UPDATED and FIXED! Like It Never Ends: Carb Issues

[jtexas]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Ok, backed the idle jets out a bit..

HOLD EVERYTHING!

Screw the idle jets in tight, and don't back 'em out. That is definately not an "adjustable slow speed mixture" screw.

I do have a manual, and while it is very helpful, it is also very lacking in day to day experiences. ...doesn't really get into details on how to fix.

yup, if a mechanic finds a crack like that, he just reaches back off the shelf and adds "one new carburetor" to your invoice.

I've read that we should not soak our carbs because it strips some factory coating off of the body.

The 1978 carbs are ok for sure. I can't speak for late-model engines though. Some of my car engine parts (throttle-body for example) specifically mention a teflon coating that can be damaged by carb cleaner.

Unless the manual for your specific motor says the carb is coated, my advice is soak it (metal parts only) in the harshest carb cleaner you can find, like B-12. If it is coated, I'd still soak it but in something a little kinder and gentler.

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

The 1978 carbs are ok for sure. I can't speak for late-model engines though. Some of my car engine parts (throttle-body for example) specifically mention a teflon coating that can be damaged by carb cleaner.

Unless the manual for your specific motor says the carb is coated, my advice is soak it (metal parts only) in the harshest carb cleaner you can find, like B-12. If it is coated, I'd still soak it but in something a little kinder and gentler.

I soaked the drain bowls, low speed jets, and high speed jets in B-12. That crap is strong! I thought I had already cleaned them pretty thoroughly with aerosol carb cleaner, but the overnight soak in B-12 showed that there was still quite a bit of crud under there.

I screwed the idle jets back in, and seated them gently. One manual calls them idle orifice's, and another calls them intermediate orifices, I call them cleaned and re-installed.

The JB Weld is looking pretty good. I'll post a pic here in a bit. I'm going to let it cure a good 18 hours, possible 24 hours before I try to run it, so I'll probably know tomorrow how it does. That's a long time to keep my fingers crossed.

 

[jtexas]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

...
I screwed the idle jets back in, and seated them gently. One manual calls them idle orifice's, and another calls them intermediate orifices, I call them cleaned and re-installed.
...

If it's a seloc manual, I'm not surprised...seloc doesn't know which carbs are on my motor, either. Some OMC carbs have idle, intermediate (AKA "off-idle") and hi-speed orfices, others just have "idle" (AKA "slow speed") and hi-speed.

Those jets should be in there pretty tight. If you don't have a jet removal tool, the "carb rebuilding" link in the "Top Secret" thread includes directions on how to fabricate one. Best not to use a regular screwdriver on that soft brass.

In your pic I don't see a screw plug covering the idle orifice; some have 'em, some don't. Those with screw plugs are metering fuel, and will run rich if the orifice is not tight enough (or if too large a jet is installed); those without a screw plug are metering air and will run lean.

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

In your pic I don't see a screw plug covering the idle orifice; some have 'em, some don't. Those with screw plugs are metering fuel, and will run rich if the orifice is not tight enough (or if too large a jet is installed); those without a screw plug are metering air and will run lean.

I made a jet removal tool per the secret files. And it works great!

There are screw plugs that cover the idle orifices. There are two on them. Looking at the pic above, they are on either side, towards the bottom of the main carb body. The idle orifices lead to the chamber under the frost plugs. If you're talking about the opening top dead center of the carb body, that is just an empty tube.

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Here's the JB Weld fix.

 

[tal]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

There is a ton of johnson carbs on ebay right now. You might get lucky and find one that is in good shape and fits your application.

 

[Mntom]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Looks good! Let us know how it works out!

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Well it starts and runs better now. But at low speed, even when it's warmed up, it backfires through the exhaust, and if it doesn't die, it does on the next backfire. It's very apparent it's through the exhaust.

On a possibly related note, I'm not sure the left side cylinders are firing. I've gone through the ignition coils and powerpacks back a couple of weeks ago. I'm getting spark on all 4 cylinders. If you pull a spark plug boot from the right side while it's running, it shocks you and dies. On the left side, the bottom plug does the same thing but the top plug doesn't shock you. It does, however, have a good spark. I'll be spark testing tomorrow...

The right side plugs have a very thin coating of oil (brand new spark plugs). The left side plugs have substantially more oil on them. Also, I know it isn't very scientific, but the right cylinder bank is much warmer to the touch than the left bank.

It still acts like it's running rich, so I'll start replacing fuel line and the quick connects. Probably won't help, but it needs it anyway.

I appreciate all the help so far, any other suggestions?

 

[jimdd810]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

sync and lync. sounds as if its still burning rich readjust the carbs.

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

I don't think there is a way to adjust the carbs. All the jets are fixed.

 

[Lion hunter]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Get a spark tester and check for a good blue spark that jumps a 7/16" gap on every plug. If you have a timing light you can hook it up and check for spark consistency. Verify timing. Last I would test on mixed fuel from a portable tank. And the last thing may be a long shot but the cracked body tells me somebody has probably been in those cards before. Being unfamiliar with those I'm guessing here but I'd check the orifice #'s and make sure they are the right size and someone has not damged one of them trying to take it out or clean it. And I know jets can be drilled out to make bigger and aviod buying the right one. If someone has done that it will be hard to tell.

As for the right side being warmer, from what I have read this is common. My v-4 does this. Something to do with the location of the pee-hole tube (if it even has one) is on the bottom of the right bank. This allows a pocket of air to get trapped in the upper part of the water jacket. Look through the top secret file. I beleive in the post about adding a pee-hole it mentions routing existing tube to a better location.

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Ok, I watched a video while researching my problem.

http://www.youtube.com/watch?v=ffILtMUmTfY

My outboard is essentially doing the same thing, only it's a bit louder. Lots of smoke, outboard kinda moves to the side, but mine dies when it's at low idle.

Maybe mine is louder because it is a larger engine?

So, thinking that my outboard is actually being affected by a "lean sneeze" instead of a "rich backfire", what would be some things to check?

Fuel lines for sure. New fuel lines and connectors. Using another gas tank with the new fuel lines.

Would a lean condition leave oil on the plugs?

 

[clanton]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Check the isolation diode in each power pack. Check between A and D termial of 4 wire power pack connector.

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Check the isolation diode in each power pack. Check between A and D termial of 4 wire power pack connector.

Clanton, what would be the correct way to do that?

I took it out again today and it's still bogging at WOT. It's starting ok, idling ok, still sneezing a bit.

I'm beginning to get a bit frustrated. I'm giving it a few more days then it goes into the boat shop.

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

So I hooked up an inline spark tester, the kind with the light in the middle. I had consistent spark on all 4 cylinders. I'll be using a gap tester tomorrow.

Anymore ideas?

 

[misery]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

I was experiencing almost the exact same symptoms as you are now with my 90 hp evinrude. I had spark on all the cylinders, as tested with a spark tester set to a 7/16" gap. One side of the motor was quite a bit cooler than the other side. To trouble shoot the problem after i had checked all the basics i swapped the coil packs from side to side and the problem followed the coil pack. i put on a used coil pack a friend had and..... voila! a perfect running motor. Sometimes you can over think the problem.

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Misery, when you say coil pack do you mean Power Pack or Ignition Coil?

 

[bob johnson]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

before you go throwing money at coils and expensive electrical parts check this.

run your motor on muffs one night and with all the lights in the area off, see if you have a short jumping anywhere off your plug wires.

I had a motor( 2 cylinder so it was more noticable) that acted so funny then wouldnt... I finally discovered a plug wire was shorting out when it layed close to the block... and when you put the tight cover on it was always pushing stuff closer to the block...new wires solved the problem.

I though of that when you mentioned you got a shock while holding some plug wires and not when you help the other...BUT you say you have spark

maybe you have more bad plug wires than good!

just check its free and easy

good luck

beyond that a misfire into the exhaust sounds like a timing issue as well


bob

 

[Ranger Danger]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Thanks bob. I did notice tonight when I was using the inline spark tester that I saw a very slight spark around my terminal block, but it was only for a second and it didn't happen again. I couldn't track it down, but I did wrap some electrical tape around a few wires that were cracked on the terminal block earlier in the day.

I do agree that the timing is more than likely off. That would certainly cause some issues.

It's about to storm here in southern Oklahoma, so I'll be back at it tomorrow.

 

[bob johnson]

Re: Like It Never Ends: Carb Issues

Re: Like It Never Ends: Carb Issues

Thanks bob. I did notice tonight when I was using the inline spark tester that I saw a very slight spark around my terminal block, but it was only for a second and it didn't happen again. I couldn't track it down, but I did wrap some electrical tape around a few wires that were cracked on the terminal block earlier in the day.

I do agree that the timing is more than likely off. That would certainly cause some issues.

It's about to storm here in southern Oklahoma, so I'll be back at it tomorrow.

forget the tape, it never worked on my motor...new plug wires!!!!!!!!!!!!!!!!!!!

bob