sealing the end crank cap on an let

[mirpur]

i have finished putting the girdle on the let and realised where the girdle sits on the the last crank cap ie cap on the ie flywheel end there seems to be a very slight leak and the engine isnt even running yet.
im going to have to remove the sump, girdle, all the selaent and remove the cap and seal it with gm black sealent better to do it now than when engine is in the car
what i need to check is

1. having sealent on the cap is there an easy way of removing the cap as its going to be stuck as the sealent is probably also acting as an adhesive

2. will i have to put in a new crank seal

3. when reseating the cap i put sealent around the cap do i also need sealent where the cap ends meet with one another,ie lower and upper cap meet, dont want the sealent squeezing out into the shells

4. is the gm black sealent ok for the job as currently the sealent is blue

[mirpur]

Anyone
I have taken the cap out there seems to be a groove on each side where silicon squeezed into Im just unsure whether I need to out sealent on the bade of the cap as the tolerances are so small
The cap needs a good knock to push in and seat is this normal

[mirpur]

Anyone
I have taken the cap out there seems to be a groove on each side where silicon squeezed into Im just unsure whether I need to out sealent on the bade of the cap as the tolerances are so small
The cap needs a good knock to push in and seat is this normal

[lee303]

use the vauxhall grey sealant as it was designed for the job, i usually just smear a little on the bottom of the cap and the sides, then install the cap and then force sealant down the grooves down the side of the cap but forcing the end of the sealant tube in the hole and squeezing 'till you see some sealant seep out of the gap on the front of the cap, never had one leak yet

and yes, a good knock to seat the cap is normal. and use a new crank seal

[mirpur]

Lee where does the sealent leak out from, what do you define as the front of the cap when fitted to the engine, is it wise to lube the shell or will it just contaminate the sealent,
What's the grey stuff I've. been told to use tge black rtv sealent from vauxhall. Part no 90485251

[mirpur]

Lee do you smear sealent on the full base of the cap as I have been told its an interference fit and shouldn't need sealent ,sealent should only be down the grooves as you mentioned

[debeerd]

Down the sides and a splash one the bottom ends.

[lee303]

yes a smear on the bottom of the cap, its not a good enough fit to seal on its own, the sealant will leak out of the join between cap and block, lube the crank surface rather than the bearing, it won’t contaminate the sealant, and the grey stuff is the stuff vaux use for this job, i do have the part number at the garage but not with me till the weekend if you can wait that long

[mirpur]

if you can get me a part number that would be good, haynes manual says to use the part number i quoted
do you smear the whole base of the cap
i will drop some engine prep lube on the crank just thought it will leak towards the rtv and not allow it to set properly
is it best to remove the crank seal, fit the cap,and then refit the seal

[lee303]

not sure how many time i can say smear the bottom of the cap, its fairly obvious where the cap hits the block, i will get the part number tomorrow and post it here

[mirpur]

lee understand you saying smear the bottom of the cap but the end cap is much wider than the rest of them do i smear the whole cap including the area around where the holes are for the arp studs or just the edge of the cap more towards the fywheel side, just dont want to over do it and have rtv squeezing out everywhere

[Tathan]

if it does, just remove it

[mirpur]

yes will do just dont want to risk it squeezing anywhere between the crank/shell if thats at all possible, never done one before dont fancy doing this job once the engine is in the car lol

[lee303]

heres the GM sealant i use


you smear the bit that needs to seal, so obviously not the mating face for the bearing bolts, but the bit that becomes the block wall when fitted

[mirpur]

Lee any idea what the difference is between your sealent and the black rtv sealent vauxhall gave me,is yours like a rtv texture, wanted to fit this tomorrow will have to wait until Monday as vauxhall didn't give me the sealent you have in the pic,I will smear just the edge of the cap near the crank seal and leave the rest of the base of the cap

[sportboy]

ive used the black sealant and the grey using the same method to apply it as lee and never had a problem with either leaking.

[Tathan]

the colours are for the applications - high temp/oil proof/etc. Black and grey are both oil proof though, so use either.

[mirpur]

Tathan both are oil resistant, is the grey one better in any other is it more temp resistant

[Tathan]

I know this, I told you!

Just use either ffs!

[lee303]

i prefer the grey stuff, but the black stuff will be fine if that doesn’t confuse matters

[mirpur]

Lee stop complicating matters lol black it is then

[Tathan]

No, use grey.

[steveboyslim]

No, use black.

Steve

[Tathan]

I suggest the copper one.

[nevcontractor]

I've been dogged by this problem on my Z20LET. I took my end cap out from the engine (from underneath) and replaced it using oil resistant high temp Locktite (before I knew that it was vital to use the Vauxhall stuff). This helped cure my leak by about 75% but I still get some leakage. Based on this, I would say deffo use the correct Vaux stuff and really squeeze it in hard under pressure with a syringe into the 2 grooves. Maybe overtighten the 2 bolts that secure the end cap as well by a smidge, as I think mine leaks from the area in contact with the sumpgasket (though this is hard to proove).

HTH.