OK so I am definitely not an "Engine Builder"

I'm also not retarded, so I'm putting my 302 together. I got 6 of 8 pistons in today, no problems. The motor spun freely everything was looking good. I put number 7 in and torque the rod cap, try to spin the motor to get ready for 8 and it won;t spin. Help me.

Please ask any dumb question you can think of as to what I did wrong or what the problem could be. I'll try to answer a few off the bat now. Freshly ground crank .010/.010, bearings are the correct undersize, torque spec is right. I used ARP ***embly lube on the bearing faces and white lith grease on the back, the piston slides well in the cylinder, without the cap torqued the motor turns, I give up. (for now)

I'm thinking of pulling all the pistons back out and having the rods resized just to be sure. I'd rather not pull the motor back apart, but obviously will if need be. I haven't forced anything so I wouldn't do any damage, I just walked away. I say it again, help me.

 

Did you use plastigage to check your clearances?

 

Check to make sure that rod bearing is the correct size...not unheard of to get one in a box that's not. If it is, how much do you trust your machine shop? Temporarily swap that rod/piston into another hole and see if it still binds up. if not, they might not have gotten that crank throw the right size. You shouldn't ever ***emble an engine without measuring...Plastiguage isn't the best way to measure clearances, buy it's better than nothing!

 

No but that is my next move as recommended by a friend. Could the clearances be off even though everything is "new?"

 

I didn't check that particular bearing but I will. I didn't think of it at the moment and like I said I just walked away. The other piston on that journal fits just fine, is it possible that the journal is off from one side to another? I've put motors together before but I am by no means an expert.

 

Got the rod and cap facing the right way?
You know, to clear the fillet on the journal.

 

The rod cap may be on the rod backwards.

Dan

 

Make sure the rod is on the piston the right way. The bearing is chamfered and maybe spaced over slightly to clear the radius on the rod journal. I would bach the rod bolts off and snug them up a little, then turn the crank maybe 1/4 turn. Then pull the cap and look at the bearing for rub marks. May have something behind the bearing too.
Jeff

 

I vote for a reversed rod cap 1st, and the wrong size bearing second.

 

Great minds think alike!

 

I hope the rod caps were kept with the rods and not mixed up. Resize of rod is not the problem or answer. The area between bearing and cap is a dry area with no lub. Cap on backwards will do it to. Don't get bent out of shape yet it is just time to slow down and ****ize the problem.

 

Also you might check to see if by some odd chance there is some piece of grit or shaving between the back side of one of the bearing halves amd the rod bore. It doesn't take much to make a bearing lock up if there is anything to distort the bearing shell and take up the clearance.

Frank

 

#1 Reversed rod cap, #2 wrong clearance, #3 oil ring rail folded up between the piston and cylinder wall.

That last one really ****s, especially to get back out. Sometimes I just hate 3 piece oil rings.

If you want to try that rod on another journal, I would stick it on another throw without putting the piston in a bore. A pain, kinda dangerous as you don't want to drop the piston and F it up. For that matter you could try it on the same journal and determine if it's piston or rod. Might save you having to pull a piston back out.

 

Another vote for a reversed rod cap. Did that on my first build. Never happened again.

 

There are 'right' and 'left' piston/rod ***emblies. I bet you've got one/some swapped and the chamfer on the rod is not facting the fillet on the crank pin and its digging in.

Start here...read lots

http://books.google.com/books?id=1T...6qeJ&sig=rCFUC-stzOrujX-Klm-gLv7shvk#PPA70,M1


-Bigchief.

 

I'll double check the reversed rod cap. As far as I know, the rod has the number stamped on one side and the cap has it stamped on one side. They should be on the same side installed. Thinking back, I'm not sure the pistons are in the right cylinders. I think I may have reversed the opposite bank. Instead of 5-6-7-8 front to back, I think I may be 8-7-6-5 front to back.

Dammit, I'm just gonna stick to paintwork. To anyone in the NJ area: come put this motor together and make it run and I'll paint your ride for free.

 

OK second thing I thought of. When I installed the left bank, 5-6-7-8, the stamped numbers on the rods faced towards the outside of the block. On this side, they have been facing towards the inside of the block. Could my machine shop have f'd up when they installed my pistons? That might cause the illusion of a reversed cap when actually the entire rod is reversed.

 

The rods on a 302 are numbered 1, 2, 3, 4 on one side 5, 6, 7, 8 on the other. #1 is always the first rod to the front of the crank. You can swap them any way you want as long as you have the rod in the correct side. You stamp the rod before you remove it so it wouldn't be stamped on the cam side. If you think the rod may have been stamped wrong go by the bearing tangs. At the shop I have notes where I kept track how the rods go on the pistons otherwise I could tell you. I havn't done any SB Fords for so long I can'nt remember. Get a good service manual out and check it out.

 

Sometimes shops with 'Chevy on the brain' ***emble the Ford rods/pistons incorrectly. Double check everything.

-Bigchief.

 

Are the small ends of the rods a little blue where the heated them to install the pistons? Man if they didn't put the rods on in a press that could be a real *****!! Hard to get the pistons off the rods and not trash the piston without a fixture. And I won't press a heated rod off with my fixture because they come off HARD. Found that out the hard way after damaging my fixture.

 

Roger is right.
You do NOT put anything on the backside of the bearings.
Have you ever heard of spinning a bearing?
Don't give it a head start by lubricating the backside of it.
Take it all apart and start over.
Wipe everything off with a paper towel.
Insert the bearings and put a heavy oil on the bearing surface.
Use OIL on the bearings, not ARP moly lube.
ARP lube has grit in it. THREADS ONLY.
The camshaft needs Moly based paste [with out grit]on it if its a flat tappet.
Prime oil pump with a drill and start engine.
Keep RPM's up past 3000 to break in camshaft.
Matt
Pro-Formance Specialties
1115 East Main St.
Rochester, NY 14609
585-288-1499

 

Let us know the verdict. I am siding with the cap placed backward crowd cause it is easy to do. Been there done that on a 350 buick.

 

my first 302 i put together, i actually revesered a rod cap and then when i figured that out when i got to number 7 it was doing everything your is and it turned out when i tightened down the rod cap the hole for the arp stud deformed and locked the bearing to the crank. Being a cheap SOB i pulled the piston and took my dremel and fixed the offending bump. Motors has been going strong now for 5 years

 

You have got all the great responses I can think of. Why are you using white grease on the metal bearing shells? Or, maybe I don't understand what you meant?

 

"To anyone in the NJ area: come put this motor together and make it run and I'll paint your ride for free."

Where are you located? I'm in Hillsborough, NJ. I'd be willing to help.

 

Hey, guys, Bill was in my shop all day today, helping us blocksand the "Kart", so he hasn't been able to get online today, I'm sure he will check in with you tonight!

Thanks again Bill, you've been a BIG help to us in getting it done for Detroit!

 

Another trick I use in bearing installation is to put the "Tang Slot" side of the bearing in first and even with the bock or rod surface , which ever you are putting in , then with the tang slot in place , slightly ( very slightly ) push the bearing inwards to keep from just jamming it downwards and s****ping material from the back side of the bearings that I have watched many engine builders do . Depending on the type of bearings used , I buff the coating used for shipping the bearing to resist corrosion during shipping off with a clean paper towel or a new red rag until I have a shiny bearing surface , then I lube my bearing . I have torn down engines with full eat out perfect fingerprints on the bearing surface where the ***embler pushed the bearing down with bare hands and the acid in your system with eat at the material even after it's lubed . Just the little help I can give but I agree with the rod cap on backwards . We call it a light side and heavy side of the rod where I come from but it's the same difference .

 

I would take the piston back out, clean the paste and oil off it .Look at the undersize marks on the bearing.Make sure that is correct. Put the bearing in dry on the backside. Lightly lube the bearing surface. Make sure the tangs on the bearings match up top and bottom and match the other rods. Bolt the big end back on the journal and snug it up .You shouldn't have to put the piston back in the hole for this . See what you got. If it won't turn, then you've got an incorrectly marked bearing or a rod or crank machined wrong.

 

I am the ****. I'll pull it apart when I get a chance, prolly won't be for a month or so. My stuff gets back burnered before anything else.

The Kart needs by paint by Saturday god dammit!