I'm stumped! Carburetion problems?

[shawnh62]

Hi everyone, I'm a new member here from Palm Bay, FL.  A couple weeks ago I bought a 98 Valkyrie that was hydrolocked and tore out the starter drive and idler gears.  The bike is in great shape.  Here's what I've done so far:  R&R engine, replace starter drive and idler gears, rebuilt petcock, new plugs.  While the engine was out I took each float bowl off, removed the main and slow jets to clean them.  While the bowls were off I cleaned them also.  The bike had supposedly just had the carbs cleaned/synched by the local Honda shop a month ago. 

Here's the problem.  When I try to start it it'll fire up and run, but only on the front two cylinders(1&2).  3&4 don't seem to have been firing at all.  5 and 6 backfire once in a while.  I pulled the timing cover to make sure it didn't jump time.  I'm thinking a couple things. The first is the float valve screens(if it has them) are plugged on 3&4 and partially plugged on 5&6.  The second is somewhere along the line some crap made its way down the line and plugged some jets up.  I removed the plugs and verified spark on all the cylinders.

Bike has 14k miles and has been sitting now for about a month, up until then was running each week for a short ride.

I apreciate any advice and look forward to hearing your opinions!

Shawn

[Ricky-D]

Sounds like a synchronicity issue to me!

***

[Bobbo]

Since the front two cylinders are firing, the middle two aren't, and the rear fire sometimes, I would check the connections on the coils.  Each coil fires opposing pairs of cylinders, and it sounds like a coil connection problem.
 

[98valk]

"The first is the float valve screens(if it has them) "

yes these carbs have them.

do the plugs have spark?  check firing order.

if intake manifold O-rings are leaking, not enough vacuum is generated at cranking speed and idle to pull fuel thru the carbs. get a set of viton o-rings,  http://sites.google.com/site/valkparts/.

OEM o-rs are buna-n they deform and are required to be replaced anytime the maniflods are removed.

[Madmike]

Is there fuel getting to every bowl of all carbs??

Are the plugs wet or dry when you pulled them - may help tell between a fuel or spark problem.

[9Ball]

did you remove the pilot jets and clean/inspect?  You'll also want to check to see if they are set properly.

Not a fan of cleaning the main and secondary jets...I recommend replacing.  You should start with the tank and fuel screen and work your way to the carbs to make sure there isn't rust and junk making it to the carbs.  A hydrolock meant that one or more floats were stuck, which may have been due to junk in the fuel tank and lines.

[shawnh62]

Wow, thanks for all the responses, looks like I have some work to do! 

Spark to all cylinders, coil connections good, spark plug wires routed correctly, etc...

Now to the fuel issue.  I took the carbs off tonight as I'm still convinced this is a fuel issue.  After removing the carb bowls only two were wet/full.  I wonder if I either didn't have vacuum to the petcock long enough to fill the bowls or its not working correctly?

I blew air through the fuel line and worked each float valve individually and they were working and not sticky.  The inside of these carbs are very clean.  How do you get to the top of the float valve to clean out the screens?  I was looking it over but couldn't figure it out. 

I do know the petcock is shot, getting a new one anyhow because the manual side o-ring is leaking and I can't source a new one.

Here's my plan, let me know if this sounds logical. 
1.  New pingel petcock with an inline filter installed before the carbs.
2.  Put these carbs up on the bench with gas going to them to make sure all the bowls fill and the floats shut the supply off. 
3.  Re-install with new o-rings under the manifolds.
4.  Put them back on(I can tell this is going to be fun!)
5.  GET IT RUNNING!
6.  Synchronize 'em up
7.  Ride daily for multiple years

[9Ball]

make sure you take the pilots out...you need the "D" shaped tool or need to fab one up.  Replace the pilot o-rings while you're in there and clean the passages well once the pilots are removed.  Don't lose the little brass springs and washers.

set the pilots to your liking.  Mine are at 2 1/4 turns out with stock 35 secondary jets.  I'm also at sea level.

[Bobbo]

Other things to check are the fuel tubes between the carbs.  I can’t remember if the front carbs get the fuel first, or not, but they are all in series for the fuel.  You might want to connect a vacuum pump to the petcock if it’s the stock one, and pump a vacuum on it to let the bowls fill up before starting.

Let us know when you get her running, and good luck!

[shawnh62]

Ok, I just ordered up pilot o-rings, manifold o-rings, pilot tool, pingel petcock.  I'll give it another shot next week when the parts come in!  Hopefully that's all it is.  I really appreciate the help, I'm diesel smart(ish) and gas stupid.  I'm going to make an attempt at attaching a couple pictures too. 

I'm really excited to get this thing going and take some long rides...

Shawn

[shawnh62]

[shawnh62]

[Pete]

Do not forget to clean ALL the interior passageways in the carbs, and verify with air or fluid that they are clear and clean.

[Thunderbolt]

SCREEN SET
16952-MZ0-003

make sure as has been said to blow air through all the passages.  I have cleaned up a couple of Valks that had been cleaned up once and had more junk in the lines to clog slow jets again.

I used a 1/4" short extension, big end inserted into the screen in the tank to remove it.  It just fits and if you kinda push from side to side, it will break loose from the tank, then pull slightly to the side on the extension.

[shawnh62]

Ok, I'll go through the carbs today and blow out all the passages, then wait for the petcock, etc. to come in the mail.  I put a new screen set on when I rebuilt the petcock.  Will the Honda fuel tank screen work with the pingel petcock? 

On another subject I'm thinking about the carb synch.  I hope to use 4 channel synch sticks and here's my plan.  Synch 1 and 5 to carb 3, then hook the sticks up to 2, 4, and 6 as well as 3 for reference.  Synch 2, 4, and 6 to 3.  That's the best logic I can think of with only having 4 channels.  Any advice is appreciated, I am impressed with the knowledge base on this forum already!  Thanks again for helping out a newbie.

Shawn

[9Ball]

go to Dag's website and look at the manual....it is very clear how to do the carb sync...I'm too lazy right now to look it up and compare to your method.

I use the Carbtune II and it has the 4 gauges as described in the manual.

[98valk]

Ok, I'll go through the carbs today and blow out all the passages, then wait for the petcock, etc. to come in the mail.  I put a new screen set on when I rebuilt the petcock.  Will the Honda fuel tank screen work with the pingel petcock? 

On another subject I'm thinking about the carb synch.  I hope to use 4 channel synch sticks and here's my plan.  Synch 1 and 5 to carb 3, then hook the sticks up to 2, 4, and 6 as well as 3 for reference.  Synch 2, 4, and 6 to 3.  That's the best logic I can think of with only having 4 channels.  Any advice is appreciated, I am impressed with the knowledge base on this forum already!  Thanks again for helping out a newbie.

Shawn

I like and use Twinmax for carb synch

http://www.adventuremotorcyclegear.com/twinmax-p-28.html

[shawnh62]

Well, I cleaned the carbs well including the pilot circuit.  Installed new manifold and pilot o-rings.  Today I tried starting it, same thing.  Its getting gas to all cylinders, but the spark seems pretty week on the back 4 cylinders.  They don't seem to be firing at all, except a backfire once in a while.  When I had the battery box out and the engine out is there something I could've connected back up incorrectly?  I didn't unhook any of the coil wires when I pulled the engine, but just now I made sure they were all hooked up and had good connection. 

Some other thoughts:
 - bent valve or rod on all the back 4 cylinders??  When turning over the compression seems even as it turns over, but I haven't ran a compression test either.


Right now I'm leaning towards an ignition problem, but I don't know where to start in diagnosing it.  I'd appreciate any advice!  What do you guys think?

Shawn

[Blackduck]

You say you have spark on the 2 rear coils, have you tried swapping the live wires to the coils to change which cylinders they are suppling?
Cheers Steve

[old2soon]

I might be talking out of my excretment orifice-but reading other posts-these fat gals need a full up battery to fire properly.            i've read the battery will turn the engine over but won't have enoughj to fire. Hook bike to your car or truck battery with said vehicles engine OFF. Hope this helps.

[shawnh62]

I know the battery is shot.  I have been using a set of jumper cables hooked up to my car.  I sure hope this hasn't been the problem all along!  Anyway, I'll run and get a new battery now and see if it helps. 

Shawn

[shawnh62]

Well, time for me to put foot in mouth.  The back 2 coils had the supply wires switched, so it was giving spark at the wrong time.  I assumed that since I didn't mess with them during the engine removal they were connected correctly...  The PO had the local Honda dealership "diagnose"  the bike and they quoted him 2K to fix it!  During this "diagnosis" they must have disconnected or switched the coil wires for some reason. 

Anyway, it runs awesome now!  I synched the carbs up last night and rode it around a bit.  The only thing I wasn't sure about is the fuel filter.  I installed an inline filter from autozone between the petcock and carbs.  Is it possible that this thing causes enough of a restriction where at low fuel levels it can starve for fuel? 

I appreciate everyone's help, and have a great sunday!

Shawn

[shawnh62]

Valkyrie start!	powered by Aeva

[Bobbo]

Glad you got it running!   

When I suggested a coil connection problem, I never considered they could be connected backward!     You never know what dealer mechanics will do to your bike, so I try to avoid them whenever possible!

[old2soon]

Glad ya got er fired up-sounds good. Just remember-a lot of stealers-not all but a lot want ud to finance their golf outings As always RIDE SAFE

[shawnh62]

Yeah I couldn't believe it either.  The guy who sold it to me decided to sell after the dealer quoted him a giant number for the major repair it would need from the hydrolock.  I bought it not running but it worked out for the best, plus it gave me something to do with my evenings the past few weeks. 

If anyone in FL, or anywhere for that matter needs the special deep sockets for the driveline output nut and the clutch basket nut just get ahold of me and I'd be happy to lend them out.  I bought the sockets and had a welding shop put a chunk of pipe in each one to make them extra-deep sockets, doubt I'll ever need them again(hopefully).

Glad this job didn't require any power tools as I don't have anything decent with me here in FL, just a $69.00 Black & Decker tool kit, and now a harbor freight torque wrench and 1/2" 110V impact.  Sure glad I have 30K in tools sitting in a 6' Snappy box at home in ND! 

Good day everyone, really glad I joined this forum! 

[John Schmidt]

You had just left a deposit with the PO, I was next in line if you didn't come through. I was really hoping "whoever it was" didn't make it 'cuz I really wanted it.  Glad you got it up and running, the bike sounds great. As for the coils hooked up wrong, that sure didn't occur to me either. Good luck with your new toy.

[Thunderbolt]

glad you found it.  I know some have installed the inline filter and never had problems.  I also know of people in the past that had fuel starving problems after installing one.  I don't have one so can't give personal experience, just remembering past posts.

[bogator]

  Shawn I have read on here that an inline filter does cause  problems it seems that it does not get enough gas. I have not tried it but some have. glad you got it going.----RIDE SAFE----

[John U.]

I all depends on the filter. Some have used Goldwing filters with good results. A have been running Golan hi flow filters with no starvation problems.

[shawnh62]

John, where'd you get the Golan filter for your bike?  I'm certain this luberfiner cheapie is restricting on low fuel levels. 


Shawn

[Sigrún]

John, where'd you get the Golan filter for your bike?  I'm certain this luberfiner cheapie is restricting on low fuel levels.  


Shawn

Shawn, you can also try Biker's Choice filter, it's been designed for motorcycle use and is pretty free flowing. Problem with the car / generic filters is that they are designed for a higher flow provided by gas pump, not for a gravity fed system like our bikes.  

Link to Biker's Choice