You are not logged in.
Pages: 1
ronald walker
Aug 5, 2009 - 9:32PM
A Good engineer
Hi Graham
Thanks for your diagnoses,i have just changed the oil so your probably right and i wont have any talk of you not being an engineer,i rebuilt a bmc diesel years ago when i was young & fit and yet i could not fathom out what was causing the pressure dip,thanks again for your invaluble help.Ronnie.
SeaDog Name (if owner or crew) kushka
Email
Eric Richardson
Aug 6, 2009 - 9:11AM
Re: A Good engineer
Hi Ronald
I had replied to your question before reading thje next bit.
When the Perkins get a bit long in the tooth wear in the oilpump allows it to drain if the filter is remove or the engine stood for a long period and they can take a while to prime up.
I remember Peter having this problem and I made him a priming kit to get going.
Eric
Alan and Deb
Aug 6, 2009 - 5:06PM
Re: A Good engineer
We have a similar issue. Star Dog's oil pressure (Perkins 4107 in good nick)is good in normal use, goes straight up to 50 - 60 PSI and does not fluctuate. But -- after an oil change it takes what seems to be an age to regain any oil pressure on first start up. We have done three oil changes now and have tried all the usual tricks, filling the filter etc but it still rattles like a banshee on first start up. I actually timed it last time and it took about 40 seconds to get up to pressure and stop rattling, not so long I suppose but it upsets my sensibilities. Should we be doing anything else?
SeaDog Name (if owner or crew) Star Dog
Eric Richardson
Aug 7, 2009 - 10:25AM
Re: A Good engineer
Hi Alan
On the basis that you change your oil regularly try this next time.
First give the engine a run to warm it up and change the oil, trying to do it reasonably quickly and start the engine as soon as the sump is full.
Allow it to cool down then just run it for a short period and change the oil filter starting up again as soon as possible.
The problem is wear in the oil pump which allows the system to drain down. The filter tends to prevent air getting in above the pump and holds some oil back to help it prime on start up. if the oil is cold when the filter is changed it drains a bit slower.
I have known these engines to fail to prime completely after a long lay up and need priming. If your filter is the type which screws on from above it is worth fitting the non return valve version of the filter it helps maintain a vacuum.
Eric
Alan and Deb
Aug 7, 2009 - 11:43AM
Re: A Good engineer
Thanks Eric I'll follow your advice next oil change and let you know how we get on. Hope you are well.
SeaDog Name (if owner or crew) Star Dog
Offline
Pages: 1