Cam Cover Sealing Nuts

[alexblack13]

To each their own guys. Respect the man's choice. I can see where he is coming from and there is nothing wrong with this good idea, but... its Terry's choice.

He will be fine either way. V V good advice all round I say....

Be happy!!

Alex B....

[Frank Howard]

Alex,

Terry started a thread asking about how to go about sealing his cam cover studs. Three of us offered a solution that stops the leak before it gets past the cover. As a bonus, this solution requires no special parts and happens to cost almost nothing. Terry responded that he didn't feel comfortable putting pieces of hose in the engine.

If Terry had said that he couldn't add the rubber fuel hose because rubber fuel hose is no longer available in his country, then I would respect his decision. If Terry had said that he already glued on his cam cover and didn't want to spend the money on another cam cover gasket, then I would respect his decision. But Terry said that he didn't feel comfortable about adding rubber hose to the inside of his engine. I don't respect that decision because it appears to be based on some sort of paranoia about adding rubber to the inside of a Twin Cam. I take issue with your response that I must respect Terry's decision.

I pointed out that the engine has plenty of rubber in it already so there is no logical reason why he should be afraid to add more. I understand that it's his car and that he can do with it what he wants, but I don't have to respect his decision especially when it's based on some sort of fear of adding rubber to the inside of an engine that already has rubber in it. You mentioned that you could see where Terry is coming from. Please tell me where that is because I'd like to know.

One more thing. Terry won't be fine either way. If he seals it using the method suggested by the three of us, it won't leak. No matter how much he spends on fancy gaskets, nuts, and washers that are designed to attempt to seal the leak after the oil has leaked past the cam cover, it will leak. It's like having a head gasket that is weeping coolant down the side of the block. Some might suggest smearing some special sealer on the joint between the head and the block, but the only way you're going to fix it is to stop the leak at the source and that means changing the head gasket. Likewise, the only way Terry is going to fix his cam cover stud leaks is if he stops the leaks at their sources.

While Terry can do anything he wants to do with his car, I can respect or disrespect anything he decides to do.

[rgh0]

I didnt know sealing a cam cover could be so controversial

I listed the rubber tube method as an option. It was not compulsory. I also listed a number of other options including what I do which is just a smear of silicone sealant on a plain washer.

Personaly I dont use the rubber tube method because Ii have never done a long term test of compatability of rubber fuel hose I have with the engine oil I use at high temperatures. I do know others who have used it long term and successfully but specification of hose and oil varies.

To say there are lots of other rubber components in the engine is true. But there have also been lots of reported problems with the rubber drain tube swelling and going soft ( I use an alloy one or none at all). There have been lots of reports of the rubber half moons swelling and shrinking also. Generally the rubber oil seals dont give problems if bought from a name brand supplier but these are made to much more exacting specifications than other rubber components using much more expensive rubber compounds

Over the years I have learned the hard way to not make a modification to a twink or change a component until I do the engineering and understand exactly the impact. I understand how a smear of silicone and a plain washer seals and I am comfortable with it. I am not sure I understand what happens long term to a fuel hose inside the cam cover so i dont used it, simple as that

Sorry for the long response
cheers
Rohan

[Frank Howard]

Rohan,

Your reason for not using the rubber tube method because you are uncertain about the effect of motor oil on fuel line rubber hose is a valid one and that is a reason that I can respect. If you'd like some long term test results, I've done the "engineering" for you not in a labratory, but in two real Twin Cams. I have used this method on both my Elan and my Europa for the past 3 years. While the Europa is mainly a show car and gets relatively little use, the Elan is my daily driver as long as the salt trucks are off the road which can range from 7 to 12 months out of a year. As the fuel hose is compatible with a petroleum product such as gasoline, as you might have guessed, petroleum motor oil does not seem to bother it either. I know nothing about synthetics.

By the way, while I have never experienced problems with the "D" plugs, the rubber drain tube on the Europa has gone soft and has swelled up. It's probably no more than 3 years old as it was replaced when I installed the fuel hose on the cam studs. It's obviously of a lower grade and inferior to the one in the Elan as both cars use the same oil and I have not experienced this problem with the Elan drain tube. Your success substituting an alloy tube is another great idea that I will explore the next time the head comes off. Did you do anything special like thread the hole in the head and then screw in a threaded alloy tube, or did you simple find a tube that fit snug and then added plenty of sealant?

In closing, I appreciate everyone's input including Alex's. I also appreciate everyone's right to modify their cars as they please. As a matter of fact, to the purists, I'm one of their worst nightmares when it comes to originality. I modify my car for myself and for my family as both my wife and my children drive the car on a regular basis. My modifications require no one's respect but my own. I just don't appreciate anyone telling me what I am required to respect.

[rgh0]

Hi Frank

The alloy drain tubes I use are made by the Elan Factory. The press into the block ( I seal with loctite) and they fit into the head with a lip and O-ring. The hole in the head normally needs a little smoothing as it is typically just a rough core plug hole.

I add even more lightness in my McCoy converted head race engines as the conversion machines of the vent chamber in the head and you just blank off the block hole. Most Race engines are vented from the front of the cam cover so this is not an issue.

cheers
Rohan

[terryp]

HOLD THE BUS!!!!
Alex was only trying to lighten the post.

The reason why I didn't give a reason for not going the tubes route was out of respect. If someone has taken the trouble to post and give their opinion the last thing I want to do is to say, no I'm not doing that because ..........

Too be honest I see tube as oil resisting, not completely oil resistant and as such being inside a can cover and being bombarded with oil, I cannot see it lasting very long......
Thats my reason, and the reason I'm going standard washers + Blob!

Terry

[Frank Howard]

The reason why I didn't give a reason for not going the tubes route was out of respect. If someone has taken the trouble to post and give their opinion the last thing I want to do is to say, no I'm not doing that because ..........

Terry,

What are you talking about? Rohan said, "I dont use the rubber tube method because I have never done a long term test of compatability of rubber fuel hose I have with the engine oil I use at high temperatures." What is disrespectful about that?

Even you said, "I see tube as oil resisting, not completely oil resistant and as such being inside a can cover and being bombarded with oil, I cannot see it lasting very long......Thats my reason..." Now you've provided a reason and I certainly don't view that as disrespectful either. Providing a reason only opens up the forum for discussion which is believe is what this site is all about.

Rubber fuel hose is obviously impervious to gasoline otherwise nobody would use it. I see no reason why rubber fuel line would not be impervious to hot engine oil as well. Do what you want with your car, but don't let the idea of rubber fuel hose not being able to survive in an enviroment of hot engine oil prevent you from trying this because from experience, I know that is not the case. If you want to learn what actually happens to rubber fuel line when exposed to hot engine oil in a twin cam, read my previous post. I'm just trying to give you some good advice that has been tested in the field. Happy motoring.

[terryp]

Frank
I'm really sorry but I've lost count the number of times I've bought "Oil Resistant Hose" only to find it doubles in size and goes really wobbley. Perhaps in the US when they say Oil Resistant, its oil resistant!

Terry

[Frank Howard]

Terry,

If genuine oil resistant rubber fuel line isn't available in France, then I can only agree that you should not use the rubber fuel line sealing method. Best of luck.

[rgh0]

For those who want to delve into the engineering of rubber fuel hose a couple of links

http://www.merl-ltd.co.uk/2003_material ... ml#eltable
this gives the properties of most types of rubbers used today commercially

http://www.goodyearep.com/ProductsDetail.aspx?id=10526
A typical fuel hose in the size we are talking about made by Goodyear

You will note the hose has a NBR ( Chemigum tradename) inner for fuel resistance and a CSM outer (hypalon tradename) for water / ozone and abrasion resistance

This hose would probably be OK for sealing a cam cover as both inner and outer are OK with hot oils though this depends especially for the CSM outer on how it is compounded and vulcanized, in making the hose they are not really aiming for strong hydrocarbon oil resistance of the outer.

However not all hoses are equal and other manufacturers may use different combinations of inner and outer that are less suitable and "go wobbly and doubles in size" in accordance with Terrys technical description for no f**king good.

So it can work you just need to be careful to get a suitable hose and leave it sitting in hot oil for a few days to see what happens before you use it to make sure the hose you have is OK in the service


cheers
Rohan

[terryp]

Frank
I was also talking about when I lived in the UK!
(6 most recent years in France, 39 years in UK)

Rohan
That explains a lot , I use to use a rubber breather on my Ginetta and it would de-laminate from the bottom upwards between the two layers, presumably the outer layer not being resistant

Thanks to all!

Terry

[GrUmPyBoDgEr]

Deleted

[Frank Howard]

Rohan,

Thanks for taking the time to find those two excellent links. I actually read both of them with great interest.

http://www.goodyearep.com/ProductsDetail.aspx?id=10526
A typical fuel hose in the size we are talking about made by Goodyear. You will note the hose has a NBR ( Chemigum tradename) inner for fuel resistance and a CSM outer (hypalon tradename) for water / ozone and abrasion resistance

I also noted that they said that CSM has excellent resistance to most chemicals. I would include oil in this group because of the following: They noted that CSM has poor fuel resistance. I've got to believe that if CSM had poor oil resistance, they would have noted that as well.

I recall that my fuel hose was not as sophisticated as that described on the Goodyear site as it appeared to be a simple rubber hose absent of different compounds for the inside, the middle, and the outside. This really got me thinking so I went out to the garage to check my supply of fuel hose. Sure enough, that is exactly what it is. Cheap rubber fuel hose upon which the manufacturer did not wish to even spend money printing their name on.

Perhaps I took a chance installing this in my twin cam. I just used common sense, assuming that a hose that was resistant to gasoline would be resistant to hot oil as well. As it turned out, my assumption was correct as three years hence, the cheap generic fuel hose is holding up just fine in both of my cars. Taking into consideration the properties of all of the various rubber compounds available, I can now understand Terry's reluctance to introduce rubber hose to the inside of his twin cam therefore I can respect his decision not to do so.

[alexblack13]

I was not going to bother replying to Frank's post to me, but he looks to have changed his mind a bit.

I was not asking Frank to respect (or not) any method used by anyone. I was mearly saying respect Terry's decision, which I for one am well happy to do in all cases at any time. So someone turning down a suggestion etc that one makes does not have any effect on me. So long as the person is happy .. Fine.

And Frank.. When I said he will be fine either way.. he would! I for one don't have any leakage below these nuts and I just use new 'douty' type washers every time I have the 'lid' off the engine. Terry's idea of a 'blob' should also do the job.. BUT.... Its up to him. His engine, his decision, his consequence.

I am going to make up the 'O' ring holders as they will work & last forever, Which in my humble is the best nil risk option.

Chill Frank..Don't get your Knickers in a twist.. Could put you off your Turkey!!

Alex B....

[crannyr]

Alex,

When you make your 'O' ring holders make sure that the o-ring you use is a snug fit on the stud. Also the relief in the holder for the o-ring should leave the o-ring a little proud of the holder. The result is that the o-ring is compressed both onto the cam cover and around the shaft.
We have used this method on 4 or 5 cars for over ten years without a problem.
Good luck with yours.

Rick