NL oil pressure

[kmacdonald]

Yes a64Pilot, that about sums it up. The Kubota problem I mentioned was a small tractor with 5 psi oil pressure. It was run for a while with no catastrophic damage. I personally wouldn't run it like that for long since it surly has long term consequences if not repaired. I wouldn't expect any damage was done to the OP's engine.

[Compass790]

Don't need to run it, spin it up decompressed as Wottie suggested should do it. Hope for OP's sake it is just loose rocker arm mount.
Yes sounds like he will escape any damage. Been an interesting thread & good inputs from the hive.
Forgot to say if OP uses air to trace leak put rags over head for initial blast as galleries will have some oil in them.
Gagging to know what it is but certainly sounds like skipperpete & DougR on the right track or maybe kmacdonald if his rocker arm has plugs in it.

[Olly75]

Well...

As an update, yes Im an idiot!

Took the valve cover off again and lo and behold the first nut holding the rocker arm in place was only finger tight. So tightened it up, checked the others (which were fine) and started her up and now have an oil pressure of about 47psi. I think somone said it should be around 60psi, but Im assuming 47 is acceptable?

Either way, phew what a result, and what an amazing forum!

In future, assuming I ever attempt to check valves again, i will always check the nuts holding the rocker are in place.

[Compass790]

Great result!
Look on the bright side you didn't have to take the oil pump out or spend a fortune.
47lb is heaps. Plenty of farm tractors go for years at only 20lb oil pressure

[a64pilot]

Originally Posted by Olly75

Well...

As an update, yes Im an idiot!

Took the valve cover off again and lo and behold the first nut holding the rocker arm in place was only finger tight. So tightened it up, checked the others (which were fine) and started her up and now have an oil pressure of about 47psi. I think somone said it should be around 60psi, but Im assuming 47 is acceptable?

Either way, phew what a result, and what an amazing forum!

In future, assuming I ever attempt to check valves again, i will always check the nuts holding the rocker are in place.

60 something Is my motor, and motors will differ. Look up the specs but bet 47 is fine, especially if it stays at 47 when it’s hot.
Being as it was cold that probably means that the cold oil relief valve is set at 47 PSI.
Let her run until it’s at normal operating temp and see what the pressure is, that’s the real test actually a hot idle is, but generators don’t idle so don’t worry about it.

Really glad to hear it was a simple fix.

[a64pilot]

Oh,, and sorry to bring what could be bad news, but if you adjusted valves with the rocker shaft loose, that may mean they are too tight, so now you get check them again, cause a little loose won’t hurt, but too tight might as they can leak and burn, plus valves wear tight so you don’t want to start tight.

[kmacdonald]

Originally Posted by a64pilot

Oh,, and sorry to bring what could be bad news, but if you adjusted valves with the rocker shaft loose, that may mean they are too tight, so now you get check them again, cause a little loose won’t hurt, but too tight might as they can leak and burn, plus valves wear tight so you don’t want to start tight.

Yes, good advice. You might want to replace the gasket also. It could be leaking slightly and decreasing the pressure. Glad it wasn't a big deal and you got it fixed.

[skipperpete]

Nice work olly75[emoji106]. Make damn sure that the rocker cover gasket seals perfectly or else you’ll be wondering why the oil consumption is excessive, that skinny bit in the middle is critical.

[Wotname]

Originally Posted by Olly75

Well...

As an update, yes Im an idiot!

Took the valve cover off again and lo and behold the first nut holding the rocker arm in place was only finger tight. So tightened it up, checked the others (which were fine) and started her up and now have an oil pressure of about 47psi. I think somone said it should be around 60psi, but Im assuming 47 is acceptable?

Either way, phew what a result, and what an amazing forum!

In future, assuming I ever attempt to check valves again, i will always check the nuts holding the rocker are in place.

Great result, good work Olly75 . You fixed it and learn new skills in the process. If it makes you feel better, I once had a new Yanmar that had a loose rocker arm support straight from the factory!

Great analysis by skipperpete, DougR and others

interesting thread and I sure many readers who haven't posted in it have learnt good stuff from following it.

[kmacdonald]

Originally Posted by Wotname

Great result, good work Olly75 . You fixed it and learn new skills in the process. If it makes you feel better, I once had a new Yanmar that had a loose rocker arm support straight from the factory!

Great analysis by skipperpete, DougR and others

interesting thread and I sure many readers who haven't posted in it have learnt good stuff from following it.

And it only took 8 pages. Some of the anchor threads go for hundreds of pages and they still haven't figured it out.🤩

[Wotname]

Originally Posted by kmacdonald

And it only took 8 pages. Some of the anchor threads go for hundreds of pages and they still haven't figured it out.🤩

Prolly only 1.5 pages of real analysis and diagnostics and 6.5 pages of chatter between the punters

[kmacdonald]

Originally Posted by Wotname

Prolly only 1.5 pages of real analysis and diagnostics and 6.5 pages of chatter between the punters

Agreed.

[Olly75]

The gaskets not in mint condition by any stretch, so I've got one on order.

I'll think about adjusting the valves in a couple of days, don't want to push my luck with it just yet!

[Compass790]

Originally Posted by Wotname

Prolly only 1.5 pages of real analysis and diagnostics and 6.5 pages of chatter between the punters

thats real analysis but the chatter between the punters is fun to read too.

[kmacdonald]

Originally Posted by Olly75

The gaskets not in mint condition by any stretch, so I've got one on order.

I'll think about adjusting the valves in a couple of days, don't want to push my luck with it just yet!

Just to be clear, I meant the gasket between the rocker arm support and head, if there is one there. If there is one its super thin, like paper or thinner.