Technical Sump silicon gasket

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Technical Sump silicon gasket

1.9 JTD it just uses silicon gasket ? Is it best to join them wet and leave to dry or spread the silicon around the sump thinly and leave to dry before fitting to engine


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1.9 JTD it just uses silicon gasket ? Is it best to join them wet and leave to dry or spread the silicon around the sump thinly and leave to dry before fitting to engine


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Hi,
Two significant points:
1/ Use the specified sealant.
2/ Do not allow to cure (dry) before fitting the sump.
Most silicone sealants are not suitable for engine use because they are not resistant to oil and fuel and they give off acetic acid when curing that can cause corrosion. Many do not have a high enough temperature rating.
Fiat specify part no 71713686, but LOCTITE SI 5980 (available from Halfords etc) is also suitable. Clean the sump and block flanges before applying sealant. Put a single unbroken bead around the flange of the sump, do not spread it out. Bolt the sump up within 20 minutes of applying sealant. Tighten and torque the bolts in sequence. Start in middle, front, middle back, next left front, next right back etc. just "nip -up" first time around, then finger tight, then torque up. The torque figures are about 2.3-2.8 Da/Nm for the M8 bolts and 0.8-1.0 Da/Nm for the M6.
Leave at least 2 hours before putting oil in. If possible leave overnight or longer.

HTH,
Robert G8RPI.
 
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LOCTITE SI 5980 is a Silicone sealant.

I'm pretty sure most (if not all) Silicone sealants are oil-resistant too.

The reason I don't like it for 'gasket' use is the possibility of it getting into the oil, and blocking oilways.
If used sensibly/correctly though, it's pretty unlikely.

I have seen some pretty bodged uses of it, where people have just splurged it on in great dollops . . . :eek:

I'm sure some of you have seen things like this . . .
en_waterpump_detail_02.jpg
 
That's great I have a alloy sump seal high torque silicon gasket maker so should be ok it says it's specifically for alloy sumps and heat resistant up to 399c so I'll do it in the morning when not raining and I will leave it for 24 hours, thanks for the help


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LOCTITE SI 5980 is a Silicone sealant.

I'm pretty sure most (if not all) Silicone sealants are oil-resistant too.

The reason I don't like it for 'gasket' use is the possibility of it getting into the oil, and blocking oilways.
If used sensibly/correctly though, it's pretty unlikely.

I have seen some pretty bodged uses of it, where people have just splurged it on in great dollops . . . :eek:

I'm sure some of you have seen things like this . . .
en_waterpump_detail_02.jpg
Hi,
No, most common RTV sealants are not oil and fuel resistant. They soften and swell up. It's not instant, but it happens. There are reasons why there are so many types of Silicone sealant. The "best" ones are the flurosilicone types but these are very expensive. RTV should only be used where it was designed to be. The example you show is particuarly bad as it is obviously intended as an "O" ring seal. You should never use RTV with "O" rings.
On the sump, all you need is a single bead with a diameter of about 4-6mm. No more than 1/3rd the width of the flange.
 
What I've always done is apply sealant
Tighten all bolts to just when they're starting to nip
Walk away at that point
Another nip up the following day to compress the set seal
Fill with oil and away you go
I don't necessarily know if that's the right thing to do but it's always worked for me
I like to think of it as making a gasket and then compressing that gasket
I'm sure I'll get told off if I'm wrong?
But I m not changing what I do when it works
 
What I've always done is apply sealant
Tighten all bolts to just when they're starting to nip
Walk away at that point
Another nip up the following day to compress the set seal
Fill with oil and away you go
I don't necessarily know if that's the right thing to do but it's always worked for me
I like to think of it as making a gasket and then compressing that gasket
I'm sure I'll get told off if I'm wrong?
But I m not changing what I do when it works

that's ok with water pumps and the like,
but the sumps are essentially "glued in place";)

that's why when changing rusted-out steel sumps , it'll often be in pieces before the rim seal "let's go", :eek:
Charlie
 
That's cool I am sure it will be ok as long as them 2 crank bolts come out ok bit of a pain them


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Right done the sump, two bolts behind the fly wheel, if you look with a torch you will see two 1cm cut outs shine torch up and you can see half the bolt head, I thought there must be a way to get them out without dropping the box so I slowly turned the crank pulley with a 19mm socket and there is a cut out in the fly wheel big enough to get at the bolts, have to let the gasket sealant dry over night and fingers crossed all well, and Ben there was a small crack in the sump so cleaned with break cleaner an repaired with chemical metal hope it worked or all for nothing ?


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Where was the crack?
I'm so sorry I didn't know it was not in a1 condition
Please tell me it wasn't at drivers side front where I damaged that front fixing bolt hole
At least you found an easier way to do the removal
Well done on that one
 
It was front right about 2 inches long across the flange and at an angle near where them two bolts had to come out it should be ok I think, we repaired it inside and smoothed it off, it was hard to see till I cleaned it, never mind


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