TOPIC: 1966 Evinrude Starflite 100-S OB Update

This is a new thread relating to the original post titled Evinrude Starflite 100-s OB Advice. www.fiberglassics.com/glassic-forums/j-e-g-o-s-place/evinrude-starflite-100-s-ob-advice

Well, thanks to all of you for the outstanding advice... I actually reassembled, remounted the carb's, found all orignal parts thanks to this forum, completed a rebuild of the fuel pump, new plugs, cleaned points, changed lower gear oil, and, after likely 40 yrs, started her up

The only part I can not find is the automatic choke retaining ring which restricts the choke spring from rotating so while she started (and actually idled!), there is still the issue of correcting the choke settings - and some fine tuning.

I have attached some before and after shots -and one of the motor on the newly restored 1962 Crestliner Del Rio Imperial.

Cheers, Matthew

The Del Rio's looking great Matthew, glad to hear you got the old 'Rude running good too. (Almost)

Thanks Mark!

Well, she’s running – albeit roughly and with a little too much smoke for my liking, but I still have to install the retaining clip for the auto choke which is inbound from marine engine.com

Quick question for you or the Forum - I suspect the smoke is likely from sitting for so long and the serious fogging I gave it prior to the restoration, but I thought I would check to see if anyone knows the proper fuel oil ratio for this motor…

As it was a first start, I went with 50:1. Is this correct for ongoing mixtures or is there another ratio I should be using? Also, does anyone know which spark plugs should be used? Original were Champion L19V which cross ref’d to NGK BR7HS… which is what is in her now.

Thanks again to all for the help with this – very satisfying to have done all this work and have her spring to life.

Matthew

If the choke is not opening all the way it will run to rich and smoke or if you have a cylender not firing it will smoke. At that mix you should not smoke. Maybe a little right at start up.
Mike aka pathfinderz1

Mike, Many thanks for the advice.

I suspected (hoped) the choke had something to do with it, it also might be that I set the low idle needles too rich and will try to adjust them leaner. Manual said to seat them and back them off one by 3/4 of a turn. I’ll try adjusting them leaner and, try to lock down the choke.

Do you know by any chance in the initial set-up of the choke (heat activated spring) whether I should have the cold setting hold the choke plates lightly closed and let them open once the spring heats? I guess the question is, where should the initial setting hold the choke plates on a cold motor? Open or closed? The system also has a manual choke solenoid that closes the plates when activated...

Cheers,

Matthew

Fuel oil mix is recommended at 50:1. The service book I have recommends sparkplugs for the 1966 model year as Champion J4J or AC M42K or Autolite A21X with a sparkplug gap setting of 0.030. It lists recommended plugs for the 1967 and 1968 model years to be Champion L-19V or AC V40FF which it notes as having nonadjustable gaps. I'm not sure why the switch from '66 to '67, but it might have been something to do with the concurrent changeover from battery ignition to capacitor discharge.

I'm guessing the initial setting should hold the choke plates closed on the cold motor, and open the choke plates as it warms up so as to let air into the motor for continued combustion. That is the principle of the auto-choke: no need to set the choke for starting, however results may vary and it might be best to observe if the choke opens in actual operation as it should (many folks prefer the manual choke of the older Evinrude/Johnson outboards for this very reason).

Aha... thus the confusion on the plugs - thanks for sorting that out - i'll go find a set of the NGK B7S as these are the cross ref for the J4J which I could not find available.

yes, manual choke would be good right about now. I'll try fiddling with it once I have the retaining pieces for the choke housing in and the new plugs installed.

I really appreciate the insight and advice,

Cheers,

Matthew

OK, so here is the latest. Changed the plugs to NGK B7S which are the replacements for the Champion J4J – set gaps at 0.030 (Thanks Andy!)

Reduced the low idle settings to a leaner mixture.

Clamped down the auto choke housing while I wait for the correct retaining clamp so it held the flaps lightly closed.

Turned the key and, she sprang into life. Now, the idle and high RPM ranges are still rough, but not as much. Dropped it into forward gear - nicely engaged, ditto reverse so at least the ElectricShift is functioning.

Turned it off, waited, restarted, sprang to life immediately. Still rough however.

Choke seems to be functioning properly, however I still need to fine tune the low idle settings to try to smooth things out.

Now... here are some of my concerns which I would appreciate comments and advice – please :

A) on touch, cylinder 3 seems much cooler than the others. Should I check spark to all four cylinders – perhaps one is missing causing the rough idle?
Still too much smoke for my liking, but as she ran it got better
C) hesitation on rapid throttle advance (too lean?)
D) once she was to operating temp, I noticed, disturbingly, that the carb fuel overflow was dribbling fuel out (not pissing, but not dripping – enough to smell obviously) which suggests the carbs are getting too much fuel?
E) the engine has moments of smoothness and then moments of roughness at the same RPM
F) low idle not so much smoke – increase RPM (lightly revving) and much more smoke… but on revving, engine smoothes out and becomes quieter…

Anyway, there has been a great deal of success of late on this thanks to all the support and I would like to keep improving the performance so comments are WELCOME

I have a video which would allow those familiar with this engine (or any OB for that matter – which I am not) to listen to what she sounds like idling but I’m not sure how to upload…. So final piece of advice is… how might I do that


Many thaks to those who can respond, Matthew

OK so here is an attempt at loading a video file... which did not work...

Matthew, if you can post your video on you tube, then just copy and paste the address from the bar on your browser here it makes it much easier. That's how I do it, the FG forum automatically displays as you saw it in my post.

Now let me give you my two cents on your issues:

A) on touch, cylinder 3 seems much cooler than the others. Should I check spark to all four cylinders – perhaps one is missing causing the rough idle?

Definitely do a spark check. From what you're describing about your idle going rough then smooth, this would be a symptom as well as one cyl running cooler.

Still too much smoke for my liking, but as she ran it got better

That's not uncommon when reviving one, once you get all the little issues sorted out and run it a little, I think you'll find it will diminish even more. They're gonna smoke a little, that's a good thing. Mine had some idling "hickups" that stalled the motor occasionally, that eventually went away after running her a while.

C) hesitation on rapid throttle advance (too lean?)

Probably, back the idle mix screws out 1/4 turn and see if that doesn't cure that issue. (You mentioned that you leaned out the idle mix earlier, I would put that back for now.)

D) once she was to operating temp, I noticed, disturbingly, that the carb fuel overflow was dribbling fuel out (not pissing, but not dripping – enough to smell obviously) which suggests the carbs are getting too much fuel?

Sounds like your float level(s) may be set a little high. Either that or there may be a small piece of trash or something in the needle and seat. Proper float level and meticulously clean fuel are a must, raw fuel dripping out when running is dangerous. I'd pull that carb back down and check it out for sure.

You're getting close buddy, hang in there.

That's a nice looking Starflite.

Here are some answers to your questions;

Are you sure on the year of the engine and sure it is not a 90? If memory serves me at all, all of the 100 HP engines had solid state ignition. I don't believe any 100 hp engines had points. It is common to find an earlier disto mounted to one of these to get "around" having a blown up pulse pack. The packs cost hundreds of $, while the old disto is cheap. Performance will suffer some.

Be sure the reach (threaded area) of the cylinder head spark plug hole is indeed 3/8 inch deep if you are using 3/8" recah plugs. The J4J, B7S, etc. have the short (3/8") reach. The plugs in the late 100s had a longer 5/8" reach. The surface gap plugs are for Solid State ignition only - they won't fire correctly with a coil & points system.

Your engine WILL smoke. It is a crossflow of vintage design & that is just the way they are. The more you idle it, the more it will smoke.

Dont not rev it up in neutral (at least not much) Take it to the the lake or river to load test it. Leave it strapped to the trailer and just be sure the cavitation plate is a few inches below the surface. If you can find a test wheel, this is the corerect way to load test it & tune it. These do show up on Ebay once in a while.

If your engine no longer has a pulse pack and uses a regular coil, just go to kragen or some palce & buy a tachometer for an 8 cylinder car. an 8 cylinder 4 cycle car engine has the same number of firing impulses per crankshaft revolution that your 2 cycle V4 has.

Regarding the automatic choke - putting an auto choke on a 2 cycle outboard was one of the most stupid things OMC ever came up with. They finally dumped the idea in '68. Solve the problem with an electric choke from either a '67 or '68 carburator. your WILL save gas by doing this & it will run better.

Remove the sparkplug wire from the "cold" cylinder and ground it to the engine block. The best way to do this is to shove a 1/4 inch bolt into the boot, then clamp this to ground with a vise grip. Start the engine. If it does not run any better, that cylinder is dead. It could have a bad sparkplug, bad wire, cracked or shorted disto cap, reeds stuck closed with varnish, or a bad piston. Have you done a compression check?

Dear Mark, Bruce,

Thanks very much for the advice - all good.

Bruce, definitely a 1966 100-S – serial numbers confirm. I’ve attached some earlier before resto 360 pictures so you might be able to verify it’s construction and electronics. Also, yes to compression check – 120 PSI on all four. I’ll check the spark as you have suggested next but proceeded with the carb issue as when I bought it, it had been removed so I suspected that most of the issues I’m looking at stem from it’s rebuild – after all I’m a novice at this and tackling a four barrel carb is a stretch for me – but I’m getting to understand it’s nuances a little better thanks to this Forum Also, if there is a part number for the electric choke that would be really useful as it sounds as if I still have some choke issues as outlined below.

Mark - Bingo - I took the float chamber off, disassembled and found a small piece of rubber in one needle screw and seat - just enough to mess with fuel flow. Also, discovered that all floats were wildly out of level - while measured upright and inverted - as I did not have the OMC "Special Tool" fabricated one and aligned the floats to spec. Also cleaned high speed channels but did not have replacement orifice plugs - or the special tool to get them out - so had to leave them in however carb cleaner and tedious patience later, all were free flowing and clear.

Reattached the now cleaned float chamber yesterday and fired her up…. Started and ran much better but still rough – much smoother than before however - and after tweaking low idle settings a little richer, 80% of the smoke started to disappear which is terrific. Also, fuel overflow has been eliminated - which is a relief...

Then… as she warmed up, she started to get less rough and smoothed out further however with the increase in operating temp, the rev’s started to fluctuate and finally, she sputtered to a stop.

She would restart, run smooth, then quit in the same “I’m running out of fuel” kind of way. I’m perhaps suspecting that the Choke is the culprit but could be wrong. It reminds me of pulling the manual choke on a smaller OB out slowly to turn it off. So, while I think the choke installation is correct, I suspect that the setting is not. Any idea of how quickly the choke flaps should open – all things being equal – as the motor starts to warm up – when the engine dies, the flaps are almost wide open. Also discovered (while limiting this to light rapid acceleration) that the engine hesitates and in some instances then rev’s up smoothly and in others, sputters and dies.

If I pump the fuel bulb once, she will turn over for a little while and then come back to life (again virtually all the smoke has been reduced). Runs for a while, starts to falter, stalls. Pump bulb once, back to life - then repeat…

I think I’m almost there but there are obviously some tinkering that needs to be done by someone who actually knows the “tinkering that should be done” so I once again kindly ask for any suggestions and or advice so I can get over this next hurdle in the restoration of this now very pleasing motor which will I suspect be terrifically pleasing once I sort this out.

I have an opportunity to take her up to our Northern Cottage on lake Kipawa end of the month where I can get her into the water, but I would prefer to have her idle and run before I leave

Cheers,

Matthew

While I'm waiting for direction on the performance issues, how complex is it to change the water pump impeller and, is there a direct and simple route/proceedure to get this done without it becoming maddening? I have the new impeller and subplate, just need some direction - any advice from someone who has worked on this engine?

Matthew, please keep in mind I'm speaking generally here, I don't have experience with your particular model motor.

Any idea of how quickly the choke flaps should open – all things being equal – as the motor starts to warm up – when the engine dies, the flaps are almost wide open.

In normal summertime operation, the choke should only operate a few short minutes at initial start-up of the day. It sounds like yours is opening in a timely manner, so I don't think that's you problem now.

Also discovered (while limiting this to light rapid acceleration) that the engine hesitates and in some instances then rev’s up smoothly and in others, sputters and dies.

This sounds like the idle circuits need another tweak to the rich side (open, to the left). I'd probably try another 1/4 turn open, but first let's address:

If I pump the fuel bulb once, she will turn over for a little while and then come back to life (again virtually all the smoke has been reduced). Runs for a while, starts to falter, stalls. Pump bulb once, back to life - then repeat…

This sounds like either a bad fuel pump, or air getting in the fuel line. You can pull the pump apart and check the diaphram, but often the pinhole causing the problem is almost invisible to the naked eye. Also know that if you tear a gasket taking it apart, you're going to need a fuel pump rebuild kit anyway, so unless this has been done already, I would get one and put it in. Also, check the fuel line for cracks, the fittings for tightness, etc.. A small air leak will cause this same symptom. The vent is open on the gas tank right? (Don't be insulted, many of us have forgotten this little item to have it haunt us.)

how complex is it to change the water pump impeller and, is there a direct and simple route/proceedure to get this done without it becoming maddening? I have the new impeller and subplate, just need some direction - any advice from someone who has worked on this engine?

I just completed this task for the second time on my motor, it was definitely easier the second go 'round. I strongly suggest getting a manual for your motor and studying up on the particulars of yours, this is most helpful. They aren't that hard to do, just kinda tricky getting both water tubes (my V4 has two, not sure how yours is configured)lined up while getting the driveshaft splines to engage into the powerhead. At least you don't have to deal with lining up the shift linkage coupling, that rod protrudes up through the bottom cowling and connects after the lower unit is back in place. (This may or maynot be the case on yours, hence my statement about getting a manual.) Also, the impeller on the Johnson is much bigger than the one on the Merc I was used to working on, and I had a hard time getting the water pump housing down over the new impeller after it was installed on the driveshaft. I found it easier to insert the impeller into the housing, then work that assembly down over the driveshaft and into position, making sure the key was still in the keyway before pushing it home.

Hope some or all of this helps, and once again I apologize if it isn't entirely accurate or applicable to your motor.

Mark,

Many thanks,

Fuel Pump – a good thought and I anticipated that so I have already changed over the membrane and seals being sure not to puncture or tear as I rebuilt it. Seems like the pump is functioning and, certainly no offense taken – yes, the tank vent is open so I’m not pulling a vacuum

Your comment on air getting into the fuel line is interesting however as I noted that there was a small (wet only not dripping) leak where the fuel supply hose connects to the brass float chamber inlet which might be permitting some air to enter – perhaps. I will apply a screw down compression clamp instead of the original spring which has seen better days regarding tension. I’ll have to find some replacement hose for most of the fuel line supply to accommodate the new fuels – apparently the older lines do not tolerate some of the new additives – from what I hear – but also, they’re all close to fifty and frankly, if I could replace some of my own internal parts, I too would likely be better off

Re: Impeller - I have the aftermarket manual which should help so, what the hell – I’ll give it a go – I’ve come this far so why stop here – are there any OMC special tools required that you know of? (I loved coming across in the aftermarket manual as I rebuilt the carbs - which did not bother to give settings and dimensions for the float levels  “Just use the special tool as it is nearly impossible to set these carbs up without it” – which tool is no longer available… thank goodness for the original manual which bothered to show the schematic and measurements. Thanks for the advice and reassurance.

I’ll try to get to your good suggestions tomorrow and let you know how the low idle adjustments (richer) effect the operation. I should be able to get to the impeller this weekend.

Best,

Matthew

Hey Guys:

I too have a 1966 Evinrude 100-S which sits atop its original place, a 1966 Sweet 16 Evinrude Tri-Hull, which also sits atop its original trailor. My grandfather purchased it all new and recently left it to me. I am experiencing some of the same issues you have posted Del, and these forums have saved me a lot of money and headaches.
As I am a first time owner and never worked on a boat (aside from cleaning and winterizing) I was very intimidated to do my impeller myself, but with an exploded view of the parts and how they assemble I was able to tackle it with no problem. Just be mindful of the small parts like the key for the shaft-impeller, and the o-ring at the top of the shaft, the rotation of the engine when placing the impeller into the housing, and a little assembly lube in the housing.
It was my first OB procedure and went without any problems. I am still, however stalling when it reaches operating temp. so i'm not quite out of the woods yet. But again thanks to all the posts here I was able to attack it without too much fear.
Del, if you would like I can post back with the exact procedure I used to replace my impeller, I only did it 2 days ago so its still fresh in my mind.

Gary

Gary,

Welcome and many thanks indeed for piping in on this adventure. Very nice to hear that your Grandfather passed along his passion - and, from what I've been experiencing, a fine motor indeed (although I’ve yet to have the pleasure of having her out on the water - July 25th is the target .

It would be “Very Helpful" if you could go through a step by step recount of your experience in the impeller replacement - not just for me - but also for any other owners of similar motors now, and in the future - it becomes part of the ongoing resource for the site - did you take any pictures by any chance ?

I spent much of yesterday trying various small adjustments:

1. replaced the compression clamp on the fuel line to float chamber and tightened the supply lines from the tank (I have a clamp connection at the tank)

2. increased richness to on the low idle settings.

3. pulled all the plugs after running to see what was happening to them - starboard bank had black deposits - port side wet and clean (which would explain the cooler temp after running - so I pulled the distributor cap and lightly sanded all distributor to plug contcts (which showed some signs of surface contamination) including both gaps.

4. checked all distributor wires to ensure they were all seating properly.

After all these checks and slight alterations, I started her up and she caught within 4-5 seconds and came to life and while still rough, she is now not stalling when operating temp is reached. Also, the Port cylinder heads are now getting hotter (although it seems the starboard bank still hits a higher temperature (to touch) still) I'm wondering if that is partially due to the water flow entering the Port side and exiting through the Starboard?

While much improved, and it seems there is spark to the Port side, she is still not fully there. I suspect having her out on the water will help to clear up many of the remaining issues. As she starts first time consistently now I have committed to taking her -as opopsed to a fiends boat which is guaranteed to run - as it appears she close enough for some on water runs to clean things out and make adjustments under load which I have only been able to do in a task tank until now.

So, while the audio is very poor (phone video) and gives the impression of misfiring - that is just the audio cutting in and out. Towards the end of the video, I shut the motor off, restart -it is not stalling. Not sure if the quality will permit any insight as to her condition, but it's here should you find it of interest:

Some questions:

Temp Q's to touch:

should the water being ejected get hot enough to keep your hand there but be uncomfortable? And, how much by approximate volume should be ejected at idle and slightly above?

After running for some time should you be able to place your hands onto each cylinder head without burning yourself?

Is it common for the flywheel and surrounding housing to get hotter than virtually everything else you could touch?

Distributor Q’s:

If sandpaper has been used to clean contact surfaces will this sanding change the firing gap enough to mess with spark power and timing?

Plugs Q’s:

Black surface coating suggests too rich?
Wet and oily suggests weak or no spark?

So, today, I’m going to try to tackle the Impeller change thanks to all the good and helpful advice.

I would appreciate any and all comments and thoughts on what I have done so far – and really appreciate the ongoing assistance. Many thanks to all who have contributed,

Best,

Matthew

Matthew, I'd say you're getting pretty darn close bud! Sounds good, you may want to adjust your idle speed up just a fuzz. You called it exactly on all the temp questions, exit water and cyl head/block temps get almost uncomfortably warm, but not burning hot. It appears you have sufficient flow out the exhaust relief holes, but I'd go ahead with the impeller replacement just to be safe. Since Garry has been kind enough to offer you a step by step procedure, that should be quite helpful.
The flywheel area does seem to get hotter than anywhere else, I noticed that on mine during the "test tach" session.
Sanding the contacts shouldn't be any problem, as long as you didn't go crazy with it. (I'm sure you just did enough to remove the corrosion, right?)
I wouldn't worry too much about the plugs until you've had a chance to get her out on the water and run it a bit. Sounds like she's running pretty smoothly, and they'll clean out and run a bit better with some lake time, IMHO. Then you can pull the plugs and check 'em out to see what's going on with them.
Good luck man, you're doing great!

Mark - That's really pleasing to hear - thank you.

So, from what you have watched on the forum as I have gone through this process, and now heard, if this was your motor you'd feel reasonably secure in taking her out for the final tuning adjustments and to see how she settles in to some regular work after 30+ years?

I'll do the impeller and hopefully won't screw that up which would preclude a departure to the lake next Saturday...

Managed as well to convince a delightful supervisor at the ministry of Transport to allow me to register the trailer as a home built based on the "updates and improvements" (wiring and tires I made on it - so now have plates.

I'm taking the trailer and boat out for a road test to make sure everything is fine with the bearings (repacked and greased) tosee if they get hot or...

Yes, I think I am close enough - only other concern is the timing belt - while flexible, there are a cople of slight exterior cracks - and, iI have a replacement... so i quess the next question is, how difficualt and, what special tools if any on swapping them over - and, do I run the risk of messing with the timing thus requiring more ork after - or, if I'm careful not to displace the positions, can I avoid the post tuning?

Appreciate the cudo's and the help!

Matthew

if this was your motor you'd feel reasonably secure in taking her out

Yes, I would. I wouldn't venture too far from the ramp/dock/whatever for a little bit, until you're pretty certain everything is going as planned. Take a small tool kit and your cel phone with you, just in case. (Always a good idea anyway.)
That's good news about the trailer tag, that can get a little "sticky". Sounds like you got fortunate finding a sympathetic tag official.
Timing belt - I have no experience on the Johnsons, I did do a Merc "tower of power" once. The critical part IS getting the marks lined back up, it should cover it in the manual. Replacing the belt shouldn't change the timing, but it wouldn't hurt to check it afterward. I would at least make note of where your's is lined up now, as sometimes the book isn't entirely accurate. (I found this to be the case on the Merc, and I had the factory manual!) If your belt is cracked at all, I'd go ahead and change it now if it were me. It's much easier to do at home than out on the water, or even while you're on vacation trying to enjoy yourself.

Mark,

My feelings as well - tool kit, phone, close to land

Timing belt replacement according to the repair manual seems fairly straight forward so the remaining items I have to get done this week are:

Replace fuel lines
Replace Impeller
Replace Timing Belt.

Sounds like I'll have to take a day off work!

Thanks for the advice - I'll be sure to keep everyone posted and will take some video of the first launch,

Best,

Matthew