OMC Guru's---Dhadley, Walleyehead, anyone....

[tysidor]

Well here is the deal. This has been somewhat covered in another post, but a lot has changed since then. <br /><br />I have a 1977 Evinrude 200hp. Model# 200749<br />The setup is on a 1984 Glastron CVX-20 Sprint. Engine AV plate is even with bottom of transom. Any higher and I lose grip in corners at lower speeds. I have found this to be my best mounting height. <br /><br />I am having a problem with my max rpms. At WOT I can't get above 5000. The interesting part is that I have already experimented with changing props. I bought those cheap hustler interchangeable props off of Iboats. This setup was completely new to me so I decided to start with a 21". I could barely turn 4000-4200 with this prop with only me in the boat. I thought this was way low and figured something was wrong. I ordered a 19" and rpms raised to 5000. Out of desperation I ordered a 17" to see if that brought me upto the range I needed to be. Still maxed out at 5000. So there was no change between the 17 and 19 in rpm. <br /><br />None of this sounds right for a 200hp and a CVX-20 boat. For the life of me I can't figure out way I can't turn more then 5000 rpm.<br /><br />Some tests that I have done.<br /><br />Compression:<br />95, 100, 100, 100, 100, 95<br /><br />Spark Plugs:<br />Used both QL16V and UL77V----Idled significantly better with UL77V<br /><br />Carb:<br />Cleaned low and high speed jets. Nothing looked plugged so I didn't rip the whole carbs apart. (plus I don't know much about carbs)<br />Link and sinc completed.--all open and close together.<br /><br />Timing:<br />With timing light looked like 29. I know it is supposed to be 28, but I didn't really want to screw with it and figued 29 was close. Could this be an issue? Should it be set to anything else with todays fuel?<br /><br />Spark:<br />All cylinders seem to be firing just fine.<br /><br />Altitude:<br />3300ft above sea level<br /><br />Any help or advice would be greatly appreciated. I am getting frustrated and don't know what else to do. Keep in mind that I don't know a lot about boats---give it to me in idiot format.<br /><br />Thanks everyone!!!!

 

[walleyehed]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

What method did you use to set(check) the timing?? Does it still have sea-level main jets???

 

[walleyehed]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

Do we have 3/8" fuel line installed with NO restrictions???<br />Can you verify the throttle plates are completely open @ WOT??? Roll-pin on throt shaft perfectly straight up and down at WOT???<br />How is the nylon roller on the throttle pick-up that rides on the cam???

 

[tysidor]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

The method I used to check the timing was to connect a timing light to the spark plug wire and then rev up the engine to around 5000rpm. It was reading about 29. <br /><br />What exactly are sea level jets? Maybe I just am not familiar with that term, but the only jets I know of were the low and high speed ones. <br /><br />As far as fuel. All my fuel system is brand new. Tank, line, bulb, fill hose, vent hose,connectors, and fuel filter (water filter).<br /><br />Throttle plates are completely open at WOT already checked that. As far as the roll pin I will have to verify.<br /> <br />Tach readings. I connected a Merctronic tach to the plug wire and verifed the readings I am getting with my in dash tach. They were very close to each other. <br /><br />Thanks for the help. I can't tell you how much I appreciate it.

 

[tysidor]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

Thought I might mention. Today I took the boat out with six people and a bunch of gear. It still revs right upto about 5000 and then doesn't go anymore. I would have expected it to drop in rpms with that much load. I really makes me wonder if I am just not pushing enough fuel though.

 

[OBJ]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

Ty....just reving the engine to set the timing will not get you accurate timing. Ideally, the engine should be in the water unrestrained. The timing is set at WOT with a min of 5krpm. But there is another way. Check the post below by Joe Reeves. This method works. You can recheck when you are on the water.<br /><br /><br /> posted June 21, 2004 12:09 PM <br />--------------------------------------------------------------------------------<br />(Timing At Cranking Speed 4°)<br />(J. Reeves)<br />The full spark advance can be adjusted without have the engine running at near full throttle as follows. <br /><br />To set the timing on that engine, have the s/plugs out, and have the throttle at full, set that timer base under the flywheel tight against the rubber stop on the end of the full spark timer advance stop screw (wire it against that stop if necessary). <br /><br />Rig a spark tester and have the gap set to 7/16". Hook up the timing light to the #1 plug wire. Crank the engine over and set the spark advance to 4° less than what the engine calls for. <br /><br />I don't know the full spark advance setting your engine calls for, but to pick a figure, say your engine calls for 28°, set the timing at 24°. The reasoning for the 4° difference is that when the engine is actually running, due to the nature of the solid state ignition componets, the engine gains the extra 4°. <br /><br />If you set the engine to its true setting at cranking speed, when running it will advance beyond its limit by 4° which will set up pre-ignition causing guaranteed piston damage! You don't want that to take place. <br /><br />No need to be concerned about the idle timing as that will take care of itself. The main concern is the full advance setting. <br /><br />Be sure to use your own engines spark advance settings, not the one I picked out of the air here in my notes.<br /><br />--------------------<br />Joe (30+ Years With OMC)<br /> <br />Keep us posted.

 

[walleyehed]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

It takes a hell of a lot more fuel to reach 5K with 6 on board than it does with 1 person....You are limited due to something other than fuel. I have never heard of it, but I wonder if we have a rev-limiting powerpack that has malfunctioned?????<br />77 didn't use a rev limiter, so disregard that one, unless it has been replaced.

 

[tysidor]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

OBJ--- I will try checking and setting the timing that way. As far as double checking it in the water unrestrained at 5000. What do you mean by unrestrained? I am assuming not under pressure? The only thing is at WOT I am barely reaching 5000 so I am assuming the would be considered restrained. I have heard timing on some of the old V6 crossflows should be different then it was back then. Do you know anything about that? On my motor it says 28.<br /><br />Walleyehed--- I guess you are right about fuel. It would take a heck of a lot more to reach 5000 with 6 people versus 1. As far as I know both powerpacks look like the originals. The weird part is that the engine sounds really strong. No odd sounds and never sounds like it is struggling. The only thing is that it doesn't idle great, but most outboards I have dealt with don't idle great.<br /><br />A few other questions. I have noticed that there seems to be a midrange power surge. It seems like with just a tap of the throttle I go from 25 to 35. There is no in between. Any ideas here?<br /><br />This may sound really stupid, but why does the engine rev more freely on muffs versus in the water. I know you aren't supposed to rev up with muffs, but just by moving the fast idle switch it is way more responsive on muffs then in the water. I am assuming it is because it breaths better, but I would assume these engines should breath in the water just the same.<br /><br />Thanks again for the help everyone.

 

[walleyehed]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

It revs on the muffs due to lack of back pressure it would have sitting in the lake.<br />"unrestrained" means not tied up, or on the trailer...On the water moving freely only.<br />My 200 cross-flow is touchy in the same manner as yours...there is a spot where there is no "In between"...on mine, it's around 3500...touch the throttle and bam, it's at 4K. I think that is a result of the full transition of max timing advance and running on the main jets and not the intermiediate circut.<br />On your max advance screw, measure the portion of the screw that is sticking out fwd of the timing tree...it should be somewhere around 3/8"-7/16"...the end with the slot.<br />BTW, I'm still working on the Idle on mine too...I have Boyesen reeds which "Usually" helps smooth out the Idle, but mine is a bit rough too.<br />Do you know if you have cross-over jets or Bleed air jets???<br />At 3300ft, you are going to need to increase the size of the Idle bleed jets, if they are in fact, Idle bleed jets. they would be located directly at the top of the venturi (Inside).

 

[farginicehole]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

Don't mind me, just wanted to subscribe to this thread as I only get 5K with my current setup too.

 

[tysidor]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

A few more things I thought I would mention. I made sure fuel filters (screens)were clean. They are as clean as can be. I haven't had time to mess with the timing, and probably won't for a day or two. The biggest problem is that I store the boat in my buddys garage, so access isn't just walking out the door. <br /><br />Are bad fuel pumps a possibility? How would I check this?<br /><br />As far as Reeds are concerned mine look to be in good shape and are opening and closing correctly. I probably won't spend the money on Boyesen's until I get everything else running right.<br /><br />What should this engine idle at? Just idling and in gear? I am thinking of raising the idle speed just a little to see if that helps smooth out my idle. <br /><br />Is there any possiblity that it is the prop. I wonder if I am getting some exhaust back pressure and it's not allowing me to rev?<br /><br />Thanks again everyone and keep the ideas coming!!

 

[ondarvr]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

I have a 1976 200HP. By going down in pitch (17) and raising the motor I was finally able to get 5,400 to 5,500 on my 19' center console. The motor appears to run fine, but for a 200 it doesn't go very fast or rev very high. I have not been able to find anything wrong with it, so 45MPH at 5,500 is were I gave up. There are other posts with the same issue, if you do a search you will find them. In one recent post Dhadley said people changing from the older 150s to the 200s noticed very little difference in performance, if any.

 

[walleyehed]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

My 200 Rude, '82 model on my 18ft starcraft will turn a 17 6200+....I run about 58MPH with a Turbo II 23P. This cross-flow V6 runs best at 5800 RPM or so, but they "Will" turn alot more if properly set up....<br />Idle speed "should" be about 650.<br />This was a problem for me, and I had to lean My Idle circut down to get a smoother Idle.

 

[farginicehole]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

Walleyehed - I assume that is a "walleye boat"? Like a v-bottom, side or dual console aluminum, similar to a Lund Pro-V? Man, I can't wait to get my 150 set up properly as I've always been disappointed with only getting 40 mph out of my '91 Alumacraft CS185.

 

[walleyehed]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

Dual console, walk-thru windshield. This would be closer to a Lund Fisherman.

 

[farginicehole]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

So it should be roughly comparable to my side 18.5' rig, weight-wise I guess. Sounds like I should have tons of thus far untapped performance. Hopefully I can get it straightened out - anxious to hear what you find out too, tysidor. . .

 

[tysidor]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

Well here is a quick update. I still haven't messed with my timing because my brother has my timing light. I want to be able to verify my timing after I set it. <br /><br />I can say this much, according to both my service manual and walleyehed my timing stop should be at 3/8 to 7/16. It is currently way off from that at just over 5/8. According to my service manual this would mean that it is way retarded. I am hoping this is the problem.<br /><br />I was able to try a OMC 15 1/2 X 15 tonight just to make sure it wasn't the cheap hustlers I was using. Still revved right upto 5000 and wouldn't go any further. The all around performance of the Hustler was superior if anyone is wondering. <br /><br />As far as my idle is concerned I turned it up to about 800-850 in gear. This helped my idle significantly. Now it starts better, idles better, and doesn't want to die when I put it in gear. Do you think this is to high? <br /><br />Thanks again for the help everyone. I will let you know as soon as I reset and test the timing.

 

[walleyehed]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

The more of the screw exposed fwd, the more the timing is advanced. With screwdriver in slot, clock-wise to retard and counter clock-wise to advance.<br />Here's the kicker....I have 3 V6's here, 2 200's and 1 175. 2 of them are 1982 and the 175 is a 1981. On one of the 200's the max timing advance screw is 3/8" longer than the other 200, and when setting up the timing after O/H, I didn't catch this until after break-in when I rechecked and reset timing...what I found at that point was the shorter of the 2 was a replacement someone had made and the initial break-in was done at 32 degs BTDC-NOT GOOD, but I got by with it due to my altitude and the fact I run 93 Octane for the break-in period...I got very lucky.

 

[Basscat 1]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

Kenny, as far as the idle problem you are having. Is it possible that your thermostat may be stuck open? Just a suggestion. I know I lived in Kansas for a while, and the water never really gets that warm there even in the summer time.<br />This is an interesting thread to me because 5000 is the max rpms I am getting on my v-4. I am currently working with the set up on mine. Hopefully somebody will figure something on this thread that may help me.

 

[walleyehed]

Re: OMC Guru's---Dhadley, Walleyehead, anyone....

T-stats are working perfect...head temps are less than 5 degs apart at max temp cycle.<br />I finally got my Idle down to 600....some Idle bleed jet changes helped me get the Idle smoothed out.