evinrude 1978 85hp,compression,reed,starting

[allenx1966]

looks like this is the place to be to get my learn on! take it easy on me,im new.
Im totally new to boating and starting out with an old motor just to see if i like boating. So far im very thrilled to be a boater! I know very little about marine engines,especially 2 cycle,but learning quickly. I do have a good mechanical knowledge for regular automotive engines.

here is my question. i have a 16ft tri-hull boat that im using to tube with and chase down waves to jump, thats about all i can say about what i am into so far. it has a 1978 Evinrude 85hp ( model 85895c ).
had a leaking fuel line just below fuel pump, i replaced all the fuel lines and it fixed that and basically runs great now. The motor has all the factory paint on it and has never been torn into. I did a compression test, all 4 cylinders are about 115 psi. all 4 plugs look good, no fouling or and issues showing up with them. I do have trouble starting it,i tried all kinds of ways of choking and pumping the fuel line ball and throttle positions,but it still won't start without a small shot of starting fluid. After using a bit of starting fluid,she fires right up,and never needs another shot of starting fluid the rest of the day. i think the fuel pump is fine because after forgeting to open the vent on my fuel tank,it almost sucked the plastic fuel tank flat (dummy). at idle,it runs fairly smooth,it sputers very slightly,but seems like the the typical 2 cycle sputer to me,maybe im wrong. I have also been reading discussions on reed valves which i know nothing about. I'm considering getting the Boysen reeds part #144. im not really out to bore anything out or go crazy building up this engine, but i do like a motor to do all it can do and run as best it can.
1) how can i get it to start without starting fluid?
2) is 115 psi on all 4 cylinders bad,good,or excellent ?
3) what would the Boysen reeds do for me? increase horsepower?
maybe help it start better?
4) are reeds very hard to install?
5) whats the best octane and 2 cycle oil to use? (been runnin 89 oct and
penzoil synthetic blend 2 cycle)
6) anyone know where i can get iridium plugs that fit,can't seem to find
any part numbers from any plug maker that fit. Are the iridium plugs
worth it?
7) been thinking of getting a used seadoo sporster/speedster 150. they
come with the Rotex motor, any thoughts on that boat and motor?
seems like it would be a great boat for getting squirrely on the water

ok, i think thats enough for my first posting,hope i didn't bore anyone!
allen

 

[wildmaninal]

Re: evinrude 1978 85hp,compression,reed,starting

I have the exact same motor. I cleaned the carbs on mine when I first bought it after sitting for years and it started right up and runs fine. I would clean the carbs (soak in carb cleaning solution for a day). The carbs are not hard to do. Compressions better then my motor, mine is 105 on all and I was told that is good, 130psi is supposed to be great. I run regular gass/ I hear I am supposed to be using high test but allot of people use regular, I run synthetic 2 cycle oil 50 to 1 ratio/mix. Don't run no chainsaw oil in it. I hear the reads are not hard to replace, never done those, I have a vidoe on my computer of how to rebuild the carbs but I can't up load that big of a file size. I don't believe in those type of spark plug myself you might be able to find some on this site. I would address the water pump impeller, I will be doing the same when I get my boat back, I hear they rot after 2 years they are just rubber. If you want to sell that motor anytime just keep me in mind.

 

[allenx1966]

Re: evinrude 1978 85hp,compression,reed,starting

thats funny, a guy at work told me to never mess with the carbs, it will never run the same...
so you mean remove the carb from the engine,soak it in carb/choke cleaner?
i just bought this late summer, and the carb has no fliter of case for a filter. i stopped at a so called evinrude dealer and he said it was no big deal, he said the factory filter was all that good anyway,and that the air should be clean on the lake.

 

[jimmbo]

Re: evinrude 1978 85hp,compression,reed,starting

Welcome to iboats

1) how can i get it to start without starting fluid?

Make sure the carbs are clean, floats are good and set correctly, Choke closes fully, has good properly gapped plugs and a good ignition system., and cranks fast enough.
Starting fluid in a 2 stroke is a no no. Since there is passage of air/fuel though the crankcase it could ignite there instead of the combustion chamber, plus ether does wash the oil off surfaces.

2) is 115 psi on all 4 cylinders bad,good,or excellent ?

good, they are even that's more important

3) what would the Boysen reeds do for me? increase horsepower?
maybe help it start better?

Some say they get more rpms, but usually they help throttle response at low rpm. Downside is they have a limited lifespan. Aslio they don't survive backfire well



4) are reeds very hard to install?

no, but care has to be taken


5) whats the best octane and 2 cycle oil to use? (been runnin 89 oct and
penzoil synthetic blend 2 cycle)

89 should be fine, avoid gas with ethanol added, as long as the oil has TC-W3 rating it will be fine

6) anyone know where i can get iridium plugs that fit,can't seem to find
any part numbers from any plug maker that fit. Are the iridium plugs
worth it?

no, to both questions

7) been thinking of getting a used seadoo sporster/speedster 150. they
come with the Rotex motor, any thoughts on that boat and motor?
seems like it would be a great boat for getting squirrely on the water


no knowledge

 

[wildmaninal]

Re: evinrude 1978 85hp,compression,reed,starting

Check out my boat restore site I have a bunch of great links in there http://www.freewebs.com/wild1979inal

The only thing you got to do on the carbs is don't loose the parts. The float should be even with the bottom of the carb (with the bowl off), if not adjust it. Take and blow out the ports on the carb after soaking them blow them out with an air gun. Check out the link for Combhouse.com under my links in my website, you may also want to do this modification to your motor.

 

[wildmaninal]

Re: evinrude 1978 85hp,compression,reed,starting

Sorry Jimmbo lol, we met up about the same time on the replies. The filter is in the fuel pump allen, be ware and don't take the whole fuel pump apart as for the filter is located under that plastic cover with the fuel line hooked to it and one scew holding it on. Its just a round screen. Before I cleaned the carbs on my motor I did use starter fluid (my dad's idea) but I reverted and started using mixed gas (mixed with 2cycle oil) in a spray bottle to start the motor, because I was werry of using the starter fluid.

 

[1730V]

Re: evinrude 1978 85hp,compression,reed,starting

1. Rebuild the carbs. It's easy. If you buy OMC/Bombardier kits the instructions are usually in them. Disassemble th carbs in an old pan or throw away roasting dish. It saves you from losing parts.

2. Throw that can of starting fluid as far as you can.

3. 87 Octane fuel is fine with a good TCW-3 oil.

4. Use the correct Champion plugs.

5. Tell the guy at work, unless he's your boss, that he is clueless.

6. Service the water pump while you're at it.

7. Decarb it too. Instructions in link below.

That engine is just about bulletproof with reasonable care.

http://forums.iboats.com/showthread.php?t=158076

 

[tashasdaddy]

Re: evinrude 1978 85hp,compression,reed,starting

seadoo is a seaDON"T. that's all i will say as an owner of a PWC with that motor. throw the starting fluid away, use some of the premixed gas, instead.

 

[F_R]

Re: evinrude 1978 85hp,compression,reed,starting

Since the motor runs OK once started, there might not be anything wrong with the carbs. It is more likely a choke problem. Try "helping" the choke by holding some light finger pressure on it. Without looking it up, I think that one has the two-stage choke on it. If the finger pressure helps, come back for some info on checking/rewireing the choke.

 

[ezeke]

Re: evinrude 1978 85hp,compression,reed,starting

Edit

 

[allenx1966]

Re: evinrude 1978 85hp,compression,reed,starting

once it starts,it runs and restarts just fine the rest of the day. i know starting fluid is not good,so when i use it,i only give a very small shot. i have seen the choke working when i press the key in,and it seems to be adjusted properly.
i think i may just rebuild the carb, i used to be good at that as a younger man ,im sure i still have the ability.

i already cleaned the fuel filter screen on the fuel pump. i repleced every fuel line and ball from the top of the tank,all the way to and from the fuel pump. all fuel lines are new.

i did try to adjust the choke once,i marked where it was at so i could revert the setting it was on. adjusting choke did nothing.

oh and by the way, you guys rock! usually when i go to a forum for questions,i get tons of idiots and arguments. you guys seem pretty cool. THANKS

 

[F_R]

Re: evinrude 1978 85hp,compression,reed,starting

OK, you seem reluctant to believe me, so I checked and as near as I can tell the '78 no longer had the two-stage choke. That's good.

However, I still am not satisfied that the choke is not the problem an should be further checked before you go ripping into the carburetors.

There is an adjustable link between the upper and lower carbs. It must be adjusted so that the choke solenoid slaps BOTH carb chokes shut tight. Likewise, the solenoid has to be adjusted up or down to close them tight.

The choke solenoid must activate when you push the key switch. And it must STAY activated when you push and turn the key to crank the starter. If the chokes are not closed while cranking, it will never cold-start.

If you still want to tear into the carbs, go ahead. But I still say there is nothing wrong with them or it wouldn't run and start right the rest of the day after the initial cold start-up.

 

[ezeke]

Re: evinrude 1978 85hp,compression,reed,starting

Edit

 

[F_R]

Re: evinrude 1978 85hp,compression,reed,starting

Just thinking, it is possible that we are attacking this from entirely the wrong angle. That motor has to crank at 300 rpm in order to get enough spark to start. Is it possible that you are cranking too slow because of a weak battery and when it runs awhile and warms up and gets some charge in the battery, it spins faster?

You can't just assume with these things.

 

[allenx1966]

Re: evinrude 1978 85hp,compression,reed,starting

F R , i think the battery is weak,but i charge it the night before i head to the lake,and i also use a black and decker booster thing a ma jig,lol. anyway,i can crank it for 5 minutes if need be, so im sure its not the battery. i think your right about the choke, i will go revisit that. it does have 1 solenoid and has the linkage you spoke of. i did mess with the linkage and adjustments alot,maybe i just didnt get it right.
i do know one thing i didnt ask about the choke. a buddy at work told me some boat expert told him that i must push that choke switch in, and make it open and close 15 times before trying to start. that was not just his advice for me, it was for all outboards with electric choke. i thought it sounded silly, but i tried it,and well, it didnt help as i suspected.
here is where i bet ya can really help. ok, take for instance my 2 cycle leaf blower or weed eater, to start them when cold, i have to choke them till they try to start, then once they try,i have to back the choke off half way,and they fire right up,then after maybe a minute,i can shut off choke completely. now.... they say there is no such thing as a dumb question, but how is the best way to choke my evinrude? keep in mind,the switch is built into my key,as i turn the key,i have to push it in to activate choke. there is no middle ground for this choke, its on or off. so maybe i should take the same approach sorta like on my leaf blower? turn key,hold choke at same time while the motor cranks, and soon as i hear it try to fire, then back off the choke?

 

[wildmaninal]

Re: evinrude 1978 85hp,compression,reed,starting

There are threads posted on what is the propper method of starting the motor. I know that you have the idle lever up while cranking then choke it but I can't remember how many times. Try and do a search on starting methods and see what it comes up with. I honestly haven't had to much of a problem with my 78 85hp evinrude after I cleaned the carbs so I didn't need no method, although I haven't ran it much because I havn't got the boat ready to go on the water, when I had it running it was running on muffs. I only paid $450 for the evinrude.

 

[rwrioux]

Re: evinrude 1978 85hp,compression,reed,starting

I think that you might find a spring on choke plunger.The spring get week and lets choke plate open thus no choke. Check and see if spring is there. I would hard connect or wire the choke plunger and instant fix. The spring will let the plate open and you with not be able to start. This happened to me and a trained mechanic could not fix this.


RWR

 

[iwombat]

Re: evinrude 1978 85hp,compression,reed,starting

As for starting technique. My '77 has the same setup.

Pump bulb
Lever up
Push in choke
Turn key

When it pops and gets going, let the key return to the on position and keep bumping the key in (choking) until it can sustain itself on high idle. Let it warm up a couple of minutes and back the idle lever down.

It's not perfect, but it works pretty well. You should really have no problems starting it cold if everything is working properly. Mine's a bit finicky at times, but it never takes more than about three tries on the most cantankerous of days.

 

[ezeke]

Re: evinrude 1978 85hp,compression,reed,starting

Edit

 

[allenx1966]

Re: evinrude 1978 85hp,compression,reed,starting

i forgot all about making this post last year. i took everyone's advice on not using starting fluid. come to find out, it was my battery. my old battery was working, charging and holding charge, but for some reason just wasn't cranking fast enough. i suspect it was just a junk battery that the man i bought the boat from just threw in to get rid of. so now i got a big "energizer" starting/deep cycle bat from sams club that works really well. just hold the key in for choke, and bam, she fires everytime! no more starting fluid.

ever since i found and fixed leaking fuel lines under the motor cover , she has been running great!