Tear Down and Reassemble Unstarted 1.7 built to 2270, 1.7 to 2270 Unstarted 10 Year Old Build Options

[Robroe]

Moved from topic of first start of 10 year old build to tear down, inspect and reassemble. The 10 year old build is from a 73 1.7 to a 2270. Stroked to 78 mm and 96 mm cylinder diameter. Heads are Ham/RAT with 36 mm exhaust and 44 mm intake. Both are nicely ported.

Have torn it down to the case and checking crank end play before I split the case and pull the cam and crank. So far, everything is new and looks in good order. I'm concerned about oil passages being blocked with old assembly lube so a complete tear down and reassemble is happening. Discovered stacked cylinder spacers (4) totaling .150". So looking to replace those with single spacers. So far I can only find .160" spacers from type 4 store and may just use them as impact on compression appears minimal. Was shocked to discover crank end play is .450"! Sure glad I didn't try to start this thing. Will check again in the morning to make sure I'm checking it correctly, but I'm doing the same thing on the videos such as Ian Carrs YouTube engine builds so pretty sure I'm checking it correctly. Now to figure out what to do about that huge end play.

Any thoughts about what to watch out for?

[technicalninja]

I think he's doing it wrong, but I do have a question for the Hawk.

(IMG:style_emoticons/default/WTF.gif)

Why only three shims?

"No less no more" sounds restrictive to me.

I don't think the crank, or the bearing gives a shit about the number of shims...

If there's a LOGICAL reason, I'd like to hear it!

[Superhawk996]

Why only three shims?

"No less no more" sounds restrictive to me.

I don't think the crank, or the bearing gives a shit about the number of shims...

If there's a LOGICAL reason, I'd like to hear it!

I don’t have definitive answer other than that’s what the factory manual specifies.

The engineer in me says the reason is to have two thicker shims interfaced with the flywheel and the bearing with the third (thinnest) shim sandwiched between to protect it from damage and direct rotational contact with the bearing or flywheel.

Why not four?

More interfaces and places for oil to pile up into further decreasing end play? (IMG:style_emoticons/default/confused24.gif)

When using factory parts four would indicate excessive wear on something? (IMG:style_emoticons/default/confused24.gif) you’ve got to admit that we are having this discussion and doing some extra checking since three won’t do it. (IMG:style_emoticons/default/huh.gif)

Someone would inevitably use six thin ones rather than ordering two thick and one thin? (IMG:style_emoticons/default/confused24.gif)

Having a thin shim against the rotational interface is more likely to get hung up somehow and crumple or simply wears too thin over time? (IMG:style_emoticons/default/confused24.gif)

Pretty weak I know . . . That’s what I’ve got.