New S1B owner

[jbcollier]

What's the tank like on the inside?  If it's clean, good news.  Lotus Supplies (Banks) used to have S1 tanks available.  I bought a pair of alloy ones for mine.  The "crossover" pipe is a short length of 5/16"/8mm fuel line.  Not a big deal.

[314159td]

Inside is totally clean with the original coating(paint?) to the midway mark, then very light rust above that, slightly heavier in the neck. This tank is unreasonably thick and heavy for a Chapman design. Outside bottom wasn't doing great so that justified the blast and powdercoat. Sender works fine on the bench and in the car so that can stay for now.
For the crossover, I don't like having to open both caps to fuel, so I also run an air line higher up on the tanks and that's now double the work. I have a very cheap station a block from my house so capacity is only a problem on road trips, which I already carry jerry cans for to game the different tax rates between surrounding states. It's a "when I gut this entire car if I still have it in a decade" thing, but I am happy to have the tank logged in CAD regardless.

Looks like a rainy (and humid) weekend, so I might have the head on and running on starter fluid soon. Gotta re-read that manual section to make sure nothing is missing. I wish we had something like the Spitfire workshop manual, which is literally more pictures and diagrams than text.

I also had an electronic ignition module come in, $26 on Aliexpress and the same manufacturer as my equally cheap one on the Spitfire engine. Will make a post on how to find and install those cheap units after confirming this one works. PerTronix is highway robbery for their component cost.

[jbcollier]

Get a Renault 17 factory manual (or R16 depending on what you have).  It covers the engines and transaxles in great depth with every step carefully illustrated.

[lotusfanatic]

 

Welcome!
it's great to see another S1!
Mark

[314159td]

Went and dropped the pan today, noticed a little bit of water right at the start of draining it. Figured that might be condensation from having the head off but curiosity got the better of me to I refilled the water jacket. No drips or change in water level over several hours, like before. Then I got a sheet of closed cell foam and a piece of aluminum, held those down to "seal" up the water jacket, and used a 10 PSI regulated air nozzle to blow into the block drain port.
 
Steady stream of drips from the forwardmost cylinder 

So, looks like this engine (and transmission) is coming out anyway.
I'm planning to get:

• liner, ring, and piston set: https://www.renault16shop.com/Piston-and-liner-set-Lotus-Europe,-diameter-82,50,-76-mm
• liner seals: https://www.renault16shop.com/7700508016,7700508017,7700509556
• standard size main bearings https://www.renault16shop.com/7701348413,0996105000,0996049000
• standard size big end bearings
• crankshaft thrust washers
• full gasket set, though I already have some/most https://www.renault16shop.com/7701450505
• oil pump impeller dohicky (the part that wears out), pending measurement of mine. https://www.renault16shop.com/0996053300
       also need a new screen/just the pickup tube, not finding that except included with the whole cast pump housing.
• engine and transmission mounts, no idea who has those at a fair price. My understanding is that some sellers sell Anglia mounts, which have issues.
• rear suspension bushings if they exist
• transmission gaskets and seals, will place another order for internal transmission bits after cracking it open
  
• clutch disc, pressure plate, throwout bearing https://www.renault16shop.com/7700502795-7700586960-7701348537
  
• clutch cover (mine is missing, would like to buy this used) https://www.renault16shop.com/7700526333,7700510333
  

Unsure if I would need to replace the timing sprockets, guessing not, but definitely a new chain and tensioner. Renault 16 shop has some wack prices, might be cheaper to get the whole set with sprockets anyway.

This list is mostly for myself, but if anybody thinks I'm missing or don't need something, let me know.


In better news the original radiator is proofed to 10 PSI and the heater core has a leak...in a super easy spot on one of the tanks. I also think that somebody has messed with my axles, as one is of a noticeably larger diameter than the other, but I'm going to ignore that for now.

[GavinT]

Your link for the pistons is for the 697 (1470cc) engine.
Given you're in California, I suspect you want pistons for a Type 65, 821 engine (1565cc)?

Best not to buy the bearings & thrust washers until you've measured the crank - same thinking for the timing sprockets.
Yes, I don't think I've seen the oil pump screen as a separate part.

Bushings and mounts etc. should be available from one of the US usual suspects.
Same for the clutch but I'll let someone else chime in because I've lost track of what's going on with the throwout bearing.

[314159td]

Your link for the pistons is for the 697 (1470cc) engine.
Given you're in California, I suspect you want pistons for a Type 65, 821 engine (1565cc)?

Nope, for better or worse. Series 1B with the 1470 engine (697-4), grey market import to Texas before they were officially sold here.

[jbcollier]

+1 on stripping and carefully examining what you have before ordering.  If the crank bearings look fine, then just pull the pistons and liners.  Maybe only a hone and new rings is all you require, other than gaskets of course.

Same with the crank shims.  Measure your end play.  If it’s good, no need for new parts.

[314159td]

I pulled the main caps off one at a time, seems like the crank journals are okay enough but bearings are a bit icky, might have been run with contaminated oil. Didn't check the big end bearings but assuming the same story there.
My experience with crank thrust washers is on the little Triumph engines, which chew through quickly and blow up if you forget to change them. I figure not so much here?
Is that something I can get a sense of with the engine installed and having someone press the clutch? Tried to shove the crank back and forth and didn't notice anything, but I have a dial indicator and magnet base I can use for that.

I'd rather not have an un-rollable car for too long, but I should probably just accept it and figure out how to get the back end on a furniture dolly.

Honestly didn't even think to measure the bores, just assumed they were okay enough to send it but not worth replacing gaskets and keeping the old liners. Almost completely smooth.

[Kendo]

People have built contraptions to hold the half shafts in the right place to let the car be rollable without an engine, if that’s a holdup.

[jbcollier]

Dial gauge on a crank web and two screwdrivers to push the crank back and forth.  Specs in manual.  Triumph engines have heavy clutches and only half thrusts.  They can wear quickly.  Renault engines have full thrusts.

[GavinT]

Nope, for better or worse. Series 1B with the 1470 engine (697-4), grey market import to Texas before they were officially sold here.

Oh, OK.
Just one thing to add; piston & liner sets usually include a set of 'paper' ring seals for the sleeves.
Might be worth checking with R16Shop to be sure.

[314159td]

So, I did some measuring of things and started getting concerned, eventually making this spreadsheet. This post slightly references my posts in this thread: https://www.lotuseuropa.org/LotusForum/index.php?topic=3575.15

Boxed values are directly measured/not calculated. I CC'd one chamber of the head about a hour ago, will do all of them eventually and double check.
Red values are pulled from here:http://www.syer.net/donor_cars.htm
Notably my head is thinner than the mentioned minimum thickness, it was skimmed by the interim owner who identified the warped head and hasn't been reinstalled. I have some minor concerns about valve interference if anybody has a head thickness number for when that becomes a problem.

Anyway...standard raised pistons are out of the question unless I'm running race gas. I'm pretty sure 13:1 is around the highest production cars got on carbs and mechanical ignition. I have no intention of using anything other than currently available pump gas, which tops out at 91 AKI here (at sea level).
 
9.2:1 with flat-top pistons seems reasonable? My Corvair is 9.25:1 and timed per factory specs but occasionally pings in hotter months, though you can't really compare engines like that. The odometer is about to roll over and it might have hot spots or other issues so  ¯\_(ツ)_/¯

I could just slap standard renault pistons in and run on 89 or 91 AKI gas, or I could buy the raised top pistons and machine them down *some amount* to achieve a specific CR between 9 and 13:1, possibly even the original 10.25:1 though I feel like that would ping tremendously?

Does anybody have experience running Lotus stock-spec 10.25:1 1470 engines on 91 AKI gas? Preferably with the stock cam and maybe even with a skimmed head? Any info on the pinging limit is useful. 
AKI is just the standard US octane rating if you're unfamiliar, before someone mentions how much higher theirs is (in MON or RON)

[jbcollier]

Could you explain your calculations?  What is “head volume” as opposed to “combustion chamber volume”?  If your calcs have the flat-tops at 9.2, I can’t see how the raised tops would give 13s.

Some engines are prone to knocking and pre-ignition.  The Renault Cleon engines are not.  You can run high CRs.  Maybe not 13+ though.  I’m running into the 11s quite happily, albeit with a crossflow.

[314159td]

Head volume is the volume of one chamber of the head, as you would get from CC'ing it. Piece of polycarbonate with a hole and a burette and such.
Combustion volume is "Volume at top dead center", which has to add in the additional space created by the head gasket, and subtract any volume for a raised piston. Of course, that assumes that the top edge of the piston exactly meets the bottom of the head gasket.

Flat top to raised top does give an increase from 7.6:1 to 10.25:1 (if I'm understanding things correctly), and those have a non-linear impact on CR so 13.7 doesn't seem absurd to me.

I used the published Renault and Lotus engine figures to calculate the approximate volume of that raised piston section (~16cc, feels correct) and apply that to my engine, in addition to just normally calculating the current compression ratio with flat top pistons. My head is skimmed about a millimeter, and seems to have ~17cc smaller combustion chambers than stock. If anybody has CC'd a stock head I can sanity check that 56cc number.

Here's a direct link if anybody wants to poke around the math: https://docs.google.com/spreadsheets/d/1xGBd_ZZnM73jezMyqmUdjQCRs1Sq9V1fw_AyUOi6bPo/edit?usp=sharing
I had a couple Otto cycle engine lab reports in college and I'm reasonably confident in the numbers, but there could also be aspects of the Renault engine I'm missing. If the pistons *don't* just about reach the bottom of the head gasket that would throw the numbers off slightly. Going to take more measurements to fully validate over the next week.