distributor installation question

[GavinT]

Oh . . . that's a bit trickier if the head's already installed.

To measure the bore hole height above the drive gear means ensuring the gear is hard up against the underside of the head.
The only way I can think of is to remove the oil pump and insert a long rod up the spout to keep it in place while you measure.

The drive gear just sits on the oil pump spline in the block. Given the gear is forced upwards during normal running, the limit is where it contacts the underside of the head. I don't think the actual gear float matters. It's always going to be running against the underside of the head no matter how much was skimmed off.

I notice the first pic in Reply #10 shows light witness marks which would seem to confirm califkid's findings about the drive gear being forced down and cutting chips below the gear.

califkid, I reckon you're probably saved yourself some heartache by taking that engine apart.

[califkid_66]

thanks  im just going to shim under the distributor the amount that was shaved of the head
crossflow head 3.681 my crossflow head 3.625  so 0.056 shim under the distributor should
do the trick

[jbcollier]

:-)

Sounds good!

… I think.

[califkid_66]

it should be ok it’s a learning curve
while i was at it i noticed witness mark on the distributor witch shows where it was mating with the oil gear

[GavinT]

thanks  im just going to shim under the distributor the amount that was shaved of the head
crossflow head 3.681 my crossflow head 3.625  so 0.056 shim under the distributor should
do the trick

Question - has this engine ever actually run without a shim under the dizzy?
I ask because if there's been enough axial load to cut chips under the gear, the situation might have damaged the internals of the distributor similarly.

I've had another bright idea. 
Perhaps the dizzy drive gear could be held in place for measuring with a BFMagnet?
I'd still want to measure the actual components.

[GavinT]

… I think.

I could never be accused of that . . .
On my first crossflow, I did a dry build of the head to check something or other and left out the head gasket because It wasn't strictly needed for what I was doing . . might have been valve/piston clearances . . can't remember.

Anyway, I went to turn the crank and heard a strange 'tick' sound and found the crank wouldn't move.
I never figured out what the 'tick' sound was but years later, while doing something else, I discovered part of a gear tooth had broken off the camshaft and was lying under the dizzy gear.
That sounds like empirical evidence the end float of the gear is less than the thickness of the head gasket - ooops. 

[califkid_66]

i don’t know looks like the block ran had glitter in oil and oil was used but top end did not seem to have  run carburetor freshly rebuilt never had fuel head unbolted and came off very easily as if it was just installed the head gasket looked old the pistons were very clean no carbon
pretty hard to tell when you don’t have the history
for the dizzy i not going to use it it came from a fuego
im just gonna continue working on it im not in a hurry i just want to make sure im doing everything right