oil leak front of 1098 engine

[estepona1999]

I have a rebuilt (by a member) 1098 engine and I have quite an oil leak from the front of the engine.It appears to be coming from the bottom of the timing chain cover,is this a common leak area or am I looking at the wrong thing? the engine was stood for about 4 years without any oil in it,if that has any relevance,could a seal be faulty without oil? I hope it isn't an engine out job.Help please

[Budgie]

If it hasn't had oil near it for some time then seals / gaskets can dry up and shrink which can lead to oil leak issues any where there is oil to be held back.

[Chipper]

Yes, they can sometimes develop leaks. Have you tried tightening all the little bolts (7/16", IIRC) around the timing chain cover evenly first?

The timing chain cover is fairly easily removed without having to take the engine out, though of course, the crank pulley/large nut needs to be undone and they are usually pretty tight!

You may wish to uprate to a quieter, more durable Duplex (twin) timing chain - kits are available from numerous Minor specialists.

[estepona1999]

Thanks to you both.if an oil seal has shrunk would it swell up once oil has leaked from it or is it too late? Also the timing chain was apparently upgraded to the duplex type,is there an oil seal under the timing cover or is it meant to have oil in there? I will try the bolts tomorrow and see if I can tweek them a bit tighter.

[simmitc]

There are three possible issues: (a) gasket between timing c0ver and block (b) oil seal around crankshaft pulley (c) crankshaft pulley work so that the seal cannot seat - seals will eventually wear grooves on the surfaces on which they run. You could add (d) any combination of a-c.

To make remedial work simpler, remove the front panel and radiator completely. This gives excellent access to the work area. The pulley should be fitted with a lock tab. Once that has been unlocked, fit the correct size socket and undo the retaining nut - if it has provision for a starting handle (which it should) then you will need a deep socket. It will require a lot of effort to remove the nut. Search on here for more tips in that matter. Wit the nut off, the pulley "should" come off easily. Inspect the shaft for wear and renew whole if required. Remove the bolts from the timing cover (loosen opposite bolts to avoid distorting the cover. With the cover off, remove the old oil seal and fit a new one - it presses out and in using a drift. Make sure that all surfaces are clean prior to reassembly. Refit the cover using a new gasket. Loosely fit the pulley to ensure that you get the cover with the seal central to the shaft. Tighten all bolts a little at a time, working on oppoosites, to avoid distortion.

With the cpver on tight, fix the pulley in place, remembering to use a new lock tab.

If you need a new pulley,, then the solid ones from Birmingham are far better than the rivetted ones.

[philthehill]

Oil leaking from the gasket between the timing cover and the front engine plate is a common problem.
BMC/BL fitted a stiffening plate to the lower front of the timing cover Pt No: 12A666 to try and overcome the oil leak problem.
You indicate that the engine has been fitted with the duplex set up. Engine oil can leak from between the front engine plate and the block in the area of the two 1/4" UNF countersink screws if the screws have not been fully tightened or Loctited in place. Allen headed screws are the best for this application.
As regards leaks at the pulley /timing chain cover oil seal - possible problems & solutions have been outlined above.
The oil thrower plate must be the flat type when the duplex set up is fitted and not the cupped typed as used with the earlier timing chain cover.