Source for Alloy Rocker Cap that DOES Seal Properly

[Spit_2.5PI]

I was just browsing an old thread from 2013, "Useless So Called Upgrade Parts ?" when I came across a post from TR NIALL:-

Quote

Alloy Rocker Covers with Caps that don't Seal properly .

Well, my alloy rocker cover cap always seems to weep a little oil. I've just found out the hard way that it's not the same fitting as a standard rocker cover cap as the alloy type has an internal bayonet (standard is external). The cap is heavily chromed and has a tiny central hole which I think is the source of the leak. Would anyone know where I might find a compatible cap which doesn't seep oil please?

Cheers, Richard

[Rodbr]

If you are talking about a type that has two tabs and goes through two slots on the cover, these do not normally leak and if they do it's because the seal to the cover isn't great.

I am tempted to say that it might be more to do with excessive crankcase pressure.

You could try being creative and seal the hole with JB Weld!!!! This might force a worse leak elsewhere.

Try removing breather and put you palm of your hand to seal cover hole to assess the pressure at the valve train. not sure of the engine you have but you might have a blocked or restrict breather lower down forcing pressure up the the pushrod tubes.

in theory oil should not be pushed out the breather only gases!

Rod

[BlueTR3A-5EKT]

Ceandess in Wolverhampton are/used to be the makers of chrome oil caps to the industry.

 

My solution to the oil mist problem on a standard filler cap  

From “in the shed this weekend” thread. Dec 2021

Got fed up with oil breathing out of the oil filler cap, dripping on the rocker cover and ultimately dripping down the back of the engine.

The addition of a shaped part inside the oil filler cap has stopped the oil breathing issues.

The modification is a simple internal/external flanged & coned plug fitted with a Loctite coated screw to the cap.

  The only hassle was drilling the spring steel insert of the cap.   Done with a masonry drill.

 

Edited August 26, 2022 by BlueTR3A-5EKT

[Spit_2.5PI]

Thanks for the suggestions guys. Will check crank case breather - maybe fire trap is blocked. Should have said, cap is similar/same as this one from Moss.

Cheers, Richard

[DRD]

I have the same cap and similar issues which results in oil stains on the inside of the bonnet. I've not yet found a better cap though.

[ntc]

It’s simple as the topic I started cheap bling don’t work fit the original it works and yes you can buy a proper alloy cover and cap that works you get what you pay for.

[BlueTR3A-5EKT]

How big is your wallet?   Could be fun if it fitted.

https://swiftune.com/parts-shop/swiftune-billet-oil-filler-cap-2.html

[DRD]

11 minutes ago, ntc said:

It’s simple as the topic I started cheap bling don’t work fit the original it works and yes you can buy a proper alloy cover and cap that works you get what you pay for.

No the alloy rocker cover is much better than the tatty leaky old original steel one. The vent hole on the cap is just a minor annoyance. 

[ntc]

8 minutes ago, DRD said:

No the alloy rocker cover is much better than the tatty leaky old original steel one. The vent hole on the cap is just a minor annoyance. 

Not so just learn how to fit correctly 

[ianc]

Tony Sheach has designed an alloy rocker cover which has:

- groove on the mating face to take a neoprene seal, so as to seal cover to cylinder head

- neoprene ring to seal the filler (no breather), which is in the middle, not at one end, of the cover

- neoprene ring on each of the holding down "nuts", providing a seal

- outlet on the middle of each side, one being closed, the other with a take-off for tube to catch tank (or whatever one wishes).

I have fitted this cover to 4VC, and it looks excellent. 

Ian Cornish

[BlueTR3A-5EKT]

12 hours ago, ianc said:

Tony Sheach has designed an alloy rocker cover which has:

- groove on the mating face to take a neoprene seal, so as to seal cover to cylinder head

- neoprene ring to seal the filler (no breather), which is in the middle, not at one end, of the cover

- neoprene ring on each of the holding down "nuts", providing a seal

- outlet on the middle of each side, one being closed, the other with a take-off for tube to catch tank (or whatever one wishes).

I have fitted this cover to 4VC, and it looks excellent. 

Ian Cornish

Photo?

[ianc]

It was too windy to have the bonnet open at Ambergate, and I knew someone would ask, so Maddy has obliged with her mobile phone.

The aluminium catch tank came from ManoMano.  It's bolted to the inner wing, has one litre capacity and a plastic level gauge on the far side (so not visible).

I fitted the anti-run-on valve years ago - it helps, but I continue to slip the clutch in 1st gear to stop the engine once it is hot.

High tension leads are good old copper - never had reason to fit any fancy stuff!

Header tank for coolant is top left in 1st shot - see my article in TR Action 112 (February 1994), also in Technicalities B18.

Ian Cornish

[BlueTR3A-5EKT]

11 minutes ago, ianc said:

It was too windy to have the bonnet open at Ambergate, and I knew someone would ask, so Maddy has obliged with her mobile phone.

The aluminium catch tank came from ManoMano.  It's bolted to the inner wing, has one litre capacity and a plastic level gauge on the far side (so not visible).

I fitted the anti-run-on valve years ago - it helps, but I continue to slip the clutch in 1st gear to stop the engine once it is hot.

High tension leads are good old copper - never had reason to fit any fancy stuff!

Header tank for coolant is top left in 1st shot - see my article in TR Action 112 (February 1994), also in Technicalities B18.

Ian Cornish

Nice looking product.

I like the central filler so it will suit all 4 cyl TR applications.  Good production sales planning.

For smooth and sexy that looks like it’s going quickly, I still like the Offenhauser rocker cover.   

 

[Charlie D]

Ian,

I’m intrigued by the way the heater valve attaches to the cylinder head. It looks like a bit of rubber pipe just pushed on without any hose clips.

Or is it just my eyesight.

Charlie.

[stuart]

2 hours ago, Charlie D said:

Ian,

I’m intrigued by the way the heater valve attaches to the cylinder head. It looks like a bit of rubber pipe just pushed on without any hose clips.

Or is it just my eyesight.

Charlie.

I would say its your eyesight as its the standard angled steel adaptor screwed into the head and the valve screwed directly into that. Same as all normal 4/4a fitments.

Stuart.

[Charlie D]

Thank you Stuart,

My excuse is that I’m more used to sidescreens.

On my 3A I just have a short pipe coming out of the head connected directly to the heater hose.

In the pictures I thought that the steel pipe was actually rubber.

I will go to specsavers tomorrow.

Charlie

[ianc]

Stuart is correct - standard arrangement at head connection.  However, in order to be able to ensure that I can cut off all water flow to the heater in warm weather, I have inserted a plumbing cut-off valve in the rubber pipe between the heater valve and the bulkhead.

Ian Cornish

[peejay4A]

11 hours ago, BlueTR3A-5EKT said:

Nice looking product.

I like the central filler so it will suit all 4 cyl TR applications.  Good production sales planning.

For smooth and sexy that looks like it’s going quickly, I still like the Offenhauser rocker cover.   

 

I’ve got one of those. It looks great but it’s on the shelf. There’s no provision for a breather hose to a catch tank and I didn’t want to bodge a plumbing fitting onto it. It also fouls the rearmost roller rocker pedestal.  Nice to look at though. 

[BlueTR3A-5EKT]

1 hour ago, peejay4A said:

I’ve got one of those. It looks great but it’s on the shelf. There’s no provision for a breather hose to a catch tank and I didn’t want to bodge a plumbing fitting onto it. It also fouls the rearmost roller rocker pedestal.  Nice to look at though. 

Are you intend to use the Offenhauser rocker ?

PM me if you are thinking of selling it.

Peter W

[tim hunt]

11 hours ago, ianc said:

Stuart is correct - standard arrangement at head connection.  However, in order to be able to ensure that I can cut off all water flow to the heater in warm weather, I have inserted a plumbing cut-off valve in the rubber pipe between the heater valve and the bulkhead.

Ian Cornish

Is that a Ford Escort anti-run on valve I spy Ian? Neat installation.

Tim

[ianc]

Tim: according to my records, it was from Moss on 24th August 1998, Part STN127Z.  I mounted it there because I wanted to minimise the length of tube in order to maximise the valve's effectiveness.

Still listed by Moss, but at an eye-watering £108.90 + VAT (I paid £38.00), and the bracket is now affixed in a different way.

Moss's current offering is very similar to ADU9535, which I found listed on eBay at £111.30.

Ian Cornish

[Spit_2.5PI]

Sorry for the delay in getting back. The bank holiday weekend away (not in the Spit ) was closer than I realised!

Thanks for your suggestions and comments everyone. It was only later I remembered I should have said that this is on a 2.5 PI engine.

On 8/26/2022 at 9:47 AM, Rodbr said:

I am tempted to say that it might be more to do with excessive crankcase pressure.

I warmed the engine up, disconnected the breather tube and covered the hole. Then, with it ticking over, removed the filler cap and put a rubber glove over. It inflated very slightly - not enough to actually lift itself up, if you see what I mean. I would guess that this is a normal amount of pressure?

On 8/26/2022 at 9:47 AM, Rodbr said:

you have but you might have a blocked or restrict breather lower down forcing pressure up the the pushrod tubes.

Breather lower down and pushrod tube pressure? I don't recognise this. Is it the Wet Liner engine Rod?

It was at this point I looked at the filler cap and saw the hole went right through inside to outside - there is no rubber seal or similar as I had assumed there would be.

On 8/26/2022 at 9:47 AM, Rodbr said:

You could try being creative and seal the hole with JB Weld!!!!

On 8/26/2022 at 11:23 AM, BlueTR3A-5EKT said:

with a Loctite coated screw to the cap.

Yes, I like both these ideas.

On 8/26/2022 at 9:55 PM, BlueTR3A-5EKT said:

How big is your wallet?   Could be fun if it fitted.

https://swiftune.com/parts-shop/swiftune-billet-oil-filler-cap-2.html

JB Weld or a set screw are cheaper and I don't want to disturb the moths in my wallet.

BTW, I didn't have an alloy rocker cover for bling, I wanted to reduce tappet noise.

Anyway, turning to the breather tube, I had a look at the flame trap and could see glints of light through it. Removing the snorkel to the air filter and putting my palm over the front of the plenum "log" would drop the engine idle slightly with or without the flame trap to fresh air - there wasn't a significant difference. The result was similar connected to the rocker cover with the cap removed. Covering the breather tube with my palm still over the end of the log would easily stall the engine. Likewise with breather to rocker cover and covering the oil filler.

I think that the oil weeping from the filler cap "pinhole" is a characteristic of the PI set up which carb cars don't suffer. The breather goes to the plenum which is at nearly atmospheric all the time. It's just the pressure drop across the air filter - a K&N in my case. So there's not much vacuum on the crank case, unlike a carb set up where the breather is downstream of the butterflies so there's a strong suction all the time except WOT. There's bound to be a fine mist of oil in the engine, hanging in the air, and over time some of it exits via the filler cap hole instead of the breather tube. Perhaps especially so after some enthusiastic driving when the engine is particularly hot?

Cheers, Richard

Edited September 1, 2022 by Spit_2.5PI