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MG MGB Technical - How long will an engine run?

Without oil in it?
I estimate my 'B' ran for 3-4 miles after the oil filter fell off.[blush]
[never buy a cheap part]
I looked at the one remaining oil filter of the same brand, and the threads are pathetic.
Me, the guy that always says, 'Ya gets whatcha pay fer'

Well the crankshaft is back, and the block.
The crank polished out to where it had been turned 3 years ago.
.010"! [under]
And the block honed out at the .040" where it had been bored to.
Number 3 piston wrist pin seized and consequently scuffed the piston, and the cylinder wall, But it honed out!
Whew!
Sigh of relief.
Rod bearings were sorta chipped, but never spun, and everything else looks OK. But I will clean everything up, and put it back together.

Has anyone else have a similar experience?
Safety Fast
Dwight

Dwight

You were lucky there Dwight hope everything goes according to plan. I had 5 miles in my mind and you have sort of confirmed that. However it would seem that 2 miles might not have resulted in any damage. During that two miles there would have been zero oil pressure but the film of oil kept the surfaces apart even under driving conditions. This must give us all comfort that the first few seconds when we start our motors is not as critical as some make out even on a new engine and provided that the surfaces are well lubricated. The revs should obviously be kept to a minimum until the pressure rises.
Iain MacKintosh

Didn't your oil pressure drop?are you saying you can drive without knowing the filter is gone for 3 miles?If this is the case how can we know if we have a problem?
What were the symptoms? Did the car just quit? Any noises?I am always scanning my guages when I drive my B and if the oil pressure gauge won't respond to a loss of oil This is not good.
Pat in Tehachapi
patrick bailey

What was the name of the cheap oil filter? This info might prevent another from having the same experience.
Lewis

Glad to hear the damage was repairable. I've seen TV shows where at some auto type events they take a junk car, remove the coolant and oil and put a brick on the accelerator and guess how long it will run before it blows up. Surprising how much abuse some engines will take before siezing.
Bill Young

Hi all.

I must admit that I don't look at the oil pressure gauge often, and look at the temp gauge fairly infrequently unless I am stuck in traffic.

It would be relatively easy to install an oil pressure warning switch connected to an audible alarm that would sound if the oil pressure dropped.
It would sound when the ignition was turned on but the engine had not yet built oil pressure, but I guess that might be acceptable.

A high coolant temperature alarm would not be too difficult.

But then.. I like my BGT because it is free of complex electrics..

Don
Don

Dwight, when I worked at a shop in Duluth, one of the guys forgot to add oil after an oil change. The owner not only left with his van devoid of oil, but he drove 10 minutes before he saw there was no oil pressure. Then he drove it back to the shop empty - probably a total of 10 miles! The tech added oil, ran it a few minutes, and changed the oil again. It ran fine, and the owner was instructed to have his van towed back to our shop if it blew, and we'd fix it. I worked there two more years and never heard from him! Maybe he sold it?
Jeff Schlemmer

Then there are those commercials on TV (actually have not seen one for a while) Where they used to drain the oil out and then run the engine to show how well their product worked.
Bruce Cunha

I have a '91 Plymouth Voyager 3.0 Mitsubishi. Almost 250,000 miles. A couple of years ago, my wife and I took off on a trip of about 80 miles in 0 degree F weather. Dangerously cold, not weather you want to stay out in for long. About 20 miles into the trip, I said "Look, the van's smoking." We were putting a pretty good cloud out the back. About 10 miles farther, wasn't smart enough to stop in the next town, the oil light came on solid. 10 miles to the next burg, only a bar and a few houses, really. Stopped at the bar and begged for a quart of oil, a friendly man gave me one. I put it in, started back up, and drove to the next town and bought a gallon of oil. Filled the sump, and never had any more problems.

The concensus of mechanics was that the PCV froze and sucked out all the oil. The clearances on this engine had been loose for a while, in the summer the oil light will flicker at idle when hot. Since that cold day, I've been ready to hear death noises from the old girl, but the worst I can get her to do is smoke at hot idle from what I assume is worn valve stem seals. And it doesn't even do that if it's driven on the highway enough to keep the majority of oil burned off the converter. It still uses very little oil, I don't think I damaged her at all that cold day.
Tom

I was at a hill-climb watching a highly tuned Scimitar GTE roar off from the line and wondered what the big orange light (a Mini indicator unit) on top of his dash signified, then noticed the large and spreading pool of oil at the start line! He got several hundred yards at least at full chat before he noticed or was flagged down (it was out of my sight). Apparently his oil filter had come off, but fitting a new one and filling up with oil and given another go he still won his class.

It's what I've always said - gauges are more something to worry about than a useful indication of a sudden problem, and sometimes not even a developing problem. I had a hose pin-hole on my V8 and only noticed because it was spraying on the HT leads and causing a slight misfire when accelerating, the oil pressure and water temp gauges were absolutely normal. MG only fitted oil coolers because people were complaining about low oil pressure in summer traffic. On modern cars including the RV8 - which didn't even have an oil pressure gauge - the temp gauge is linked to the ECU which keeps it on the 'N' through the normal variations of temperature as the electric cooling fans cycle on and off - absolutely pointless. Far better to provide and audible and visual warning of an actual problem.
Paul Hunt 2

Questions, questions. Well lemme see here...............

From; "patrick bailey, California, USA, pbailey6000@earthlink.net
Didn't your oil pressure drop?are you saying you can drive without knowing the filter is gone for 3 miles?If this is the case how can we know if we have a problem?
What were the symptoms? Did the car just quit? Any noises? I am always scanning my guages when I drive my B and if the oil pressure gauge won't respond to a loss of oil This is not good.
Pat in Tehachapi"

My answer; I was driving home from a club meeting, with a fellow club member along. It was dark, and late [for me]. the guage was fine when we left. and I didn't look until there was a power loss. The only noise was like a small pinging, which went away when I accelerated. After I got it home, then with oil in it, it had a rapping sound.
AND I always scan my guages as well, but this time, just tooling down 35E, [the practice highway] I wasn't 'taying appention'


From; Posted 06 January 2006 at 16:20:10 UK time
Lewis
What was the name of the cheap oil filter? This info might prevent another from having the same experience.

My answer; Pro-Tech from Bumper to bumper APS.

It is my fault, as I always say, 'The bitterness of poor quality, remains long after the sweetness of low price is forgotten'

Or,' ya getz whacha pays fer'

Now it will only be Amsoil, Hastings or Wix filters!
http://www.amsoil.com/products/ea_filters/EaO.aspx

Safety Fast
Dwight
P.S. Don't you just love the way I slaughter the Kings English?
Dwight

NO?
YOu don't like that?

SF
Dwight
Dwight

You know how a MGB with the upside down filter knocks until it gets oil?
That's what I would expect, but did not get.
I've been advised to install a ignition cutout switch, that would shut the ignition off when oil poressure drops. However, this was/is an abberation!
It would also make it slower starting, until pressure built up.
Good or bad?
SF
Dwight
Dwight

I wouldn't fancy the ignition cut-off idea personally - for instance, imagine you were on a busy multi-lane main road and for some reason your oil pressure fell off. Would you rather be able to drive to the hard shoulder and avoid the rest of the fast moving traffic around you (keeping in mind that the engine will probably be fine with zero pressure for the minute or so this might take) or end up with no engine, no servo assistance on the brakes (if you have a servo fitted) and be stuck in the fast lane?

Just my 2 pennies worth!

Tim.
Tim Jenner

Years ago when Mini racing was all the rage oil pressure was a real concern and the pumps which were mounted at the rear of the camshaft seemed to be of dubious quality. The way round this was to fit a large oil pressure warning light so that if the pressure dropped below the switch setting of 5 - 7psi the light would come on. Commonly we used a front indicator light for this and with a thing this size on the das there was no way it could be missed.
Iain MacKintosh

"there was no way it could be missed"

Depends on who is looking and what they are concentrating on! See my post of 7th Jan.
Paul Hunt 2

Also you already have an ignition switch for oil failure while underway - as long as you don't turn it too far and lock the steering as well. Ignition cut-off switches have been used to allow the engine to crank until oil pressure is raised before you allow it to fire.
Paul Hunt 2

Oops, forgot about that one. Don't know there's much more we can do. There's a few well known sayings I could insert here but will refrain !!
Iain MacKintosh

Paul, quit pickin' on Iain.
Sometimes you need to keep your eyes on the road.
'Specially when you are in competition.
Iain, tell me more about the Highlands. My Dad said that's where our family came form a coupla hunert years ago.................
You really have the steering wheel on the right side of the car?
LOL
SF
Dwight
Dwight

Yes, we do have the steering wheel on the right side of the car, it was uppity colonials who insisted on having it on the wrong side ...
Paul Hunt 2

Dwight, where about in the Highlands did your parents come from.

What I was going to say was that we can cater for fools but not damn fools and I wonder if we can ever come up with something foolproof.

Paul's fine and a wealth of knowledge as we all know. I believe that it is this sort of healthy banter that keeps this board alive.
Iain MacKintosh

Dwight, have a look at this http://www.visithighlands.com/ and enjoy. We have very close friends in Stourbridge, West Midlands not very far from Paul and they come frequently to the Highlands and enjoy it greatly. In fact they moved here for 15 years and didn't want to go back to the Black Country. Paul, you might like it too. We have many very active classic circles. In defence of the Midlands there are also some very attractive areas in close proximity.
Iain MacKintosh

Instead of running a switched ignition through the oil pressure switch, try switching the fuel pump as many newer computer controlled cars. Make sure to install a bypass to enable the pump if the float bowls are dry, but usually this would save the engine as well as give you some way to move the car off to the side of the road in the event of a failure. An additional feature is that in the event of an accident where the engine is stopped the fuel pump won't continue to pump fuel which could add to a potential fire hazard.
Bill Young

Stourbridge isn't in the Black Country :o) Love Scotland for its scenery, traffic free roads, Isle of Jura malt, but would rather move somewhere with more summer than Solihull rather than more winter. The Midlands is a big area, and does have some beautiful areas: I love Shropshire for its unspoilt (with the exception of Telford) character, Worcestershire and Herefordshire and the borders of Wales. But the New Forest takes some beating. Don't like Solihull, never have, lived here 30 years. Work and childrens education commitments kept me here most of the time, now daughter and two grand-children I would hate to move away from, son and potentially more grandchildren are already further than I would like.

If you did use an oil pressure switch you would either have to isolate it from ground or use it to operate a relay. In the former case at least you would also have to use the special oil switch which is part of the North American anti-runon valve circuit and not the more usual 'low oil pressure' warning light switch as you need a switch that *closes* when you have oil pressure. Anything that switches the fuel pump off is unlikely to have any effect other than in the very rare, and usually only after working on them, occasions when the float bowls are empty. Far better to have a manual switch in the ignition if you really want one - less to go wrong, and you are in control.
Paul Hunt 2

Iain, I have no idea. The oldest thing I know, is my great grandfather fought in the cival war. And yes he fought for the union!
Oops!
Now the Johnny Reb's are gonna get all up in the air.

Paul, who you callin' an 'Uppity colonial'?
And don't you dare call me a 'Yankee'
They are only from Vermont, and eat pie for breakfast on Thursdays.

I'll take a look at that site Iain, thanks.
gotta admit you'all, the Brits mad a car that sure has left an impression.
Even my son Brian is addicted.
Bill, I want the engine to turn off immediately, and not wait for it to run out of fuel.
But I think I will be way more dilligent in watching my oil pressure guage, and what oil filter I use, and how often I will check the oil filter, and so on and so on........
SF
Dwight

Dwight

Iain, I have no idea. The oldest thing I know, is my great grandfather fought in the civil war. And yes he fought for the union!
Oops!
Now the Johnny Reb's are gonna get all up in the air.

Paul, who you callin' an 'Uppity colonial'?
And don't you dare call me a 'Yankee'
They are only from Vermont, and eat pie for breakfast on Thursdays.

I'll take a look at that site Iain, thanks.
gotta admit you'all, the Brits made a car that sure has left an impression.
Even my son Brian is addicted.

Bill, I want the engine to turn off immediately, and not wait for it to run out of fuel.
But I think I will be way more dilligent in watching my oil pressure guage, and what oil filter I use, and how often I will check the oil filter, and so on and so on........
SF
Dwight

Dwight

This thread was discussed between 06/01/2006 and 22/01/2006

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