I use Casite Motor Honey or STP oil treatment to lube when I assemble an engine...
318 LA rebuild after losing a valve seat
- Thread starter Righty Tighty
- Start date
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I use Casite Motor Honey or STP oil treatment to lube when I assemble an engine...
You guys are gonna think I'm an idiot, but hopefully by me documenting all of this, someone can learn from my mistakes and I'll save some heartache.
I pulled the pistons and turned the crank after each one to feel the resistance. I started with #1 and 2 cylinders, and I think immediately found the problem. The bottom oil ring on each was bent. I must not have had the ring compressor around ALL of the rings, and upon tapping them in, bent the oil ring and smashed it between the piston and cylinder wall. Looking back, on subsequent pistons, I remember the piston sliding out of the ring compressor just a hair, exposing the bottom oil ring. This must have happened on pistons 1 and 2, I just didn't catch it. After removing pistons 1 and 2, the crank was turning better. Luckily the cylinder walls weren't damaged.
Second problem I found was a couple of the caps were reversed. When I disassembled the engine, I marked each cap/rod with a paint pen. Now either I mixed up a couple in the process, or they were like that in the engine. Either way, shame on me for not catching it when I installed the bearings. Here you can see only one of the tangs when both should line up, the the edges are offset.
Now that I'm starting over, I'll clean everything up again and get the plastic gauge out. This time, I'll go slower and drink less beer....
I pulled the pistons and turned the crank after each one to feel the resistance. I started with #1 and 2 cylinders, and I think immediately found the problem. The bottom oil ring on each was bent. I must not have had the ring compressor around ALL of the rings, and upon tapping them in, bent the oil ring and smashed it between the piston and cylinder wall. Looking back, on subsequent pistons, I remember the piston sliding out of the ring compressor just a hair, exposing the bottom oil ring. This must have happened on pistons 1 and 2, I just didn't catch it. After removing pistons 1 and 2, the crank was turning better. Luckily the cylinder walls weren't damaged.
Second problem I found was a couple of the caps were reversed. When I disassembled the engine, I marked each cap/rod with a paint pen. Now either I mixed up a couple in the process, or they were like that in the engine. Either way, shame on me for not catching it when I installed the bearings. Here you can see only one of the tangs when both should line up, the the edges are offset.
Now that I'm starting over, I'll clean everything up again and get the plastic gauge out. This time, I'll go slower and drink less beer....
What is your bore diameter?
I have a set of rings, new in the box minus one piston.
The rings I have are std bore.
I broke a ring installing theme on the pistons on my last build.
Glad you found the problems, you are getting it.
Unfortunately my bores are .040 over at 3.950. Thanks for the offer though.
nm9stheham
Well-Known Member
You can sometimes find single ring sets for purchase. That would explain part of it! Again, use something like oil, not that assembly lube.
BTW.... very important.... in your pix of the reversed rod cap, are the cap bolts snugged down? I ask, as that significant gap showing between ends of the rod bearing halves should not be there. The ends of the bearing halves should butt against each other and slightly crush when you torque the rod fasteners.
Can you put together a rod and cap and bearings oriented in the correct direction and torque the rod fasteners down and look for there to be no gap where the bearing halves meet?
BTW.... very important.... in your pix of the reversed rod cap, are the cap bolts snugged down? I ask, as that significant gap showing between ends of the rod bearing halves should not be there. The ends of the bearing halves should butt against each other and slightly crush when you torque the rod fasteners.
Can you put together a rod and cap and bearings oriented in the correct direction and torque the rod fasteners down and look for there to be no gap where the bearing halves meet?
I used a 50/50 mixture of STP and 30 wt motor oil as an assy. lube.
From post #77 ---- the rod bearings are incorrect. The bearing tangs must be on the same side. The other sides are plain on a 318. The other sides have a V notch on the 340's.
From post #77 ---- carefully remove the oil rings from the piston. See if the outer rings are still flat. You may get lucky.
Keep up the battle.
From post #77 ---- the rod bearings are incorrect. The bearing tangs must be on the same side. The other sides are plain on a 318. The other sides have a V notch on the 340's.
From post #77 ---- carefully remove the oil rings from the piston. See if the outer rings are still flat. You may get lucky.
Keep up the battle.
Wyrmrider
Well-Known Member
good advice
possible more than one problem
dbl check the caps match the rods and orientation
numbers do not have to match the cyulinder but valve notches in the pistons do
after you get them in roll the motor over on the stand and check before going further
and remember
If stuck you must find out why before going forward
righty tighty - lefty loosey
for assembly if you are going to run it reasonably quickly then it does not much matter
long term STP hangs in there FOREVER
remember one very famous ford race blew up like 30 motors before realizing that white grease was the problem
it turns to coke when it gets hot and does not dissolve in motor oil
do not use anything that does not dissolve in motor oil
possible more than one problem
dbl check the caps match the rods and orientation
numbers do not have to match the cyulinder but valve notches in the pistons do
after you get them in roll the motor over on the stand and check before going further
and remember
If stuck you must find out why before going forward
righty tighty - lefty loosey
for assembly if you are going to run it reasonably quickly then it does not much matter
long term STP hangs in there FOREVER
remember one very famous ford race blew up like 30 motors before realizing that white grease was the problem
it turns to coke when it gets hot and does not dissolve in motor oil
do not use anything that does not dissolve in motor oil
Always liked that STP for engine assembly lube. Even like that Lucus Engine Oil Treatment too. These products stick to the parts like honey.
nm9stheham
Well-Known Member
A thread about single ring sets:
273 & 318 single piston ring availability
If you only need the oil ring set, then you could use just about any brand IMHO. I think this will do the job in a single set:
Hastings Premium Ductile Ring Sets 2M148S040
273 & 318 single piston ring availability
If you only need the oil ring set, then you could use just about any brand IMHO. I think this will do the job in a single set:
Hastings Premium Ductile Ring Sets 2M148S040
I have had very good luck using Joe Gibbs Racing assembly lube.
It sticks where you put it and dissolves in oil.
It sticks where you put it and dissolves in oil.
The bolts were not snugged down, only drawn in a bit to bring them together. After correcting the orientation and snugging, they are matched nicely.
That picture was to show how they were incorrectly oriented, I corrected it since then. And those oil rings are garbage. Very much destroyed.
I plasti-gauged the journals, and they all had +/-.001" clearance, well within the .0005-.0020" from the manual. I cleaned the bearings and journals once again, lubed them with engine honey, and installed the first piston. With the cap on but not snugged, it rotates. Once I snug it the very least, incredible resistance. I removed the piston, inspected the rings, all good. I cleaned the honey off and used oil this time. Same thing, so much resistance I can't turn the crank with just one piston in. Or if I can, it's jerky and sticky, and I'm using a LOT of force. Like, the engine stand wants to tip over I'm trying so hard.
I used a micrometer on the journals, and they read 2.109" for #1 & 2, 2.110" for 3 & 4, 2.109" for 5 & 6, and 2.108" for 7 & 8.
OK here is a simple test for you.
With all the pistons out and block upside down. Put one piston and rod on, out in the open with the piston standing straight up. Now with the rod cap snugged up try and rock the rod back and forth to see that it is free on the crankshaft journal.
Betting it is going to be tight.
Wrap a towel around the piston and skirt during this test to protect it so it won't get chipped by accident.
With all the pistons out and block upside down. Put one piston and rod on, out in the open with the piston standing straight up. Now with the rod cap snugged up try and rock the rod back and forth to see that it is free on the crankshaft journal.
Betting it is going to be tight.
Wrap a towel around the piston and skirt during this test to protect it so it won't get chipped by accident.
I actually already did that, and yes, pretty tight. What I don’t understand is while the plasti-gauge results were good, it’s still as tight as it is. Do I need larger bearings?
What I know about plasti-gauge is it is supposed to read between .001 and .003
Ideally you want it to read .002 thousands to represent the oil film on the crank.
So it looks like you are running tight with the pladti-gauge at .001 squishing it out wide.
I usually emery cloth the inside of the rod journal surfaces by hand to make sure they are clean with no high spots, just to clean them not taking off large amonts of material.
See if this helps loosen up one rod journal and try the test again. Does not take much for the bearings to be too tight when you are talking in thousands of an inch.
Ideally you want it to read .002 thousands to represent the oil film on the crank.
So it looks like you are running tight with the pladti-gauge at .001 squishing it out wide.
I usually emery cloth the inside of the rod journal surfaces by hand to make sure they are clean with no high spots, just to clean them not taking off large amonts of material.
See if this helps loosen up one rod journal and try the test again. Does not take much for the bearings to be too tight when you are talking in thousands of an inch.
Talking emery cloth cleaning the actual rod bearing surfaces, not the aluminum bearing inserts.
Just to be sure . . . ^^^^^
Just to be sure . . . ^^^^^
Thanks for the clarification, luckily I assumed you were referring to the journals themselves and not the bearings. I don’t think I want to touch the bearings with anything other than gloved fingers. 
The only other area where things may have went wrong is that a rod bearing cap off of one of the other rods got place on a rod that it did not originally come off of. That will raise heck with the bearings not fitting the crank journal. Definate No No.
You need to be 100 % sure that this did not happen. Otherwise it's back to resizing the large ends of the rods again.
Try rod # 6 for a test fit on the crank to see if that one fits looser. Try to find out if just one or two of them are tight, or if they all are.
You need to be 100 % sure that this did not happen. Otherwise it's back to resizing the large ends of the rods again.
Try rod # 6 for a test fit on the crank to see if that one fits looser. Try to find out if just one or two of them are tight, or if they all are.
For the sake of conversation lets say that you got 2 of the rod caps installed on the wrong rods, let's say rod and piston #1 and #2.
Now let's say that you test fitted all the other 6 rods on the crank journals, snugged up they moved freely. Rods 3 thru 8.
So let's say Rods and bearings 3 thru 8 all fit correctly and move freely.
But Rods #1 and #2 fit tight yet. OK now you have it narrowed down to the problem at 1 and 2 fitting tight. So swap the rod cap from 1 and put it on rod 2, then the the rod cap from 2 snd put it on rod one.
Now test fit the 1 and 2 rods and bearings on the crank journal again to see if they have loosened up and move freely, if so you should be golden.
This test is called "Process of Elimination"
See what you can figure out, see if you can get it freed up.
Before you go much farther, does the rod bearings have a champher on them, for the turned crank?
Something is very wrong with the rod bearings.
Something is very wrong with the rod bearings.
I did correct this earlier, 4 of the caps were wrong. Either they got mixed up at the machine shop, or I mixed them up, or they came off the engine like that. My money’s on the newbie.... (me)
They do have a very slight chamfer, not sure if you can see it in the other pictures. Should there be a more defined chamfer?
Wyrmrider
Well-Known Member
the rod big end machining marks should line up cap to rod
you can match them up
you can match them up
OK let's get this figured out you say you had 4 of the rod caps mixed up. Did you get them back on to the original rods the way they were at the first dissasembly?
I back read on post #77 you also stated that the rod caps got mixed up after marking them with the parts pen.
Need to find out if you corrected this or are they still mismatched ??
Correct, somewhere along the way they got mixed up even after they were marked after disassembly. There were very small stamps on the sides of the cap/rod that I hadn’t noticed before. That’s how I eventually matched them up correctly.
One other thing on your rod bearing assembly to the rods, i install the rod bearings dry into the long part of the rod and also dry inserting them into the rod caps. Don't want that thick STP lube in there giving it a reason to turn a bearing in the future. (spun bearing)
Also slight possibility that thick lube there is making them tight on the crank. As you were saying a few bearings were sticking up .020 ths. proud above the flat surface of the rod cap . . It should be flush.
So anyhow insert rod bearings into rods and caps dry. Then when they are installed flush then apply your STP assembly lube to the bearing face that is facing the crank journal. Then install on crank and snug up and torque.
Also slight possibility that thick lube there is making them tight on the crank. As you were saying a few bearings were sticking up .020 ths. proud above the flat surface of the rod cap . . It should be flush.
So anyhow insert rod bearings into rods and caps dry. Then when they are installed flush then apply your STP assembly lube to the bearing face that is facing the crank journal. Then install on crank and snug up and torque.
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