I have my engine on a stand and finally got the oil pan. My original plan was to do a re-seal to fix some oil leaks, check the timing chain and clean/detail as best I could. Now, after removing the oil pan I am wondering if I should go with a full rebuild. Before I embarked on this project it ran very well.

My main concern is the deposits and sludge that hopefully can be seen in my photos. What you you do?

 

That engine looks clean as a whistle to me. No need to touch it.

 

I mean you did a lot of hard work already. Would it be bad to pull one of the main journals and see how they're holding up? It's right there you know?

 

You lose nothing stripping it down, nothing says that you need to replace anything but having got that far checking bearing condition, clearances (maybe - depends how things look - plastigage them), ring and ring land condition - costs nothing but time - just be methodical and make sure everything goes back exactly where it came from and I do mean everything .... dare I ask what the trigger to tear down that far was ?

 

Boy, that is sure a clean looking engine..... I can't say that I would even have a fleeting thought of a rebuild if it is based on the way that engine looks!! It's beautiful!!
I would save my enthusiasm and $$$ for something else!
John

 

I have been slowly going through the whole car cleaning/replacing/refurbishing. I am doing this because I find it therapeutic. I pulled the motor due to a few oil leaks and to do a general detail and reseal. However, a full disassembly and rebuild was not in the plan. I was not planning on nor was I looking forward to removing the heads.

Based on the responses to my initial thread I think I will just button it back up and call it a day. Thank you everyone!

 

Extremely sensible decision. These engines (V12 and straight 6) are bulletproof.

 

Look at how massive the parts are compared to every other engine. That crankshaft alone weighs 78.8 pounds. It’s a forging of EN30 steel( really good stuff) then once all the machine work is finished the whole crankshaft is heat treated. In the event a bearing fails chances are the crankshaft is totally fine.
There are 4 bolts on each main cap and 6 on the last one.
The main bearings are 3.00”. That size is typically used on 500 cu inch engines. The connecting roads are 2.300 A Chevy 350 inch V8 has 2.100 dealing with a much bigger 4+ inch piston compared to the 3&1/2 inch on the V12
every part of that engine is massively overbuilt. ( William Lyons intended to take that engine out to 500+ cu in.
He built his engines based on the pre-war BENTLY which was massively overbuilt for long term durability.

 

..then I found this! Ugh! I also broke one of the studs holding the timing cover on. Broke it flush with the block. I sure am glad I took the cover off. Would have been very sad to button everything up only to discover the broken tensioner when I tried to start it up.

Any advice on removing the broken stud from the block?

 

Looks below the surface to me. Broken off in block I'd leave it to a pro rather than take the risk of messing up the block and calling a pro after the event - depends how much skill you have vs how much you think - when I broke bolts in the heads I managed to get a visit - 2 bolts done in under 2 hours (I know my limitations)

There are ways to get a good centre on the stud - make a jig that guides the punch - then drilling is about keeping it at a perfect 90 degrees to the hole (as best you can by hand) and gradually increasing drill size, the aim is to remove as much bolt as poss whilst potentially creating a little heat - left hand drill bits may spin it out and preserve the threads but don't count on it - aluminium threads once galled really need a thread insert -

Doesn't look so clean to me as the crank case - question is are you going to replace the chain (makes sense to me but as some here may tell you I have OCD issues about such things)

 

I think the chain will be fine (sorry Ben!). Agree about a professional to extract the stud; but if, as Ben says, you make a jig and use LH drills, you also will be OK.
At least with the cover off you can replace the tensioner and see what you are doing!

 

Worry not I'll get over it you know me - why spend 10 when I can spend 1000 .... if the wife but knew, though I think she suspects.

 

Don't kid yourself Ben; she knows, they always know, they are born knowing.

 

The best way is to make a bush that fits the matching timing cover hole.
The bush is steel or brass and a neat fit in that hole.
Drill a hole about 2.5mm thru the bush centre.
That is your jig so you drill the broken stud dead centre.
Plenty of oil or grease in the bush so you do not drill it out.
Easy if you have a lathe. 10 minute job to make a bush.
No lathe ?
If you join a local Jag club sure to be somebody with a lathe.
I have one, if somebody from the club needed a bush I would happily make a bush.
Helps keep the V12s going for longer.
Left hand drills a good idea too.

 

I had no idea masochism was therapeutic. I have been working on getting exhaust pipe to manifold nuts off. Maybe it will make me a better person, if I manage to do it without using high explosives. Those cat converters really get in the way

Doug

 

LOL! Sometimes bad words are uttered. But for the most part the end result is rewarding. A broken stud in the block may test my theory though.

 

Thank you for this advice. It definitely provides a path for getting the remaining piece out of the block. I am located in the USA and don’t know anyone with a lathe but perhaps I can find a bush online somewhere. I do have a drill press so maybe I can find something close and use the drill press to shave it down to fit timing cover hole.

 

Lathes are cheap, China makes millions cheap enough for a hobbyist to buy.
I have one for my business that cost US$3k and excellent value for money.
Hobbyist type one to make small items like your bush start at perhaps US$500, or even less..
Ask around your friends and neighbours. Fair chance somebody has one.
Model railroad enthusiasts often have one, or know somebody who has.