HELP! New rebuild, engine will not turn.

The bearings go in the rods one way, but the rods go in the engine two ways. Right way and wrong way. How about you rear main seal? Did you do that right? Got plenty of oil on it? Not sticking out to much? Something is hanging things up.

 

The rods were never removed from the pistons and this was the first rebuild for the motor (backside of the bearings were all standard size and stamped Ford) The pistons have notches on top like an arrow and I made sure they all pointed toward the front of the block like they came out.

Oh yeah, I greased up the seal and shaft before I put the seal on.

 

Are you getting consistent readings with Plastigauge? I tried rebuilding an engine using Plastigauge and I wasn't confident in the readings at all. I should have stopped then and regrouped. The engine ended up having a high oil pressure problem: it was high and it would keep increasing with RPM. It came out and has been setting for years. I have no idea if using Plastigauge has anything to do with the problem, but I do know that it didn't build my confidence. One of these years I will take it apart and measure the bearing clearances with more standard tools, better figure out the rebuilding procedure, and eventually try running it again.

Thanks,
Kurt

 

And you have the pistons in the right holes? My manual shows the right bank numbered 1234 and the left bnk 5678. Unlike I would think with most engines. It also shows a lip seal. Don't think that would do anything bad.

 

Rod caps on correctly but the rods and pistons in backwards eliminating the valve clearance and locking up the engine? Seen this done once on a chevy but it would turn till the valves hit the pistons..
Dave

 

Why would you put the heads on before you have the timing chain in place?

Did you turn the engine over by hand before putting the heads on?

That could have told you a hell of a lot.

NOT turning over the engine by hand before you put on the heads leaves you with a whole lot of questions you still need to answer and possibly CAN'T answer.

With the heads off, did the crank turn by hand or by a short lever,
as you were installing and hooking up each piston and rod ***embly?

That gives you some mighty important information you just didn't pay attention to.

You HAD to rotate the crank as you went along in the ***embly procedures. What did it feel like each time you rotated and added another piston and rod ***embly?

Exactly WHEN did things change from an engine you could rotate as you ***embled it, to an engine that could NOT be turned?

Noting WHEN it happened will tell you a lot.

Think back every step of the way, and see if you can take note of when things changed from "positively successful" to "questionable".
There will be one step along the way that you will need to backtrack to so you can make sure the later steps were done correctly.

You WILL NEED TO BACKTRACK all the way back to the point where you know it was still a successful ***embly project.

Every ***embly step after that will need to be repeated as you double check every single step and note exactly WHEN the problem starts.

 

Not that it helps, but a few years ago before I knew any better... I built a 289 that I had a tough time of turning over when all ***embled. It was a ***** to move if it was caught at top dead center and just about as bad anywhere else. Once I got it turning, it would continue to roll over failry effortlessly but if I let it set it would be a *****.

Well, I turned the motor by hand then fired it up. That motor has a ton of miles on it and is still running strong. This was done in 96.

Im sure that it wasnt right, but with no money and little patience I did the best I could and it worked out. I always thought of that situation as the "final machining process" of that motor build!

Good luck with yours.


Rob

 

my experience!!
in 1966 i got 2 weeks leave before going to Nam and took the 53 olds engine down and cut the crank, due to sloppy work it was stuck and I had to wait for a year to get back from Nam, was on my mind a lot along with staying alive!!
got back and when winter ended pulled the olds out of the 53 chev and had a ****ed bearing, what a relief

 

Kurt, this sounds more like the oil pressure relief valve is stuck. Should be an easy fix......

 

While every one is still beating on tight bearings . let's go back to the beginning. You said the heads are on but there is no timing chain. If the lifters and pushrods are installed and you are trying to rotate the engine with valves staying open!!!! Some engines are noninterference engines, but I'll bet yours isn't.

 

I was about ready to load it up and take it to where I bought the crank to get them to take a look, but I just had to give it my best shot one more time.

Long story short, I tore apart and started over. I untorqued each main cap and turned the crank each time to narrow things down. The rear main made the most difference when it was loosened. Same for the 4th main. So I loosened all of them and worked my way from the middle out, one at a time until I narrowed it down to the 4th and rear mains being the tight ones. I pulled all the caps and the cranks to inspect the bearings and all looked well. It was when I pulled the bearings out that I found the culprit. There was some schmutz in the little notches that the bearing fits in the block. Just enough to cause the bearings to ride up a gnat's hair. I carefully cleaned each one and started over on my ***embly. Long story short, its all back together now and turning MUCH better now. I will tear it down one more time to check with mics or plastigauge, but I think I got it licked.

Thanks everyone with some great advice.

I was confident I hadn't gotten any parts mixed up. Say what you will about SBF's, but at least on the newer ones, most of the parts are marked so that you'd really have to be not paying attention to mix them up. Eugene vic got me thinking about the ****ed bearing so I started looking for what would cause it.

Though I might have put together and took 2 or 3 times, I won't forget it and I enjoyed myself. Its been years since I built an engine myself and it was a good refresher.

 

Good news..Its always something


Eric

 

How many thousandths is a "gnat's hair?"

Schmutz is ALWAYS bad **** to have around fresh parts!!

Just remember-- CLEAN is GOOD! CLEANER is BETTER.

 

no timimg chain means that the cam is not turning, and the valves are not opening...you are fighting compression.

 

You learn from your Mistakes, Glad you found it <br> you had a Lot of Good Advice keep it in mind when you do your Next rebuild <br> just my 3 cents