1979 100hp Johnson Javelin V4 100TLR79S will not idle

[ddiggerr]

Well I have just about had it with this outboard (1979 100hp Johnson Javelin V4 100TLR79S). I have been banging my head for over a year trying to get this thing running.

I can get it started with warmup lever, once I drop it down, it stumbles farts and crashes. It will not idle without doing this everytime. Even if I have it running with warmup lever you can here it coughing and wanting to die. I took it down to the water to try running it and it was worse.

To date this is what I have done:

NEW powerhead
NEW pistons and rings
NEW seals and gaskets
NEW water pump kit
NEW carb kits (this was a hassle as I found out the carbs were from a 150hp, going by the numbers stamped on front)
purchased another set of carbs from a 115hp and cleaned until everything looked new
I have changed out the jets and have tried .025, .027, and .028 with no change in idle
set floats according to manual and video on youtube
I have linked & synced over and over, only because I was never quite sure it was set correct (used Seloc manual)
I have tried running 25:1 and 50:1 to see if that would make a difference (NOPE)
I have tested the voltage on terminals 8 & 9 (purple wires) on the terminal strip (had 11 volts with key on and 12.4 while running)
Compression is approx 130 on all 4 cylinders
excellent spark on all 4, however, when I do get it running, I can pull both spark wires off plugs at same time on port side and will not change rpms. If I pull either wire off the starboard side motor dies)

I have even brought to a mechanic who threw in the white towel and asked me to just come and take it home .... no charge

I'm at my wits end and cannot afford to be throwing anymore money into this thing. Hopefully someone might know the problem

Thanks

 

[boobie]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

When you pull the plug wires off of the port side , will the spark jump a 7/16 " open air gap ??

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

Well I figured out the spark issue. After reading a few posts in regards to the orange and orange/blue wire, I found the port side was connected wrong. Fixed it so orange/blue wire is now connected to cyl #2 and all cylinders change idle speed when plug wires pulled one at a time.

Hmmmm ..... wonder why mechanic didn't catch that

Answer to your question, yes I have great spark using spark tester at 7/16" on all 4 cyl. now

However, still sputters when idling then dies

 

[boobie]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

How's it run now ??

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

It still coughs, spits, then pukes.

I put it to rest for the day. Now that I have the spark wires connected correctly, tomorrow I am going to try swapping jets again to see if that helps any.

 

[emdsapmgr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

Make sure the timer base is returning to the idle position as the spark advance lever moves the carb butterflies back to idle. Always possible the flywheel key is sheared. Usually the engine won't run at all when this happens, but it is possible is is off only a few degrees. You can check the timing with an inductive timing light on both the #1 and #2 cyls-see the marks on the flywheel. Both carbs have to be completely closed when at idle. If one of them is slightly open and the other is closed, you will have idle problems. These are all issues covereed in the sync and link process.

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

FLywheel key is not sheared, however, I do notice the timer base is sticky as it is not returning to where it should be, unless I push it back. I will address this later today by pulling flywheel off again.

I also have the idle advance screw turned in as far as it will go, not giving me much room to adjust. Should I adjust the throttle cam assembly to give myself room to adjust the idle advance screw?

I will post video of this thing running later today as well. Sounds horrible when running.

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

Well today I pulled of flywheel to check the timer base. Wanted to see why it is sticking and wont return to the stop. It looked a little gummed up, so I cleaned it and added a little grease to the groove where it rides along the plastic piece. It seemed to glide alot easier before I put everything back together.

Once everything was back together, there was no change. Is there suppose to be some kind of spring that pulls the throttle arm back against the stop?

Here is a video of what is happening, with the throttle cable off and then on .....

http://youtu.be/ORrXmzkDSJo

Here is the video of outboard running after everything was back together. I am currently running with the jets that were installed with carbs. As per the markings on the outside of carbs ...... port side jets are .027 and starboard jets are .028. After stating with warmup lever the throttle arm was stuck. In video when I push it back against stop it wants to die out. When I let go of it, the throttle arm pushes back on its own about 1/2"

http://youtu.be/srAUf4QdoJE

It has been running this way since the complete rebuild. I am at a loss why it is coughing and sputtering. The carbs are spotless and it seems the more I tear them apart and clean them, the worse it gets.

 

[emdsapmgr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

It's normal to get a high idle when running on the garden hose. When cold, you will also get the sputtering until the block warms up. Set the idle when the boat is floating normally in the water. Set it when running in forward gear. 650-750 rpm's. Once set correctly, it's normal to see 1000 to 1150 rpm's when idling on the trailer. How does it idle when in the water? The factory parts list shows that the idle jets for both the 85 and 100 hp 1979 engines should be 323003-which are .025. I'd suggest you go back to the original idle jets (replace all 4) and see what results you get.

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

thanks emdsapmgr, I will get it down to the water and give it a go. Any ideas on that throttle arm as why it will not return to the stop. Once it has been moved , it never returns. I cleaned all the old grease out of everything and replaced with new.

You also mention to go back and switch to the .025 jets. Those were the jets used in the original carb which had 1" throat. The carbs I have on now have a 1 3/16" throat using .027 & .028 jets. Won't the smaller size jets give me a lean condition using a larger throat size?

I have already tried this, however, because the engine is always popping and stalling out, I didn't see any change when swapping them out.

 

[emdsapmgr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

I was not aware you have the 115 hp carbs on your engine. They should work fine on your block (it's the same cubes as the 115 and 140.) The deal with the idle jets is that they are idle air bleeds-not actually jets. They work in reverse of a jet. The smaller the idle air bleed, the more fuel the engine gets to idle. The reverse is also true-the larger the idle air jet, the more air-hence less fuel.

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

Heres a thought....... since this motor was a rebuild and I am still in the breakin period. Would running it with a 25:1 mix ratio cause the engine to idle rough and run smoother with the normal 50:1 mix ??

I am just curious as I just ran out out of the 25:1 gas/oil mix and am going to give the 50:1 a run when I get a chance to look at it this weekend.

 

[emdsapmgr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

It will smoke a lot with the 25:1. That's about the only difference.
Have you checked the cyl head temps when the engine is warmed up? You've not mentioned that you replaced the thermstats.... The engine will run better if it heats up to between 145 and 150 when warmed up at idle. If the stats are stuck open, it can run cold.
It is also possible that your stator is weak. Weak stators will fire the engine, but can drop a cyl every 2 or 3 rpm's. You may want to check the stator voltage output when cranking. This website has some excellent troubshooting information: cdielectronics.com

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

now that you mention it......thermstats were changed during rebuild. I have checked heads by putting my hand on them when i've had it running for awhile and both were cool to the touch. Is there a way to test the thermstats on or off?

Off is going to be a pain as I remember having louds of fun replacing them.

 

[lexer440]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

The trouble your having is almost exactly the same as I had with a 140 V4. My cylinders were hot to touch but heat gun showed that the motor was running cool and I had an air leak in fuel line that I just could not pin down. I put new thermostats in and complete new fuel line between tank and carb, then I did sync and link again and finished tune in water. Problem gone for me.

Return to idle problem may be down to cable fit/routing not allowing full return to idle position.

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

I'm confused about the idle position not returning. I took everything apart and nothing was binding when I had it setup without any magor bends. It just won't return. Even without cables connected as in the video I posted link too abaove you can see it just wont return.

 

[Daviet]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

It looks like in your first video, that you need to adjust the knurled knob on the throttle cable to bring the linkage back to the stop.

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

Yes ... I have turned that knob almost to the end just to get it to rest against the stop. That doesn't leave me much room to adjust. I am beginning to think the cable is shot or there is a spring missing that pulls it back to the stop for idle.

Another question ...... in following picture (circled area marked #1), would adjusting this cause any issues with timing and help keep the throttle arm against the idle stop?

ANd looking at the spot marked with the arrow (#2), is this the correct embossed mark I am to line the cam roller too? I only ask because there are 2 of them close together. The other is marked "START"

 

[daselbee]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

You have a problem in the cable.
There is no spring return for the throttle linkages. It is strictly a manual return, a return which is performed by the CABLE.
When you place that cable end on the threaded post, there should be no movement.
Everything must be solid, stable and free from play, and in the idle position, the linkage must be against the idle stop screw.

It looks to me that you are able to move the linkage by hand. You should not be able to do that. It should only move
when you engage the control up at the helm.

EDIT:

The issues you are questioning are all part of the link and sync procedure. Get the link and sync done correctly, and the mis-adjustments that you are noticing will go away.
You must get a manual and go thru the steps. To difficult to describe here.

 

[ddiggerr]

Re: 1979 100hp Johnson Javelin V4 100TLR79S will not idle

So I removed carbs again and did another complete cleaning. I also changed the idle air bleeds, all to #25. I rechecked the link & sync again, as per manual. Everything looks as close to where it should as I can get it. The throttle arm is still not returning to the idle stop, however, I have adjusted everything to run at a reasonable idle speed where it is (I don't have a tach). It comes to a stop approx. 1/2" from the stop.

Another thing I noticed is that after running it for about 20 min., the port side heads were at an avg. temp of 115 F and the starboard side was avg 85 F. the water was flowing out backside of motor within a few seconds after it was started. Is this normal or is this a result of tstats stuck open?

heres a videdo of where I'm at so far .......

http://youtu.be/F4JsEADEur8

Idle still seems a bit fast, I think, but if I adjust it any lower from that point, it starts to cough and wants to stall out

UPDATE: pulled thermostat housing off this morning and found one of the plastic valves was pushed through into the housing resulting in water running freely. All put back together now with new gaskets. Was fairly simple job. Will test it out later today

ANOTHER UPDATE: fired it up and tested the temps. both sides now avg. 118 F on the heads. I also took temps on the bypass covers and they were sitting at an avg. 155 F and when I throttle up this temp climbed to an avg 178 F ... should I be alarmed of this temp? No alarms went off on boat.

Boat still won't idle down without sputtering like it wants to stall. I give up trying to figure that problem out. Taking it down to lake in 2 days and will play with it in the water. Hopefully the idle will come down enough once in the water, so I don't rip out reverse when backing boat off trailer