crankshaft wobble...need advice guys

[knightowl73]

im totally convinced now that my 350 motor is wore out. its never ran at anything but 8* timing without popping and clattering, runs at 210* all the time even with a 165* thermostat, and ive also tried a 195 and 180 and still the same. no thermostat results iin the needle hardly ever moving. it seems to have a little power, not what im knokwn to see in a 350, most everything ive owned had one too. ive always noticed a bit of wobble in the balancer, but put a new trans in a few days ago and noticed underneath my flexplate and torque converter are wobbling 3x as bad. im sure this means my crank is tweeked or bearings going bad, even tho no leaks or anything.

by the way, the truck is a '89 350 1-piece rear main motor, mild elgin cam (not sure what grind), '89 350 tbi heads, eddy performer intake and 600 carb, new dizzy with accel supercoil, 6 mo old tuneup. could never get any performance whatsoever until the day i added the supercoil, after everything else, so another clue it is going. havent ran a compression check yet, but dont think with the crank issue ill deal with this motor, tho it is only at like 30-35 running warm.

I do have a '87 truck 305 motor with 80k on it and a set of 305 HO heads on it, was thinking of using the eddy performer intake i have thatll work on those heads and just running it. i would like to put a cam in it before it hits the truck tho. keeping costs to a minimum, would you use the 305 you have or would you rebuild another 350? its a daily, and would i see a increase you think between the new 305 and the worn 350?

[benoit454]

if I had the 305 and needed it to run daily I'd do it while I built the 350 for it. I would compression check it first though.

[83burban]

I don't think you crank is the problem. If the bearings were going bad or you had a bad crank you would have no oil pressure and you would hear loud knocking most likely. The wobble could be the result of a warped flywheel or a balancer that needs to be replaced.

Based on your description it sounds like a mismatch in the parts used in the engine build. You said that it will clatter when you try and change the timing - this is because the cam and the heads are not appropriately matched - and the timing that you have it set at wont be the best for power as a result.

I would try and get the specs on the cam and post up what the casting numbers are for your block and heads - so that we can decode them and give you a better combo of parts or tell you if they are ok together.

This way you wont have to swap motors and hopefully not spend a ton of money if you don't have to.

And while I was at it, I would do a leak down and compression test on the engine to establish that there aren't any internal problems that will need to be fixed before throwing money at it.

[knightowl73]

well i dont know too much about the cam except that it is a elgin one. i bought this truck from a guy who's son built him the truck and thats all the guy knew pretty much.ill get the numbers but i had looked them both up when mortec.com was up and seems like it was just pulled from a truck with a cam and headwork only by word of mouth. could the balancer really be making the rear of the crank wobble that much and not be a big deal because id ratherprobably use a vortec instead of rebuilding this one. id have time to find one for a good deal while riding on the 305.
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[knightowl73]

by the way, i am going to be doing the compression and leak down test this weekend hopefully if weather is permitting. if that all seems fine then what do i do not knowing the cam specs? the closest i can probably do is get my dads dial indicator and try to find the lift that way, but would have to guess using those numbers as to what cam is in there. that seems like not an easy thing to do or is it? ive heard of it but never done it. i am also concerned of there being a cracked head with the temp issues, and dont really know how to diagnose this either without pulling them and looking. there is no water in my oil