S3 4.2 in a boat update

Hi to all
Well the block and cylinder head are finally back from the shop.

I had 20 thou removed from crank,because of a slight out of alignment and the very badly burnt journal.
I got the shop to put the rope seal in, they do them a lot, and I don’t .
The CH had pretty much everything done skim,valve guides on exhaust,new valves,new bearings,hold down kit fitted, etc,I also paid the extra and had it all adjusted and gapped, big time saving issue, once I get to that stage.
Still lots of parts cleaning and painting to be done, but I feel like I’m really getting somewhere now. Generally it is still a pleasure to work with, and the experience is very rewarding, I know my limits, and machine work is for the machine shop, in my opinion.

The distance piece on the nose of crank, has an O ring seal inside it, anyone confirm part number for me, keep going around in circles.

The pistons were all measured and ok, the gudgeon pins were removed polished and are ok. Honed to standard.
I’ve got new big end bearings fitted and checked in con rods, I have new piston ring set,new circlips for small ends, new sludge plugs, it goes on and on.
Anyway all good so far,
So the 3.8 block (original engine in boat, minus the CH)and complete bottom end, I shall sell to help move the project along, I saw a block only , a 7B on EBay UK the other day for £2k !! and it had a crack, between bores, and generally in a pretty poor state, the one I have is in good condition in comparison, it’s only downfall is that all the bores are 20 thou over. We shall see.


I think this is the part number you want EAC8101 hope it helps,

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20 thou isn’t a problem, it can go to 60 thou or be re-sleeved back to standard.

The crank can’t be resleeved, good news and thanks for the update, looks & sounds great Rob!

He was talking about the block.

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Bores are ground over. Cranks are ground under. .20 is fine for almost any engine.

Cracked block for sale. Oh me!!! Well, not so fast. I watched a You tube video. A fellow bring a 37 Willys 4 back to life. He thionks it is a WWII Jeep engine. It is not. but, it is a percssor and very smilar to the Jeep engie that powered many of them.

A carck along the side of the block!!! Another alog the center of the flat head. hsi fix. Greound clean and filled in epoxy!!!
I gravely doubt any longevity///

OTh my son restored and old Case tractor. A similar crack along the side of the block But, my son is a talentyed machinist. Stictched it clsed with drill, tap screw and break off. neat, clena and sound.



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Thanks for input from all,
I stand corrected on the 3.8 block then, I was sure 30 thou over was the max before a re sleeve, every day a school day.
Some won’t like what I NEED to do, but all exposed aluminium parts will be cleaned and etched and painted silver, as the sea water atmosphere will constantly be corroding the ally. Oil pan,front timing cover, CH,bell housing etc.
Black block as standard, and all pulleys and ancillaries a mix of silver and black.
Inlet manifold,( currently army green/blue), I’m thinking bright red, maybe.
The Solex carb, to stay black, with polished brass parts left alone.

The air trumpet to carb, has 3” dia end and fit a K&N type filter to it.

Exhaust (marine manifolds) etched and painted silver.

I’m yet to open the Solex 48nnip carb, but I will have to at some stage, just to make sure all is clean etc, very expensive for re build kit! The gasket between the 2 halves alone is £36 !! £ 225 for the full kit!!

My BIG worry is trying to run a brand new rebuilt engine, with a unique set up, I have the inlet manifold for the 4.2 for twin carbs, and the twin SU carbs from the 3.8 ( which would need a full service/overhaul) or try and borrow a set of good operating twin su, just while I break the engine in.
Lots to consider here.

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Right my bad. Sorry!

Rob - can’t you run it in on the Solex? The rebuild kits aren’t that cheap either and you have to adjust either carb. Then again you might do well selling these, rebuilt, afterwards. If someone could lend you a set that’d be great of course.

Painting the exposed parts is a good idea, no objections I could think of. Clearcoat can go yellow but silver paint won’t, and Jaguar themselves painted many of the heads. Also, many (me too) paint heads with aluminized paint so they look shiny without too much work. If it protects things from a harsh environment… good!

It’s a very basic carb , apparently you can’t re jet it or anything.
Like I say, just a little concerned that when I am in a position to run the engine, that it’s not huffing, chuffing and backfiring as I believe it won’t be good for everything settling in.
Little way to go yet anyway, I shall take lots of pics of internals of carb, should be an interesting autopsy eh

On another topic, of some interest , as things can ditterate over time, my big boat spilled nearly 100 litres of diesel into the engine bay, bloody mess.
Was a very badly dittereated flexible fuel line,

They looked fine from above, but totally rotten on the bottom, I’ve bent the hose open in 2nd pic, lucky I went to check, could have lost the lot.
Had a date of Jan 1988 on them, so they’ve done well. Lol

Glad your still about


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Were that my project and I needed a carb for temporary or even permanent use, I would fab up an adapter and plant a Holley or similar two barrel on it.


This was a serious one Robert…! especially on a boat…
At least now you know it won’t happen again any time soon.

Thanks for all comments,
Solex carb autopsy,

Well I removed lid carefully as I could, didn’t rip the gasket, absolute bonus as there not cheap and it’s really clean. Very surprised!!
I really was expecting a lot of tarnishing etc, so I am going on the assumption that all is well.
When I get nearer to needing it for its purpose I shall fill with fuel, check floats etc, but for now, back in the box.


I might blow through it to see if any passages are clogged and maybe you need to give it a few taps to get the float valves to seal as usual but it seems to be in beautiful condition and that may just work as is!

I could tell you some ‘interesting’ stories with my father’s 38 BMW, Robert - with triple Solex…:slight_smile:

xj6 85 Sov Europe (UK/NZ