engine question

[gtr-gaz]

I need to change the rear crankshaft oil seal on my AS engine. If I have the engine upside down to remove the crankshaft, do I have to worry about the pistons dropping onto the valves? I can just imagine the piston rings popping out the bores!!

BTW, I e-mailed Gail last week about the type of rear main seal they use. They have switched to Fel Pro 40013 and they have proved much better!
Hopefully the newer AS engines will be less prone to oil leaks than mine. Mine has also been leaking from the sump gasket and the rocker covers. Not much, but enough to be noticable.
It's obvious once the engines out, but trying to locate them with the engine in is almost impossible!

Gary

[steve_d]

When upside down the pistons could, when released from the crank, slide down and sit on the valves. The rings cannot escape in this position but would if you pulled the conrod towards you so the piston came out of the bottom of the bore. You will no doubt be careful with the rods so the piston will not just drop onto the valves so there is no risk of damage. Take care not to let a rod fall over to the side as it could knock a lump out of the bottom skirt of the bore or put a dink in the rod. The dink would then become what is known as a 'stress riser' and cause the rod to stress fracture at that point.

If you are just going to replace the seal you may be able to do this without removing the bigends. Just release the main bearings and lift the crank enough to slip the new seal in.

Steve

[gtr-gaz]

steve_d said:

If you are just going to replace the seal you may be able to do this without removing the bigends. Just release the main bearings and lift the crank enough to slip the new seal in. Steve

Thanks for the advice Steve. I did think on doing this, but according to my book on how to rebuild a SBC, it says to use some silicone sealer as well, so not sure how much I will need to lift it. I shall certainly try that to start with. Cheers.

[Boosted Ls1]

gtr-gaz said:

steve_d said: If you are just going to replace the seal you may be able to do this without removing the bigends. Just release the main bearings and lift the crank enough to slip the new seal in. Steve Thanks for the advice Steve. I did think on doing this, but according to my book on how to rebuild a SBC, it says to use some silicone sealer as well, so not sure how much I will need to lift it. I shall certainly try that to start with. Cheers.

Remove the rear cap and the sealant goes on the lengthways part of the block inboard of the seal. If in doubt I doubt you could overdo it. Loctite make some really good anerobic sealants for jobs like this.

Boosted.

[pb3]

I was wondering as you seem to have oil leaking from all the places it shouldn't that you may have a crankcase pressurisation problem. I would like to think that the sump gasket was well sealed, mine had the addition of silicon sealant, which I think is a standard method. Also unless the rocker covers are not tightened down or the gaskets are damaged I would not expect them to pass any oil or perhaps just a tad.

When I suffered my problem with my front oil seal failure I felt it necessary to add an additional crankcase breather as did tuxman under his engine builders recommendation. It may be worth a chat with you newly appointed engine builder.

[steve_d]

I fitted a PCV valve to my engine which cured all my oil leaks.

Steve