High oil pressure
Discussion
CrutyRammers said:
Evoluzione said:
Some pictures posted up would help a lot, you're asking us to advise blind while you look at the pics....
Look at the diagram you posted up, you can clearly see bypass valve inside oil filter (as it normally is).
What you may have been fiddling with is the thermostat, you may well have put some part of that (and part of the actual pressure relief valve) back incorrectly or it has dirt on it and has stuck.
Yeah sorry!Look at the diagram you posted up, you can clearly see bypass valve inside oil filter (as it normally is).
What you may have been fiddling with is the thermostat, you may well have put some part of that (and part of the actual pressure relief valve) back incorrectly or it has dirt on it and has stuck.
It's not the thermostat, I know what bit that is
. But I think the manual was misleading me - the key to the diagram above says that number 6 ("oil pressure limiting valve") "controls system pressure". But really it's a bypass valve to allow flow around the oil filter if it's blocked? In which case, removing it wouldn't have affected the pressure, which fits with what I saw.Then I remembered that the oil pump also has a spring loaded valve in it - it's in the housing circled:
As I recall there's a plunger and spring, held into the housing by a split pin. I guess that it's this which actually regulates the pressure, and which I need to look at.
Well, I think I've found the problem.
I dropped the sump tonight. Although the pump is virtually impossible to remove without taking off most of the front of the engine, its bottom cover can be removed and it's this which contains the relief valve:
As soon as I had the cover on the bench, and having seen photos of other pumps, I realised my mistake. The spring is held in place with a little metal cup, which is held in by a split pin. I had put the cup open-end-out, like this:
Whereas the spring should sit inside the cup, like this:
So I'd effectively compressed the spring by 3 or 4mm more than it should have been.
I've just come back from the garage having put it all together, and a quick run (after cranking with coils disconnected to prime the system) showed 80-85psi at idle on my new mechanical test gauge. So that's bang on Evoluzione's 6 bar It still peaked at about 100 when revved but it's clearly dropped a good 30 or 40psi.
So from my previous results I can surmise that it'll drop down to around 20-30 at idle when warm, which'd be about right.
So a simple build error on my part, but I think that's sorted it. Now I'm off to wash the oil out of my nasal cavity/hair/eyes/ etc.
I dropped the sump tonight. Although the pump is virtually impossible to remove without taking off most of the front of the engine, its bottom cover can be removed and it's this which contains the relief valve:
As soon as I had the cover on the bench, and having seen photos of other pumps, I realised my mistake. The spring is held in place with a little metal cup, which is held in by a split pin. I had put the cup open-end-out, like this:
Whereas the spring should sit inside the cup, like this:
So I'd effectively compressed the spring by 3 or 4mm more than it should have been.
I've just come back from the garage having put it all together, and a quick run (after cranking with coils disconnected to prime the system) showed 80-85psi at idle on my new mechanical test gauge. So that's bang on Evoluzione's 6 bar
It still peaked at about 100 when revved but it's clearly dropped a good 30 or 40psi.So from my previous results I can surmise that it'll drop down to around 20-30 at idle when warm, which'd be about right.
So a simple build error on my part, but I think that's sorted it. Now I'm off to wash the oil out of my nasal cavity/hair/eyes/ etc.
Good, glad you got it sorted . FLA use a similar style in lots of their pumps so I figured it could have been the cause.
If your oil pressure was off the scale now just think how high it would have been in some really cold weather, it would have bypassed the filter element sending unfiltered oil around the engine. I have seen them ruptured too the pressure got so high.
. FLA use a similar style in lots of their pumps so I figured it could have been the cause.If your oil pressure was off the scale now just think how high it would have been in some really cold weather, it would have bypassed the filter element sending unfiltered oil around the engine. I have seen them ruptured too the pressure got so high.
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