing was at .017 toward the loose end of spec. Wasnt any noticable wear marks in the casting or on on the rotor.

 

The oil pressure on the car seems a bit low at higher rpm, sadly i dont know if it is the gauge the wear in the rod bearings or the oil pump causing the lower pressure. 

 

 

 

 

[Jim Drago]

Replace they are cheap. 

One spec of debris, one mistake there and the motor is done.

[Lmcgrew79]

Thanks Jim i see some that are cheaper and oem seems higher, does the oil pump have to be oem?

[Steve Scheifler]

It does not need to be OEM. We have used several different brands and never had a problem, but others may have different experience.

[Steve Scheifler]

One thing I did run accross was a pump for the short-nose 1.6 which also fit a FWD model with the dip stick hole in the pump housing. Things got a little messy during break-in.

[tom1977]

Mazda will supply part number for the plug for the fwd dipstick hole. I just went through this past month. Under two hundred for oem from mazda speed. My oil pump was in spec, but the relief bore was scarred really bad, as Jim said, oil pump should be replaced for good insurance of new engine build.

[Brian129]

Mazda will supply part number for the plug for the fwd dipstick hole. I just went through this past month. Under two hundred for oem from mazda speed. My oil pump was in spec, but the relief bore was scarred really bad, as Jim said, oil pump should be replaced for good insurance of new engine build.

 

This is another reason to replace!!!

 

I had to pull the motor out of my car after 1 event from build, The relief valve stuck in a nasty bore I did not check.  
Luckily it happened coming off the trailer at home,  so I saved the engine,  But the last thing it was doing before going on the trailer was full on beating at Roebling.   

 

Cheap insurance.  Remember to replace oil pump is pull engine and disassemble,  or you can try to sneak the pan off after removing the whole front subframe.  PITMFA!!!!!

[Lmcgrew79]

Went ahead and ordered one from mazda speed today.

[MPR22]

Went ahead and ordered one from mazda speed today.

Now make sure your plunger moves freely in the bore before install.  Usually requires a very lite honing of the bore. 

[Alberto]

Sharing my experience with oil pumps hoping it is helpful and may save someone a few $:

http://blog.miatarac...ed-to-know.html

 

Someone please correct me if anything there is wrong

[Lmcgrew79]

Now make sure your plunger moves freely in the bore before install.  Usually requires a very lite honing of the bore. 

Wow, even on a new one? Obviously it needs assembly lube, ill check it when it gets in.

[tom1977]

I didn't think to hone my new one... I did open it and use assembly lube in the main gear and bypass

[Steve Scheifler]

Went ahead and ordered one from mazda speed today.

As much as I appreciate the MazdaSpeed program, I find it very difficult to justify paying more than 3x the price of an aftermarket part unless there is good reason to believe the OEM is better.