Engine Rebuild - Oversize Main Bearing Bore

[DavidOliver]

Richard, some weeks ago a new block was advertised in our For Sale section.
As Photobucket has kicked it, you can no longer see the available parts in Garage Clearout (mid June)

Good Luck
Dave the cog.

[Pete Boole]

Pretty sure it was Kieran - Fueltheburn - that was selling it.

Pete

[paulsx]

Also pretty sure it was an lc small liner block not the plated liner one

[rbgosling]

Also pretty sure it was an lc small liner block not the plated liner one

Yeah, that won't work then - according to Mike Taylor the Nikasil / aluminium liners won't fit right in the earlier block. Even the later block isn't certain, as there are different fittings for the power steering pump for some. Mike says he has one block that will be right, if I can't find any bearing shells then this is what I'll have to do.

QED Motorsport were no good; no reply from JAE (but it's still 5:30am in California); Paul Matty suggested I tried South West Lotus Centre, just waiting on a call back from them.

At this stage, if I can find a set of +15thou bearings that are also oversized for a ground crank, I'll take them, and grind my crank down to match.

[JerryS]

Richard, have you checked the latest Factory After Sales list? There usually various odd +15 shells listed.
- Jeremy

Thanks for the suggestion Jeremy - do you know where I might find this?

Used to be put up on the tlf forums:

https://www.thelotusforums.com/forums/t ... le/?page=3

List here:
https://www.thelotusforums.com/forums/a ... p?id=42327

[JerryS]

Had a look (at the tlf 2016 list), only seem to list these +015 shells:

(Plain Lower)
B907E1171F Main Shell+015"OD/-.010"ID(SP) qty:154 £6.25

(?)
A912E1991S MAIN SHELL+015"OD/-.010"ID qty:3 £5.74

(Plain/Notch) Rear Lower up to Engine No. 20874
A912E1997S MAIN SHELL+015"OD/-.010"ID qty:7 £4.88

[rbgosling]

Had a look and sadly now they only seem to list these +015 shells:

(Plain Lower)
B907E1171F Main Shell+015"OD/-.010"ID(SP) qty:154 £6.25

(?)
A912E1991S MAIN SHELL+015"OD/-.010"ID qty:3 £5.74

(Plain/Notch) Rear Lower up to Engine No. 20874
A912E1997S MAIN SHELL+015"OD/-.010"ID qty:7 £4.88

Thanks!! I'll take a look. They are all for a crankshaft that's been ground 10thou, so if I can put together a matching set I could be good to go. Happy to grind my crankshaft to match, but when I measured it was right at the bottom of the tolerance for standard size, which may be near the top for 10 thou ground, I'll have to check...

[JerryS]

Just Googled and found ClubM100.com has a 2017 Factory After Sales list:

(Plain) Lower. Quantity of 5 from Engine No. 20875
A907E1171F MAIN SHELL+.015"OD/STD ID (SP) £1.67

(Plain lower)
B907E1171F MAIN SHELL+015"OD/-.010"ID(SP) £6.25

(Plain) Lower. Quantity of 5 from Engine No. 20875
C907E1171F MAIN SHELL+015"OD/-.020"ID(SP) £9.36

Qtys not listed on the M100 list. I got the descriptions from the DeRoure site.
As the list seems to vary maybe worth checking with the factory to see what +15 sizes they actually have on the shelf.

I'm not sure exact spec of the set you need, maybe buy a shedload of the plain STD ones and get grooves machined into them?
- Jeremy

[rbgosling]

Well... I might have tracked some down at http://www.elise-shop.com. I put in the Lotus component numbers, they came up as obsolete for standard and 10 thou reduced I/D, but for 20 thou reduced I/D they were listed, priced, and order-able. So I ordered some - for £253.66 (but at least I should be able to get a refund on the shells I already have). Now just awaiting the email saying sorry, they don't have them after all...

If they do have them, of course, I will then have to pay to get my crankshaft ground to match. But at least I'll be able to complete my engine. And it'll (probably) still cost less than buying a replacement block and bearing housing.

[rbgosling]

Have you checked with JAE in California. They were having all Lotus bearing shells reproduced by the company that supplied them with racing shells for other engines. I've not checked with them recently, but they carried them the last time I asked.

Regards,
Tim Engel

Good call Tim!! Just had a nice 'phone call with Jay from JAE. He's got the 5 plain (lower) shells, and can get 4 grooved + hole (upper, bearings 1, 2, 4, 5) shells from someone he knows. Only one he can't get is the plain + hole (upper bearing 3) shell. The options for that one would be to use an extra lower plain shell and drill a hole in it, or just use my old bearing shell - the upper bearings shouldn't be as worn as the lowers, so it should be OK.

This won't be cheap - $400 or so is £300 these days - but still cheaper than the elise-shop.com option by the time I'd have paid to get the crankshaft ground too.

Better cancel that elise-shop.com order...

[paulsx]

Richard is that going to work out cheaper than using another block?

I'll have a look at the one I stripped as I kept the crank and the shells so maybe the one you need is better than yours

Paul

[rbgosling]

Richard is that going to work out cheaper than using another block?

I'll have a look at the one I stripped as I kept the crank and the shells so maybe the one you need is better than yours

Paul

Well, TBH I haven't asked Mike at Lotusbits what he wants for a block and bearing housing, but I'd be surprised if it is much less than £300. And that £300 will be mostly offset by getting a refund on the shells I have already bought, too (£190 for heavy duty shells and another £50 for the molybdenum coating).

Yes, if you have some used shells, it'd be good to compare to mine, and pick what looks best!

[paulsx]

I think he quoted me £150 but didnt have one I needed at the time, might be worth asking before you send your shells back.

[rbgosling]

Well, assuming Garry Kemp refunds me in full for the main bearing shells I already bought, the swap to the new ones should only cost me £70 or so. That also has the benefits that:

• I get to keep my existing block and bearing carrier with the car it belongs with
  I don't need to pull my liners from my block to fit into a different one (and I don't have a liner pulling tool with which to do so), with the risk that the nip will be wrong
  I don't need to clean up another block (bored of cleaning!)
  The block remains available for someone else who might need it

On the other hand, I may just have tracked down and used the last set of +15thou OD, standard journal size bearing shells in the world, so I've denied anyone else of those!

[Esprit2]

I contacted JAE about +.015 bearing shells, and they don't have them any longer either.

Joe did say something about having shells that will fit, but they don't have an oil hole through them. It would be necessary to install them in the block, then using the block's oil feed passage as a guide, match-drill a hole through the bearing shell. That doesn't sound 'good' to me, unless all other options are worse.

Regards,
Tim Engel