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Wet Dream
06-11-2002, 11:13 AM
Every so often it would backfire at high revs, never in a controlled or repeating manor, but occassionally, from the exhaust. I don;t know if I should look for cracked plug wires, or my distributor cap. The reason I question the dist cap is due to the fact that it was pouring rain (6 hours straight) while towing down to Anna. I did have water in the oil, but found its way into the block via the breather. I'm thinking that water or condensation is the culprit in the cap and when run hot, it would foul a spark once in a while. Anyone else wanna give their $.02 worth?? Thanks in advance. It never did this before, just toward the end of the last day.

78Eliminator
06-11-2002, 11:29 AM
Could be:
a. a lean condition
b. water in the fuel (or cyliners)
c. timing off
My suggestion is to do a full tune up. Replace sparks, wires, cap, rotor, fuel filter, air filter (if you have one).
Also, you might want to get out on the lake (or river) and hammer your boat and once you've been at full throttle for about 30 seconds, cut the engine and pull a plug out and see what's up. Just don't drop it in the water : )
78Elim (Justin)

beached1
06-11-2002, 11:53 AM
Have you changed or rejetted your carb recently? It sounds like you may be running lean.

Wet Dream
06-11-2002, 12:11 PM
Its definately running rich, I kinda like it that way. Water in the fuel, possible, but the glass filter shows it clean, timing maybe, but this is an intermittent problem.

78Eliminator
06-11-2002, 12:26 PM
Well, how do you know it's rich? Do a plug reading. Do it for your country.
78Elim
Stars and Stripes

Torino Jet
06-11-2002, 12:43 PM
My Olds 455 did this for a long time. I thought it was a jetting issue, and just assumed that i wasn't a master carb tuner. It turned out to be the timing advance. I have a mallory unilite w/ meachanical advance, and it wasn't advancing enough. Fixed that problem , and it hasn't popped since.

Cheyenne19
06-11-2002, 12:47 PM
What kind of dist. do you run? I would be suspicious of the rain and your dist.

Wet Dream
06-11-2002, 01:24 PM
The plugs look great, good burn, little rich, still healthy, the distributor is an HEI jobber with vac adv. Everything was working great until late Sunday. I was going to run it this afternoon, but I have too many things going on right now.

78Eliminator
06-11-2002, 02:33 PM
If you have so much going on, how are you able to post sucka?
jk

Wet Dream
06-11-2002, 07:53 PM
Most of whats keeping me busy is posting pics of the Anna trip. I have over 140 pics. The rest is trying to tackle the yardwork that was neglected while I was gone. There's always next weekend for that, right?? But boating will probably be on the agenda. http://free.***boat.net/ubb/smile.gif

Eric455
06-12-2002, 12:13 AM
its not a carb issue, timing is what your problem is. do a full tune up, that should fix it. good luck.

kojac
06-12-2002, 11:46 AM
Wet dream,
If you were running good before Anna and as hot and humid as it was this weekend you probably were not running lean. If you were in pouring rain on the way to anna I suspect water in the gas. Put in a can of dry gas and see if this doen't clear up the problem.
Hot and cold weather will cause condensation in a part full gas tank and cause an intermitant miss. Had this problem several times and dry gas fixes the problem.
If this doesn't work then go to the distributor, plugs, wires,etc.
Good luck and happy ***boating.
Kojac...

Jrocket
06-12-2002, 02:19 PM
Change the cap,rotor and plugs.Check the wires....Let us know

wideopen545
06-12-2002, 06:29 PM
hey bill we just made it home what a week check your dist advance or water in your gas hey give me a call fri night if you can tim

Duane HTP
06-12-2002, 07:28 PM
If all of the above fail to solve the problem, and they should, check for weak or broken valve springs. Duane HTP

78Eliminator
06-13-2002, 07:15 AM
WD, Please let us know when you get it figured out......

Wet Dream
06-14-2002, 06:21 PM
I'll be able to let you know whats going on tomorrow night. I am going to make a run to the local river tomorrow and check it out. I will add the dry gas and also pull the cap, I should be able to see residual water spots inside if that may have been the problem. Thanks guys. Kojac, sorry we couldn't make it out to your side. Hopefully you'll invite us again.

propless
07-06-2002, 06:35 PM
[QUOTE]Originally posted by Wet Dream:
[B]I'll be able to let you know whats going on tomorrow night. I am going to make a run to the local river tomorrow and check it out. I will add the dry gas and also pull the cap, I should be able to see residual water spots inside if that may have been the problem. Thanks guys.
Wet Dream -
Encountered the same thing today, what did you finally find? A fuel issue? Did you need to change out parts, if so what?
Thanks in advance (I posted a problem tonight on "Gear Heads", same issue)!!

Wet Dream
07-07-2002, 01:35 PM
What I found is that I had a bad plug wire causing the backfire. It was causing a late spark and has been great ever since.