Oil circulation problem

[DAK]

I have a problem with oil circulation in a '91 Seca (4A-FE engine with 190k km on the clock). The engine cut out suddenly after a few km from a cold start with bottom end knock. At the time it happened, a guy from roadside assistance found most of the oil in the top end of the engine obviously under pressure because it sprayed out when he opened the oil cap. His opinion was that he thought a faulty oil pump might be the cause but I'm not so sure and I'm wondering whether the oil pressure release valve is the problem. I've checked the oil level in the engine since getting the car transported home and its sitting between min and max so the oil level itself wasn't the cause. Also, there was no indication from engine performance in the lead up to the problem occurring that there was a problem brewing.

So I'm wondering whether anyone else has suffered a similar situation and, if so, whether I'm right about a stuck or faulty oil pressure release valve. I would value your opinions or advice before starting to pull apart the engine- thanks.

[supertownace]

I have a problem with oil circulation in a '91 Seca (4A-FE engine with 190k km on the clock). The engine cut out suddenly after a few km from a cold start with bottom end knock. At the time it happened, a guy from roadside assistance found most of the oil in the top end of the engine obviously under pressure because it sprayed out when he opened the oil cap. His opinion was that he thought a faulty oil pump might be the cause but I'm not so sure and I'm wondering whether the oil pressure release valve is the problem. I've checked the oil level in the engine since getting the car transported home and its sitting between min and max so the oil level itself wasn't the cause. Also, there was no indication from engine performance in the lead up to the problem occurring that there was a problem brewing.

So I'm wondering whether anyone else has suffered a similar situation and, if so, whether I'm right about a stuck or faulty oil pressure release valve. I would value your opinions or advice before starting to pull apart the engine- thanks.

did he remove the cap when the engine was running??. f he did then i would suggest that you have worn rings/pistons/cylinders...this lets some of your compression past the pistons and into the sump....when you take the cap off you let the pressure out

what gives you the idea that its bottom end knock??..is it still there?? or only under certain conditions??.

a faulty pressure relief in an oil pump wont send all the oil to the top of the engine. i owned an ae92r corolla for 6 years...had the problem of most of the engine oil being in the rocker cover and ending up going out the pcv valve and into the engine...it made HEAPS of smoke out the back!!!... i found it to be the engine oil was too thick for this particular engine and so changed it to a 10w 40 grade oil and never had the problem again

if the noise is a crank issue then most likely you've spun a bearing or 2.

cheers

[DAK]

I have a problem with oil circulation in a '91 Seca (4A-FE engine with 190k km on the clock). The engine cut out suddenly after a few km from a cold start with bottom end knock. At the time it happened, a guy from roadside assistance found most of the oil in the top end of the engine obviously under pressure because it sprayed out when he opened the oil cap. His opinion was that he thought a faulty oil pump might be the cause but I'm not so sure and I'm wondering whether the oil pressure release valve is the problem. I've checked the oil level in the engine since getting the car transported home and its sitting between min and max so the oil level itself wasn't the cause. Also, there was no indication from engine performance in the lead up to the problem occurring that there was a problem brewing.

So I'm wondering whether anyone else has suffered a similar situation and, if so, whether I'm right about a stuck or faulty oil pressure release valve. I would value your opinions or advice before starting to pull apart the engine- thanks.

did he remove the cap when the engine was running??. f he did then i would suggest that you have worn rings/pistons/cylinders...this lets some of your compression past the pistons and into the sump....when you take the cap off you let the pressure out

what gives you the idea that its bottom end knock??..is it still there?? or only under certain conditions??.

a faulty pressure relief in an oil pump wont send all the oil to the top of the engine. i owned an ae92r corolla for 6 years...had the problem of most of the engine oil being in the rocker cover and ending up going out the pcv valve and into the engine...it made HEAPS of smoke out the back!!!... i found it to be the engine oil was too thick for this particular engine and so changed it to a 10w 40 grade oil and never had the problem again

if the noise is a crank issue then most likely you've spun a bearing or 2.

cheers

[Hiro]

Blocked oil drain in the head maybe?

[DAK]

Thanks very much for your reply 'Supertownace'. I'll try and answer the very useful points you have raised.

I wasn't present at the time the guy opened the cap but I have since tried it myself with the engine running and apart from some splashes the oil doesn't seem to be under pressure. Unfortunately my wife who was present can't remember whether the engine was running........I'm sure it must have been.

As I said, I've run the engine but it doesn't sound good! It knocks badly for the first second or two on a cold start but then runs quietly. Once it warms up, it starts knocking again under load. What I don't understand about the circumstances leading up to the problem in the first place though is that there were no signs of an impending issue with either engine noise or fall in performance. It ran very sweetly (no oil burn) .....but it certainly doesn't now (still no oil burn).

Oh well.........an engine rebuild will keep me busy for a while. Thanks again for your helpful comments.

I have a problem with oil circulation in a '91 Seca (4A-FE engine with 190k km on the clock). The engine cut out suddenly after a few km from a cold start with bottom end knock. At the time it happened, a guy from roadside assistance found most of the oil in the top end of the engine obviously under pressure because it sprayed out when he opened the oil cap. His opinion was that he thought a faulty oil pump might be the cause but I'm not so sure and I'm wondering whether the oil pressure release valve is the problem. I've checked the oil level in the engine since getting the car transported home and its sitting between min and max so the oil level itself wasn't the cause. Also, there was no indication from engine performance in the lead up to the problem occurring that there was a problem brewing.

So I'm wondering whether anyone else has suffered a similar situation and, if so, whether I'm right about a stuck or faulty oil pressure release valve. I would value your opinions or advice before starting to pull apart the engine- thanks.

did he remove the cap when the engine was running??. f he did then i would suggest that you have worn rings/pistons/cylinders...this lets some of your compression past the pistons and into the sump....when you take the cap off you let the pressure out

what gives you the idea that its bottom end knock??..is it still there?? or only under certain conditions??.

a faulty pressure relief in an oil pump wont send all the oil to the top of the engine. i owned an ae92r corolla for 6 years...had the problem of most of the engine oil being in the rocker cover and ending up going out the pcv valve and into the engine...it made HEAPS of smoke out the back!!!... i found it to be the engine oil was too thick for this particular engine and so changed it to a 10w 40 grade oil and never had the problem again

if the noise is a crank issue then most likely you've spun a bearing or 2.

cheers

[DAK]

........I might need some neuro surgery then........LOL

Blocked oil drain in the head maybe?

[supertownace]

the "knock" you speak of definately sounds like a spun or worn big end and/or main bearing. it can happen anytime. it mainly happens if you have:

worn bearing shells

big end caps that have had the bolts stretch (either by excessive heat or over revving)

installed the conrods/pistons the wrong way (yes this IS possible)

a worn crankshaft with new bearings (the common one is where you fit standard bearings on an undersize crank)

an engine oil pump that has its pressure relief valve set WAY too high and pushes bearings out (have seen this in a high performance v8 marine engine)

this knock will not cause the engine to burn oil....that is caused either by

worn rings/pistons/cylinders

worn valve stems

worn valve guides

hard or cracked valve stem seals

i have also seen a car burn its auto tranny oil....this was caused from the modulator valve on the tranny letting go

cheers