Oil Pressure - Variable (Tick Over speed)

I'm going to start a couple of tech threads s that each of the problems has it's own title, an may be of use to others.

I've been out of doing any motor mechanicing for a long time, and was never really vey hot on diagnostics - (I used to rely on my dad for that sort of thing, but don't live within such easy reach these days.)

Anyway. on the trip back I noticed that whn the engine went from regular running to tick over, the oil pressure dropped way down. Is this as it should be please, or do I need to look at the oil pump, filter etc? - anything else I need to check t see if thereis a problem. Also, after the long run she wa reluctant to tick over well, I wonder about tweaking the carb to get a slightly higher tick over speed.

Yep, that's normal!

Sounds normal but to satisfy my curiousity what did the pressure drop down to?

20lbs would be ok, less than 10 and I'd probably be slightly concerned. Although saying that mine never much got above 20lbs on a run (when warmed right up) and dropped to near zero at idle but it ran great up to the day I've taken it off the road for the body work etc to be done.

Maybe a better gauge would be how hot was the water temp? If that's highish then the oil pressure will be lower than it should as the oil thins right down.

Zef wrote:Sounds normal but to satisfy my curiousity what did the pressure drop down to?

20lbs would be ok, less than 10 and I'd probably be slightly concerned. Although saying that mine never much got above 20lbs on a run (when warmed right up) and dropped to near zero at idle but it ran great up to the day I've taken it off the road for the body work etc to be done.

Maybe a better gauge would be how hot was the water temp? If that's highish then the oil pressure will be lower than it should as the oil thins right down.

During normal driving conditions oil pressure was around the 50 but up to 75 mark, but then dropped down to below the 20 mark on tick-over, probably down near where 10-15 would be. i have to admit I didn't monitor the water temp, but thsi was only on a shortish rn of 15 miles or so.

I'll start to keep a record of guage readings and fuel consumption anyway, as it's probably a good guide to keep going.

50 to 75 psi is spot on. 10 to 15 isn't too bad.

You could always pop the rocker cover off after a run and make sure you see oil seeping along the rocker shaft. If it's there at tick over after a run then I don't think you have much of a problem.

I would also double check the oil level, and make sure your using the correct oil! Millers Trans M is good, but I also hear the valvoline stuff is good - but make sure you only use a basic oild - no fancy synthetic stuff.

What kind of oil do You use? Some minerals are very sensitive on temperature. I have experienced some of them dropping more pressure hot then others.

I bought some "Classic Car oil" from Quality Factor in Chester for £14.34 + VAT (should have been £19.29+ VAT) and the filter £1.43 +Vat (should have been £2.85 + VAT)
Pressure on start up was nil as you would expect and within about 30 seconds it reached around 60 .I have used this for the last 12 months no problem.
If you can, get some Morris's oil, it,s been produced for worn engines but I have'nt found a local supplier.

When hot it read about 30 on tick over (and 1 pint short too!)

I've started using Miller's Classic Mini Engine oil - supposed to work as a 20/50 for cars using the oil also as a gearbox lubricant:::

http://www.millersoils.net/1_Millers_frame_CLASSIC.htm

...find Classic Mini Oil on the next page (click on Engine Oils)

I'm at about 40 psi on tickover (hot) after about 12,000 miles since rebuild.

So far, I'm happy with it

Cheers

It is worth checking the oil pressure regulator valve. They can seize hot, thus oil pressure can drop on idle.

Also change the oild very regularly, I do every 1500 miles in my Mini, and use the Morris or TansM - oil can make a massive difference as others have said. Zero at start-up isnt good, crank it over without the plug caps on to get oil flowing.

superworm wrote:I've started using Miller's Classic Mini Engine oil - supposed to work as a 20/50 for cars using the oil also as a gearbox lubricant:::

http://www.millersoils.net/1_Millers_frame_CLASSIC.htm

...find Classic Mini Oil on the next page (click on Engine Oils)

I'm at about 40 psi on tickover (hot) after about 12,000 miles since rebuild.

So far, I'm happy with it

Cheers

Chatting to Keith Calver today at the Mini fest.Uttoxeter he swears Miller's is the best for mini engines. The classic oil I mentioned earlier in this thread is rubbish and cannot take the thrashing of the gear box when hot.My pressure dropped alarmingly to a max of 30 at 70mph on motorway!
I have Comma in at the mo and that gave a preesure of 50 at 70mph on way to the show so a little improvement!

Sorry for the non-response everybody. Had trouble getting online and forgot my password etc. etc.

I have made a note of some of these comments / suggestions and will try out soem bits and bobs. Everything seems to be running OK though

It's just standard oil in it, so when I do a service and change the oil I'll try one of those suggested. I've found she runs a bit better when I put in a bit of lead subsitute with the petrol.