Slant Six Forum
https://slantsix.org/forum/

HELP!!! New Engine Scare!
https://slantsix.org/forum/viewtopic.php?t=21122		 Page 1 of 1
Author:  vynn3 [ Sat Dec 16, 2006 2:18 pm ]
Post subject:  HELP!!! New Engine Scare!
To update: I've been installing my rebuilt long rod slant over the past few weeks. I'm almost ready to start her — I was shooting for tomorrow, since the weather is going to turn again on Monday.

I had the short block professionally assembled, and I put the rest together myself. The engine spun freely using a crank bolt and a torque wrench. After installing the crank pulleys and tightening the balancer until I couldn't tighten it without turning the engine over, I noticed the pulleys didn't line up with the water pump pulley. It was about a 1/2" too far out. No biggie, I used a trick I read somewhere and inserted a length of soft nylon rope into the #1 spark plug hole to prevent the #1 piston from reaching TDC. That and a few washers on the crank bolt allowed me to tighten the balancer/pulleys to the point that everything lined up. Cool.

The problem is, now that I removed the nylon rope, the engine won't turn over by hand! No spark plugs are installed, and nothing I can think of has changed since I installed the balancer. I keep cranking on the crank bolt, and it just keeps getting tighter and tighter. I'm afraid I'm going to strip the end of the crank, and I KNOW the engine didn't need this much muscle to turn over before.

I'm TERRIFIED that I've screwed something up! I put a LOT of $$$$ into this rebuild, and I'm depending on the engine to run! Please, please, someone tell me I've overlooked something simple and I haven't just cost myself more money I can't afford. I'm on the edge of a panic attack!
Author:  GTS225 [ Sat Dec 16, 2006 5:03 pm ]
Post subject: 
I think I'd try installing the flywheel or flexplate, and attempt to spin the engine over in reverse rotation, then see where you are at. It may just be something got a little "jambed up", so to speak.
Can you say with absolute certainty that a strand of rope didn't get wedged between the cylinder wall and the top of the piston?
You might have to pull the head back off and do a visual inspection.

Roger
Author:  slantedview [ Sat Dec 16, 2006 6:11 pm ]
Post subject: 
Try pulling the pushrods for the cylinder that you put the rope in and see if it'll turn over. You may have a strand of rope hung in a valve. If the engine does or doesn't turn over, you are still going to have to pull the head and clean out the crap. Next time, use cotton clothesline instead of nylon, or even better, a piston stop you screw into the sparkplug hole. I've had good results with both. :wink:
Author:  sandy in BC [ Sat Dec 16, 2006 6:23 pm ]
Post subject: 
Did you pull the crank forward with the pulley till it is locked in the mains? Try turning it backwards using the fly wheel.....or take off the damper and see where you are at.
Author:  SlantSixDan [ Sat Dec 16, 2006 6:41 pm ]
Post subject: 
Quote:
Try pulling the pushrods for the cylinder that you put the rope in and see if it'll turn over. You may have a strand of rope hung in a valve.
H'mm. How would that stop the engine turning over, if there were anything holding a valve open? A stuck-open valve can't stop the engine turning, as it seems to me.
Author:  slantedview [ Sat Dec 16, 2006 7:16 pm ]
Post subject: 
Quote:
Quote:
Try pulling the pushrods for the cylinder that you put the rope in and see if it'll turn over. You may have a strand of rope hung in a valve.
H'mm. How would that stop the engine turning over, if there were anything holding a valve open? A stuck-open valve can't stop the engine turning, as it seems to me.
It will if a loop of rope is wrapped around both valves and one is closed. Had that happen to me one time when I tried this trick with 3/8" nylon rope. Dug out almost 6" of rope. Sandy in BC has a good point too.
Author:  vynn3 [ Sat Dec 16, 2006 7:23 pm ]
Post subject: 
FYI, took a dinner break and thought about my problem, and came up with a theory: What if I was lining up the wrong pulleys, and had the balancer bottomed out against the main? The crank has three pulleys, one of which was for the factory A/C removed several years ago.

So, I pulled out the balancer puller, backed it out an inch or so, and, lo and behold, the engine turns over again! I'm trying not to think about the possible damage I could've caused by my overtightening. I guess that's why guys like me should pay someone else to do the stuff like this. Regardless, at this point I ain't yanking the engine back out and pulling it apart to check it out. I'm just praying everything is okay...

Thanks for the responses, and wish me luck. I'm still shooting for a start by EOD tomorrow!
Author:  Charrlie_S [ Sat Dec 16, 2006 8:21 pm ]
Post subject: 
There is no way, drawing the damper on with the crank bolt, could jam the engine. The damper bottoms against the oil slinger (if used), the timing sprocket, and the sprocket seats against a step on the crank. I would check the bolts that hold the pulley to the damper. If they are too long, and stick out the back of the damper, they could jam against the timing cover, when the damper is on all the way.
Been there, done that.
Author:  LUCKY13 [ Sat Dec 16, 2006 10:19 pm ]
Post subject: 
Quote:
There is no way, drawing the damper on with the crank bolt, could jam the engine. The damper bottoms against the oil slinger (if used), the timing sprocket, and the sprocket seats against a step on the crank. I would check the bolts that hold the pulley to the damper. If they are too long, and stick out the back of the damper, they could jam against the timing cover, when the damper is on all the way.
Been there, done that.
Good piont Charlie, I have done the same and I bet it is what he has done. The bolts (pulley bolts) simply dig into the timing cover. Check the front seal if this is what happened, I aint sure but the bolts may line up with the seal and damage it. Pull the balancer all the way off and it will be noticable if it is the problem.


Jess
Author:  AnotherSix [ Sun Dec 17, 2006 9:26 am ]
Post subject: 
If the bolts were hitting get the right length bolts and put the balancer back on all the way. They are not supposed to be a floating press fit. Also the rope trick is to keep valves from falling in while removing the springs, not to keep the engine from turning. You could easily bend an open valve, pushrod or rocker by jamming the rope against it with the piston while torquing on the crank. If you use the rope for holding the valves, melt the end that goes in so you do not lose some of it and have it end up between the piston and bore.
Author:  vynn3 [ Fri Dec 22, 2006 4:30 am ]
Post subject: 
Okay, to sum up: new balancer front pulley bolts were too long, and they'd bottomed out against the timing chain cover. I pulled the harmonic balancer to check for damage (just a three paint scratches on the timing chain cover). Now, during the process of pressing the balancer back on with the crank bolt, at least the first few threads of the crank have gotten cross-threaded.

I bought a new crank bolt to make sure it wasn't the bolt (the first few threads of the old bolt had gotten buggered uo, too). The new bolt bites for a thread or two, but it looks slightly crooked, and it tightens up and comes off with pressure.

Am I screwed? I can't imagine finding an appropriate tap, and getting it perfectly lined up with the old threads. Nor can I see drilling out the hole and retapping the crank.

I'm just sick.
Author:  argentina-slantsixer [ Fri Dec 22, 2006 4:38 am ]
Post subject: 
Quote:
Okay, to sum up: new balancer front pulley bolts were too long, and they'd bottomed out against the timing chain cover. I pulled the harmonic balancer to check for damage (just a three paint scratches on the timing chain cover). Now, during the process of pressing the balancer back on with the crank bolt, at least the first few threads of the crank have gotten cross-threaded.

I bought a new crank bolt to make sure it wasn't the bolt (the first few threads of the old bolt had gotten buggered uo, too). The new bolt bites for a thread or two, but it looks slightly crooked, and it tightens up and comes off with pressure.

Am I screwed? I can't imagine finding an appropriate tap, and getting it perfectly lined up with the old threads. Nor can I see drilling out the hole and retapping the crank.

I'm just sick.
most cranks that weren't suposed to use crank boltd for holding the damper there (like our /6's) have poorly cut threads and shallow bolt hole. Mine takes a 3/4 SAE x 1.25" bolt, ather I carefully recuted the threads using what we call a "thread comb" for restoring damaged threads. Those damaged threads comes, most likely, from poor quality damper pullers.
Author:  emsvitil [ Fri Dec 22, 2006 5:23 am ]
Post subject: 
You can make a sort-of-tap with a sacrifical bolt.....

grind some metal off it so it looks like a self-tapping screw.

goto mcmaster carr (www.mcmaster.com) and look at their pictures of screws if you're not sure of what I mean.
Author:  Jeb [ Fri Dec 22, 2006 6:13 am ]
Post subject: 
Taps for these things are easy to find. Mine stripped out during damper reinstall also. Just go down to your local hardware store and pickup a 3/4 X 16 UNF tap. Mine costs $14 at Ace hardware.
Page 1 of 1 All times are UTC-08:00
Powered by phpBB® Forum Software © phpBB Limited
https://www.phpbb.com/