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Topic Review (Newest First)
08-18-2012 11:05 AM
ryan v i know they are trying to help me. i've got my grandpa helping me now i didn't have him helping me at first. i swapped the rod that was damaged out with one from another complete engine i had laying around. I don't need to buy a used short block because we have about 10 or 15 complete engines in trucks and cars scattered around the farm. lol
I agree bout the sound of a new engine coming to life.
08-18-2012 09:31 AM
vinniekq2 ryan, dont defend yourself,the guys here are trying to help you.If you ruined a rod,just buy a used short block or good core.Pay someone to watch you assemble the engine.Its a lot cheaper to learn the correct way than to replace the broken parts.If that rod let go on a fresh rebuild and windowed your block then all that would be left might be the intake and water pump,,,We all are still learning and we share our experiences both good and bad.

Nothing beats the sound of a fresh engine coming to life especially after doing your own assembly.
08-18-2012 08:56 AM
ryan v I got the crank in and plastigaged it it checked out fine. This isn't the first engine i've rebuilt its just the first sbc i've rebuilt. The last engine i rebuilt was out of 4430 deere. That was a lil different compared to this. I just got in to much of a hurry and didn't think some things completely through on this one but sometimes you gotta learn the hard way. Beleive me my granpa already gave me an ear full for not marking the connecting rods.
08-17-2012 10:10 PM
Crankshaft won't turn by hand

There are alot of mistakes happening assembling your engine. First install the main bearings in the block with assembly lube. Then install the main bearings in the main bearing caps with assembly lube. Look closely the caps should be marked 1-5 with an arrow to the front of the motor. To check clearances just cut a piece of plastic gauge the length of the width of the caps. Wipe the areas clean where plastic gauge is to be used. Torque the caps to specs, do not rotate crank. Loosen the caps and use the gauge paper to see what you have. This can be done one cap at a time. If everything is in spec torque all the main caps and spin crank over. Next lay out all the rods and pistons. Look at the big end of rods. Notice one side extends out more than the other side. These extended ends of the rods face each other when installed in the block. See picture for piston and rod assembly: Piston and Rod Assembly. The rods and pistons should be marked for each cylinder. If not marked and have been mixed up, they will have to go to a machine shop. They can put the rod and caps together and maybe match them. If not they will have to be resized. Once the pistons have been assembled to rod, install the pistons with the dot on top of piston facing front of engine. On the replacement piston measure from the center of the pin to top of piston and measure across the bottom of skirt to see if both pistons are the same. If you can, weigh each one too. Once the pistons are installed it will take a breaker bar and socket to turn crank over. If you do not have a press you will not be able to remove the pin from the piston and rod. Sometimes even at the machine shop the piston breaks when pressing the pin out.
08-17-2012 08:14 PM
PatM I fear you may have impacted the heat treat, hence the strength, of the rods with the torch. I would not try to go throw some mud. I'd get a set of rods, and have the pistons swapped by a shop with a proper facility to properly induction heat the rods. Just me though.

08-17-2012 05:02 PM
ryan v Well i gotta learn how to do it somehow and i don't have the money to take it to a machine shop. I used a torch to heat the connecting rod and slid the wrist pin in by hand.
I had the company i ordered the kit from send me another piston that was the same brand and part number. When i got it it was the same part number. The difference was the the pistons from the set i had a part number of H345acp/H645acp the piston they sent me only had H345acp stamped on it. They are sealed power pistons.
08-17-2012 04:50 PM
Originally Posted by ryan v View Post
I also have a question about the pistons i'm using. I messed one up when i was putting it on the rod. So i ordered a new piston thats the same part number but where the wrist pin goes in it's different. The difference is that one has a full circle of raised material around it and the other only goes about 3/4's of the way around. Would this make a difference in the weight or will it run fine?
I think this motor needs to go to the machine shop. First you mixed up a few rod caps, then you messed up a piston and replaced it with ?????How did you put the others on the rods? 20 ton press? Engine assembly is not rocket science, it is however technical. Most anyone can change a tire, but engine assembly? Best left to someone who knows what they are doing.
08-17-2012 04:45 PM
Originally Posted by S10 Racer View Post
I'm not saying use a 5 lb. beater but a small ball peen or dead blow.
I'm sorry but i have to disagree too. Not a fan of using a hammer on anything engine related.
08-17-2012 04:36 PM
S10 Racer
Originally Posted by vinniekq2 View Post
DO NOT smack any rods with a steel hammer,lol.
I'm not saying use a 5 lb. beater but a small ball peen or dead blow.
08-17-2012 11:26 AM
ryan v I also have a question about the pistons i'm using. I messed one up when i was putting it on the rod. So i ordered a new piston thats the same part number but where the wrist pin goes in it's different. The difference is that one has a full circle of raised material around it and the other only goes about 3/4's of the way around. Would this make a difference in the weight or will it run fine?
08-16-2012 09:44 PM
vinniekq2 make notes of all clearances as you build it. make it as perfect as you can afford,then go fling some mud
08-16-2012 09:29 PM
ryan v i wouldn't say high performance. its just a mild motor for my mud truck only gonna be ran a few times a year.
08-16-2012 09:16 PM
vinniekq2 DO NOT smack any rods with a steel hammer,lol. Is this a trial fit of the parts? an engine is usually fitted a couple times,crank hand polished, you will need to or should check side to side clearance on rods, piston to wall should be individually checked,,etc,,, is this in any way a high performance engine?crank end play,,,
08-16-2012 09:03 PM
ryan v i didn't mark them but i laid them out in order. i didn't have them resized. i'm not even sure if there is a place within a couple hours of here that resizes rods
08-16-2012 08:56 PM
FmrStrtracer Did you mark the rods and caps when you removed them during teardown?
Did you have the rods resized?

If you didnt keep the rod caps with their original rods, then you should have all the rods resized so the bearing crush is correct and your clearences arent wrong. Bearings are not supposed to be "worn" in, if the clearences are too tight or too loose, you will have damage on startup.

Did you clean the crank after you got it back from the machine shop. Never trust that everything has been cleaned from the oil holes, some shops only blow the outside of the crank off, and leave shavings in the oil holes, expecting that the customer should know to clean the crank before installation.

Are you installing the rod/pistons in the right dirrection, they have markings to show which side should face the front of the motor.
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