Flanges, Pumps, paper gaskets and sealants help please

[Penelope Stopit]

I am in the process of fitting new oil seals and water pump to an engine and will possibly be removing and refitting an oil seal housing
The camshaft is out at the moment and a manual tells me to use Permatex Form 2 A or Loctite 518 (pictures posted) to seal the ends of the camshaft caps where they meet the cylinder head

There are a couple of things I need help with

1) Is it best to put a sealant on any paper gaskets I use and do I do this on both sides of the gaskets, there are some scratches where the water pump meets the block

2) Will one of thee above sealants do the sealing of the camshaft caps and the water pump gasket

3) Some idiot in the past has used a screwdriver to lever out the camshaft and crankshaft oil seals and have slightly damaged there housings
I am going to gently remove the burrs from the damage, can I use the same sealant as above for the oil seal outer surfaces at the places that have been slightly damaged

4) Is there a better sealant than what the manual suggests

Thank you in advance

[Krikkit]

There are specific gasket sealers for use on paper seals, I don't think Loctite makes one. Be careful adding any thickness with this, on some parts clearances are designed with the original paper/cork/rubber gasket in mind.

518 is a good, general-purpose sealant, but only good up to 0.25mm clearances. If you have some bigger sections to seal I'd use 5980 (others might work, but that's one I've used) - it's good in thick layers and very strong.

[Penelope Stopit]

Krikkit said:

There are specific gasket sealers for use on paper seals, I don't think Loctite makes one. Be careful adding any thickness with this, on some parts clearances are designed with the original paper/cork/rubber gasket in mind.

518 is a good, general-purpose sealant, but only good up to 0.25mm clearances. If you have some bigger sections to seal I'd use 5980 (others might work, but that's one I've used) - it's good in thick layers and very strong.

Thanks for this, I now don't know what to go shopping for, the special paper gasket sealant could be my undoing on this job, this is why I posted here.
I was not aware of paper gasket sealants
I really do appreciate you pointing this out to me, you have very likely saved me a massive water leak from a cambelt driven water pump that is a nightmare of a job to get out and back in when the engines fitted in place

Cheers good health

[Mignon]

In 40 years of building engines including 20 years of race engines for customers I've never found it necessary to use anything other than ordinary clear silicone sealant from any DIY shed. On sump and rocker cover gaskets i.e thick rubber or cork gaskets a 3mm bead all round and on thin paper gaskets a very light smear rubbed in with your finger on both sides of the gasket so it's just a sheen of silicone that won't affect clearances.

If an oil seal housing (aluminium) has been badly scored then you could use a dob of silicone in the gouges but I'd suggest not putting it all round the seal. Oil seals have ribbed lips on the O/D which generally fill gouges quite well anyway. You'd be hard pressed to find an oil seal which leaks round the O/D even in a damaged housing. If they leak it's where the shaft runs.

[rowley birkin]

I have no idea OP, I just wanted to say that your username is superb !

[Penelope Stopit]

rowley birkin said:

I have no idea OP, I just wanted to say that your username is superb !

Thats very nice of you, I couldn't get "Pitstop", there is a tale to tell about the name Penelope Pitstop but it's a long one, your name brings back memories of some great races over the Rowley Mile at Newmarket UK

Edited by Penelope Stopit on Wednesday 6th June 12:39

[Penelope Stopit]

Mignon said:

In 40 years of building engines including 20 years of race engines for customers I've never found it necessary to use anything other than ordinary clear silicone sealant from any DIY shed. On sump and rocker cover gaskets i.e thick rubber or cork gaskets a 3mm bead all round and on thin paper gaskets a very light smear rubbed in with your finger on both sides of the gasket so it's just a sheen of silicone that won't affect clearances.

If an oil seal housing (aluminium) has been badly scored then you could use a dob of silicone in the gouges but I'd suggest not putting it all round the seal. Oil seals have ribbed lips on the O/D which generally fill gouges quite well anyway. You'd be hard pressed to find an oil seal which leaks round the O/D even in a damaged housing. If they leak it's where the shaft runs.

Thank you for this I will use a thin film of Silicone, I have plenty of it as I fill my partners ears with it before winding the music up
You have given me much confidence about the oil seal housings
Cheers, have a good day

[Mignon]

Penelope Stopit said:

re: Rowley Birkin. your name brings back memories of some great races over the Rowley Mile at Newmarket UK

Rowley Birkin is actually from the utterly brilliant Fast Show and was played by Paul Whitehouse who although a comedian may be the most underrated actor who's ever lived. There's a sketch where Rowley reminisces about the great love of his life who he lost and never stopped loving that is so moving and so exquisitely rendered by Paul that I can't watch it without dissolving into tears.

https://www.youtube.com/watch?v=MlQ9KLrC4Us

[Penelope Stopit]

Mignon said:

Penelope Stopit said:

re: Rowley Birkin. your name brings back memories of some great races over the Rowley Mile at Newmarket UK

Rowley Birkin is actually from the utterly brilliant Fast Show and was played by Paul Whitehouse who although a comedian may be the most underrated actor who's ever lived. There's a sketch where Rowley reminisces about the great love of his life who he lost and never stopped loving that is so moving and so exquisitely rendered by Paul that I can't watch it without dissolving into tears.

https://www.youtube.com/watch?v=MlQ9KLrC4Us

What have you done to me? I filled up

[Sardonicus]

Is this on that XUD? the cam caps either side of the front and rear seals where the cap face meets the head need the smallest smear of RTV and like mentioned already dont/never use sealer around the oil seals circumference, a small nick or flaw then sure but only in that small area to fill the void maybe

[Penelope Stopit]

Sardonicus said:

Is this on that XUD? the cam caps either side of the front and rear seals where the cap face meets the head need the smallest smear of RTV and like mentioned already dont/never use sealer around the oil seals circumference, a small nick or flaw then sure but only in that small area to fill the void maybe

Yes this is for the XUD
Thank you for the information
Should I smear RTV all over the cap face that meets the head, an image of the job doesn't show clearly but seems to advise to put a little sealant around the side edges but I think I've seen something elsewhere that shows it on the front edges

The shims are on their way
I have since found a new camshaft that was priced so cheap that I had to buy it, the original camshaft was quite badly grooved from where the oil seal was making contact and it had also been slightly knocked about in the past close to that groove when someone incorrectly removed the seal by using a screwdriver or similar
I have been given cash back from the engine supplier due to the damage and work involved and this is why I bought a new camshaft
I know.......crazy but....I'ts on its way and I have to build it all back up and hope that the gaps that I've calculated remain the same as with the old camshaft

Edited by Penelope Stopit on Wednesday 6th June 14:19

[Mignon]

I've never found sealant necessary on the caps. They are perfectly machined surfaces and don't leak.

[Sardonicus]

Mignon said:

I've never found sealant necessary on the caps. They are perfectly machined surfaces and don't leak.

I only ever done a very small smear but def not all over the cap base its a left over from my Honda days always done it this way regardless of manufacturer but yes like Mignon states probably not necessary

[Penelope Stopit]

Mignon said:

I've never found sealant necessary on the caps. They are perfectly machined surfaces and don't leak.

Ok thanks
Sardonicus may add something here later
The thing is that I don't want to end up as the man in the middle here and I do very much appreciate the input from yourself and Sardonicus
I give plenty of free professional electrical advice here at PH and much by email and I am thoroughly enjoying the free professional engine work advice I am getting from both of you

This feels like good Karma is coming my way

If there is a debate between yourself and Sardonicus about the sealing of XUD camshaft caps I will enjoy reading through it

Cheers

[Penelope Stopit]

Sardonicus said:

Mignon said:

I've never found sealant necessary on the caps. They are perfectly machined surfaces and don't leak.

I only ever done a very small smear but def not all over the cap base its a left over from my Honda days always done it this way regardless of manufacturer but yes like Mignon states probably not necessary

Talk about crossed posts????

Very good that image explains it, forward of the bearing surface and not around the studs
There are a few faint marks on the head surface where the fronts of the caps fit that are very likely touches of sealant from the past, I will clean the area up and then make my choice

Top class information from both of you....Thank you very much, have a good evening

[Mignon]

Penelope Stopit said:

Sardonicus said:

Mignon said:

I've never found sealant necessary on the caps. They are perfectly machined surfaces and don't leak.

I only ever done a very small smear but def not all over the cap base its a left over from my Honda days always done it this way regardless of manufacturer but yes like Mignon states probably not necessary

Talk about crossed posts????

Very good that image explains it, forward of the bearing surface and not around the studs
There are a few faint marks on the head surface where the fronts of the caps fit that are very likely touches of sealant from the past, I will clean the area up and then make my choice

Top class information from both of you....Thank you very much, have a good evening

Theoretically a small amount of oil could get to this forward joint by coming through the cam journal and then going across behind the the back of the seal but I've never seen it happen in practice. The leakage path would be miniscule because the O/D of the seal itself seals most of that split line. If the seal was not pushed back fully against the rear of the housing then yes there might be a tiny length of split line which constituted a gap but I've always found those forward split lines also make very good contact with each other. For very close fitting machined joints like these such as the two halves of boxer engine crankcases (VW Beetle etc) there are very thin anaerobic sealants, almost fully liquid, which don't interfere in any way with the joint being bolted up and then set firm or even hard. Damned if I can remember the make I once bought specifically for a boxer engine build but that was the only time I used anything other than silicone in an engine build.

On purely theoretical principle I suppose I couldn't object to a smear of that sort of stuff being used on this part of the caps but in practice I've never seen a leak there. At at least no customer has ever come back and mentioned one. I suggest after you've cleaned all the surfaces up you see how tightly those caps fit against the head face and if you can see any daylight through the joint you think any oil could get through then by all means make the appropriate decision. I also concede that I recall traces of old hard sealant there when I've stripped these heads down so yes it is used at the factory.

I lightly rub down all such caps and their mating faces on the head with an oilstone before rebuilding to ensure a burr free perfect joint and the potential issue becomes a non issue.

[Penelope Stopit]

Thank you for this, I now fully understand what this part of the job is about and what to be looking for, with all this information I will now be able to make decisions depending upon what I encounter during rebuilding
Much appreciated

[Sardonicus]

Penelope Stopit said:

Mignon said:

I've never found sealant necessary on the caps. They are perfectly machined surfaces and don't leak.

Ok thanks
Sardonicus may add something here later
The thing is that I don't want to end up as the man in the middle here and I do very much appreciate the input from yourself and Sardonicus
I give plenty of free professional electrical advice here at PH and much by email and I am thoroughly enjoying the free professional engine work advice I am getting from both of you

This feels like good Karma is coming my way

If there is a debate between yourself and Sardonicus about the sealing of XUD camshaft caps I will enjoy reading through it

Cheers

Dont worry I am certainly not trying to step on Mignon's toes just my cents worth I know that engines are his specialty , I often find his replies educational sometimes there is more than one way to skin a cat and now you have both ways

[Penelope Stopit]

Sardonicus said:

Dont worry I am certainly not trying to step on Mignon's toes just my cents worth I know that engines are his specialty , I often find his replies educational sometimes there is more than one way to skin a cat and now you have both ways

Thank you, all is much appreciated, I have much more confidence in completing the job to a good standard since the both of you have past on your priceless knowledge to me

Knowledge is everything, money comes with it

[Sardonicus]

Just make sure when you fit the camshaft and fit the bearing.caps that you take the pistons away from TDC by rotating the crank pulley 90 degrees from TDC this way when you initially bolt the camshaft into place you dont suffer interference between valves and pistons you can bring it back when you have positioned the cam correctly with the 8mm bolt/locking pin through the cam pulley