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I thought I would share my experience on this one.

I get a few z's a year here with me with oil leaks from rear of engine and the customers believes to be rear main leaking. On inspection 9 out of ten of these cars have evidence of sump removel at some time in it's life. This is the biggest clue. These oil leaks have almost always been sump leaking at the rear. Not the rear main.

It's a very simple repair which seems to be difficult to get right by many. One of the cars into us had had 4 rear main seals fitted in a year by another z garage only to be the sump.

Anyway here is a run down of things to remember when resealing your sump to get it sealed first go. Once the sump is off clean off all old gasket paste frm sump and engine block. Replace the half moon rubbers if possible. Clean sump and block with a good solvant we use dry brake cleaner. Next key sump faces with light paper or grit pad.

Next I use light cover of blue gasket paste on each half moon then possition in place on the block ends. Next use silicone sealant to place a cover over the thin ends of each half moon as it lays flat on the block . Next the sump run a bead of silicone pea size all the way around the sump faces . Next using your finger pull the side of the bead down to the egde of the sump face on the inside egde all the way along do the same for the outside egde this should leave a neat layer of silicone with a high beaded section at the centre. Last run a very thing layer of blue sealant around the rounded sections at each sump end. Now very carfully refit the sump. Tighen each bolt up evenly . Once on Do Not Fill with oil for a couple of hours. These things should ensure a good sealed and well fitted sump .

 

DAZ

D2

Edited by Dazkent

Featured Replies

Just done this job, you can cut the end of the sealant tube in such away that you get an even spread and a high ridge in the middle, I copied it from a guy bonding a screen in :)

Silicone sealant as in bathroom stuff, I am going to do mine this week and was just going to use blue gasket paste?

  • Author

It must be automotive silicone gasket sealant.

The rule is clean and dry and care then it will all be ok. I have done 4 in as many weeks.

Iv only ever done rear main seal very very rarely. Normally the sump at fault from a previous repair.

I hope you are right about rear seals not being an issue all the time as mine has just gone in today for an inspection on where my Z has its oil leak.. I believe mine leaks only when its being driven.. She can be parked up for a whole week undriven and I never get any oil underneath on the floor.. My last oil change was end of December time and about a week back I checked my oil level in the morning and it was half filled.. Jacked the car up and found oil residue around the sump/rear main seal area but no dripping.. So there is a very slight oil leak somewhere for it to be half filled after 3 months of oil change.. So hope its the sump and not rear seal as mine's and auto and its a whole gearbox off job which can be financially disturbing a little..

Maybe the next sump o do I will do a picture walk through if any one wants.

 

That would be cool, nice one, especially illustrated clarification on "It's a very simple repair" and ""Once the sump is off for the DIY Zed owner.

 

Jeff TT

So hope its the sump and not rear seal as mine's and auto and its a whole gearbox off job which can be financially disturbing a little..

 

Don`t worry to much, removing the autobox and refitting in order to change the rear crank seal really is a much easier job than many would think, almost any garage with a ramp and even a moderate knowledge of the zed should do it in a morning so no biggy cost wise.

 

Good luck anyway

 

Jeff TT

  • Author

The point I was making about a simple repair. is that you think sealing a sump should be easy yet I see it all to aften were just simple errors creat a problem with pol leaking. Just trying to give some tips from my knowedge.

The point I was making about a simple repair. is that you think sealing a sump should be easy yet I see it all to aften were just simple errors creat a problem with pol leaking. Just trying to give some tips from my knowedge.

 

Yes thats cool as any tips are always welcome by the members so long as the job is explained clearly and in full, look forward to it.

 

Nice one.

 

Jeff

So do you think that the sumps were 1st removed because the customer or previous owner sometime ago had an oil leak and the garage resealed the sump, albeit poorly and in the belief that is what it was or are these the Z's now turning up from when Ryan aka Ztech tried doing engine rebuilds from the bottom?? :innocent:

Smithy

It must be automotive silicone gasket sealant.

The rule is clean and dry and care then it will all be ok. I have done 4 in as many weeks.

Iv only ever done rear main seal very very rarely. Normally the sump at fault from a previous repair.

 

i totally agree mate,i(in my time )have been to so many garages with so called experts, who seem to hype up a job just to make a few extra bobs when all it really is is a more straight forward job, keep up the good work mate, was it 11 zeds you had in just last week, bugger, keeping the dream alive eh.:rockon::clap:

  • Author

It's not know were these dumps were first removed. I wouldn't think due to oil leaks more like engine builds and big bearing jobs. Sump done years ago even in japan maybe . Bit they don't leak from Nissan from new I can tell you that . Iv been with these cars from new and see it this way. Hope that helps

daz

D2

dont forget another source of oil leaks that could be miss read as a sump/rear main leak is the VVT solenoids, again, an easy fix when resealing the rockers :)

Sorry for spelling I'm on my bloody I phone lol

 

Lol I know what you mean there, used my iPhone to send baz a pm and instead if it typing "thing" it managed to spell "thong" for me and I didn't notice lol

 

good type up though thank you

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