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Oil pump (crankshaft front) oil seal failures


Chris Wilson

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I haven't been following Supraforums much recently due to the lack of "new posts" button but is anyone there having these woes with defective pumps?

 

Has anyone posted a link to this thread up there for their input on the subject? Just wondering if we can pull in more ideas really.

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No it is not a wind up.

 

Brand new from PHR with I might add the new casting pump housing, put it on the car and hey presto leaking from the same hairline crack running down the reilef valve housing as the other new pumps.

 

Really strange sight to see as the oil appears as a line at the bottom and then works it's way up to the bolt then pours out.

 

Shame I did not have a video camara as it is the first time I have ever seen oil go up.

 

I am starting to wonder if the castings can be reinforced with maybe weld, i think the PRV bore would have to be machined, but the whole pump issue is getting redicules! don't buy one from the UK just because of this, and the fact that it would supposedly be a batch quality issue! but if they are coming in from the US and failing then Toyota have got a big problem!

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I personally don´t think that this damn crank seal problem is crank case pressure related.......

For me it has something to do with the oil pumps and maybe with the restrictive stock oil cooler.

 

I have a PHR engine with a PHR oil pump.

I also have the stock oil cooler removed and a Greddy 16 row relocator kit mounted.

I have a catch can vented to air with two big filters to ensure that all pressure can be vented as fast as possible.

 

I run Valvoline 20W60 mineralic oil (mineralic was recommended from Jarrett@PHR).

 

I run 1,7 bar of boost all day and see as much as 9,5 bar!! of oil pressure at WOR in higher rpm`s.

I run the car on the street (highway) on the 1/4 mile and on the round course.....

 

No seal problem as of yet (knock on wood).

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an interesting read! for my own 2p worth ,as the n/a does not have the failure rate ,it is boost related ,and crankcase pressure related -probably not enough venting ,and too much blow by,caused by too much loading on the piston rings-poor sealing-high boost-too hot-glazing-or whatever

simple to prove just add more venting -

my2p

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an interesting read! for my own 2p worth ,as the n/a does not have the failure rate ,it is boost related ,and crankcase pressure related -probably not enough venting ,and too much blow by,caused by too much loading on the piston rings-poor sealing-high boost-too hot-glazing-or whatever

simple to prove just add more venting -

my2p

 

 

 

Been done by a couple of people, i think Jamie has larger breather hoses/take offs, and his still failed.

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Guest 87gtNOS
I personally don´t think that this damn crank seal problem is crank case pressure related.......

 

I run 1,7 bar of boost all day and see as much as 9,5 bar!! of oil pressure at WOR in higher rpm`s.

 

Hey guys! I am the guy sending the seals to Jamie. It is my opinion that there are many other factors here...like deto lifting a head and pressurizing the crankcase, etc...

 

As for the comment here that appears to be comparing 1.7 bar of boost to 9.5 bar of oil pressure is apples to oranges. Oil pressure will not blow out the seal as there is no 'pressure' present in the oil pan from the oil's 'pressure'. Oil being forced by the pump into bearing journals creates the pressure you see on a gauge.

 

Now, 1.7bar from the turbo, released into the crankcase is gonna find it's way out the weakest link! Like this front seal!!

 

In Jamie's case, I think it may have lifted the head or split a head gasket, then screwed up the seal from the excessive pressure in the crankcase.

 

Anyways, just my opinion, only trying to through ideas out there for you all!

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When I come back I am going to see if it's feasible tu run a pressure take off from behind the seal, where the drain slot and hole is, and see if I can get a reading of any oil pressure that may build up there. I n theory it should be zero. If there is oil pressure there it's becsuse the rotor front face annular ring area is leaking pressurised oil into the cavity to such an extent the drain hole is overcome. I still think something definitive could be gleaned from a proper examination of a pump and seal, as removed as a unit, from an engine with this issue.

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Guest 87gtNOS

Chris, oil pressure will be the same in any part of the oil system that is after the pump.

 

The pressure you may find is air....from boost! I suggested that Jamie somehow measure pressure coming out of the exhaust side valve cover. Take a mity-vac (which can measure psi also) and plumb it into the car and watch it as you drive for any spikes in pressure. Or put the car on the dyno (where a load is present) and stick the gauge on and watch it. You'll need to be under load. The air pressure will push oil out the seal, the air pressure does this because it is likely causing the oil to be 'splattered' everywhere in there.

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"Been done by a couple of people, i think Jamie has larger breather hoses/take offs, and his still failed."

 

Im talking huge amount of blow by -under high boost pressure-for a very short period ,far more than could be vented with a "larger hose" enough to blow a oil seal type volume of air but not long enough duration to say push out the dip stick (another extra vent source)

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"Been done by a couple of people, i think Jamie has larger breather hoses/take offs, and his still failed."

 

Im talking huge amount of blow by -under high boost pressure-for a very short period ,far more than could be vented with a "larger hose" enough to blow a oil seal type volume of air but not long enough duration to say push out the dip stick (another extra vent source)

 

 

This is the bit i have a problem with, i understand what your saying, but i fail to see that given a very short duration of high pressure, but i fail to see how this pressure could be transfered quick enough to blow out a seal through a 1/8" or smaller drain hole, as it would be a lot easier to disperse this pressure through the 1/2" dia dip stick hole which is also fed from the sump.

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Chris, oil pressure will be the same in any part of the oil system that is after the pump.

 

The pressure you may find is air....from boost! I suggested that Jamie somehow measure pressure coming out of the exhaust side valve cover. Take a mity-vac (which can measure psi also) and plumb it into the car and watch it as you drive for any spikes in pressure. Or put the car on the dyno (where a load is present) and stick the gauge on and watch it. You'll need to be under load. The air pressure will push oil out the seal, the air pressure does this because it is likely causing the oil to be 'splattered' everywhere in there.

 

I put a peak hold pressure gauge onto the dip stick tube,so direct from crankcase, but got no positive pressure reading.

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When I come back I am going to see if it's feasible tu run a pressure take off from behind the seal, where the drain slot and hole is, and see if I can get a reading of any oil pressure that may build up there. I n theory it should be zero. If there is oil pressure there it's becsuse the rotor front face annular ring area is leaking pressurised oil into the cavity to such an extent the drain hole is overcome. I still think something definitive could be gleaned from a proper examination of a pump and seal, as removed as a unit, from an engine with this issue.

 

If you do see pressure there, how will you be certain what is causing it? By taking a clear tube off and seeing if pure oil or aerated oil flows out?

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If you do see pressure there, how will you be certain what is causing it? By taking a clear tube off and seeing if pure oil or aerated oil flows out?

 

Or connecting that tube to the sump/catchcan. That would confirm wether its a hydraulic issue.

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Or connecting that tube to the sump/catchcan. That would confirm wether its a hydraulic issue.

 

I don't follow.

 

Measuring pressure in the crankcase AND behind the oil seal would tell you if any pressure behind the seal was due to crankcase pressurisation (you would see pressure in both places). Pressure behind the seal and NO pressure in the crankcase would mean any pressure behind the seal was probably from leaking oil.

 

Catch cans are a lousy place to measure crankcase pressure, by the way. Measure it at the dipstick tube or a modified oil filler cap.

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I don't follow.

 

I think what charlie is saying is that if you feed the pipe that chris is talking about on backside of the seal to the crankcase then the seal will be pressure blanced. There's a couple of assumptions there though...eg the pressure drop along the pipe would have to be negligible (short smooth large dia pipe). If the seals stop blowing then there's a case for crankcase pressure being the problem. If no change then it must be oil pressure or a physical issue like surface finish/installation etc

 

I think that too much crank case pressure would first blow out the oil dip stick not the front seal........

Again, I don´t think the problem is crank case pressure related......

 

For the same crankcase pressure the force acting on the seal is much much higher than that acting on the dipstick - something like 13-14 times more force. I don't have exact dimensions so that's a rough number. If people are lubing the seal OD whe they install them then the friction holding resisting that force will be very low - I'm not sure how you can make a blanket statement about the dipstick blowing first, anything to back that up?

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Ha, i also know of a brand new phr pump that has failed recently, im not sure the owner wants to come public with it though so ill name no names.

 

Thanks Jamie. I only wanted to keep it quiet while things were up in the air. Im now running the car as happy as larry without any big issues so no secret now.

 

Reading this thread practically daily as gutted for you, hope you dont get too pissed off with it and it gets sorted soon!

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