motor ??
Thread Starter
Instructor
Joined: Dec 2004
Posts: 130
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From: Carlisle Pa.
motor ??
72 auto ps pb
Number 2 and number 8 cyl. arent firing, have spark to plugs.
New dist.,wires, plugs. compression in all cyl. between 140 150 tested hot. no visiable oil in water or water in oil. but do have oil on #2 plug HELP
Number 2 and number 8 cyl. arent firing, have spark to plugs.
New dist.,wires, plugs. compression in all cyl. between 140 150 tested hot. no visiable oil in water or water in oil. but do have oil on #2 plug HELP
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Okay, I am aware of the methods but I was wondering which way you chose to test.
Also, how do you know you are not getting combustion in those cylinders? How did you determine that they are not operating?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Le Mans Master
Joined: Jan 2006
Posts: 6,504
Likes: 139
From: Butler Pa
This is the most likely cause.
A less likely cause could be bad plugs. I've seen plugs that would fire when out of the engine but not in the engine when under compression. Switch them with ones that are firing and see what happens.
A less likely cause could be bad plugs. I've seen plugs that would fire when out of the engine but not in the engine when under compression. Switch them with ones that are firing and see what happens.
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Instructor
Joined: Jul 2007
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From: Sheboygan Wisconsin
not firing
Did this start after you put the new distributor in??
Might be a couple teeth off.
Does it start hard? Turn over lumpy?
If before, maybe a valve spring. Might even be the spring on the opposite side. You also mention oil on #2.
Might be a couple teeth off.
Does it start hard? Turn over lumpy?
If before, maybe a valve spring. Might even be the spring on the opposite side. You also mention oil on #2.
Thread Starter
Instructor
Joined: Dec 2004
Posts: 130
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From: Carlisle Pa.
all plugs but 2 and 8 looked good 2 was clogged when taken out at first and 8 was just oil fouled
cleand them put them back in and 2 gets oil fouled 8 stays clean
how i tested to see if they were firing was pull wire no difference in the way motor was running
Thread Starter
Instructor
Joined: Dec 2004
Posts: 130
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From: Carlisle Pa.
Thread Starter
Instructor
Joined: Dec 2004
Posts: 130
Likes: 0
From: Carlisle Pa.
Thread Starter
Instructor
Joined: Dec 2004
Posts: 130
Likes: 0
From: Carlisle Pa.
I tdc #1 cyl. dropped in dist. then wired #1 to the rotor.
at tdc the mark on the balancer lined up so i don't think it jumped timing
Advanced
Joined: Sep 2006
Posts: 78
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From: Nashville NC
Steeler, From what I hear ya saying it sounds like you may have an issue with the valves. Pull you valve cover off that side & check to see the valves are opening & closing on those two cylinders. Since the two cylinders are located on the same side but not next to each other & you say the wires are firing it has to be something valve train related. The plugs being fouled are caused by the cylinder not clearing . Also check to see if the header pipe or exhaust manifold at those cylinders is getting hot. No heat, no fire. I would also suggest starting over with fresh plugs on those cylinders because once a plug has fouled it may short up in the insulator and will not fire even after cleaning. I have seen that a dozen times. My Harley is notorious for that. Hope this helps. Good luck.