needing to drill a hole

[andyb79]

This might sound a bit silly but I need to drill a hole and I need to know if it's something I can attack myself of leave for a pro.
I am currently working on my mk2 escort and I'm planning on fitting a 1.7 zetec se engine from a Ford puma, now this is where the hole comes in, the 1.7 is the only engine in the Ford range that has no provision for a spigot bearing in the end of the crank I think it's currently 17mm and I require a hole 21mm. The crank is made of steel and is hardened.
I've asked my local engineering shop and he was going to charge one hour labour to bolt it to his drill ensuring it was level etc and another to drill the hole, on top of that if he didn't have the right size of drill I'd be charged for that too. Now that I could deal with but he also asked for the block to be bare ie no head etc and to be clean which I can understand to an extent but I'm on a tight budget and cannot really afford to spend the extra money on a head gasket, cam locking tool and what ever else I need on top of his bill for the work that's to be done.
I know that the hole can be drilled with the engine complete I just would like to know is this the sort of job that I could do myself or should I let somebody else do it. Have access to a pillar drill if that going to help?

Thanks for taking the time to read this

 

[Pete.]

Cranks are not usually hardened, what makes you think yours is?

 

[andyb79]

The puma cranks are hardened for some some reason. I've heard them called powdered so I don't think the hardening is very thick

 

[711jrp]

Your biggest issue isn't the hardening it's probably nitrided and this is very thin and easy is machine,it's boring the hole concentric with the crank center-line.If it's a few thou off the clutch will judder bad and the first motion shaft bearings won't last too long either.

 

[graffian]

If the crank is drilled it wants to be concentric, so it either wants doing on a mill/lathe or a drill bush wants making. I would
have asked you to bring just the crankshaft;-)

You have thought of a custom bush or bushing the flywheel. Whats the box pilot diam?

 

[Spark plug]

If it was me I would want the crank out, so it could be mounted in the lathe, setup true and board to size.

On another note if you used the puma gearbox, you wouldn't need the spigot bush?

 

[Fazerruss]

If it was me I would want the crank out, so it could be mounted in the lathe, setup true and board to size.

On another note if you used the puma gearbox, you wouldn't need the spigot bush?

I assume he's mating the engine to a type 9 box which needs the spigot bearing to support the first motion shaft.
I agree with what been said, this needs to be perfect and not s job for a pillar drill. I also find it odd that the machine shop didn't Just ask you for the crank.
Have a look on the locostbuilders forum as the sigma will be a common engine and box combination for rear wheel drive kit cars so there may be an easier solution

 

[slim_boy_fat]

If it was me I would want the crank out, so it could be mounted in the lathe, set up true and bored to size.....

^^ What he said.

 

[Cobbler]

Would it be possible to remove the first motion shaft from the box & turn it down to fit the Puma spigot bearing. This surely would be a simple turning job, with no problems keeping it true.

 

[mike os]

or alter the shaft so the bearing is in the flywheel?

 

[andyb79]

or alter the shaft so the bearing is in the flywheel?

Ive been thinking about a smaller bearing and getting the input shaft modified to suit. I will measure the hole in the crank and go down to my local bearing shop on friday (when im supposed to be working, shhhh dont tell the boss)

 

[oilyneil]

+1 on crank only in the lathe with a fixed steady and a boring tool
Depending on your spigot size you could also have a bronze bush turned up instead of a bearing,, it may give you enough room to not bore the crank out.

 

[Wedg1e]

The crank needs to be out of the block as it isn't a 'tight' fit in the main bearings and could/ would move around, albeit by a midgie's todger. I bet the machine shop guy would be thinking of clamping the block to a mill/ horizontal borer bed, which might be simpler than setting up the crank to run true in a lathe.

 

[anjum]

Agree with Spark Plug.
The best option IMO is to remove the crank, gives you a chance to check the bearings and the oil seals, and take it to a machine shop which can do the job properly. No great cost involved in taking the sump off.

 

[Pete.]

I wouldn't have a problem machining it in place using the engine to turn the crank, but you need the flywheel to start the engine and that would be in the way of your machining jig. Try to find someone with a tall enough mill to stand the engine under and stuff a boring tool through it or you're going to have to yank that crank out.

 

[PSweeney]

you could approach this two ways, neither of which would involve pulling the crank out, last resort really as it involves at a minimum a gasket set and rebuild. the benefit of using this motor is presumable good core unit available cheaply.

1) get a scrap box and turn the input shaft down to suit

2) shorten the input shaft 15mm, turn up an bronze / oilite adapter bush, solid 17mm section sat in the crank, 21mm ID section sat outside. Put a nice taper on the outer section, make the 17mm section an interference fit. The bush is only to keep it concentric, a dab of moly grease will suffice

 

[mike os]

I don't see why you need a rebuild just to remove the crank.... turn it upside down and take the bottom end off.....???? only need sump and crank seals ?

 

[roofman]

iff i was stuck between a rock and a hard place ide bolt a thick true piece of steel plate across the back of the block using the bellhousing holes and then use my mag drill which should be a true 90 degree to the crank nose working off the block face...its about the most accurate way without taking the crank out.

 

[andyb79]

2) shorten the input shaft 15mm, turn up an bronze / oilite adapter bush, solid 17mm section sat in the crank, 21mm ID section sat outside. Put a nice taper on the outer section, make the 17mm section an interference fit. The bush is only to keep it concentric, a dab of moly grease will suffice

This sounds like an idea

 

[graffian]

Here's one I made earlier: