Ideas on Mercruiser 260, 1980 - Good idle under load, high in neutral, and shift prob

[CanyonDoug]

Just a quick thanks to everyone for continuing to assist with ideas and input. I truly appreciate it and will keep advised since you have all taken the time to show an interest in helping.
- Doug

[Capt.Insane-o]

http://m.ebay.com/itm/262820586364?_...75&_mwBanner=1

[flabum1017]

http://m.ebay.com/itm/262820586364?_...75&_mwBanner=1

[CanyonDoug]

OK... Update is that removing throttle cable showed no difference in results. Looking at some buggered screws on the carb tell me someone with little patience/knowledge/tools had it apart at some point... And my guess is they may have done more harm than good and likely did not accomplish a proper cleaning and replacement parts were likely substandard. So, bit the bullet and sent it off to Cliff Ruggles.... On marine carbs his turn around is immediate.... Autos are 5 month back log! Once I get it back, I'll post the results. Cliff bets the idle jets are varnished solid... Eager to get it back from an expert rebuild. Disty looks to be a good move as well if all else fails. I appreciate the link; I know what to look for now.

[powerabout]

Checked the timing yet?

[CanyonDoug]

Checked the timing yet?

That's next when I get the carb back. Sent it out first since it is likely and really no other way to tell if idle circuit is gummed up... Sure acts like it since I have to dial in so much throttle. And I'll have more peace of mind knowing that the carb is factory fresh and even better with newer, ethanol resistant materials. Timing is also something I want to be sure of. Will get a light or have a buddy with one check and help set it. For me to do it, I'll have to watch a youtube video. Saw one before and checking didn't seem too challenging, but I'm not sure on setting it. Think I have to loosen and gently rotate the disty, right? Laughable, I know... Not sure how I got this far and don't know how!

[flabum1017]

timing is easy. let it run at idle. put the pickup of the light on #1 spark plug wire and aim at the timing tab. Tun the distributor until the mark on the dampner aligns with the 8* BTC mark on the timing tab. Make sure it is idling below 800. The readjust the carb. Once that is set, If you use a timing light with a dial on it, Run the engine at 3000 rpm and check the timing by turning the dial until the mark on the dampner lines yp with the zero mark on the timing tab and see what the dial says. Should be around 26 degrees, if too low or too high, time for a new distributor.

[powerabout]

What i am getting at is the distributor has rusted weights/cams and hence it advances at low rpm so when you put it in gear it retards and when you hit neutral it advances.

[CanyonDoug]

What i am getting at is the distributor has rusted weights/cams and hence it advances at low rpm so when you put it in gear it retards and when you hit neutral it advances.

Makes sense. I'll have to probably pull it to inspect the springs/weights, but that makes sense. But would that not also throw off the high end? Top end is fine, runs up to 4400, 4500 and runs well.

[Dave Strong]

Makes sense. I'll have to probably pull it to inspect the springs/weights, but that makes sense. But would that not also throw off the high end? Top end is fine, runs up to 4400, 4500 and runs well.

Just do one thing at a time, try the carb first if it doesn't fix it look elsewhere. If you have never taken a distributor apart don't do it. The gear goes on only one way to be correct even though it can go on 2 ways. Just saying if your in over your head get experienced help.

Dave

[powerabout]

Top end probably not effected.
Dont pull the dist out until after you check it.
Looking at the parts wont tell you anything.

[CanyonDoug]

Just do one thing at a time, try the carb first if it doesn't fix it look elsewhere. If you have never taken a distributor apart don't do it. The gear goes on only one way to be correct even though it can go on 2 ways. Just saying if your in over your head get experienced help.

Dave

Yeah, it's a bit beyond my pay grade, I'll def get help if I need to go in that direction.

[flabum1017]

As for the distributor, just set the timing and run the engine up a few times while watching the mark with the timing light on it. Make sure it advances and returns to 8* at idle. If it's getting to 26* at 3000 and 8* at idle, you're good to go. If not, get that distributor kit that was posted.

[Dave Strong]

A 80 260 should be set to 8deg BTDC at 650 - 700 rpm in gear. Or as Merc says at idle speed witch is in gear. If you set it Rev it in neutral put it back in gear with close to the same idle speed the advance system could be hanging up.
Plugged up idle passages sort of make some sense, we will see after the carb is rebuilt. Just set everything in gear.

Dave

[CanyonDoug]

Hope it is on its way back tomorrow.... UPS ground is their choice of ground delivery. Prob see it Monday or Tuesday. Will post findings once I get it back in place. Sure appreciate everyone's time and help on this. Will be checking timing as described.