13 replies to this topic

[snowsports1]

hi i have finished my mk1 with a completely rebuilt 850cc engine, I have noticed that once the engine is warm there is a reduction in revs when the clutch pedal is pressed, and there is oil dripping from the hole underneath the clutch housing. I don't know if the two problems are linked. clearly oil is leaking through from the engine to the clutch but I installed a new oil seal and seated it with heat resistant silicone.

 

please tell me I don't have to take the engine out!

[bpirie1000]

When you changed the seal before did you replace the clutch.... Contaminated clutch with oil will cause issues as well....

Best whip the bell housing off and have a look.....

Not easy job but easier than engine out....

[Stevie W]

Hi,

You do not need to take the engine out to change the clutch oil seal.....but the reduction of engine speed when you press the clutch pedal down is worrying.

Basically the clutch is pushing the crank against the thrust washer too hard resulting in the decreased engine speed you hear. Left like this you will quickly wear the thrust washers.

Before looking at the oil seal problem, check and if necessary adjust the clutch and see if the rev reduction problem goes away.

Cheers, Steve.

[grumpy dad]

Hi 

for the rev problem try this 

push the crankshaft pulley 

towards the clutch as hard as you can

use a piece of wood or something 

get some one to watch the pulley

start car and press the clutch 

it should move towards the rad about 3 or 4 thou

if it moves more than that 

you have problems with

to much crank end float 

and yes it is a engine out job 

sorry

[snowsports1]

Thanks it is a new clutch complete. I will try adjusting the clutch, it was adjusted as described in the Haynes manual. I am not really sure how to overcome the oil seal problem as I have only just installed a new oil seal and sealed it in. Can the oil seal be installed the wrong way round? Does it make any difference?

[snowsports1]

this engine block has been rebored and new pistons fitted, the company that did it gave me back a complete Block assembled ready. Would you expect the thrust washer to be replaced / checked when they carried out this work?

[snowsports1]

Having studied the engine diagram now can someone tell me which thrust washer is likely to be the problem? I believe the engine builder checked and replaced the thrust washers in the block but I didn't replace the c shaped one

[grumpy dad]

Hi 

yes you can put the oil seal round the wrong way 

the rule is the spring in the seal all wase faces the oil or grease

if you get it the wrong way its prittey useless  

 

the thrust washers sit either side of the crank main bearing 

Edited by grumpy dad, 02 February 2014 - 10:12 PM.

[Stiggytoo]

There are thrust washers either side of the centre main cap of the crank. 4 in total. Depending on what you paid for, I would expect these to be measured correctly and replaced. Are you sure you didn't damage the seal as it went on?

Edited by Stiggytoo, 02 February 2014 - 10:12 PM.

[tiger99]

The C shaped one is the primary gear thrust washer, and if the primary gear end float is excessive it can result in oil leakage, as can worn bushes in the primary gear. The end float is adjusted by the bronze washer behing the primary gear, and that can be pulled out, having removed the oil seal, without lifting the engine.

 

As yours is a MK 1, it may be old enough to have certain original features which did not work very well, including an oil feed to the primary gear, and an oil seal in the flywheel, which runs on the outer end of the primary gear. It should have had its oil feed blanked off way back in 1960, and Deva bushes fitted, but you never know.....

 

You should not have used silicone sealant, and if any excess got onto the crankshaft or inner face of the seal, it would cause leakage. Also, it is essential to use the special sleeve, or something similar, or a temporary wrap of plastic electrical tape, over the primary gear splines and shoulder when fitting the seal, or its inner edge will sustain damage, and will leak.

 

I would suggest, if your crankshaft end float turns out to be ok, say 3 or 4 thou,  just having the cover, flywheel and clutch off, prising out the seal (punch 2 small holes diametrically opposite, put in 2 self tappers, and pull them with pliers, if it will not move), take out the primary gear and examine its internal bushes, check it for good fit on the cranksahft and minimal endfloat. refit with a new seal, protecting it as above, and tapping it in carefully. The seal lip and spring must be on the inner side.

 

And, set up the clutch overthrow stop again, very carefully, as per the manual. It is most important, on all Minis, even the later Verto clutch models, that excessive clutch travel is prevented, as it does overload the thrust washers as has been already explained.

[Ivor Badger]

The Deva bush didn't appear till 63, which begs the question. what year and does it have the original white metal primary gear?

[snowsports1]

It had a 5 print clutch which I replaced along with the flywheel to enable a diaphragm clutch. I don't know the exact year of the engine

[snowsports1]

That's 5 spring clutch

[tiger99]

If it has the original primary gear bearings, it may be the only one left on the road! Maybe it is valuable? It will leak! They all did....

 

As Ivor Badger rightly says, you "may" be able to tell from the age of the engine, however so many Minis have had parts swapped over the years that it is difficult now.

 

Amazingly, Somerford still stock the early flywheel, but they say that the clutch has 6 springs. My oldest Mini had 6 springs, and had the Deva modification.

 

http://www.somerford...age=page&id=143