New Engine Build

[rgh0]

I spoke to soon about the cover checking out all OK except for the back plate recess for the block gallery plug. I pressed the bearing in place, fitted the chain guide and fitted the dipstick tube. I then went to fit the pump seal in the front cover and discovered the drain hole behind the seal was missing

Drilling this hole is not for the faint hearted as it goes in at an angle through a small bulge in the casing on the water side into the space between bearing and seal.

photo of missing hole - yellow mark is where it should be

hole in original front cover

original cover set up in drill press to get the angle right with the drill running through the hole. The new cover was set to the same location to drill the hole needed.

Hole in the new cover came out in exactly the right location. Happy with my setup and drilling

I will be talking to the well known UK supplier about the faults. I presume they get them all from the same source and they need to work on their manufacturers quality control.

cheers
Rohan

[alan.barker]

Well done for putting the hole in the good place. It gives you an early warning of pump seal failure.
I thought you were fitting a front cover with a removable pump capsule
Alan

[pharriso]

Rohan, why is the shaft so off centre compared to the raised boss?

Hole drilled in the pad bottom RH corner seems off centre as well; I'd check these covers over before fitting them

[alan.barker]

Thinking about it maybe it was safer to drill from the inside to be sure of the position
Alan

[rgh0]

Thinking about it maybe it was safer to drill from the inside to be sure of the position
Alan

Yes initially I thought about that but the setup on the drill press was much harder as there is nothing flat on the front face to bolt it down on the drill press bed.

cheers
Rohan

[Certified Lotus]

[quote="pharriso"]Rohan, why is the shaft so off centre compared to the raised boss?

Phil, the original is the same. Looks like the casting is just made that way, even the bolt holes are like that. It?s probably in the right location, the casting just has a ?heavier? side.

[pharriso]

Rohan, why is the shaft so off centre compared to the raised boss?

Phil, the original is the same. Looks like the casting is just made that way, even the bolt holes are like that. It?s probably in the right location, the casting just has a ?heavier? side.

Rohan's is not, look at his picture:

Holes look centred on bosses

[Certified Lotus]

Hey Phil it?s Glen, not Rowan. I think the OEM casting is also off. It?s an optical illusion the way it?s photographed ? Only way to tell is use a micrometer.

[alan.barker]

Rohan,
where was the front cover made

[rgh0]

The front cover came from a UK supplier. I presume they are all made in the same location these days regardless of the supplier, probably somewhere in India or China ?

The bosses for the machining of the various bolt and bearing holes are only approximately located in the casting and are deliberately made oversize to allow for shrinkage and core shift. I presume there is some sort of machining setup jig to reduce the raw casting to the required critical machined dimensions and locate the holes accurately in the critical places.

The reverse engineering of the casting machining has got the back plate relief hole for the gallery plug slightly wrong and the person doing the machining on the day clearly forgot to drill the drain hole in true Lotus quality control tradition

cheers
Rohan

[rgh0]

Fitted the front cover and water pump today. Discovered the chain damper pad prevented proper fit between the front cover and back plate. Needed a bit of filing of the chain damper and relieving of the back plate to get clearance. You really need to check every item as you bolt it together these days as the new parts are not identical to the original.

The new chain damper is painted black - looks nice but it interferes with its proper fit. The original one was not painted and fitted better due to this. i had to clean off the paint.

I use hex socket countersunk UNC screws to replace the flat blade screws that Lotus used as standard and the suppliers typical send. Much easier to fit and replace as you cant get a screw driver straight onto the lower one

[alan.barker]

I imagine you put sealant on the screw threads
Alan

[2cams70]

Yes those holes are through holes. I imagine quite a few twin cams leak due to people neglecting to put sealer on these threads.

[nmauduit]

Thank you for the update : would you have photos of the baffled sump before putting it back on, by any chance ?

yes I have photos I will post some this weekend
[/quote]

Hi Rohan,

winter is rapidly approaching over here, and with it the long postponed upgrades ... among which a baffled sump for my road car as a test bed. I have a couple weeks workshop window that I'm going to make the most of, and would gladly get all inspiration I can before starting welding, so if you have a photo handy... so far I've been thinking of a center cavity with articulated flaps on both sides.

thank you !

[rgh0]

Yes what you say is my basic design for the sump baffles. I use the earlier 120E blocks with the screw in central pickup. If you have the later blocks you need to modify the press in pick up to move it to be central

I have attached some photos

cheers
Rohan