Ok, Monday I got on it(like usual) ;) and I was driving along and about a mile later the engine starting knocking, it sounded just like a really bad rod bearing. After limping back to work I took the engine out and removed the oil pan, much to my surprise everything was nice and clean in the oil pan, no broken rod bolts, or bad rod bearings. I did notice that one of the crank counter weights is or was hitting the #8 piston under the wrist pin just barely. I just built this engine a couple months ago. I accidentally put a crank made for 5.7" rods in with 5.565" rods. So when I assembled it, it took a little clearanceing, not much though. On Sunday I changed my oil and I stuck some of that "Engine Restore" stuff in. When I built the motor I was “economically challenged” :D so I added over a 1/4" stroke without reboring or honing the cylinders. It doesn’t smoke that I notice, but it uses some oil somewhere heh. I was wondering if the Engine Restore maybe didn’t have the same hydraulic properties of motor oil, which caused the piston to get that much closer to the crank and hit it!? The only other thing I can think of is a piece of carbon broke off and was being smashed by the piston, but this is a fresh motor. Does anyone have any ideas? Thanks, Scott

How big was the wheel on your angle grinder that you ended up using to "clearace" the counterweights??

Sounds to me like either you have knocked a rod, main or cracked a piston?? But knowing no more then what you discribe, can't say for sure??

The Restore stuff shouldn't have hurt anything, imho..

pdq67

PS., and that #8 piston pin boss is taking a beating I bet too which SURE doesn't help matters!!! Maybe cracked it??????

I don't think using a can of "Engine Restorer" caused a knock..highly unlikely.I've used that stuff for years in higher mileage motors and never had a problem.

OK Ill investigate further!

scott... dang dude lol, get on aim - don't make me call your house :D

Ok I found the problem. I broke the #8 exhaust valve spring. It's really strange I have .535" springs and I made sure all the clearences were correct when assymblying the heads and motor. Im running a 268XE Comp Cam with springs that are supposed to be good to .535" lift. With my 1.6/1.52 rockers Im at .509" intake, and .487" Ex. Anyways even with way more then .060" clearence to coil bind it broke. All 8 of my exhaust valves hit the pistons somewhat. Im guessing I was having valve float for a while without realizing it and finally the number 8 spring just had enough and broke. I would suggest NOT buying the cheapest springs you can find like me lol. Now I am paying for it! These were the .535" $16 Speedway Motors springs. I have used them on 3 different motors, maybe time took its toll on them also. Thanks, guys!