miatata

So I just had an oil pump failure after putting a brand new oem mazda pump into a JDM import engine into the car. It was seemingly running fine at ~8-9psi 190whp for about 3 months. Then one day I start it and there is no oil pressure. It was down about a quart but it seemed to have come out of nowhere.

Is the harmonic balancer the same thing as the crank pulley? I used my crank pulley and crank sensor wheel from my 97 motor onto this 1.8L from Japan of which I don't know the year. Huge mistake? Could that potentially cause a premature oil pump failure? I haven't found out what happened to this oil pump yet, the engine is still in the car. Either the gears are shredded or the relief valve is stuck open right? What else could cause this?

fooger03

iTrader: (2)

A: The 'harmonic balancer' is indeed integrated into the main crank pulley.

I don't know that there's a difference between 1.6 and 1.8 crank pulleys. If there is a difference, then a swap isn't something that a lot of people consider doing. It just doesn't come up as an issue.

I want to make sure that it's the oil pump and not a sensor/gauge. Unless there were loud discomforting sounds coming from the engine, or unless the "HLA Tick" was much louder than normal (ticking from valvetrain area) then your oil pump may not be the issue. Make sure that your ground wire which attaches between the engine, at the oil dipstick bolt location, and the unibody beneath, and to the mechanics left, of the brake master cylinder, is secured with tight bolts. If you've used the body mount location to secure a heat shield, that bolt can come loose and result in a malfunctioning OPG if not torqued correctly.

miatata

I only swapped 1.8L crank pulleys and added the crank angle sensor plate behind the pulley. I haven't witnessed the car yet but from what I am told it is making the loud and awful "something is wrong" HLA noise.

fooger03

iTrader: (2)

I vote for a blown/missing oil pickup tube gasket

Was the car not started for awhile? a few days? a week?

Prime the oil pump manually. You'll likely have to disconnect the alternator tightening bracket to get to the hex bolt, IIRC it's a 6mm allen key. Find a way to get a couple pints of oil forced into this port. A pump which starts full of oil will draw a heck of a lot more vacuum than a pump which starts full of air. If you've got a small leak somewhere (pickup tube nick/gasket) you may get decent oil pressure when you finally start the car. I'm assuming there's no grinding going on when the engine is turning over, and there wasn't a serious 'click/bang/boom' at the point that the car lost pressure. I'm also assuming that the car didn't lose pressure while the engine was running, but rather the car was started one day and simply did not have pressure...

miatata

No, the car was driven daily. It did not lose pressure while driving to my knowledge. By priming the pump this way if we got pressure again, that would demonstrate that the pickup is leaking? The pickup goes from the oil pan to the oil pump, correct?

Savington

iTrader: (31)

Are you sure it's not just the gauge? The OE gauges don't fail often, but they do fail. If you don't hear metal thrashing, it's the relief valve. It's very odd for one to just stick open like that after a few months of use.

secretsquirrel

Are you using one of these ^, i.e. an OEM part or an "infamous" underdrive pulley (no balancer)?

miatata

For the moment that it was started we definitely did not have oil pressure. He heard loud metal noises and we have heard the sound of an engine without oil pressure previously unfortunately. I can't tell you what the sound was like, I was not there. Last time I heard it, it was like VERY loud HLA tick. I'm using an OEM pulley from a 97 motor installed onto an unknown year 1.8L engine from Japan.

If someone wants to buy my car PM me lol (no parting yet)

fooger03

iTrader: (2)

Japanese engines only have to last like 40,000 miles anyways, right? lol

Sorry about your oil pump failure...if there was any metal crunching noises before the oil pressure dropped, then your oil pump is definitely toasty.