1987 Evinrude 200hp outboard resto/rebuild

[dehydrated]

Re: Update 04-26-2011

Re: Update 04-26-2011

jeff, are those numbers off a temp gauge reading or infarred reading ?

 

[j_k_bisson]

Re: Update 04-26-2011

Re: Update 04-26-2011

These temps are off the head temp guage. It is the right OMC temp sender for the OMC guage. The readings are form the sender in the provided threaded hole on the head, at the bottom of the hole. 1/4" from heat source. Basically exactly where the over heat sender, horn, is located. The IR would be to the top of the t-stat housing outside head temp. Basically 3/4" to 1" away from heat source where the sender is located. So the temps might show good on a IR reading. A value of 140'f +/- 15'F

Thinking of starting a thread on this topic to get some feed back from others with this rework. Just to see what reading they get off the gage.

 

[nymack66]

Re: Update 04-26-2011

Re: Update 04-26-2011

Jeff I am using Temp senders installed in the same locations you mentioned with two gauges port and starboard on my 140 , My idle temp is 125/130 , WOT is 115/125, however I was concerned my idle temps were too low which I may figured out some day.
In honest opinion you are running hot...
You may want to verify the the accuracy of the sender, the sender needs to make contact to the block with no gap in between you can use thermal grease to fill in the air pocket between the sender and block. Use very little if not when you tighten the sender it will implode the the tip....Some folks recommended aluminum foil its your call..
Highly unlikely PowerPak is the issue you mentioned, You may need to richen up your mids by dropping them down from 50 to 48 on each carb and test ..
http://en.wikipedia.org/wiki/Thermal_grease

 

[j_k_bisson]

Re: Update 04-26-2011

Re: Update 04-26-2011

I don't think it was the contact between the sender and the head as I was getting a 130-140 at idle. It was the 1200-2000 rpm range I was getting a 185'f reading. I cut back my springs to reduce the preload on them by a 1/4" I have not tested it out on the water. The weather has been bad lately when I was able to take it out. So this should solve the problem I hope of temps. Now I am looking into the shutter/kick. I very slight but present. I want this thing to run like a perfect sewing machine, not a loses old 2 stroke outboard. LOL So I am going to change out the recirc lines due to them being too small. Then I am going to confirm the motor is position install correctly. After that its change prop time. I'm not looking for a spped boat/bass boat setup. I'm looking for a offshore fishing machine setup. So if I drop the pitch and slow down a bit oh well. I don't drive faster than 12-22 mph in wrough water anyways.

 

[nymack66]

Re: Update 04-26-2011

Re: Update 04-26-2011

If your engine is equipped with a poppet valve on the throttle arm, then remove it and check the rubber seal...
As for the Shutter/Kick see my previous post, trust me on this one, been there done that ...

 

[j_k_bisson]

Re: Update 04-26-2011

Re: Update 04-26-2011

What poppet valve? The one attached to the timer base? I'm not seeing it. As to the mid's I want to check everything on the set up before playing with the jets.

Going from a 50 to a 48 will do what? Richen or lean it? I was thinking that when it is doing it next time I would push in the enricher valve and see what happens. If it is too rich wouldn't nothing but more kicks? If too lean rpm increase. Right?

 

[nymack66]

Re: Update 04-26-2011

Re: Update 04-26-2011

What poppet valve? The one attached to the timer base? I'm not seeing it. As to the mid's I want to check everything on the set up before playing with the jets.

Going from a 50 to a 48 will do what? Richen or lean it? I was thinking that when it is doing it next time I would push in the enricher valve and see what happens. If it is too rich wouldn't nothing but more kicks? If too lean rpm increase. Right?

50 to 48 with enriched the mixture and clear up the symptoms you mentioned ...Pushing in the Choke will not make a difference...You have to change the jets ...test ..and check plugs ....
Since the mid's are "AIR" jets...smaller=richer larger=leaner the opposite is for fuel jets or your high speed ones...Post pictures of your plugs from the sides so we can have a better visual..

 

[j_k_bisson]

Re: Update 04-26-2011

Re: Update 04-26-2011

Well took it out for a good run today. Ran great but still had the same kick.

First off the mod's to the t-stat springs worked great! They lift off their seats at 1200rpms. So cutting and bending them to a 1.75" free length from a 2.0" free length worked.

Second the mid idle kick is still there. I did push in the choke and it decreased the RPM to the point it almost died. SO I am too rich. Need to lean things our. BUT I did look at the cavitation plate and I can not see it. Water is spraying up and stuff so I might need to raise the motor one hole or 1". But also I am not getting the RPM's up where they need to be. I couldn't get the motor to rev over 5100RPM and a max speed of 41 mph. This was with one 3 three year old and all my fishing equipment. But I was down to 1/2 a tank. I am running a 14.3" x 19"P prop. I think I am bogging the prop/motor in mid idle/running.

Could this be it? I'm not looking for a speed boat here, so dropping down to a 14.3 x 17"P make a difference in mid idle?

I did do a compression test when I got home and they are all the same. I also looked at the plugs and they are just darked around the tips. SO things are running/burning good. Just wet. I did re gap the plugs, two of them where 0.035" instead of the 0.040". I am also going to go through the link and sinc again just to make sure nothing moved and it's perfect.

Any thought would be great on this one.

 

[j_k_bisson]

Update 05-22-2011

Update 05-22-2011

Well finally figured it out.

Yesterday took the boat over to the local Evinrude dealer and they quickly inspected the motor mounting and cam to the conclusion that I had it mounted too far down. So I raised it up two holes on the transom mounting bracket. It cleared up some of the mid range shuddering, but not all of it. I'd say 25% of it.

So next they gave me the next size prop down. A 15" x 15"P and took that for a run. Not the max speed with a completely full tank is 39.9 mph and the rpms top out at 5600 RPM. About right. And not mid range shuttering/kicking. SO I must have been over loading the motor and it was loading up with gas.

So we are done with the motor rebuild for now, moving on to finishing the boat.

Thanks everyone who gave input in helping me to get thru this project. I have learned a lot doing this. I have never done one before and the experience was fun and challanging. But could be done by anyone with the right tools and alot of patience!

Thanks everyone again!!!!! See you on the water...................

 

[j_k_bisson]

Re: 1987 Evinrude 200hp outboard resto/rebuild

Look again to the new year and I'm already starting my planing. My main issues from last year was my mid range bogging, in the 15-20mph range. This required me to keep dropping my prop pitch to stop the motor from loading up and kicking. Not that the ice has form on my favorite fishing holes, I am reevaluating my choices for the up coming season.

I am thinking of playing with the jets for this motor. Here is what going on and my thinking. I am hoping all of the guys that where following this thread last year shime in with their considerable knowledge and lem me know if my thinking is off base and flawed.

Just to recap the motor is sort of a Frankenstien of a motor. It is a 1986 mid and lower unit bolted up to a big bore 1990 block with a 1987 electrical system. The carbs a a mistery as to what they are for bodies, but the jetting is set up for 1987 carbs.

First question is that is the difference in the carb bodies between 1986/87 small bore carb bodies to 1988-1990 carb bodies. The rebuild kits are the same. This means that the gaskets all match up. Does not say if the bores are the same. They have to be close or the oring gasket between the carbs and throttle bodies would not fit in the grove. Anyone know what the bore size for a 1988-1990 big bore looper carb diameter is?
As to the jetting here is what I found out.

1987 Main; 62d, Mids; 14, Idle; 48
1988-90 Main; 62d, Mids; 47, Idle; 34

Now correct me if I am wrong but I believe that the larger the number the larger the hole size. Goes with Number drill sizes. This would me that when the big bore blocks in 1988 to 1990 the idle jets where richened and the mids where leaned out. Is this thinking correct?
My thinking is that this would probably clean up my mid range bogging allowing me to increase my prop pitch back up from 15 x 15P to be in the proper range of 14.5x17P-21P without the mid bogging. Also would increase the speed of the boat overall. Which I would love. Please let me know by commenting.

 

[SparkieBoat]

Re: 1987 Evinrude 200hp outboard resto/rebuild

I would get trim tabs and a 15 pitch prop...5600 RPM @ WOT is a little under for my taste. I like to hit 5800-6000 RPM at WOT. (closer to 6K unloaded) I mix a little extra oil in my motors and I have never had a problem due to the slightly higher RPMs. I get better over all performance from my motors at this RPM range..and when the boat is loaded down I can still run over 5600-5700 RPMs.

 

[j_k_bisson]

Re: 1987 Evinrude 200hp outboard resto/rebuild

I would get trim tabs and a 15 pitch prop...5600 RPM @ WOT is a little under for my taste. I like to hit 5800-6000 RPM at WOT. (closer to 6K unloaded) I mix a little extra oil in my motors and I have never had a problem due to the slightly higher RPMs. I get better over all performance from my motors at this RPM range..and when the boat is loaded down I can still run over 5600-5700 RPMs.

I do have trim tabs and a 15 x 15p prop. It load in moderate to high seas in the mid range. I fish in moderate to high seas, so I want to fix this. I run XD-100 on the rich side od 50:1 ratio. Smokes like a ***** at the docks, but I don't care. My plugs do not fowl out at any range of RPM's with this ratio. I can get my boat up to 5600 RPM fully loaded with this prop. It also goes full out at 46MPH on calm water with a slight tail wind and 7 MPH current!

I'm try to get the mid range cleaned up. And while investgating I found that Evinrude changed the jetting whenn they increased the bore size of the blocks. They kept the jets that same for three years on these motors, but the 86/87 they changed them every year. Just trying to understnad if this would make a huge difference in my mid range loading...

Anyone know?

 

[SparkieBoat]

Re: 1987 Evinrude 200hp outboard resto/rebuild

you are right..they did some different stuff from 85-87 from what I understand. I am not sure how it would effect mid range..maybe experiment with some different jets.

 

[dehydrated]

Re: 1987 Evinrude 200hp outboard resto/rebuild

Where exactly is the bog rpm wise you may be too rich on the mains if you did extend to a 25 inch outdrive you might want to go down one size at a time on the mains till you get rid of bog just a thought of mine. wouldnt it of been easier to start new thread ha ha

 

[SparkieBoat]

Re: 1987 Evinrude 200hp outboard resto/rebuild

personally, I would jet for best WOT power and MPG. It would stand to reason (at least to me), if you get WOT right, the carb should be designed to then work properly through all RPM ranges. maybe try tweaking the timing some..play around with the linkage sync. I have been in many boats that seemed boggy at lower RPMs, but mostly as a result of the fact that they have more boat in the water because it is not on a full plane. nothing to do with the motor. you may be over thinking this thing. but I did not read all 274 post either...LOL

 

[j_k_bisson]

Re: 1987 Evinrude 200hp outboard resto/rebuild

Well I'll take your hints at opening a new thread on this. I'll be opening it soon. Give me some time this morning. I'm in meetings all day.

Great ideas, but I need to dive into my thinking ab bit more. I was hoping that Bobbie was going to join the discussion. We'll see if he tunes into the new thread.