3 replies to this topic

[classicoop]

I think my main seal and/or timing cover is leaking. Got a couple of questions.

 

1. What's the size of the front main seal (timing cover seal) for a 1991 1275? Plan to get one locally.

2. Possible not to use a gasket and simply use RTV sealant instead?

3. Will the engine mount need to be removed? (I've read some remove some don't, which is it?)

 

Also what's the difference with the Minispares LUF10006 (1992+ / Viton) and 88G561 (Pre 1992)? They both say fits all a-series. Is the 1992+ simply an updated part (Viton)?

 

 

[Cooperman]

Do you mean the timing cover seal or the timing cover gasket?

The seal is a standard design lip seal for sealing where the front pulley passes through the timing cover.

The gasket fits between the timing cover mounting face and the engine front plate.

In both cases the correct seal or gasket is necessary.

However, the front main seal, which you also mention is the 1/2 moon shaped seal which is fitted behind the engine front plate and is squashed between front main bearing cap and the gearbox front lip.

Edited by Cooperman, 17 June 2013 - 05:28 PM.

[classicoop]

Part 10 - What's the size? (id / od / width)

Part 11 - Can I just use sealant and do away with the gasket?

 

Edit:

The half moon you mentioned, does it cause oil leaks also? I'm not entirely sure where the oil leak's coming from. The whole engine radiator side (below the pulley) to the oil pan(?) to the entire floor is wet with oil, even the gear linkage is wet. Probably just oil splattering from where ever it's dripping.

 

 10 11 .jpg   42.81K   6 downloads

Edited by classicoop, 18 June 2013 - 03:22 AM.

[tiger99]

There is a lot more to selecting an oil seal than just the diameter and width. There are very many variants of material, spring tension, etc, and many of those available are not suitable for car engines. If in the slightest doubt, buy the correct part, which is not all that expensive.

 

Usually the timing cover is a bit distorted and it is advisable to use some kind of sealant such as Red Hermetite on the gasket. RTV on its own is best avoided, as you would need a thick bead of it in that particular place, and some would most likely get inside the timing cover, fall off and get chewed by the chain. RTV seems a nice soft material, but like all silicones, it can block oilways, and if it migrates to the hot parts of the engine, degrades into silica, basically sand, which you don't want in there. RTV is great where there is no risk of it going astray.

 

The half moon seal may occasionally leak, but most of the time it is because it was fitted without a small blob of RTV between each of its ends and the sump gaskets, which overlap it. You also need a small blob of RTV at the other end, where the sump gaskets butt up against the transfer case gasket. Some people put a thin bead of RTV in its groove, but it rarely leaks around the edge so that is not necessary, and as said above, you don't want stray RTV inside. Changing the half moon seal means splitting the engine and gearbox.