Sump Gasket

richardpope50 · Post by **richardpope50** » Wed Dec 14, 2011 12:54 pm

My TVR RV8 5.0l (steel) sump gasket leaks and as the engine is out of the car I have a chance to change it. However there seem endless cost permutations of gaskets from cork to synthetic, from simple sump to a full bottom set. Cheapest eBay version seems a full bottom kit for £15 all in so appeals to me.

I've not taken off a V8 sump before so:

1. Do I need a full set or just a sump gasket?
2. Is cork fine?
3. I usually use some (standard DIY) silicon to add extra seal. Is this a good idea here?
4. What torque settings are the sump bolts?

Thanks in advance.

DaveEFI · Post by **DaveEFI** » Wed Dec 14, 2011 1:30 pm

The later 'rubber' gaskets for the rockers seem to be a big improvement over cork so I'd guess the same applies to the sump?

Torque setting given for my SDI sump bolts is 10 lb.ft

ChrisJC · Post by **ChrisJC** » Wed Dec 14, 2011 1:37 pm

I have also had oil leaking down the threads of the longer two bolts at the rear of the sump. A few blobs of sealant on the bolt threads cured that.

Chris.

SimpleSimon · Post by **SimpleSimon** » Wed Dec 14, 2011 2:33 pm

TVR originally used silicone sealer but no gasket, i am not a lover of using just silicone sealer on it's own in this area and suggest using a cork gasket with a smear of Wellseal/Hylomar and seal the 2 rear bolts as the holes they screw into are not blind but open at the end, i prefer to use four studs and the rest bolts to locate everything when going up & closing the joint, just in case your curious there have been lots of reported oil pressure failures from over zealous use of silicone sealer's on the TVR sumps, the oil pick-up strainer cant cope with strands of silicone sealer floating around in the oil

gently nip up the bolts in a criss cross pattern and check them in a couple of weeks for best results.

kiwicar · Post by **kiwicar** » Wed Dec 14, 2011 3:15 pm

I do sumps and gaskets on tin work as follows.
Thoroughly clean both sufaces and de-grease, check both surfaces are flat (especially the sump side) with a piece of glass, some spray engineers blue and some brasso (spray the mating face with blue, put brasso on the piece of glass and put it on a flat surface, rub the gasket face onto the glass/brasso and look at it for low spots. . . they will be blue!

). Use the same components and your imagination for the other face.
Once both are flat stick the gasket to the sump with evostick, a wipe of clean oil on the block face and a wipe of silicone on the bolt threads where necessary, but only enough to seal the threads. Tighten them to the correct torque in a pattern working out from the centre two bolts an at least 3 stages finger tight, 5ftlb and 10 ftlb. Remember at 5 ftlb and 10 ftlb your torque wrench may be on the inacurate side, check it! Do not over tighten the bolts, 95% of sump leaks are because the gasket face being distorted because the bolts are overtight.
This is basically the same way Ian Stewart and it works!
Best regards
Mike

richardpope50 · Post by **richardpope50** » Wed Dec 14, 2011 7:22 pm

Many thanks for the useful information.

DEVONMAN · Post by **DEVONMAN** » Wed Dec 14, 2011 11:16 pm

If you have a cross bolted block, 4 of the sump bolts (2 each side)coincide with the cross bolt drillings and these need some sealer on the threads to prevent oil seeping down the sump bolts.

Cheers Denis

davemgb · Post by **davemgb** » Wed Dec 14, 2011 11:45 pm

Cork gaskets seem to come in two thicknesses, one about 3-4mm which is usually quite soft and I try to avoid these. The other is only 2mm thick and quite firm which I've not had problems with provided you seal the bolts as detailed above.

Best sealant I've used is Loctite 3699 - it's a grey rtv type intended for oil and water exposure on engines.

Dave