Cylinders 1 and 3 not firing

grandmaster

New Member
Nov 18, 2005
11
0
0
Edmonton
I completed an install of a MHG, 550's/lex/walbro and plugs. When I started up, it ran really rough, and I found that cylinders 1 and 3 were not firing. The plugs fire and injectors were tested by RC before shipped. I tore apart the engine again to find what's going on. Here are some things that were sugested to me by a mechanic, that I'm looking at.

Would an incorrectly installed HG cause just 2 to not fire?
Could I have installed the cams on the wrong sides? Is it possible? Are they labelled?
 

Nick M

Black Rifles Matter
Sep 9, 2005
8,894
38
48
U.S.
www.ebay.com
No and no. Since 1 and 3 are not companion, it is not likely. I think a plug gap is closed, wrie not on good, injector plug loose, etc.

You can't put the cams in wrong. The sprocket wont go on, and switched wont work either becuase of the CPS/distributor.
 

Marcenator

Marc T.
Apr 29, 2005
22
0
0
59
Edmonton, Alberta Canada
grandmaster said:
I completed an install of a MHG, 550's/lex/walbro and plugs. When I started up, it ran really rough, and I found that cylinders 1 and 3 were not firing. The plugs fire and injectors were tested by RC before shipped. I tore apart the engine again to find what's going on. Here are some things that were sugested to me by a mechanic, that I'm looking at.

Would an incorrectly installed HG cause just 2 to not fire?
Could I have installed the cams on the wrong sides? Is it possible? Are they labelled?


That really sucks Simon that the mechanic didnt figure it out. I guess we will just have to take another stab at it. Time to start from scratch and swap some parts out. Maybe put back old injectors, change the spark plugs. I'm sure with a little time we can figure it out. Give me a shout and we can arrange some time.

Marc
 

jdub

Official SM Expert: Motor Oil, Lubricants & Fil
SM Expert
Feb 10, 2006
10,730
1
38
Valley of the Sun
Nick's right...simple things 1st. Check the sequence on the coil packs: Pass side 1 & 6, center pack 3 & 4, Drv side 2 & 5. Swap the plugs out from a good cylinder. Test the spark plug wires & coil packs. Make sure the packs have a good ground.

If you're using RC 550's, you had to splice the clips to the harness...check the splice for a good connection.

Good luck!
 

grandmaster

New Member
Nov 18, 2005
11
0
0
Edmonton
Marcenator said:
That really sucks Simon that the mechanic didnt figure it out. I guess we will just have to take another stab at it. Time to start from scratch and swap some parts out. Maybe put back old injectors, change the spark plugs. I'm sure with a little time we can figure it out. Give me a shout and we can arrange some time.

Marc

It was quite a waste of money. I pulled the problem injectors out, cut thier connections and re-soldered them, just to ensure the connection is correct. I also got new plugs. I'll put it all together again tonight and see if that fixes it.