General Tech Help Good at troubleshooting? Have a non specific issue? Discuss general tech topics here.

Dead Engine?

Old Jan 18, 2009 | 09:20 PM
  #11  
finch13's Avatar
Been Around A Long Time Member
Joined: Jun 2007
Posts: 7,381
From: St. Paul, MN
Default RE: Dead Engine?

You may have bent valves...

If you had a tension problem with the old belt, the first thing I would have replaced wouldve been the tensioners.

With the cam gear facing UP and the notches on the gear lined up with the cylinder head, the crank pulley should have the middle (TDC) of the 3 lines (red) lined up with the crosshair on the lower TB cover. The white mark is for 15* BTDC and this would be the correct idle timing when using a timing light clipped to the cyl. 1 spark wire.
 
Old Jan 18, 2009 | 09:29 PM
  #12  
TexasHonda's Avatar
Super Moderator : And A Texan
Joined: Feb 2007
Posts: 9,652
From: Katy, TX
Default RE: Dead Engine?

If the timing between crankshaft and valve train was off too far, valves may have hit pistons and are bent and not able to seat. This causes loss of compression and failure to start. To confirm, you might ask a shop to perform a borescope inspection through the spark plug holes. They will be able to confirm bent valves and whether any piston damage has been done. If piston damage, the engine is probably not worth repairing, and purchase of a used engine will be more cost effective.

I had this happen on a Acura 2.5TL due to some faulty work done by a mechanic replacing the harmonic balancer. He was working for my son. Result was 5 bent valves, requiring head removal, rebuild, and installation. Fortunately no piston damage occurred, but the borescope was helpful to avoid possibility of pulling the head to find damaged pistons.

The camshaft sprocket has TDC timing marks near the sprocket teeth on inside and outside of sprocket. These mark should align horizontally w/ top of timing cover behind sprocket. There is also a mark on the sprocket that aligns w/ a boss on the head vertically, however Honda does not mention using this mark.

good luck
 
Old Jan 19, 2009 | 04:30 PM
  #13  
Clydesdale
Unregistered
Posts: n/a
Default RE: Dead Engine?

I've been helping 91wagon fixing this car and what I need to know is where does the crankshaft pully lign up to? Is there a make that ligns up to a position? The camshaft pulling... I understand where that one goes to; no problem there.

Thanks
 
Old Jan 19, 2009 | 04:34 PM
  #14  
finch13's Avatar
Been Around A Long Time Member
Joined: Jun 2007
Posts: 7,381
From: St. Paul, MN
Default RE: Dead Engine?

I believe there are lines on the the CSP that correspond to marks on the block, one at 90* and one at 180*.
 
Old Jan 19, 2009 | 04:52 PM
  #15  
JimBlake's Avatar
Super Moderator
Joined: May 2006
Posts: 18,398
From: Wisconsin
Default RE: Dead Engine?

CSP??
I thought back in 91 the marks were on the flywheel; visible thru a view-hole near the front corner of the head. Kinda like 1:00 oclock position if you were viewing from the right-front wheel.
 
Old Jan 19, 2009 | 05:26 PM
  #16  
PAhonda's Avatar
Super Moderator
Joined: Sep 2006
Posts: 16,329
From: Houston, TX
Default RE: Dead Engine?

There is a mark on the engine block for the crankshaft on my 95. Also, there is a line on the flywheel that you can line up. See the first pic in the link below.

https://www.hondaaccordforum.com/m_22119/mpage_2/tm.htm
 
Old Jan 19, 2009 | 06:53 PM
  #17  
TexasHonda's Avatar
Super Moderator : And A Texan
Joined: Feb 2007
Posts: 9,652
From: Katy, TX
Default RE: Dead Engine?

The Crank Shaft Pulley has marks on the timing belt sprocet (dimple) that align w/ a mark on the engine behind the sprocket near the top position. There should also be access to the flywheel through a rubber grommet on the flywheel cover (near the upper radiator hose). My comments assume that the 91 Accord is same as 90 Accord, for which I have a manual.

good luck
 
Old Jan 19, 2009 | 10:07 PM
  #18  
Clydesdale
Unregistered
Posts: n/a
Default RE: Dead Engine?

Ok, I did the timing as per all the instructions I could find on the net and I'm positive I did it correct.

Did a compression test; nothing ... ZERO! While rotating the crankshaft (cam etc..) manually with a socket/ratchet, I noticed that when the rocker arms (say piston # 1) didn't have pressure on the intake & exhaust valves that there is at least about 1/16" gap between the top of the valve stem & rocker arm (where they make contact); 16 valves are like that.

I turn it slowly ccw at the crankshaft and piston 1 goes down and both intake & exhaust valves are closed (with that gap / loose rocker).... piston comes back up all the way with all 4 valves still closed ..... so there should be compression for sure but there isn't any .... so all the valves must be bent in my opinion???? The second rotation, the valves open so you can't really tell during that rotation.

Correct? It's pootched?
 
Old Jan 20, 2009 | 06:41 AM
  #19  
JimBlake's Avatar
Super Moderator
Joined: May 2006
Posts: 18,398
From: Wisconsin
Default RE: Dead Engine?

Sounds like bent valves.
 
Old Jan 20, 2009 | 07:16 PM
  #20  
TexasHonda's Avatar
Super Moderator : And A Texan
Joined: Feb 2007
Posts: 9,652
From: Katy, TX
Default RE: Dead Engine?

I agree, you have a bent valve in all 4 cylinders. You can either remove head to inspect pistons or have borescope inspection performed to check for holed pistons. Most times pistons survive, but not always.

good luck
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
matttv
General Tech Help
14
Aug 12, 2013 03:50 PM
Lenno
General Tech Help
0
Jan 29, 2012 07:45 PM
ohill1981
General Tech Help
7
Jun 16, 2011 11:48 PM
ACCORDingly
Audio/Visual Electronics
3
Mar 22, 2005 02:19 AM
2pwrful
General Tech Help
1
Mar 14, 2005 04:22 PM


Thread Tools
Search this Thread

All times are GMT -5. The time now is 12:47 AM.