light shining throuh reed pedals

[tvpear12]

I am looking through my intake and i can see a small amount of light shining through the reed pedals. is this ok for a small amount of light to be seen? or is it in need of a new set of reed pedals? my engine is a 90 horse evinrude v-4. as you may have read in my other post i lost a ring and ringland on my engine and i am rebuilding it now. wanting to address every thing i know of that might have caused this. not sure if it was just to much clearance and the ring jumped over the ring positioning pin or just what happend.i was just running across the lake when i droped the upper starboard side cyl. took it home and found the plug gap had cosed up. ring inbedded in the top and lower cyl. i am sure the rings are what closed the gap the imbeded into the top of the pistons. if you think it was another cause please fill free to let me know as i am kinda a dumass when it comes to diagnosis. thanks for any help.

 

[WillyBWright]

Re: light shining throuh reed pedals

If the gap between the reeds and reed blocks are just a few thousandths, don't worry. They'll be slammed shut just fine with the motor operating. If that motor is old or has a lot of hours on it, you might want to replace them. But don't do like a lot of people do...turn them around. That's when they like to break off.<br /><br />I'd probably go thru the carbs. If that bad cylinder was running lean, then it'll fail again if you don't clean out the restriction.

 

[Dhadley]

Re: light shining throuh reed pedals

Yep, a small bit of light is probably OK. If you can put pressure on it with a sheet of writing paper and it closes then its good. <br /><br />Since you are right there anyway, now is an excellent time to consider Boyesen reeds. I highly recommend them.<br /><br />As far as the cause of the ring breaking, most likely it was from coking. Especially if the motor was set up in the low to mid 5000 range and decarb was not done regularily. <br /><br />Coking usually shows up first on the starboard side of a crossflow. Nothing unusual. Most of the time we find the broken ring resulted from the coking which is related to set up and (lack of) maintenance.

 

[tvpear12]

Re: light shining throuh reed pedals

I am not aware of what coking is please explain. and yes my rpm is right at 5000 and my prop says 13x19 what should i do to set it up right? my 90 horse is mounted to a 1989 tracker 1600tf tournament fiberglass. also repair manual says 28 degrees on the timing. i was told by a local shop to set timing back to 26 degrees and go 1 larger on the main jet what do you guys think?

 

[Dhadley]

Re: light shining throuh reed pedals

Coking is that black sticky carbon like substance you see on the pistons. It causes the rings to stick in the goove on the side oppsite the ring end gap. As more and more of the ring gets stuck in the groove the piston loses support at the top and starts to rock back and forth. Eventually the piston rocks enough that the ring ends shear off. <br /><br />If you hold the piston up and look at the locating pin usually the most damage is done on the right side of that pin. Wierd.<br /><br />5000 rpm is lugging that motor. Lugging causes excess combustion temp / heat. Excess combustion temps promote coking. <br /><br />You can do a couple of things once you get the motor rebuilt. <br /><br />If you dont change the set up, decarb more often. The manufacturer calls for decarb every 50 hours. In your case I would cut that in half -- every 25 hours.<br /><br />If you work with the set up and get to, lets say 5500, decarb as the manufacturer suggests.<br /><br />If you can get to the optimum set up, 5800-6000 with an average load, you may not need to decarb at all. I would still do it as an annual maintenance deal whenever you change the lower unit oil.<br /><br />As for the timing and jetting, I'd go with 26 degrees for break-in and then try 28. If there is no improvement -- go back to 26. The jetting should be very close to OK. The idle circuit may be a tad lean with todays fuel but the high speed should be OK. <br /><br />Work with the set up. Thats the key.

 

[tvpear12]

Re: light shining throuh reed pedals

well with the prop i stated that i had what can i do to get those rpms up to the 5500 to 6000 that you talked about?what do i change to set it up as you spoke of?

 

[Dhadley]

Re: light shining throuh reed pedals

We would start by looking at your present set up starting with making sure the motor has a clean bill of health. Since its going to be fresh we wont worry about that. Then we would look at motor height (X dimension) and your prop style and how that reacts with your particular hull design. We also look at balance.<br /><br />Hopefully we could raise the motor on the transom. If its mounted all the way down now you may be able to raise it depending on how good your prop is. Raising the motor reduces drag. Reducing drag improves efficiency. You may gain as mauch as 150-200 rpm per hole. <br /><br />A lot of times as we increase the rpm the boat gets up higher when on plane and further reduces drag. <br /><br />Worst case scenario -- the prop ventilates and we move it back down or go to a better prop.<br /><br />As things improve sometimes we move on to jackplates, tabs, fins etc. A lot depends on defined use. But we start with adjustments, then spend money.

 

[tvpear12]

Re: light shining throuh reed pedals

ok, Lets start with the boat. This boat the 1600tf tournamant has a inset bottom where the drain plug is. the engine is all the way down on the transom but it seems as if the water is pushing away before the prop, because of the inset bottom. I also noticed that when trimmed all the way out it acts as if the prop is out of the water to much. I dont think the trim is the problem as much as maybe the way the bottom of the boat is just before the prop.Almost like the engine should have a longer shaft. i hope you understand what i am trying to say here.kinda like the prop is slipping but its not cause when the trim is down it does not sound that way.Also when i checked the rpm i am almost sure i had these 2 bad cyls. as i just bought the boat and only had it out 3 times before the engine went down on the 2 cyls. maybe when its fresh it will have more rpms just a thought.