Crankshaft is back in

[mallard]

I got the crankshaft back from the machine shop Friday and installed it in the block with much better results this time. I did not turn the mains last time because they were still in spec for ten under. When I installed them with the new 010" under main bearings they were measuring 004". The ideal measurement should be 001"-0025". This time I had the mains turned 020" under and after installation they measured 0015". Much better than the 004". The rods were also checked and they were fine.

 

[mallard]

As you can see from the picture the Plastigauge measures much better than the 004" last time.

 

[mallard]

The next maesurement was for the crankshaft end float. I had to use 2 standard thrust washers, and 2 005' thrust washers to get the correct measurement. After some sanding on the back side I got it right where I wanted it. 004" is on the tight side but is within spec.

 

[tdskip]

Great progress Keith - thanks for the update and pictures.

 

[mallard]

The last thing for the day was to set the original rear main seal. I found this out by accident that the mandrel from Moss motors was to large to fit into the bearing cap when it was still in the upper 90s to 100 degrees outside. When I went to install the crank the first time it was in the 60s and mid 30s at night and the mandrel would fit in just fine. So today I put the mandrel in the freezer and put it in the bearing cap and waited for it to warm up and expand. Then when it did expand just before it was to tight to remove I put in the screws and made some marks on the block and cap. Then I removed them and the seal, and cooled the mandrel again and repeated the process this time putting aviation sealant on the back side of the seal and inserted the mandrel. After waiting for the mandrel to expand again I tightened up the screws, and hoping for a seal that will not leak (to much)

 

[tdskip]

Interesting Keith!

 

[martx-5]

From what I've heard on this forum, the Moss Mandrels are oversize on the seal diameter. I borrowed one from one of the guys in the local Triumph club, and sure enough, it measured 2.826" when the workshop manual has the dimension at 2.822". To further complicate the issue, there has been a lot of talk that the dimension in the workshop manual is not right either, and that the dimension that works best is 2.819". It was Randall that brought this to my attention.

When I took my engine apart, which leaked very little oil from the rear seal before I started the resto, I didn't take the seal pieces off the block and the bearing cap. Once the crank was out, I bolted the main cap back on an measured the seal opening...well, it measured very close to 2.819". I made a new mandrel from a piece of delrin I had at work, and that is where I set the rear seal. Six months of driving, and (knock on wood) the engine has no oil leaks.