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420A Crankshaft wont turn at all

Kmorrow

Probationary Member
5
2
May 12, 2022
Greenville, Ohio
99 Eclipse RS 2.0L with 420a engine. Car sat for a year due to blown head gasket. Removed the cylinder head to replace gasket but crank won't budge at all. I'm using a 3' breaker bar and still nothing. This is the first time I've personally changed a head gasket and everything has gone smoothly (thanks largely to info here) but I can't get the crank to TDC. Someone please tell me what I'm doing wrong.
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Solution
I don't think its rust frozen. If it were, why are the bores still not rusted to hell? Have you pulled the pan to look at the bottom end? That shouldn't be rusty as thats where all of the oil is.
Are we SURE the rods aren't locked onto the journals of the crank not the cylinder walls, for whatever reason?
I'd take it apart from the bottom end. You'll find why doing it that way. Its more tedious but won't hurt anything.
The pistons were just froze in place. I put acetone / tranny fluid in the cylinders and tapped the top of each one. Numbers 1 and 4 stuck but I got them moving and all cleaned up. Thanks though. I appreciate all the help from the people here.

pauleyman

DSM Wiseman
7,973
2,595
Nov 19, 2011
oklahoma city, Oklahoma
Both directions? Looks like you're headed for a full teardown. I've seen rusty cylinders before but those don't look bad. Certainly not a match for a breaker bar. The car is in neutral I assume assuming it's 5 speed?
 

Kmorrow

Probationary Member
5
2
May 12, 2022
Greenville, Ohio
Both directions? Looks like you're headed for a full teardown. I've seen rusty cylinders before but those don't look bad. Certainly not a match for a breaker bar. The car is in neutral I assume assuming it's 5 speed?
Yes, it's in neutral. And it won't go CCW without the bolt coming loose
 

Kmorrow

Probationary Member
5
2
May 12, 2022
Greenville, Ohio
I agree with Pauley. Doesn’t look that bad. Can you bump the starter?
I haven't tried because everything is torn apart, even the column and ignition. It's a project car. But I could probably put a battery in it and jump the connections
 

TK's9d2TSi

Supporting Member
6,302
3,293
Sep 11, 2017
Cincinnati, Ohio
I haven't tried because everything is torn apart, even the column and ignition. It's a project car. But I could probably put a battery in it and jump the connections
That’s what I was thinking. Just use jumper cables to the starter
 

waltah

Proven Member
305
128
Mar 2, 2011
fairfield, Virginia
With all four pistons at the same height you're in the worst possible situation in terms of mechanical advantage -- the crank journals are all at either 3 or 9 o'clock so your breaker bar puts the least possible force on the piston/cylinder joints for the amount of force on the bar. What I'd try is:

1. Sloosh plenty of WD 40 in each cylinder and let it sit overnight.

2. Cut about a 2" x 2" x 1 foot long chunk of wood, stick it down each cylinder in turn, and give it a smack with about 2# hammer. Don't beat on it -- just smack it lightly at first, then moderately if 'lightly' isn't enough. Doing it this way puts all the force on the frozen point between the cylinder and the piston with almost none to the bearings. Try with the breaker bar after each cylinder is smacked -- might be only one is stuck.

There is of course a slight risk of breaking a ring. But I bet things will free up without anything bad happening and if you can't move it with everything together you'll likely have to do something equivalent to get the pistons out as part of a teardown, anyway.
 

Kmorrow

Probationary Member
5
2
May 12, 2022
Greenville, Ohio
With all four pistons at the same height you're in the worst possible situation in terms of mechanical advantage -- the crank journals are all at either 3 or 9 o'clock so your breaker bar puts the least possible force on the piston/cylinder joints for the amount of force on the bar. What I'd try is:

1. Sloosh plenty of WD 40 in each cylinder and let it sit overnight.

2. Cut about a 2" x 2" x 1 foot long chunk of wood, stick it down each cylinder in turn, and give it a smack with about 2# hammer. Don't beat on it -- just smack it lightly at first, then moderately if 'lightly' isn't enough. Doing it this way puts all the force on the frozen point between the cylinder and the piston with almost none to the bearings. Try with the breaker bar after each cylinder is smacked -- might be only one is stuck.

There is of course a slight risk of breaking a ring. But I bet things will free up without anything bad happening and if you can't move it with everything together you'll likely have to do something equivalent to get the pistons out as part of a teardown, anyway.
I was wondering if they should be all at the same height like that or not. I've actually had it soaking in a 50/50 mix of acetone and transmission fluid for about a day and a half. I'll try to free up the pistons with a block of wood tonight

Got it! Thanks!
 
Last edited by a moderator:

waltah

Proven Member
305
128
Mar 2, 2011
fairfield, Virginia
I was wondering if they should be all at the same height like that or not. I've actually had it soaking in a 50/50 mix of acetone and transmission fluid for about a day and a half. I'll try to free up the pistons with a block of wood tonight
All four same height near mid-cylinder is fine. Now I've got an engine with three near the top and one at bottom: That's not so fine. Further study will find the hole in the crankcase poked by that rod. A 4g93 1.8L engine that came in an Expo parts car.

Good luck with it!
 

1990TSIAWDTALON

Moderator
9,128
4,963
Nov 14, 2013
Independence, Kansas
I don't think its rust frozen. If it were, why are the bores still not rusted to hell? Have you pulled the pan to look at the bottom end? That shouldn't be rusty as thats where all of the oil is.
Are we SURE the rods aren't locked onto the journals of the crank not the cylinder walls, for whatever reason?
I'd take it apart from the bottom end. You'll find why doing it that way. Its more tedious but won't hurt anything.
 

Kmorrow

Probationary Member
5
2
May 12, 2022
Greenville, Ohio
I don't think its rust frozen. If it were, why are the bores still not rusted to hell? Have you pulled the pan to look at the bottom end? That shouldn't be rusty as thats where all of the oil is.
Are we SURE the rods aren't locked onto the journals of the crank not the cylinder walls, for whatever reason?
I'd take it apart from the bottom end. You'll find why doing it that way. Its more tedious but won't hurt anything.
The pistons were just froze in place. I put acetone / tranny fluid in the cylinders and tapped the top of each one. Numbers 1 and 4 stuck but I got them moving and all cleaned up. Thanks though. I appreciate all the help from the people here.
 
Solution

1990TSIAWDTALON

Moderator
9,128
4,963
Nov 14, 2013
Independence, Kansas
Gotcha, best of luck on the other 2
I think your doing the best you can without just busting them out as I've had to do on other motors. Keep up the acetone/atf.
Work those other 2 alternately and they should start to move. Crossin my fingers for you. I have a 4g block froze from aluminum slag on its cylinder wall and that bi*** wont budge. I'm about to try sulfuric acid in that bore as a last resort before I use an air chisle and break it out of bore, which I DON'T want to do.
 

waltah

Proven Member
305
128
Mar 2, 2011
fairfield, Virginia
Gotcha, best of luck on the other 2
The bottom end was still together so getting 1-4 (the stuck two) moving also moved the others.

This was a very clean story: Car was running, a head gasket failure (prob'ly a water leak with that ...) then sat idle for a year and now it's frozen. Journals, some massive failure in the bottom end are really unlikely with that story but traces of rust in the cylinders making too big a load for a breaker bar with the journals at 3 o'clock -- 9 o'clock (worst position for mechanical advantage), yes that's a real good bet.

So just a bit more force applied directly to the stuck parts -- the pistons -- made sense.

In a messier situation -- collision with engine frozen, got the car from wrecking yard with ??? story, etc. -- going in from the bottom would have been smart.

There's a lesson here though: If an engine is disabled and work won't start right away it's probably smart to turn it to TDC if it is safe to rotate. (That is, if the valve timing is known to be okay.) That makes it as easy as possible to turn over when ready to start work -- that is, maximum force on the pistons per force on the crank. Also probably good to put some oil in the cylinders and turn it over once.

Of course when I had a Mitsu engine waiting for me to get around to replacing a blown head gasket I did none of that ...
I have a 4g block froze from aluminum slag on its cylinder wall and that bi*** wont budge. I'm about to try sulfuric acid in that bore as a last resort before I use an air chisle and break it out of bore, which I DON'T want to do.
Ho Lee Shirt! The acid certainly ought to work but how much of a rebore might be needed to salvage the block, who knows. But -- I'm guessing you've done this before and know how so I'll just sit here in awe of methods even more determined than mine!

Good luck with that!
 

1990TSIAWDTALON

Moderator
9,128
4,963
Nov 14, 2013
Independence, Kansas
I'm hoping it all works out for BOTH OF US ROFL
 
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