Need advice from some pros

[ChuckN]

Here's the dilemma in a nut shell.

I own a '97 Arctic Cat ZL 440 liquid. I burned up a piston due to extreme cold temps and it ran too lean.

I re-built the engine myself. 1 new piston, 2 sets of rings for both cylinders. Cylinders were honed and went through the proper procedures. Crankcase was flushed and cleaned of debris, not completely disassembled.

Carbs completely disassembled, inspected, cleaned etc.. New throttle cable with oil cable as I found a frayed oil cable. I have good plenty of good spark.

77 psi compression on both cylinders. Rings haven't seated yet.

Carbs were pressure tested, everything fine.

I have a friend who is a trained snowmobile mechanic helping me. I've spoken to a couple other Cat Master mechanics who have given advice.

Simply put. Engine is completely flooded. There is no drain plug to drain crankcase. Cat mechanic recommened tear off exhaust manifold, shut down fuel lines, tip machine completely on end and hopefully it will drain thru the exhaust ports. We did this several times.

I've had a fan blowing air through the exhaust ports, through plug holes and through the carb ports to dry it out. We did this for a couple hours last night, it fired a bit, but flooded out again.

I did use some fogging oil to help seat the pistons into the cylinders and it may have gotten into the crankcase.

The fan has been blowing since last night throughout the engine, hopefully the crankcase, and I haven't tried it today.

We've tried burning as much through, lots and lots of fuel.

Any advice why it continues to flood? We've tried what seems to be everything. Thank you.

[CatManLee]

I don't know exactly what your problem is, but I know you could try pulling the sled over with the plugs out and holding a torch next to the plug upenings. If you have alot of gas in the cylinders, this should burn it out. You need to burn the gas and oil out. But be careful, you'll get a good flame by doing this if you have alot of gas in them. This has worked for me in the past, so MAYBE it'll work for you. Good luck fixing the problem.

Also how do you know it's gas? Have you had it running at all? This is probably a long shot, but is your oil line to tight? Is your oil cable opening up more than your gas? This will cause it to foul plugs and act like it is flooded?

I ran my sled out of gas and the cylinders filled up with alot of oil. It took me a good 1/2 to burn all the extra oil out before it stopped fouling plugs. I had to take the plugs out and clean them atleast 10 times.

Sorry if none of this helps, but if it does help great.

[hanson]

Chuck-

I think you have me stumped.

If it is flooding with gas, I would say something got missed in the carb rebuild, possibly the fuel inlet valve or the little arm that the floats actuate. That little arm may have gotten bent.

If you were doing your work with a good mechanic, I doubt this was missed. If you installed a new needle & seat, I know there are some 'bad' ones out there that might not be seating right and shutting off the fuel flow. Make sure to get authentic Mikuni parts.

[ChuckN]

I've gone over the carbs probably 3 times and never find a problem. Everythings fine.

There is a lot of oil inside the cylinders, I've burned and burned and burned. The entire exhaust manifold is off and the pistons are right in sight.

There is a constant film of white/greyish oil slick on the pistons itself.

My fuel is fine. I've ran this sled over 150 miles this year until the burn up.

I have a feeling that crankcase is full of oil or fuel. Might have to tear the jugs off again and remove the stuff do it the difficult way.

I had it popping over and wanting to go, but it wouldn't commit. In all my years of dealing with snowmobile engines I have never seen this.

[Uncle Bill]

Chuck,

Pick up the lastest edition of SnowGoer magazine (March, 05)

On page 20, in the Tech Q&A, one reader asks for advice with almost the identical problem you are experiencing.

Your problem may be a leaky needle and seat, or a broken diaphram in the fuel pump.

The tech people at SG will walk you thru the most common causes and how to deal with it.

Hope this helps.

Good luck !!

[Steve Bakken]

How confident are you in the fuel pump. It sounds like you've got the carbs nailed down pretty tight, so with the volume of liquid that you're talking about here, by process of elimination my guess would be a leaky diaphram.

[Knotwood]

Try pulling the carbs off and use a blow gun to help clear it out. Turn it over, then repeat several times. Blow in thru the intake side, (I've used a piece of solid steel brake line attached to the blow gun to reach in farther). Piston should be at TDC for the cylinder you are attempting to clear. Wear goggles. Disconnect the fuel hose from the pump or block it off with a needle nose vise grips then see if you can start the engine, burn off the extra fuel. (Flooded engines are the worst!) Empty out the carbs, then see if the carbs fill up as you pull it over, note if they overflow. See if the pump is working as it should. Only reinstall the carbs if you can get the engine cleared out. It seems the compression is low (100 lbs +) and the white greyish stuff usually indicates water. Do you see droplets forming on surfaces, fuel dissipates, but water tends to puddle. Have you tried another set of plugs? Oil is an insulator, makes it harder to fire. Are the choke cables releasing all the way?

[ChuckN]

I believe the problem is there is gas and oil built up inside the crankcase, and with that issue, a motor is as flooded as it will ever be and will not run. I need to find a way to get it out.

There is always an oil slick on top and around the pistons itself.

My fuel pump should be A-1. I see no problem in it's performance and I've checked that.

Leaky needle and seat. Like I mentioned before my friend pressure tested the carbs and they came out just fine. I don't know what he did, or how he did it. I'm guessing that's what he tested for?

Thanks for the advice, I'll research further.

[lawdog]

This one is a real bugger...

I don't like that description of the oil/fluid, that sounds to me like coolant/water in the oil, which would lead me to wonder about a head gasket or a cracked block or something like that. You need to really get that mystery fluid out and check it out to make sure you know what it is before you can diagnose this I think.

[ChuckN]

I do not have a air compressor, but I'll try to find one. I was thinking of trying this.

"Empty out the carbs, then see if the carbs fill up as you pull it over, note if they overflow." - I tried this last night, no problems observed. Works normal, fuel pump appeared to be working properly.

I have never seen any indication of water, really. Nothing puddling, just a heck of a lot of oil slick in the cyliner walls and pistons. I have seen anti-freeze on the tips of my spark plugs on other machines in the past, this is not the case here.

I have tried several different plugs, new plugs, old plugs, etc...

Choke cables were checked and did not see an issue.

Here is a question I have that I just thought of, I never mentioned to my friend.

My old piston was so bad I could the small engraved arrow mark in the piston was burned off. The PTO piston arrow was pointing to the nose of the sled, so I installed the new piston the same. I suspect that is right, can someone clarify???

Thank you for your help and suggestions all. This has been a frustrating ordeal. No mechanic can take a look at my sled for like a week so I will continue troubleshooting. It's been down too long and the wife wants to go sledding this weekend.

[Knotwood]

The arrow indicates direction facing exhaust port, should be OK, has to do with the way the rings line up so the ends don't clip the intake or transfer ports. If you take a piece of T-shirt, fasten it securely to a coat hanger, can you "mop out" some of the fluid?

[ChuckN]

Cool, that's what I suspected on the piston arrow.

I've done that shirt trick, and continue to. I just cannot get into the crankcase that way without tearing the jugs off again, which if it comes down to it I will have to do it. I honestly believe that is where the problem lies. I've chatted with several mechanics-friends who state that is likely 99% of my problem. Compression will remain low and the engine will not fire with so much fluids trapped in the crankcase. I just never knew that, but never had that problem either.

I'm thinking carb cleaner sprayed through the exhaust, thru the pistons and ports to the crankcase to break up the goo and oils and then get that sled over end to drain the mess through the exhaust ports. Then dry it out, and start praying.

Gissert is letting me use his air compressor for this ordeal. What a bunch of great people here. Thanks!

I hope to report good news by tomorrow.

[Knotwood]

If you pull the carbs off, you can reach or blow into the crankcase easier. Doing one cylinder at a time, put each piston at Top Dead Center, go thru the intake side. Anything sprayed into the exhaust will probably just add to the puddling. Enough gets into and behind the bearings and accumulates, causing more problems. If you have the engine out, you could tip it onto the open port, spin over a bunch of times, and try blowing air thru intake, spark plug holes, and exhaust while pulling it over. Hold throttle wide open if you can clean it out, it may help to put a TINY amount of fuel (half a thimbleful) on top of a piston, thru plug hole, while it is on TDC for only one cylinder to prime the engine, helps get the engine a few quick revs. Don't overdo the priming method, once it starts to fire, it will throw fuel all over inside. Hold the throttle wide open, could even try disconnecting the gas to start with. Flooded engines are the worst to get going! I used to have an old JLO that I'd put in some weird size Kawasaki pistons (what can I say, they were free!), only had like 60 lbs. compression, would only start by priming the engine with compressed air and starting fluid- needless to say I got rid of it...

[Steve Bakken]

Hey, Chuck, how's your arms and shoulders feeling by now from all that pulling. I feel your pain, Here's an old trick that I used on an old Yamaha that had trouble seating the pistons after a rebuild. If you or anyone you know has a riding lawn mower, run a belt from the pully on the mower and wrap it around the outside of the clutch. (Just make sure that it's spinning the right way) and fire up the lawn mower and let 'er rip. This should give your motor enough spin to get the air moving and get some fresh air and gas into it.

[ChuckN]

Knotwood,

I did everything you mentioned by blowing it all out, and your air compressor/blower idea worked slick! I winched the sled on end and blew a lot of gunk out the carb intake and it would drain through the exhaust, a lot did drain.

I also found that blowing the air through the fuel pump compression hose fitting worked well, and there was a bolt that could get removed for the other side of the crankcase as well. That worked extremely well.

I did notice that some of the stuff blowing out resembled water, it was really hard to tell. I felt the cylinders and there was sight of water.

Right now I have determined the O rings on the head were not good. Something may have gone wrong in the assembly and now they are plain shot. I have to drive a ways to a dealer that has the parts and that is at the stage I am at right now.

[ChuckN]

I researched further after blowing out the crankcase, and you may have helped me find the culprit lawdog. See above post.

[lawdog]

Quote:

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I researched further after blowing out the crankcase, and you may have helped me find the culprit lawdog. See above post.

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Glad it seems to be working out. Probably have to admit it was more of a lucky guess on my part more than anything...

Good luck finishing this beast of a project off!!!

[ChuckN]

The stubborn Cat still would not cooperate. Tore the engine down again, cleaned, flushed, ect... I had enough after that, I brought it to a sled shop and wished them "good luck". They have all the testers to hopefully find the problem.

I will report back to let all you know..

[ChuckN]

It's been a horrible 2 week ordeal. I found a mechanic I can no longer trust and further broken parts. I took the sled back and re-built myself, again.

The culprit was the piston rings on my Arctic Cat are tapered. Most of the people I talked to did not know that, and the instructions with the piston kits I purchased never mentioned that at all. If you look at the rings closely you can see a tapered side, and a flat side. That tapered side was supposed to face upward. I installed one or 2 rings wrong, and it gave me that real low compression psi result. That's why the engine would not fire.

The sled is now running better than ever, and I learned a lot out of this ordeal.

Thanks for all the help. Hope it helps you in the future.

[Knotwood]

If you ever run across some rings with a small indentation along the outside surface, squared off, they are a scraper type, fit on the second groove, and the cut-out "corner" faces down. Any inside beveled rings face up. Almost all two stroke rings are pinned, and be careful to match up the ring ends, they only fit one way, and the pin usually won't let the piston in the hole unless they are aligned correctly. Hope you got it figgered out this time!!