After over a year of intermittent Clacking when I turn the key in my Blazer, I have finally learned what may be the ailment for so many of us.
I tried replacing: starters (3), Starter solenoids (4), Starter Relays- after the Doghead Mod (4), most of the ignition circuit wiring- including the battery cables, Batteries(2), Alternator (1), GP Card(1), Ignition switch (1), and back-up/neutral safety switch (1).
Then after all that I found that I was getting the starter gear from the solenoid locking into the Flex-plate teeth. That's IT!
It happened to me again yesterday. I was in the parking lot of my Harbor Freight, when I turned the key and heard the dreaded clack- which I though I had cured with a starter shim 2 weeks ago. I left my tools at home because I was just installing a cargo mat. I went back into the HF store and bought a 3/8" ratchet and a metric deep socket set (for the 15mm socket). I slid under mt Blazer and loosened the starter bolts. As the second bolt was being backed-out I heard the solenoid spring pull the starter gear free. Re-tightened and started the Blazer with no further problems.
The reason I think I have been reading of this clacking sound at start-up by so many forum members is that the aftermarket starters we buy are often milled; thereby creating too close a fit between the starter and the mounting surface on the engine block.
There has been much talk about shimming on this forum; I believe that the suppliers of rebuilt starters don't always supply the information about them having milled the starters- and most don't supply the shim to make up for the lost deck height (Wilson Electrical does send a shim and a measuring key (Allen wrench) with their rebuilds.
I highly recommend carrying a ratchet with a 15mm (or whatever your starter bolts happen to be) in your vehicle at all times. If you get this particular NO START, then all you need do is slide under and loosen as I did above- Listen for the retracting Bendix, re-tighten and get it home for further shimming.
Remember, there is no such thing as "it didn't come with a shim, so it doesn't need one", OR "I have never shimmed". If you had OEM on it, it may not need shimming; but it may. If you bought a rebuilt starter or changed starter types: Direct Drive (OEM type) to Gear Reduction type, you may certainly need a shim if your supplier mills their rebuilds- you can ask; but it is wiser to drop the cover plate when installing any starter and shim per supplier's instruction or use a paper clip to check clearance. Ask me how I know.
I tried replacing: starters (3), Starter solenoids (4), Starter Relays- after the Doghead Mod (4), most of the ignition circuit wiring- including the battery cables, Batteries(2), Alternator (1), GP Card(1), Ignition switch (1), and back-up/neutral safety switch (1).
Then after all that I found that I was getting the starter gear from the solenoid locking into the Flex-plate teeth. That's IT!
It happened to me again yesterday. I was in the parking lot of my Harbor Freight, when I turned the key and heard the dreaded clack- which I though I had cured with a starter shim 2 weeks ago. I left my tools at home because I was just installing a cargo mat. I went back into the HF store and bought a 3/8" ratchet and a metric deep socket set (for the 15mm socket). I slid under mt Blazer and loosened the starter bolts. As the second bolt was being backed-out I heard the solenoid spring pull the starter gear free. Re-tightened and started the Blazer with no further problems.
The reason I think I have been reading of this clacking sound at start-up by so many forum members is that the aftermarket starters we buy are often milled; thereby creating too close a fit between the starter and the mounting surface on the engine block.
There has been much talk about shimming on this forum; I believe that the suppliers of rebuilt starters don't always supply the information about them having milled the starters- and most don't supply the shim to make up for the lost deck height (Wilson Electrical does send a shim and a measuring key (Allen wrench) with their rebuilds.
I highly recommend carrying a ratchet with a 15mm (or whatever your starter bolts happen to be) in your vehicle at all times. If you get this particular NO START, then all you need do is slide under and loosen as I did above- Listen for the retracting Bendix, re-tighten and get it home for further shimming.
Remember, there is no such thing as "it didn't come with a shim, so it doesn't need one", OR "I have never shimmed". If you had OEM on it, it may not need shimming; but it may. If you bought a rebuilt starter or changed starter types: Direct Drive (OEM type) to Gear Reduction type, you may certainly need a shim if your supplier mills their rebuilds- you can ask; but it is wiser to drop the cover plate when installing any starter and shim per supplier's instruction or use a paper clip to check clearance. Ask me how I know.
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