Timing Cover/Back Plate Gap

[AlfaLofa]

Can some one tell me how much "give" there is in the front cover and its back plate?

Neither seem to be flat - and when placed against each other they can be rocked.

Tightening the bolts should close the gaps (with sealant) - but is this normal?

(I've also made a set of gaskets which I intend to use).

[AHM]

Not much movement in the front cover - check for burrs from chisels and screwdrivers.

The backplate is easily bent when pulling the front cover off - usually radiates from the single retaining screw. It is possible with a pess and some patience, to get it flat.

Don't forget that the backplate seals oil and water and has a large sealing area with the block.

If you get it to fit the front cover correctly you won't need a gasket, and more importantly it is less likely to leak.

[avro]

Hi Steve
I would agree with the previous post and say that it's not likely the front housing is distorted. The back plate however can easily be bent out of shape. The area around the pump itself can be quite difficult to prise apart especially if the previous builder has used certain types of sealant. Unfortunately during the life of the engine someone has been a little heavy handed in trying to prise the two halves apart from the outside edges. Its always better to place an angled pry bar down the inside from the top and closest to the pump. The back plate is supported by the block when you try to lever them apart.
I have found that the back plate can be quite easy to straighten by simply placing it on the edge of a workbench and pressing down with the palms of your hands on the outer edges. A little bit of applied body weight in careful stages usually does the trick if distortion is not too severe.
Many years ago some gasket sets were available that included a pair of suitable gaskets but I have always found that using a clear RTV sealant much better. Any slight localised distortion or minor damage to the mating surfaces is taken up by the sealant and fortunately there are quite a number of nuts and bolts that hold the two halves. together.

Cheers

Nick

[AlfaLofa]

AHM and Nick - Thanks for your replies.

I didn't deform the back plate - but I'll have a go at straightening it.

The plate deviates from true for about 3 inches on the top edge (where it's not in contact with the block).

The photo shows the gap - even the bend is (I think) just about visible !!!