End of last summer my 60 Rambler wagon blew a piston, straight 6 cylinder 196, motor still in car. Got a replacement and decided to pull 'em all and replace the rings. Cleaned up everything, de-glazed the cylinders, after installing 3 pistons I can't turn the motor to position for the next 3. I torqued each piston connecting rod to spec (30ftlbs) as I installed it. Dropped some Marvel Mystery Oil in still no luck. This is my first overhaul to this extent. I studied up for this and everything has happened the way it should, up to this point, without forcing anything. Is it correct procedure to torque the bolts on the connecting rods all the way, or should I have left them a little loose to get some torque while spinning the motor by hand (it was smooth and free before re-installing pistons)? Thanks for any advice.
Torque as you go is a good disclipine. After each, turn it to make sure it turns free. Plenty of white grease on bearings on ***embly. YOu prolly have a bearing binding/offset. Did you check ring end gaps, ring off the piston in the hole? Might have a ring binding. Loosen up until you find the culprit.
Sounds like you didn't match the connecting rod caps to their matching rods and/or you put them on backwards.
double check that you got all the rod caps on the correct rods, and pointed the correct way. You did stamp the rods and caps with matching numbers 1 thru 6 before you took it apart?
Whenever putting a motor together, always roate your crank at least a full turn after installing each piston/rods ***embly. You will note it gets a bit harder to turn each time due to increased friction. If something binds or goes in wrong, you will know it was on the last hole you worked and and you can recheck what you did to see what is wrong. Good luck and I hope it is not anything serious. Steve Barcak www.pontiacheaven.org <DIR>Hosting 11th annual Pontiac Heaven, show, swap, drags, party and all around good time. Saturday April 4, 2009 at Speedworld near Phoenix, Az Also hosting- 7th annual Nostalgia drags, show and swap coming Sunday April 5, 2009 to Speedworld. Phoenix, Az </DIR>
What about plasti-gauging the clearances? Like 29Nash says, loosen each one individually up until you find the culprit - this way you can eliminate them one at a time. If this doesn't work, I'd start with number 1 and loosen it, then do number two, then three... etc.
hard to tell from the picture , did you remove the ridge on the top of the cylinder walls? maybe the new rings are hitting the ridge are they new rod bearings , or the originals?
Also did you check to see you had end clearance on the rings by putting them in the cylinder before installing on the piston? Are the bottom of the rings grooves clean,rings below the piston face when pushed down by hand. Correct size rings for the bore? ie. standard bore std. rings. I always install one rod/piston ***y. torque it and then turn the engine one full turn. That way you will [A] not miss torquing one and if there is a problem you will know that it is the one you just installed.
i agree with the whole backwards cap or complete rod in backwars. or maybe you are not calibrating your tourqe wrench correctly and getting them too tight. do you have a pro. wrench or one of those cheepy kind where you watch the giant needle. if so throw it away. and on the other hand double check ring clearence and thickness make sure they gave you the right rings. and check the gap to see if they need grownd if this sounds greek maybe you should have a pro look at it. does it not turn at all or just very tough to turn?
Everything's matched, but I'll admit I'm not sure if the caps are facing the right way. They're factory stamped on one side with a dot, thought that would indicate front, not covered in original manual. Rookie mistake not to check that when removing pistons. Torque according to manual is 27-30. Automatic, spun very easily with no pistons. Using ***embly lube. Didn't remove motor because no apparent need to replace or service cam. Original rod bearings, appeared very clean and re-usable. No, I didn't check ring-gap, trusted them out of the box, will do that first thing. Will take the advice to backtrack, spun with increasing resistance 1st 2, locked on the third, will start there. Working outside, will get back at it in the a.m. Thanks for all the super-fast replies!
First thing you learn in a machine shop is not to trust ANYTHING out of the box. You may want to give the hone another couple p***es, try for about 120 degree cross hatch.
first post but saw this thread first today and i was just there. in my engines cl***, a kid ***embled a motor and it was locked down, i had to make it work. i agree with the guys uptop. if you put a rod in backwards, the sharp edge where the rods ouch on the journal will dig into the fillet on the crank. one side of the rod has a recess machined to match the fillet. the other is 90* with the bearing flush with the rod. good luck man!
Just went out and looked more carefully at remaining pistons. Damn, I put the caps on backwards. So tomorrow morning I'll pull 'em, check the ring gaps, put them on correctly and post results here. Thanks EVERYONE for the great advice and help. -- Johnny
The trouble is, most eyeballs aren't calibrated in thousandths of an inch. I usually borrow a micrometer. Plastigage is better than nothing, but not by much. I know bearing cost money, but you're at a point where you've done a lot of work that you probably don't want to repeat during your lifetime, on that motor... Using the piston upside-down, push the ring down into the cylinder. Then measure the gap.
You have to clean the ring grooves! As the old rings have worn, they expand ever so slightly outward and carbon takes its place. You install new rings with original thickness... they are bound up by the carbon buildup when you put'em back in the hole. Take an old ring and break it intwo. Use the factory end of it to s****e out the ring groove untill you see aluminum. It works! -Mike
You've found the prob...but ****ysis 101: You messed with two things...rings and rods. Rods easiest place to start, so loosen all caps a couple turns and try to rotate engine. If it goes, you look closely at rods... If it didn't go, ring issue like wrong size ring bottoming out or such. Backtrack through all you touched, trying to figure easiest way to take one thing out of the ****ysis.
I almost hate to bring this up at this late date. I think all of us here understand the "Quick and dirty" method. What I'm worried about is that this engine is being rebuilt in place. We do what we have to do. But cleaning the bores and putting a cross hatch in them is going to leave all sorts of abraiseive grit inside that engine, and down on the crank. What's done is done, and it's enough to know the "right" way to do it, even if money or time doesn't allow it. Be sure, take some extra time, to get as much of the dirt and grit off that crank before you tighten down rod caps. Pieces of grit you can't even see could spell death to your hard work. Engine rebuilds have been done this way since there were engines, and can be truly successful, if every thing goes just right. When I was in the machine shop at NAPA, we rebuilt a nailhead and siezed it up with three pistons in it. Somehow, a piece of grit got past us and ruined a journal bearing. We couldn't see it, but it was there anyway. Get it as clean as you can possibly can. Best of luck, Mike
I studied up and everything !! Evidently not quite enough. It's not rocket science just pay attention and re***emble in the reverse order of tear down. That's how the MOTOR manual says to do it . "TO ***EMBLE REVERSE PROCEDURE OF TEAR DOWN" !!>>>>.
Like Mike Britton said, grit will be an enemy after this build. Might be a bit of overkill, but I would change the oil and filter after 5 minutes of run time, then again at 10-15 minutes, and then after an hour - just to be on the safe side. Use a good quality filter - no Fram filters according to some of the carnage we've seen on here in the recent past. I'd change it again at the 50-100 mile mark as well. Some might disagree, but this is what *I* would do and have done in this type of situation.
Wow, sorry Dad. The 'studied' comment was my way of saying I've done the best to my apparently very limited ability, before going to the HAMB for help. I understand the grit issue, cleaned with mineral spirits and compressed air. But will do the 3 oil change/filter method described above. I'll never rebuild like this again, too much h***le, and I understand the value of having the motor removed. It's spinning fine now, by the way. Thanks for all the help.
Nothing wrong with doing it that way. I have done a dozen or more that way with no problems. In the 70s I was changing rods and pistons in the Pintos in the car 2 a day, Rods had no oiler whole and it would scuff the piston. Ford sent us .003 over size (no not .030) and we would hone then spray the cylinders with brake cleen and lube every thing and install. Nary a problem
TooManyFords is right. Nothing WRONG with doing a rebuild in the car, but in the long run it's just as easy and much cleaner to pull it, and then you get to replace that rear seal that will surely start leaking in about a week. Thanks, Mike
It was common practice to rehone and even rebore inline engines in place, back in the day. The chips, etc. go straight down and are easily cleaned. You can have bad technique, however, even if the engine is out of the car. I remember once visiting an engine rebuilding shop, and watching the employees flick their ashes inside the engines they were ****oning up. On the one hand, a few cigarette ashes should not hurt anything, but a bad at***ude is a bad at***ude regardless.
Actually that's a MISCONCEPTION The typical "clicker" type torque wrench is good for +/- 4% accuracy. An equal quality Beam Deflector torque wrench is good for +/-2% accuracy. When your clicker type wrench is out of calibration you have no real way to tell - when your beam deflector is "out" you can see it doesn't go back to zero. SOMETIMES those "caveman" tools are pretty darned good. One could argue that there are even better torque wrenches - those load cell types - and I wouldn't argue that except that I can't afford them AND if I need that much accuracy I probably should be embracing a better way than torquing a bolt!!!
Let me start by saying I'm no expert, but I've been given tips over the years. A technique I've been given is to always lubricate the threads before "torque" is applied to a nut. I use one of those fancy clickers. Alas, I'm always the last to hear about modern methods, so it was educational to find that torque on a nut is the old way, and the new way is tension on a bolt (the new way is now about 50 years old). "Torque must be applied to tension a bolt" Here's a good article: http://www.carcraft.com/techarticles/116_0609_using_rod_bolt_stretch_tool/index.html
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