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Re: Removing/Refitting gearbox with engine still in the car?
Posted: Tue Oct 05, 2010 2:20 pm
by bmcecosse
You can easily get at the relief valve without taking the engine out! Did you renew ALL the bearings - ie Mains and Big-ends ?
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Tue Oct 05, 2010 6:21 pm
by MarkyB
It may well be that some of that nasty gunk has found it's way into the oil ways.
Did you clean the wire mesh over the oil pick-up pipe?
I've heard of some quite radical ways to get it all cleaned out, replacing the oil with paraffin or diesel and running it for a few minutes spring to mind.
The proper way is to strip the whole block down and get it chemically dipped.
I'm a fan of shade tree mechanics type solutions, but you pays your money and makes your choice.
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Tue Oct 05, 2010 8:25 pm
by bmcecosse
I stripped a 1275 Ital engine I bought - the oil ran out like paraffin and black as the Ace of Spades, inside the sump was 1" thick in black sludge lying on the bottom - yet the block was spotless inside and the crank bearings were perfect!
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Wed Oct 06, 2010 10:31 am
by richie2912
I will have a go at the relief valve first then!!
I only changed the big ends and not the mains. (so it could now be warn mains)
I cleaned the wire mesh.
It is possible some of the gunk has gone through the system as it did appear again when i changed my sump gasket! The first time i removed the sump is was not far off an 1" thick!
I think i will do a full engine strip any way and get the engine dipped and cleaned properly.
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Wed Oct 06, 2010 11:00 am
by bmcecosse
Not changing the mains is the problem then- you can drop the sump and drop out the centre main cap and inspect the state of the shell and the condition of the shaft.
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Wed Oct 06, 2010 4:44 pm
by richie2912
It does now sound like the cause! Well at least stripping the engine down again is good practice!
Thanks for all your help all!!
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Fri Dec 10, 2010 9:34 am
by swithland
bmcecosse wrote:The relief valve should lift at 60/70 psi - doesn't really matter - a steady 60 psi is fine, no great advantage in having any more and it does absorb power to churn up any higher pressure. I have to say - I have never run an engine with only 20 psi....... even a rally engine that 'ran it's bearings' causing me to retire from the Mull Rally (because I knew I had to drive the car home!) could manage 40 psi even though it rattled horribly if I pressed it too hard - it was a gentle run home.
There must be something seriously amiss in an engine that can only manage 20 psi.
Im wondering if the reason ive been having all these oil leaks at the front and rear of the sump ( cork gaskets ) is high oil pressure and not the fact there was no breather pipe on the top of the rocker cover. Im going to take out the oil pressure relief valve and have a good look at it. When the engine is cold, it goes right up to 80 PSI and only comes down to 30 - 40 psi once the engine is properly hot. Maybe its a bit sticky....although it should not be since the engine was fully reconditioned 220 miles ago....
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Tue May 03, 2022 10:08 pm
by jagnut66
Hi,
Resurrecting an old post here but, as a bit of a 'post script' to it:
Elsie May recently 'lunched' her gearbox internals (witness bits of cog dropping to the bottom of the bucket when I drained said offending gearbox), so I thought I'd try this oft mentioned method of Morris Minor gearbox removal.......
I have to say I think it is an overstated pain in the a**e!
In the end I used my engine crane to lift the engine off it's mounting rubbers, so that I could then drop it low enough to clear the steering rack and reattach my replacement gearbox from underneath.
Next time I shall stick to the tried and tested method of rad out, bumper / grill panel off and engine, with the gearbox still attached, lifted out 'as one' through the front of the car.
Much simpler, provides all round access, and, as it turns out, even though I will need to undo and remove a few more ancillaries, probably no more time consuming....... 
I may even swear less whilst doing it! 
Best wishes,
Mike.
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Wed May 04, 2022 5:47 pm
by kevin s
I think it depends on the facilities you have, 2 of us swapped the box from underneath in around 2 hours using our 4 post lift, I wouldn't want to try it on my back on the floor though.
Re: Removing/Refitting gearbox with engine still in the car?
Posted: Fri May 06, 2022 6:10 pm
by JOWETTJAVELIN