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No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 3:47 pm
by s3ndo
Hi guys,

1275 Marina engine

Was driving to work this morning, started hearing a knocking sound and then it suddenly got quite loud and I noticed I had no oil pressure. I pulled over, grabbed the oil out of my boot and went to fill it up, full of oil...

I left it where it was and walked to work. Any ideas?

Cheers

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 4:23 pm
by philthehill
1. Big ends or main bearings failed.

2. Oil pump failure leading to loss of oil pressure resulting in big end/main bearing failure.

Take the sump off and remove a big end cap and see what you find. Do the same with the centre main.

Sorry to say that the prognosis does not look good.

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 4:57 pm
by bmcecosse
Does sound like oil pump failure - assuming there isn't a massive leak... Could be broken crank - although that usually leaves 'some' oil pressure -to have absolutely none indicates a pretty drastic failure somewhere along the way. Even a stuck relief valve would leave some pressure showing... It's definitely full of 'oil' and not water with some oil floating on top...?

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 5:06 pm
by s3ndo
Well I've only gone off the dipstick. There was a level up to above the max (where I topped it up as I thought it was empty before realising). It could be water, it's currently stuck in a narrow country lane, AA will be my friend here I think. Currently on a 24 hours shift so can't get back to see it till tomorrow morning.

Big end I suppose will mean new engine?

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 6:13 pm
by s3ndo
I sneaked out of work for a quick look. It looks like it's oil in the pan, but there is a very slight bit of emulsification under the cap. Hardly anything though.

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 7:34 pm
by bmcecosse
With such a drastic drop in oil pressure - it will need a pretty major rebuild... :cry:

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 7:47 pm
by philthehill
If the crankshaft is shot there is a brand new Marina 1275cc crankshaft for sale on 'e' bay at a starting price of £175. It has already been relisted at least once so may not go for much more than the £175.
See 'e' bay ityem No: 251691308178.

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 8:28 pm
by bmcecosse
The last two I bought were only £50 each..... about 8 years ago certainly.... :roll:

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 9:07 pm
by s3ndo
Fingers crossed then :) I don't mind any expenditure tbh, just want her back to normal or better :)

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 9:28 pm
by bmcecosse
Here's the crank - but I do feel the price is a rip..... but there are no others that I can see.... http://www.ebay.co.uk/itm/NEW-MORRIS-IT ... 3a99f89492

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 9:55 pm
by s3ndo
If it's not the crank and instead something even worse, what engines could be a straightforward easy swap?

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 9:59 pm
by bmcecosse
It's highly unlikely to be a broken crank - although pretty sure it will need a regrind. This may be one of these cases where the oil pump drive shaft has spun in the rotor.... Another 1275 would be the straight swap (but I don't see any on ebay..) failing which a 948 or 1098 engine will go straight in -provided you have a Minor 4 speed gearbox ??

Re: No oil pressure and loud knocking

Posted: Mon Oct 27, 2014 10:05 pm
by s3ndo
It's a 4 speed gearbox but unsure if it's still a minor one? I don't foresee it having been changed.

Re: No oil pressure and loud knocking

Posted: Tue Oct 28, 2014 9:12 am
by s3ndo
Just an update. Sat in car waiting for aa. Thought I'd give it a quick turnover. Oil pressure is back and knocking noise nearly gone but still a little bit audible.

Re: No oil pressure and loud knocking

Posted: Tue Oct 28, 2014 10:12 am
by bmcecosse
When you say 'oil pressure is back' I assume you are reading this on a gauge - not relying on the light?? If only the light - then it simply indicates that your engine has died....it's far too late a warning of impending problems. With cold oil - the pressure will have struggled up enough to put the light out (anything from 8 to 15 psi) but that doesn't mean the problem has gone away. However - all not quite so black looking now - a crank regrind and new oil pump should see it 'good as new' in that department at least... And if you don't have an oil pressure gauge - put it top of your Santa list !

Re: No oil pressure and loud knocking

Posted: Tue Oct 28, 2014 11:07 am
by s3ndo
This is from a gauge not the light, aa turned up turned it on declared it big end failure and dropped me off at my mates garage. He's going to have a look later.

Re: No oil pressure and loud knocking

Posted: Tue Oct 28, 2014 11:33 am
by s3ndo
Phoned the girlfriend and told her the bad news to which she replied when she was using it recently it was knocking at bit at certain revs, mid range... :( why didn't she tell me!

Re: No oil pressure and loud knocking

Posted: Tue Oct 28, 2014 2:59 pm
by panky
Just a thought, does the Marina engine have a mechanical fuel pump?

Re: No oil pressure and loud knocking

Posted: Tue Oct 28, 2014 11:45 pm
by s3ndo
So I might be able to source a 1098 engine, however there are some modifications to my car eg a mg metro carb, large bore exhaust with 3 branch exhaust. I know thanks to bmcecosse that I need to check to make sure it's the original minor gearbox, will the 3 branch transfer across or will it need to be modified?

Re: No oil pressure and loud knocking

Posted: Wed Oct 29, 2014 10:36 am
by bmcecosse
You can use it all just as is. Only possible fly in the ointment would be if the gearbox and /or clutch operation have been modified away from standard.