07-28-2013, 01:12 PM | #1 |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
help
So the wife and I took a drive today in the A and had some trouble. Everything was fine and we had drove several miles. Came to a stop sign and when we took off again we lost power. I looked at ignition switch and the key was turned back just enough to kill it I guess. It has happened before. So I turned they key back on and was fine for a few seconds then BANG backfire! Then crazy engine knock and no power so I killed it and brought it to a stop. Looked all over the engine and didn't see anything out of norm. Let it sit for a few minutes and tried to start it again. It started and knocked for a few and then stopped knocking but have less power and not much oil pressure. I limped it home and now deciding where to start.
|
07-28-2013, 02:11 PM | #2 |
Senior Member
Join Date: Dec 2012
Location: coquitlam b.c. canada
Posts: 130
|
Re: help
I think you should take a look at dist and timing after that I,d look at timing gear possable oil pump and dist. Drive gear. Good luck
|
Sponsored Links (Register now to hide all advertisements) |
|
07-28-2013, 02:53 PM | #3 |
Senior Member
Join Date: Feb 2011
Location: Lincoln, Nebraska
Posts: 1,912
|
Re: help
Probably when the switch turned off you built up unburnt fuel in the muffler causing the back fire. May be possible that you collasped a baffle or two in the muffler and it's causing back pressure and loss of power. Going to be loud but pull the muffler loose from the manifold and see if you gain back your power.
A's don't have very much oil pressure to start with. Mostly they flow a lot of oil with very little pressure. As long as your registering a couple lbs. or so your probably good.
__________________
Dave / Lincoln Nebraska Last edited by 1crosscut; 07-28-2013 at 02:55 PM. Reason: Added information |
07-28-2013, 04:10 PM | #4 |
Senior Member
Join Date: May 2010
Location: Alabama
Posts: 8,099
|
Re: help
I would remove the side timing cover, turn the engine over with the starter , with the spark plugs removed. Watch the teeth on the timing gear when it turns. I figure that some teeth will be damaged and missing.. There are two 5/8 bolts on the side and one under the edge of the oil pan, that a 1/2 inch socket will fit. If you are careful the side timing cover can be removed without damage to the oil pan gasket. When the timing gear starts to fail, it will buck and knock and won't run good at all. The cam turns the oil pump, if the cam gear is striping and skiping the oil pump can't function at an optimum level.
|
07-28-2013, 04:32 PM | #5 |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
Ok ill check all of that also. My coil doesn't have much power now either when I use the tester.
|
07-28-2013, 06:48 PM | #6 |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
Sponsored Links (Register now to hide all advertisements)
|
07-28-2013, 06:53 PM | #7 |
Senior Member
Join Date: May 2010
Location: Mpls, MN
Posts: 27,582
|
Re: help
With timing pin in the cam gear dimple, is the rotor pointing at #1 and just ready to open the points? CCW rotation
|
07-28-2013, 07:16 PM | #8 |
Senior Member
Join Date: May 2010
Location: Camino, CA.
Posts: 3,086
|
Re: help
Start by telling your wife that you're sorry, your Model A is sorry and she doesn't have to go on the next ride, unless she wants to. You'll find out how much she loves you. My wife and I have been riding in our Model As since the late 60s. She always takes a good book and now her favorite Model A tool, her cell phone.
|
07-28-2013, 07:44 PM | #9 |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
Yes its at #1 but I think the points may be a little bit before just opening
|
07-28-2013, 07:46 PM | #10 | |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
Quote:
|
|
07-28-2013, 08:38 PM | #11 |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
I'm wondering if it dropped a valve.
|
07-28-2013, 09:34 PM | #12 |
Senior Member
Join Date: May 2010
Location: Mpls, MN
Posts: 27,582
|
Re: help
Crank the engine so the bad cylinder piston is TDC on firing, then blow compressed air into the spark plug hole. If it has 0 compression, the air will come out the carb (intake valve), or tail pipe (exhaust valve), or oil fill pipe (bad rings or piston).
|
07-29-2013, 09:14 AM | #13 |
Senior Member
Join Date: Jul 2010
Location: Pennsylvania
Posts: 1,106
|
Re: help
So your problems all started from a backfire due to a bad ignition switch? Whenever someone in our club has problems with their ignintion switch, the first thing we look at is how many keys do they have hanging on their keychain. All that extra weight pulling on those repop switches, which usually do not have a strong detente on either the on or off positions, is the first culprit that we find causing the intermittant switch problems.
|
07-29-2013, 10:18 AM | #14 |
Senior Member
|
Re: help
Double check the ign switch for reliable operation. An intermittent switch will show all the symptoms you describe.
__________________
What's right about America is that although we have a mess of problems, we have great capacity - intellect and resources - to do some thing about them. - Henry Ford II |
07-29-2013, 03:33 PM | #15 |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
Piston is moving couldn't get a good look at valves. Piston looks wet and looks like it has some scaring on the head of piston.
|
07-29-2013, 03:36 PM | #16 | |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
Quote:
|
|
07-29-2013, 03:38 PM | #17 |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
But I have hardly any oil pressure and it was knocking to beat the band for a minute. Ignition switch wouldn't cause that and no compression in #3 cylinder.
|
07-29-2013, 03:56 PM | #18 |
Senior Member
Join Date: May 2010
Location: Alabama
Posts: 8,099
|
Re: help
You may have a combination of problems. I had a lot of problems with the low cost ignition switches. The only reason that I didn't mention the switch in post number 4 was because you mention knocks and loss of oil pressure in the original post. You've got a strange combination of symptoms!!
Last edited by Purdy Swoft; 07-29-2013 at 04:41 PM. |
07-29-2013, 04:07 PM | #19 |
Senior Member
|
Re: help
Please describe your engine, Stock or what? Stock engine only has two or three pounds when warmed up.
__________________
What's right about America is that although we have a mess of problems, we have great capacity - intellect and resources - to do some thing about them. - Henry Ford II |
07-29-2013, 05:17 PM | #20 |
Member
Join Date: Apr 2013
Location: Indiana
Posts: 79
|
Re: help
Its just a stock engine with stock head.
|
|
|
Sponsored Links (Register now to hide all advertisements) |
|