Rebuilding Austin Healy Sprite Engine No 9C-U-H 619
948cc A-series BMC
My set of pictures begins to break down here, and I don't have a photo of every
single step. Still, the following may be of interest.
The first thing to do is to ensure that the sprockets are going to line up.
This is how I checked:
If they don't line up, special thin washers are installed behind the gears to
move them to the proper position. I found that the washers I had did the job.
Also, there's a couple of keys that are inserted to ensure that the shaft the
gear is on (crank or cam) does'nt slip (D'OH !) Those are absolutely not a problem.
After that, both gears
need to be taken off and re-installed at the same time as the chain. You can't
slip the chain over the gears once they're on. The cam is timed by lining up
the little dots as shown in the Haynes manual. I triple checked everything,
but this is easy.
This is how things look at this point.
I then checked endfloat with feeler gauges:
The timing chain cover requires a few words, as there are a couple of styles.
Here is the early style that uses a felt seal inserted in a groove in the cover:
(Can you say "leak like a sieve after three miles ?")
Even though it's not correct for my engine, I used the later style cover that
uses a modern seal:
I made sure I had installed all the parts that go inside (oil thrower, cam lock
washer and bolts, etc. . .)
I glued the gasket on the front plate and on the cover. When the engine runs,
the oil that lubricates the chain and the sprockets finds its way back to the
sump through a small drain. When the engine is stopped, some of the oil will
collect at the bottom of the timing cover and will find any imperfection in
the sealing of the cover. This is one area where I ended up with a pretty big
leak and I had to redo this after I'd run the engine a few miles. Did not need
to pull the engine for this, but I still wish I had gotten it right the first
time.
Note that the pulley on the outside of the cover needs to be installed before all the bolts on the timing chain cover torqued down. the seals shown above actually seal on an extension of the pulley that goes back into the cover. Which means that the cover needs to be well centered around the pulley before it is finally secured.
The cover is then bolted down. Not all bolts are the same size and they don't
all use the same torque. No big deal, just a little care needed to ensure that
no threads are stripped, which would guarantee an oil leak.
Finally, the pulley is installed as well, and the retaining bolt. I thought
I would be cute and use a dog to have the ability to hand start the engine,
but I found later that the dog fouls the frame at the front of the engine bay,
so I had to revert to a bolt.
Here's how it all looks, although this particular picture was taken after the
head had been installed.
Note that the pulley securing bolt is not correct and will not fit in the bugeye, it fouls one of the frame members. I believe it is a Morris Minor part that came with a spare engine that I have. I ended up having to take it off and replacing it with a proper part after attempting to put the engine in the first time. A few expetives were uttered at that point.
Next step: work on the cylinder head.