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6ballsisall
05-07-2005, 09:01 PM
My memory is flailing me, if your engine is doggy and sputters in the lower power band range but runs like a scalded cat up top do I need to advance or retard the timing?

Also, which way (Clockwise or Counterclockwise) to retard?

This is for my 86 MC with 351 Windsor

milkmania
05-07-2005, 09:05 PM
well....
when the ol' headers on the Nova started glowing cherry red, it seems like they told me to retard the timing a little

nevermind, I got lost and forgot what I was saying:(

Mag_Red
05-07-2005, 10:20 PM
Just twist the distributor and see what it does to the timing. I would say you need to retard it some, but it's been awhile since I wrenched on that sort of ignition system.

erkoehler
05-07-2005, 10:29 PM
Man, where is JimN when you need him! I guess we can give him the weekend off, but Monday morning

:uglyhamme

SKI*MC
05-07-2005, 10:33 PM
Check what going on in your carb, and if you having a timing light, check it out, that always helps dial it in.

6ballsisall
05-07-2005, 10:40 PM
Man, where is JimN when you need him! I guess we can give him the weekend off, but Monday morning

:uglyhamme


No kidding, I need to give him my blackberry and let it buzz him with an email everytime a Jim question comes up!

6ballsisall
05-07-2005, 10:40 PM
[QUOTE=SKI*MC]Check what going on in your carb,

what do you mean by that?

SKI*MC
05-07-2005, 10:45 PM
well when you are going at top speed, does the boat kind of speed up for a split second, then slow down?

6ballsisall
05-07-2005, 10:48 PM
well when you are going at top speed, does the boat kind of speed up for a split second, then slow down?


yes occasionaly it surges what does that mean? btw, i am using a vacuum advance distributor if that makes a difference

SKI*MC
05-07-2005, 10:51 PM
we have a 351 widsow too, and it sounds like we have the same problem, our boat has surges like that too, we think what happnes it, moisture gtes under that distributor cap, and the spark grounds out on little water droplets inside the cap, making the engine miss, and surge at top speed,. Is this what you boat sounds like?

6ballsisall
05-07-2005, 10:55 PM
we have a 351 widsow too, and it sounds like we have the same problem, our boat has surges like that too, we think what happnes it, moisture gtes under that distributor cap, and the spark grounds out on little water droplets inside the cap, making the engine miss, and surge at top speed,. Is this what you boat sounds like?

sort of, mine depending on how the timing is set does it or doesnt. I am having a heck of a time getting the time set. It either runs great down low or great up high, nothing in the middle.

SKI*MC
05-07-2005, 10:58 PM
i see... well i would make a few runs with you motor cover off, and tim it from there, you can just turn around.

k2mc
05-08-2005, 02:01 AM
Seems like it would it be advance it. If the vacuum advance is working properly - its advancing as the rmp's go up and all is good, so retarding it should be worse at all speeds.

as mentioned, the carb could be the culprit too. make sure the choke is moving properly.

6ballsisall
05-08-2005, 10:15 AM
Seems like it would it be advance it. If the vacuum advance is working properly - its advancing as the rmp's go up and all is good, so retarding it should be worse at all speeds.

as mentioned, the carb could be the culprit too. make sure the choke is moving properly.


Thanks, I hope to get to play with it this evening. Just put a new carb on the boat, manual choke that I have disengaged (don't really need a choke for my planned useage.)
I guess I'll pull the cover back and play around with it and see what I get. Better find a thick rubber glove to wear, I got shocked pretty good yesterday with my hand on top of the distributor. :eek3:

milkmania
05-08-2005, 12:57 PM
I got shocked pretty good yesterday with my hand on top of the distributor. :eek3:


dude, you rock!!!!:headbang:

:woohoo:

Leroy
05-08-2005, 01:15 PM
Checklist
1. good spark! :toast:

I got shocked pretty good yesterday with my hand on top of the distributor. :eek3:

JEREMY79
05-08-2005, 04:05 PM
Checklist
1. good spark! :toast:

"note--have spark at distributor"

6ballsisall
05-08-2005, 04:57 PM
In my defense I know not to do that, my hand just bumped it really good when I was adjusting the fuel air mixture :cool:

JEREMY79
05-08-2005, 07:14 PM
been there dude, that sucks. OUCH

Jerseydave
05-08-2005, 08:15 PM
First thing is to check if your accelerator pump is working good on your carb. With the engine off, look down the throat of the carb and move the throttle linkage. You should see a good stream of gas squirt in both barrels of the carb. If not, your engine will stumble on acceleration.
There is an adjustment for that on Holley carbs, if that's what you have. If you don't see ANY gas squirting, you have a bad accel. pump.

2) If you have points in your distributor, make sure you set the dwell FIRST before you set your timing with a timing light. Use a dwell meter, don't rely on a feeler gauge, not accurate enough. ( I assume you have good points, not worn ones.) Worn points will give you problems and bad performance.

3) Set the timing with a light with the vacuum advance disconnected. Reconnect it and take the boat for a test run. If it's still sluggish, advance it 2 degrees at a time, but if it starts to ping, back it off. Don't let your engine ping, it will do damage. Sometimes because of wear on the timing chain, setting your timing to spec may not be enough. But it's a good place to start.

By the way, the engine will start much easier if you hook-up a choke to it.
Sorry so long, hope this helps.

Dave

6ballsisall
05-10-2005, 04:44 PM
Well I talked with Skidim today. They told me my problem was the car distributor. Was told there is a significant difference in the timing curve between the 2. Second, they said none of the boat engine manufacturers ever messed with Vacuum advance so that could be another reason for my problems. So... long story short I guess sometimes you can't be cheap and you have to shell out for the right parts. (the Autolite car distributor was only $24 new :eek: ) Marine Distributor- $285 sigh