26 replies to this topic

[SomethingNew71]

Do not strip it out until you have checked for contaminants in the oil...... 

 

Drain the oil in to a clean (only clean if you would eat off it) drain pan, then take a good look at the sludge if any in your oil if there is no silvery flecks in your oil then you have NOT destroyed your engine bearings.

 

so what is next.....  did you also notice a slight increase in the water temperature ?   when you built the engine did you get it to a rolling road ?  then you need to get it to a Mini based rolling road as I suspect you have retarded ignition.

 

However if you find lots of flecks and you didn;t get a slight increase in your water temperature then yes you will have to strip it out for a rebuild as stated above.

 

 

So when I drained the oil there were more flakes than usual on the plug for sure but I didn't see any silvery flecks.  In addition my water temp was steady 100% didn't change at all.  Unfortunately I am located in the USA and there are no mini specific rolling roads here.  In addition the dynos that are around us only understand domestic motors like mustangs and carbed motors are like Chinese to most of the shops.  

[SomethingNew71]

 

 

if it sounds bad I would say the bearings have gone.

 

need pulling.

 

I just put brand new bearings and rebuilt the motor about 11 months ago.  With the oil pressure back up now it sounds fine.  Think with the low oil it was just getting rough in there between the metals.  

 

 

"rough in there between the metals" ?  eeeeeek !  I hope it is ok, as it can be very costly if you have damaged the crank etc...

 

Oil pressure is also a function of the following..

 

Crank journal / bearing wear / damage

Camshaft journal / bearing wear / damage

Camshaft follower and their bores, damaged or worn.

Rocker shaft, rocker post, rocker damaged or worn

PRV valve and / or seat worn or damaged

 

In my opinion and experience most of the above are ignored or forgotten about during an engine rebuild.

 

 

During my rebuild I did the following:

 

• Crank going over by machine shop
• New fast road cam went in
• New thrust washers to account for a knock(slightly oversized)
• New cam bearings
• New rod bearings
• New oil pump
• Big Valve conversion
• Ported and polished head

[MRA]

Did you strip out the oil gallery plugs and brush them through ?  this is a prime area for old hardened oily deposits that will loosen during the rebore or any other machining work.

 

Also you didn't mention rockers and rocker assembly ?  although in most cases they last for years you can get wear in any of the areas I mentioned above, anywhere that oil can get past will create a lower oil pressure, but 100psi ?  tells me something was fitted incorrectly, a cam bearing the wrong way or a rocker post in the wrong order ...

[MRA]

 

Do not strip it out until you have checked for contaminants in the oil...... 

 

Drain the oil in to a clean (only clean if you would eat off it) drain pan, then take a good look at the sludge if any in your oil if there is no silvery flecks in your oil then you have NOT destroyed your engine bearings.

 

so what is next.....  did you also notice a slight increase in the water temperature ?   when you built the engine did you get it to a rolling road ?  then you need to get it to a Mini based rolling road as I suspect you have retarded ignition.

 

However if you find lots of flecks and you didn;t get a slight increase in your water temperature then yes you will have to strip it out for a rebuild as stated above.

 

 

So when I drained the oil there were more flakes than usual on the plug for sure but I didn't see any silvery flecks.  In addition my water temp was steady 100% didn't change at all.  Unfortunately I am located in the USA and there are no mini specific rolling roads here.  In addition the dynos that are around us only understand domestic motors like mustangs and carbed motors are like Chinese to most of the shops.  

 

Ok then you would need to understand what fuelling & ignition is all about, you have to be their lack of intelligence for your own good. 

 

Now whilst most deal with 3000000 bhp V8's with 20000 bhp of NOS and triple superchargers, the concept for fuelling and ignition is exactly the same !  it is no difference at all, so when they say it needs more advance then the distributor is that little thing poking out front with 5 leads instead of 9 !  but it is the same, advance / retard is the same thing, their job is to ensure your engine gets the best fuelling and spark for the point on the rev range you are testing at any one moment in time. 

 

So you will need to get plots for your optimised ignition curve by locking out the vacuum advance and manually adjusting then take a reading, this is your plot for the ignition curve.  You will now need to get a tailor made dizzy.

 

I would also suggest you take some spare needles with you and a file, battery drill and emery paper with a pot of oil to clean the emery ....  then modify the needle to get best results then measure and compare to the Burlen fuels list of needles till you get a good match.   You may need to do the whole lot again to get it running at its best.

[Dusky]

Last time I checked my mustang was a carbed car.

[MRA]

different carb Dusky.....  it is in a lot of cases familiarisation, I have known dyno operators turn cars away because they didn't know the carb/dizzy/ecu etc...  like all things it is hard to find a good one, I'm rather lucky in that I have a friend who lets me use his all singing all dancing new RR but not everyone understands fuelling and ignition.

 

It's all about maps and spiking the new setting for your 3D fuel/ign map 

[Dusky]

I wouldnt call it a domestic car tho ;)
Imho, its a good dyno operator when hé or she turns a car down, atleast they admit they cant do a good job, instead of taking your money and fetteling a bit without avhieving anything.

Im screwed ( can i use that word in this forum) around here. I can't even. Find a rr where I adjust the carb etc myself. After a cam change on that particular 67 mustang it wasnt easy to sort the mixture without one.. But now il going off topic

[Cooperman]

There are two issues here:

 

1.  Is the engine damaged by the loss of oil pressure?  I would guess that it is. It is no good looking for 'silvery flecks' on the magnetic sump plug as white metal is non-magnetic and will only be trapped (eventually) by the oil filter.

 

2.  The problem may have been caused by incorrect ignition timing or fuelling.

 

To address point 1 the ONLY safe solution is to remove and strip the engine. Once that is done we can advise on what to do next, what to measure, what needs changing and how to thoroughly clean and re-assemble correctly. There really is no alternative to doing this.

 

The second is more difficult, but not impossible, with no local facilities. A classic car can be set up to give good and reliable performance using the techniques we all had to use in the 1960's. When the original Minis were winning races and rallies there were no rolling roads and I know that I always set my cars up 'by eye & by ear'. Vizard's book gives a good guide to carb needles and the static timing can be set and the distributor swung after the engine is running, then done by road-testing and listening. You do need the correct advance-curve distributor, but help is available from the likes of Aldon Automotive. What compression ratio are you running?

[nicklouse]

I am still plumping for the engine out.

Oil pressure always less at tick over. Repeated need to clean the oil pressure relief valve. And now running rough?

But clarification as to what running rough actually is would be good.

As would what has changed/been changed from the high pressure running well to the low pressure running rough.

[greenwheels]

If you’re looking for a Min expert in the USA try Ron Graham. I think he works, or worked, for 7 Enterprises in Newport News. That's still 350 miles from you but I knew him when he was in England and can vouch for his expertise on Minis.

[Alex_B]

Why not cut open the oil filter, obviously carefully not to put any material from the cutting into the filter, then over a clean drain pan with gloves on open up the filter material and look for any shimmer or metal flecks? that will give you an idea if there is bearing damage, not conclusive as it gets to the filter after the pump but it could show something up. 

But I would agree it sounds like a good idea to pull the lump, split it from the box and check the main bearings for damage. 

[MRA]

There are two issues here:

 

1.  Is the engine damaged by the loss of oil pressure?  I would guess that it is. It is no good looking for 'silvery flecks' on the magnetic sump plug as white metal is non-magnetic and will only be trapped (eventually) by the oil filter.

 

2.  The problem may have been caused by incorrect ignition timing or fuelling.

 

To address point 1 the ONLY safe solution is to remove and strip the engine. Once that is done we can advise on what to do next, what to measure, what needs changing and how to thoroughly clean and re-assemble correctly. There really is no alternative to doing this.

 

The second is more difficult, but not impossible, with no local facilities. A classic car can be set up to give good and reliable performance using the techniques we all had to use in the 1960's. When the original Minis were winning races and rallies there were no rolling roads and I know that I always set my cars up 'by eye & by ear'. Vizard's book gives a good guide to carb needles and the static timing can be set and the distributor swung after the engine is running, then done by road-testing and listening. You do need the correct advance-curve distributor, but help is available from the likes of Aldon Automotive. What compression ratio are you running?

 

 

Totally agree Peter accept the OP didn't actually lose oil pressure totally just reduced ... or did I miss a post where he said he did lose all his oil pressure ? 

 

You can find out a lot by looking in the oil, it is one way the Royal Navy checks its engines for healthy running, by oil comparison from a known standard.

 

All I am trying to achieve is less work and expense if it can be avoided for somebody who is going to be totally annoyed and not feeling good about the whole situation.