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Discussion Starter #1 (Edited)
Is it possible for me to relpace my connecting rod bearings with out me having to rebuild the whole engine, or better yet pull it out agin which i'd really like not to do? I was thinking of replacing them along with new rings, just to freshen up the engine for the rest of the year until I drop my worked 351 in the spring. Now when I put my rings in, should I hone the cylinders, and what would be the correct way of doing it...I forget. One of the rods knocks a bit when I match the throttle to the speed of the car. Anyone have any advice for a limited budget? I've seen the "summit freshen your engine kit" and was considering this route along with the summit canshaft. Thanks


PS...I blew a whole through the top of my #2 piston in my 89 bronco's 302. Can I just replace the piston, or do I have to replace them all? I can definately do it with the engine still in the truck, If I lift it 4 inches, but I just wanted an opinion before I rlace the one piston. Thanks
 

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Rod Knock

If you have a rod knock, it would probably need crank work. May as well wait until you can pull the engine and completely rebuild it.
 

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Discussion Starter #3
How long can I wait with the rod knock like that, because I fi'm going to rebuild a motor I want to do the 351 the right way. I mean the knock is that bad. Only does it when the engine warms up. I guess when the oil thins a bit. I also use Lucas oil treatment, and that seemed to help alot. i wonder if a new hi volume oil pump would do the trick. I notice that when I first start the car when its cold, the oil pressure is at 60psi, and then eventually it drops to about 10psi at idle. at 2000rpm its a 20. Pretty much 10 psi for every 1000rpms. Is that correct? Wouold a hi pressure oil pump be better. I'm trying to figure out if the psi has something to do with it, because again, when the engine is cold at startup, there is no knock, and it only knocks when I take my foot off the gas aliitle and match the throttle to the speed that I am traveling. How much would crankwork go for, and also are there special tools involved for honing out the cylinders one size? Because if I'm going to rebuild this motor, I have to do everything myself to save money fpr the 351.
 

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I just had my 67 390 crank ground down for 95 bucks...main and rod journals. probably around 35 dollars for a polishing only, depends how bad your crank is.
 

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If you are really desparate... Drop the pan and install a new set of rod bearings but don't even touch the top end without doing the crank. I have done this a few times without blowing the motor but it's not going to hold up if you increase the power with new rings and a cam. Pull the pan and oil pump out and do one rod at a time. Make sure you clean the journal real good and lubricate the bearing with oil or vaseline. Torque the rod to factory specs. Of course this is NOT a rebuit motor. You can replace one piston on your 302 but when replacing a piston or rings the head needs to come off and then use a ridge reamer and a hone in the bore before reinstalling. you should think about a rebuild or a replacement motor in both vehicles.
John
wvcat
 
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