Engine builders....help

[Mizark347]

Stock starter could not turn my 347 with 9.5:1 compression. I took out the engine and am inspecting clearances. I think the rods are too compact on the journals. I cant get a .009 feeler guage between them. I believe thats tight. Is it possible to make clearance, or do i need new ones? Everthing else looks good. Thanks

 

[thumper460]

I like .025 between the rods... you can remove them and then have a machine shop cut them down a little to give the .025, .009 is way tight!! IMO

Just me.........................

Thumper

 

[dastang2]

did you use a torque wrench and look at some specifications

 

[408stroker5.0]

Sorry to hear you had to take the motor out (I remember the thread when you were having difficulties). .009 is fairly tight, but the motor should still turn over even with .009 clearence. I would say piston to cylinder wall clearence would more likely cause a starter to have a hard time turning over an engine if the clearences were too tight. Are the rod's facing the right way against the crank journal? Every rod has a groove on one side of the big end, and that groove has to be facing against the crank journal, not against the rod opposite it. Check that, many people make the mistake of not facing them the right way, and crap happen's when this mistake occurs. (Turn a bearing, poor oil control etc.) Also check the thrust bearing clearence for the hell of it as well while your at it. Myself personally....I suspect piston clearence problem's, or the ring's were installed wrong.
What kind of rod's are you using???
Good luck man, and hopefully you get her sorted out. Keep us posted.

Who built the engine????

 

[Mizark347]

Im thinking the pistons are too tight also. They need a little more clearance. Every thing torqued down to specs. Crank spins great by itself, so rods or Piston to wall clearance. In what case could it be rings?
Thanks guys

 

[87'GTstang]

I'm voting in general piston to sidewall clearance. If you bore an engine .030 over and you get a piston sized for a 4.030 application - it's going to fit unless you personally do something wrong. Also something could be in a bind. Torque specs are VERY critical in a world dealing with thousandths of an inch , ot to mention torque order. Check for what 408stroker50 said, it is critical you install things in the right direction. Some things only work in the correct direction. Also check to see if you have your mains bolted down too tight, i've seen a few people way overtighten these things thinking tighter is better. It either made the crank very difficult to turn or when the engine warmed up, expansion took over and made things swell in a very tight place.

Just remember, take all the time you need in the building process and double check everything, it's better to take all the time in the world doing it right than taking an eternity figuring out what you didn't.