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1st cylinder not firing, how do I tell if it's a crack or piston rings?
#1
Posted 15 January 2004 - 01:16 AM
I put some oil in the cylinder to test it out, all it did was puff smoke out the back. Taking the spark wire off the plug results in no change of idling sound at all. Is there a crack in the intake and exhaust ports?
Is the only way to find out to take the head off?
#2
Posted 15 January 2004 - 01:22 AM
Sorry just wishful thinking maybe I didn't read something completely.
#3
Posted 15 January 2004 - 01:24 AM
As to rings "just going", that's apparently what happened to my engine. It was running in tip-top shape then all of a sudden it wasn't making any power. I tested compression and three of the cylinders were perfect, while the other had half their compression. The rings were the culprit. I have no idea what made them go, but I'll tear that engine apart after I get the rebuilt one in.
#4
Posted 15 January 2004 - 01:24 AM
Used a new spark plug as well. As well as an old but good one.
#5
Posted 15 January 2004 - 01:25 AM
- you got a good hookup for rebuilt engineS?
#6
Posted 15 January 2004 - 01:28 AM
#7
Posted 15 January 2004 - 01:30 AM
#8
Posted 15 January 2004 - 01:35 AM
#9
Posted 15 January 2004 - 01:43 AM
#10
Posted 15 January 2004 - 02:16 AM
so maybe it's not grounded properly to the head? this sounds like an all too EASY and certainly interesting idea as a fix. This is probably it.
#11
Posted 15 January 2004 - 04:32 AM
Hm. Oh well, the car is at my girlfriend's house, so I have to wait to touch it until tomorrow.
#12
Posted 15 January 2004 - 05:29 AM
Could be enough of it to cause plug not to fire, as carbon will flow the electrical charge easier than the charge can jump the gap of the plug.
As for you getting a charge when playing with the wires.
As mentioned above, pull the plug, re-attach the plug wire, lay it on the block assuring a good grounding of the plug, then have an assistant crank engine while you watch for spark at plug.
No spark would lead me to think of bad wires, and/or disty cap.
If you get a spark at the plug, I would then pull a compression test on the engine.
Also, if you have the means to do it. I would use the tester fitting to apply an air source to the cylinder. Helps to have the piston at Top Dead Center when doing this test. (use pencil in plug hole to verify TDC).
Listen for air at the intake opening, exhaust pipe, oil fill tube, and look for bubbles in the radiator.
Results of this test are;
At intake--bad, or stuck intake valve/seat.
At exhaust pipe--bad, or stuck exhaust valve/seat.
At oil fill tube--bad piston rings.
Bubbles in radiator-- bad head gasket/cracked head.
Just my .02
#13
Posted 15 January 2004 - 05:40 AM
I do have a compression tester on loan from Hondasucks. Just need someone else's help with it.
The rest of the info is surely good to know.
#14
Posted 15 January 2004 - 12:38 PM
one head that was questionable that i used, took a dump later, i suspect a dropped valve seat also
a compression test will verify this.
#15
Posted 15 January 2004 - 12:50 PM
GD
#16
Posted 15 January 2004 - 01:21 PM
#17
Posted 16 January 2004 - 01:29 PM
#18
Posted 16 January 2004 - 02:36 PM
3 plugs were burning normally.. the 4th on #1 was black and oil covered.. very fouled..
so i changed all the plugs, and she runs like new.. but you already got new plugs.. i'm still wondering why mine was gooey with oil.. am thinkin she might have a valve issue as well, but she doesn't smoke, miss, nothing.. i did have to add half a quart of oil since i got her (1500 miles ago) but shes got 199,500 somthing on her and looks original.. going to take a pic when she his 200k even..
let us know what ya find out.. would be interesting to know.. how'd your old plugs look when they came out?
#19
Posted 16 January 2004 - 03:03 PM
one was probably black from the 'oil in the cylinder' idea.
will check valves later today.
#20
Posted 16 January 2004 - 03:17 PM
and give that a shot... maybe even try the new plug from #2 in #1.. might have a bad plug even though its new..
in any case, your problems might be what i'm looking at in the future if its the same thing.. which it sounds like it is..
i'm thinkin about doin an ea82T transplant into mine this summer tho
#21
Posted 16 January 2004 - 04:41 PM
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