Starts but dies out immediately.

[Pete-speed]

forgot the firing order, was reminded when I saw the connections, outer cylinders-left coil, inner-right. respect Pats advice but not sure how to clean the idling and pilot circuits in the carbs. Do I have to remove them to do that or is there an easier way to flush them out? will try swapping plug wires.

[Pat Conlon]

forgot the firing order, was reminded when I saw the connections, outer cylinders-left coil, inner-right. respect Pats advice but not sure how to clean the idling and pilot circuits in the carbs. Do I have to remove them to do that or is there an easier way to flush them out? will try swapping plug wires.

Pull them, disassemble them, ultrasound them, reassemble, set floats, reinstall and balance them.

[Pete-speed]

after swapping plug wires got same result, left two cylinders cold, right two hot. should get a battery for my DMM thermocouple detector, save my fingers. anyway, does this take me back to clogged carburetor pilot circuits? and if so what would you recommend. as an aside, question about plug type was difference between the 8 and 7 version but appreciate info about RFI.

[Pete-speed]

If only way is full disassembly and ultrasonic cleaning that will relegate that to a job for the fall. no chance High pressure air into the fuel line blow thru the clog or other degumming fluid? Not lazy just don't have the time and I do have another ride.

[Pat Conlon]

Gotta take them apart. Lots of small passages.

In the old days before ultrasound cleaning we would do a multi day soak in a bucket of Berryman's carb cleaner.
https://www.autozone.com/fuel-and-engine-cleaners-additives/carburetor-and-throttle-body-cleaner/p/berryman-chem-dip-carburetor-and-parts-cleaner-96oz/139313_0_0
Then blow them out with air.

Sometimes it worked, sometimes we had to do it over.
 I've been told that the new low VOC formulation of the Berryman solution is not as effective as it was in the '80/90's.

Ultrasound is the way to go.

[86FJNJ]

I'm running my bike now with a little seafoam in the gasoline and I do think it's helping to clear the pilot circuit in the carbs. Def get that old gas out of there put some fresh gas and maybe try some seafoam in the gas. Some people fill the carbs with just seafoam and let it sit overnight and then drain it and do a mix of 75% gas 25% seafoam and run it for a few mins and let it sit again

[Pat Conlon]

Don't soak your carbs in straight Seafoam, it will damage the aluminum.

[86FJNJ]

https://seafoamworks.com/questions-and-answers/can-sea-foam-be-used-for-soaking-carburetors-solved/

It looks like Seafoam says you can soak carbs in Seafoam

[Pat Conlon]

Ok, thanks, I recall other FJ'ers warning about soaking in certain cleaners damaging the aluminum surface.
 If Seafoam does not specifically state that's it safe for aluminum soaking in full strength,  (like the Berryman's carb dip) I would be leery.

Perhaps Robert @ RPM can chime in....he's seen his share of fucked up carbs...

[RPM - Robert]

Ok, thanks, I recall other FJ'ers warning about soaking in certain cleaners damaging the aluminum surface.
 If Seafoam does not specifically state that's it safe for aluminum soaking in full strength,  (like the Berryman's carb dip) I would be leery.

Perhaps Robert @ RPM can chime in....he's seen his share of fucked up carbs...

We use the ultrasonic with chemcrest cleaning solution. After hot tanking them to get the dirt and crud off. I don't use seafoam at all so I have no clue.

[red]

Pat,
Some have tried using Simple Green to clean the bike aluminum.  Bad Plan. That stuff does damage aluminum, at the molecular level.  This damage is called Hydrogen Embrittlement.  It makes aluminum prone to cracking.  That may not be obvious with just a quick swipe with the cleaner, but it happens.  Definitely you do not want to soak anything aluminum in a bath of Simple Green.  There is a separate product, a version of Simple Green made especially for use on aluminum, which should be all that anybody needs to hear.  The makers of Simple Green are fully aware of this issue.

[Pat Conlon]

Thanks Red, now I remember you mentioning that, also IIRC there was something about a fella soaking his carbs in lacquer thinner....

let me try and find the post.

[Pete-speed]

pulled out the air box, plan to drain the float bowls, let sit for a while. any comments as to whether this is a good or bad idea. additionally, if when I disassemble the carbs, are replacement float bowl gaskets available anywhere?

[Waiex191]

Check out post 9 in my thread.
https://fjowners.com/index.php?topic=19343.msg197040#msg197040

[Pete-speed]

Read the whole carb rebuild story, guess I can fabricate gaskets if needed but heard mention of rebuild kits. Are there carb rebuild kits for a 1991 FJ 1200?