Sump rusted through on ZX

Unread post by **Dommo** » 10 Oct 2010, 10:04

the_weaver wrote: The old gasket is stuck to the block. I've removed some of it using a Stanley knife blade, but it's a long job. Is there any easier method of removing these gaskets?

Paul

Unfortunatly that's the only method I found, using sand paper or something abrasive would damage the surface. With a stanley blade make sure it doesnt nick the surface for the same reason.

the_weaver · Unread post by **the_weaver** » 12 Oct 2010, 01:51

I'm still scraping the old gasket off. What a terrible job. I've used a Stanley knife blade and a wood chisel. Even thought I was careful, I have scratched the surface in some places. I hope that sealant can fill in the scratches. It should be better than a gasket anyway.

Paul

Unread post by **myglaren** » 12 Oct 2010, 17:14

One of these:
Window Scraper

Or even better:
Razor-edge scraper

Would make the job less arduous and less prone to gouges and scratches.

the_weaver · Unread post by **the_weaver** » 15 Oct 2010, 01:54

Thanks for the links. I used something similar to the window scraper in the link, amongst other things. I've nearly finished scraping all the bits of gasket off now.

Paul

jgra1 · Unread post by **jgra1** » 15 Oct 2010, 10:55

hi Paul, just a thought, I fitted a gasket to my sump when I did my engine rebuild..

actually scrub this. you've got the sealant now anyway..

hope it's all back together soon..

the_weaver · Unread post by **the_weaver** » 19 Oct 2010, 11:20

I've put the sump on, using Loctite sealant. I haven't filled it back up with oil yet though. I'm wondering whether I've put too much sealant on. It wasn't easy to put the sealant on evenly. It was a bit of a mess, in fact. I expect I've got areas where there's too much sealant and areas where there isn't enough sealant. I didn't know how much to put on, as it doesn't tell you. Would it be a problem if sealant oozed out into the sump? I suppose it could get into the oil, blocking the oil pickup strainer and the oilways. Is this likely? It's fairly easy to break off a bit of the cured sealant, so I suppose it could come off in time and end up in the oil. I wish I'd used a gasket now. I'm considering taking the sump off and using a gasket instead.

Are newer sumps designed for use with sealant, and older sumps designed for use with gaskets? The reason I'm asking is that the old sump had the raised bits (on the mating face) going away from the block. The new sump has the raised bits going towards the block, acting like a spacer. Is this designed to create a space for the sealant, and might not be suitable for a gasket?

I've found some info on a Land Rover sump gasket here:-
http://forums.lr4x4.com/index.php?showtopic=42479

To quote the post:

"The 300Tdi engines should not have a gasket - they have always used RTV type sealant. If a gasket is fitted that is probably why its leaking - the design of the mating face on the sump pan is not flat as it is not intended for a gasket."

I wonder if it's the same on the XUD. Raised bits on the sump might cause leaks if used with a gasket, so maybe I should keep the sealant.

Paul

jgra1 · Unread post by **jgra1** » 19 Oct 2010, 12:34

Paul, I would stick with the sealant.. maybe that's why you need to leave it for 7 days, so it wont fall apart when oil goes in there?

the_weaver · Unread post by **the_weaver** » 20 Oct 2010, 01:28

John

When you fitted your gasket, was the sump mating surface flat, or did it have raised "flutes" on the surface? I'm wondering whether those flutes will cause leaks with a gasket.

Paul

jgra1 · Unread post by **jgra1** » 20 Oct 2010, 10:57

hi Paul.. to be honest my memory is a bit hazy.. the blog may show a pic of the sump? I think the sump face was slightly very slightly convex.. but I am guessing a bit

I dont think I have lost any oil from it though since then,, it's under no pressure down there..

essentially though, the block face and the sump face were wide 'lands' of bright metal..

the_weaver · Unread post by **the_weaver** » 20 Oct 2010, 13:08

The blog does show a picture of the sump. There are no raised flutes. I wonder whether Citroen changed over to sealant because the sump suppliers added raised flutes designed for use with sealant. I'm not sure what would happen if a sump with raised flutes was tightened down onto a gasket. Would the flutes make indentations in the gasket and seal ok? Would the sump sit on top of the gasket and not seal properly? I suppose I could cut indentations in a gasket to accomodate the flutes.

Paul

the_weaver · Unread post by **the_weaver** » 20 Oct 2010, 13:36

I think that if I used a sump with raised flutes and a gasket, then the sump would seal on the flutes, but leak around the bolt holes.

Paul

uncle buck · Unread post by **uncle buck** » 21 Oct 2010, 22:38

Hi,
I had a ZX TD for 9 years & the sump always leaked despite me trying to cure the problem numerous times over the years. I tried gaskets & sealants but always the seal would leak. Each time the sump was removed both mating faces were meticulously cleaned & wiped down with acetone to make sure there was no oil to stop the sealant making a good bond, I even left the engine without any oil in for a couple of days but still no joy. Don't get me wrong the oil never poured out, it was just the odd drip on the garage floor but it was annoying that I couldn't get the thing to seal.

My sump was the type with the reinforcing flutes that pointed upwards towards the block.
I eventually came up with the idea that it was these that were stopping the sump sealing properly so I decided to grind the flutes off. I wasn't sure if the metal would be thick enough to allow removal of the flutes without grinding through, but it was. The rigidity of the sump edge didn't seem effected by the removal of the flutes, probably because it has a slight rolled outer edge.
I refitted the modified sump using a home made thin cardboard gasket with a smear of RTV silicone on both sides and left it overnight to cure before filling with oil, surprise surprise no more oil leak.

So if you can't manage to get your sump to seal get the grinder out.

Cheers.

the_weaver · Unread post by **the_weaver** » 22 Oct 2010, 08:10

Uncle Buck

Thanks for your reply. Some very useful info there. I was worried that the oil might pour out if I used a gasket. If you're saying that it was only dripping then that's ok with me, I'm not bothered about a perfect seal.

Did you actually try the gasket on it's own with no sealant and if so can you confirm that it only dripped in that case?

I've bought a gasket from gsfcarparts now. I think my first attempt at using the sealant wasn't very good. I probably used too much and I expect some will have squeezed out inside the sump, as it's squeezed out on the outside. I think I'll remove the sump, clean off the sealant and have another go with just a gasket.

Paul

Unread post by **Old-Guy** » 22 Oct 2010, 13:16

No direct experience of this engine BUT in general the idea of flutes/bumps in one mating face is to make sure that there's an adequate thickness of sealant that is compressed.

Usually the workshop manual will tell you to not to fully tighten down the sump or whatever, but leave a gap of X mm all round before leaving the bead of sealant to cure. When the sealant has set tightening down fully. This ensures that a cured bead of sealant of the correct thickness formed and then is compressed to make an effective seal.

The 'trick' is to form a reasonably tidy bead on the sump face, then lightly bolt it down/up onto 4 match-sticks as a spacers between 'bumps' and mating face, then whip out the match-sticks before the sealant starts to set.

If the block face is lightly oiled to prevent the sealant sticking to it, the sump can be removed to trim off any excess sealant. Provided there are no gaps in the sealant 'bead', it will make an oil-tight seal when the sump is tightened down to the 'bumps'.

I've used this strategy very successfully in the past with rocker covers that have been distorted by repeated over-tightening - showing my age again

the_weaver · Unread post by **the_weaver** » 22 Oct 2010, 20:21

Thanks for the info, Old-Guy. Your method sounds good. I like the idea of being able to trim off the excess sealant. I removed the sump again today and the sealant was a bit of a mess, as I suspected. It had squeezed out into the sump and there were areas where there wasn't enough sealant. I cleaned the sealant off and refitted the sump using a gasket. Fitting a gasket seems to be much easier than using sealant. I haven't put the oil in yet, so I don't know if it's made a good seal or not.

One question. I notice that the sump bolts seem to loosen and need to be retightened as the sump is being fitted. It might be the gasket compressing over time (say half an hour). I had to go around the bolts about four times, retightening each time. I think it may have happened with the sealant as well, but not as much. I've torqued the bolts down to the correct torque. I'll check them again tomorrow. If they've loosened again, should I re-torque them again? Should I keep re-torquing them for a few days? I'm wondering if doing this will compress the gasket too much. Maybe they're only supposed to be torqued once and then left.

One more question. The sump plug has got a tapered bit on it. I think this is designed to stop it going in too far, to leave a gap for the copper washer, so it gets compressed but not flattened. Have I got this right? If this is the case, then can I tighten the sump plug up reasonably tight? I always used to do them up fairly loosely, as I didn't want to compress the washer too much.

Paul