I AM BUILDING A 350 FROM SCRATCH FOR THE FIRST TIME IN MY LIFE. I KNOW NOTHING, BUT WHAT I AM LEARNING FROM MAGS, MANUALS AND THE NET. I AM AT SOMEWHAT OF A ROADBLOCK. I HAVE BOUGHT (BOUGHTEN?) TWO DAMPERS, 1 OEM AND ONE CAT FLUID TYPE. NEITHER ONE SEEMS TO GO ON THE CRANK FAR ENOUGH TO HIT THE SEAL ON THE TIMING COVER. MY MICROMETER TELLS ME THAT THE DAMPERS ARE 6 AND 8 THOUSANDTHS SMALLER THAN THE CRANK SNOUT. WHAT TO DO? I DON'T REALLY WANT TO DISASSEMBLE THE ROTATING ASSEMBLY. CAN THE DAMPER BE MACHINED A LITTLE?
4 Jaw Chuck
06-11-2002 03:24 PM
Yes they can, what perplexes me is why are they too small? Something is not right, either the crank or the balancer. Find out what is the cause before you machine anything, what is the ID of your balancer bore and what is the OD of your crankshaft snout?
06-11-2002 05:01 PM
The vibration dampner to crankshaft snout is a machined interference fit. Do you have a dampner installation tool? The end of the Crankshaft is threaded for the retaining bolt. A dampner intall tool threads into this hole and allows you to press the dampner on the Crank snout. Also make sure there are no Burrs on the crank, dampner or indexing keys. Good Luck.
06-11-2002 09:36 PM
One other thing you need to be aware of is when you install the damper, be sure you have lubed the seal real well. If you start the car on a dry seal, you will probably ruin it.
4 Jaw Chuck
06-11-2002 10:02 PM
Studes right about the fit, typically this would be called a transition fit as the amount of interference could vary from engine to engine but is around 0.0005" to 0.0000". Having 0.007" to 0.008" interference is waaaaay to much for this diameter and would take a multi-ton press and some dry ice and heat to get it on there. You could forget about ever getting it off again if you did this.
06-12-2002 06:12 AM
AS I SAID, I AM NEW TO THIS ENGINE BUILDING, SO MY ID AND OD DIFFERENCE IS PROBABLY 0.0006 = 0.0008, NOT 0.006. I BROKE ONE INSTALLER ALREADY, THEY AREN'T CHEAP. NOW, TELL ME MR. 4 JAW CHUCK, DO YOU THINK THESE TOLERANCES ARE WITHIN THE HOT/COLD APPLICATION REALM? THANKS TO ALL
06-12-2002 06:17 AM
P.S. MY EYES ARE SHOT, I HAVE TO WRITE IN ALL CAPS.
4 Jaw Chuck
06-12-2002 01:28 PM
Having six to eight ten thousands of an inch is more like it, this is still on the high side for a stock component but totally in line with an aftermarket high performance piece. The aftermarket stuff if typically a little tighter because of the greater abuse it will see. You could polish a little off your crank snout until it became a tap fit or size for size (0.000 interference) I have rarely seen any reason to have them an interference fit.
Or you could just send back your balancer as the bore is a little on the small size or you could warm it up in your oven at 250 F and then slip it on?! She'll fit with a little heat.
definately heat it in the oven first to 250. lube seal. can pound on with an 8x8 inch piece of wood a foot or so long. if you have a Summit balancer it has to go to the machine shop first to smooth the snout. they are horrible and will eat seals unless perfectly smooth.
06-14-2002 09:50 AM
thought i replied already but where'd it go? definitely heat the damper. use potholders to take it out and pound it on with a big-*** block. i used a 8x8 about a foot long. check clearance with a plastigage before you keep beating the **** out of it like i did, because i had to machine some of the snout off. if you bought it or it came from summit, it will have to go to the machine shop anyway, because their snouts are too rough to use and will eat the seal right up!! put the water pump pulley on and then liine up the balancer pulleys before you go machining the end off.