Author Topic: I'm still thinking about a re-power....  (Read 7467 times)

Offline tekebird

  • Hero Member
  • *****
  • Posts: 2263
Re: I'm still thinking about a re-power....
« Reply #30 on: May 04, 2008, 07:42:41 AM »
1L and 2R's

Offline TomC

  • Hero Member
  • *****
  • Posts: 8645
Re: I'm still thinking about a re-power....
« Reply #31 on: May 04, 2008, 09:29:17 AM »
Chaz- although some have opinions on how hard a two stroke is to overhaul compared to a 4 stroke, here are a few comparisons.  2 stroke has a blower-to properly set up a blower you need to make sure the blower lobes are have the proper clearance between both of the lobes and the blower case-along with proper end play.  Add to that if you have a by pass valve in the end plate.  On 71 series, you have to size and fit the dry cylinder liners.  On my bus, the liners were not sized properly, so only 65,000 miles after the bus company overhaul, I had to replace one cylinder head and have the block bored .010 over to use .010 over cylinder liners (that's on the outside, the inside bore is still standard for standard pistons).  Also, if you install the pistons into the cylinders wrong, the rings will either break or wear out prematurely.
Now let's go to a 4 stroke.  First, they have no blower.  Installing pistons and liners involves just oiling up the O rings with veggie oil, installing the pistons much like a car and pushing them in (and checking for deck height).  To me, an overhaul of a 4 stroke is easy compared to a 2 stroke.
If you do try to tackle the 2 stroke overhaul, make sure you get da book on 8V-71 overhaul.  Also is suggested you have a 2 stroker mechanic fit and install the cylinder liners and pistons-makes all the difference between a long lived engine and a engine that will be done before 100,000 miles.  Good Luck, TomC
Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline Chaz

  • Hero Member
  • *****
  • Posts: 1541
  • 4108, 8V71 w/auto .
    • Aesthetic Metal Studio
Re: I'm still thinking about a re-power....
« Reply #32 on: May 04, 2008, 10:09:55 AM »
Thanx Tom. That info is appreciated. I would never attempt an overhaul without someone to at least help me. And even then, I would more prefer to just help and learn. I have plenty mechanical knowledge but prefer to learn the easy way.  ;)
 The mechanic I have used is a guy who has worked on them his whole life. He works as a mechanic at a stone quarry (s) and also has a shop on the side. If he would let me hang out and help I'd be more than happy to. Then maybe in the future I would attempt a little work on it myself.
  Either way, I need to schedule a "check up" using all the info you guys have offered. I appreciate it!!!
Pix of my bus here:
What I create here:
"Imagination is more important than knowledge". Albert Einstein