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Discussion Starter #1
Here are some pics of a brainstorm I had for a KDP fix on engines with the raised pin boss. Opinions?
 

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There is a method called "staking". Use a punch or chisel and hit the edge of the hole so the dowel pin cannot come out of the hole. The hole should be deformed so-to-speak.
 

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There is a method called "staking". Use a punch or chisel and hit the edge of the hole so the dowel pin cannot come out of the hole. The hole should be deformed so-to-speak.
Did that to my '94 6BT Dodge. "Staking" is a common practice in the machining industry, so it is effective and cost effective. The company I work for does that on nearly all of our assemblies. Never had one fail yet.

(If you've flown on a Boeing or use electricity in your home, you've come into contact with one of our products.)
 

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I did it to my 4BT. There is no way that pin is going to walk out of there on its own.
 

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Seems to me it's like dancing with the devil. Theoretically, and that's a mouthful, staking should work. I've used it in all sorts of machine assemblies over the years, per manufacturer's specs. I've also seen it fail miserably! All you need is some porosity in the casting being staked, and presto, no stake!

You go to all the trouble of removing the belt, pulley and timing cover, take the time to carefully stake it, then reassemble everything. It takes maybe 15-20 more minutes to make it failure proof: fab up a dowel pin tab out of sheetmetal, put it under the bolt with tab pressing in on dowel pin, and Loctite the bolt. Instead of hoping for the best you're absolutely SURE it isn't coming out.

I found that when I fabbed up my dowel pin tab and checking timing case bolts, the ones holding case to block, that most were loose, some less than finger tight! I cleaned and Loctite secured all bolts, torqueing to spec.

Staking SHOULD work fine. A dowel pin tab and Loctite/torque of all bolts leaves no doubts. Which is better? It's time and effort well spent. Just doesn't seem to me like a place to take any shortcuts.
 

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Discussion Starter #7
The "slot" in the dowel pin boss was already there. Broke through when the dowel hole was drilled. That portion of the casting is rather thin.
 

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The "slot" in the dowel pin boss was already there. Broke through when the dowel hole was drilled. That portion of the casting is rather thin.
That agrees with what I'm trying to say. The 'slot' should not have broken through the dowel pin hole, but it did. Staking 'should' work, and it's an approved method in a lot of machine assemblies. But just like that broken part in the casting causing that slot, it's just not 100% dependable! The timing cover bolts 'should' remain tight, but they don't!

Everybody makes their own choices and I only make suggestions. I suggest a 100% foolproof method of addressing the dowl pin issue because the consequences of a failure can be catastrophic.
 
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