Before I dive in......

Post by **Matt** » Sun Oct 08, 2006 9:09 pm

If it is running on the lean side at idle, it will be running leaner when it gets hot at high RPMs. Because of this, you should be running a bit rich at idle, which will result in the engine loading up after a few minutes of idleing. It is normal. Here is a quote from the operators manual:

IMPORTANT: Do not permit engine to idle for long intervals. Spark plug fouling could occur. Shut off the engine whenever you stop.

Danzig · Post by **Danzig** » Sun Oct 08, 2006 9:13 pm

The needle adjustments, correct me if I am wrong, but backing them out will produce a lean condition correct?

Post by **Matt** » Sun Oct 08, 2006 9:22 pm

No, the opposite. Backing them out should allow more fuel through, making it richer.

Danzig · Post by **Danzig** » Sun Oct 08, 2006 9:23 pm

I would have to believe I am ok then? I really dont know for sure, plugs look good. Compression being high is throwing the carb off I do believe.

JDFanPa · Post by **JDFanPa** » Sun Oct 08, 2006 10:56 pm

I KNOW THAT THEY SAY 1.25 BUT THATS JUST BASELINE SETTING Idoubt you will ever have a carb work exactly there. But 5 turns in warmer weather is definatly a problem. You might end up having the screw fall out adjusting it in 20 degree weather. It sounds like you have a blockage in the idle circuit like a gummed up passage or some thing. That would explain 5 turns having to be out that far just to get enough gas to run that also would explain having to choke it to run previously. With the highside that far out it could even maybe be sucking gas through there at idle. So be careful if youve got light brown plugs now and you run it wide open in some cold weather you probably will be lookin for pistons.

The compresion is way high specialy on an old motor is your gauge good for sure does it read lower on your other sleds? Stuck rings make compresion low and I cant imagine enough carbon to raise it that much.

Danzig · Post by **Danzig** » Sun Oct 08, 2006 11:05 pm

The gauge is a couple years old MAC brand. I just used it the other day on a truck and it was accurate, I will borrow another one and see if it compares I guess. The readings on the 80 liquifire is about 135lbs if I my memory is right. If rings are stuck due to carbon deposits getting behind them and freezing them tight against the cylinder wall, I would think this is or may be the problem. Anyone got head gaskets for a 440/21? And torque specs? I would tear the heads off and look and see if I had the gaskets.

The idle circuit? I have thought of this also, but I am not up on these wahlbro's to know where too look and see for a blockage. Where on the carb would I look? I dont want a melt down that is for sure and that is what worries me.

JDFanPa · Post by **JDFanPa** » Mon Oct 09, 2006 1:49 am

Stuck rings works the oppisite of what you are thinking. Basically the cylinder wears more in the middle than top and bottom. Its only thousandth but carbon gets in the ring groove or it can be minor rust even dirt. Its the stuff in the groove above and below the ring that gets you. When rings are in the smaller part of the cylinder they can get STUCK in that position so when it travels through larger part compresion leaks by them.

In all honesty Ive had way more tillitson carbs apart on sleds than walbros and cant really tell you just where to look for a blockage. But youve become quite good at taking this apart at this time. So I would look for any type of small holes in the carb body and run some wire or torch tip cleaners through them. I remember someone posting last season about haveing to actually run a drill through a port.

The headgaskets are steel shim type Ive reused these numerous times although not [proper] it works. Its so hard to know torque specs with all the different brands Ive messed with I generaly just tighten the head blocks evenly in a crisscross pattern until good and snug once again not proper but it works. I do use a torque wrench at work on peoples vehicles so dont worry.

hope this helps some

400brian · Post by **400brian** » Mon Oct 09, 2006 2:18 am

The idle ports that let fuel pass into the carb bore, are located under the circuit plate ( the little plate held on by three screws, beside the metering lever ).
See the 3 little holes just above the center?

Paul, you didn't use all the diaphrams that came in the kit did you, I'm thinking that there are a couple that weren't used on our carb type.

Under the circuit plate, should be three items. Starting at the carb body: a thin gasket, a thick gasket, a circuit diaphram, then the plate. I'm thinking in my kit, the thin gasket was missing.

Did you adjust your metering lever, or just check it? To adjust, you bend it at the needle valve, not the end you are checking at.

400brian · Post by **400brian** » Mon Oct 09, 2006 2:38 am

According to my SM, heads are torqued to 15 -18 ft-lbs

Post by **Matt** » Mon Oct 09, 2006 7:53 am

400brian wrote: Under the circuit plate, should be three items. Starting at the carb body: a thin gasket, a thick gasket, a circuit diaphram, then the plate. I'm thinking in my kit, the thin gasket was missing.

Some carb models, and I don't remember which ones, only use 1 gasket and the diaphragm.

Danzig · Post by **Danzig** » Mon Oct 09, 2006 3:24 pm

I am getting my thoughts together and will post tonight sometime on the recent responses since last night.

Danzig · Post by **Danzig** » Mon Oct 09, 2006 8:50 pm

Ok guys thanks for taking your time on this.

The carb as Matt last stated is the way it went together, 1 thin diaphram and one thick gasket. This is what was supplied and this is also how it was prior to the rebuild.

The metering arm was bent at the needle valve, I set it rich and lean, nothing changed.

All parts were used that were supplied in carb kit per my carbs criteria. I rebuilt the carb as to the instrcutions and as the carb was prior to the rebuild.

Everything is perfectly in place, springs, adjustments, gaskets, holes are in alignment with the gaskets to the casing assemblies.

I am gonna try one thing and that is to use the old diaphrams from the old kit and see what happens. A pin hole is all it takes and who knows, the new kit may just have that.

As far as the compression, I do not know anything new, I am aware of how compression works due to being an auto mechanic also. I called a dear friend of mine, my father,also about this who has been an auto mechanic since 1969 and he also feels that stuck rings,carbon build up behind them, and possibly alot of carbon build up on the top of the pistons cause these types of problems. Granted we are not 2 cycle engine guys.........I leave that to you guys.

Another question..........what about a plugged up intake manifold or exhaust manifold? I do believe this is a reed valve engine. KEC440/21
I did not notice any obstructions in the intake when the carb was off.

Another question.........the compression check was performed by pulling the motor over about 5 times, 5 times means 5 pulls on the rope. Is this a correct way to check compression on a 2 cycle?

Could there be a possibilty that this engine was rebuilt prior to me getting my hands on it and the compression is just that?

harleysportster · Post by **harleysportster** » Mon Oct 09, 2006 10:05 pm

Paul,
The compression on a rebuild 440/22 engine is in the 135-145 range. The only difference that I am aware of between the /21 and /22 is porting. I would remove and inspect the head/top of piston for carbon.
Compression is checked holding the throttle wide open and pulling on the recoil until the max psi reading is achived. It could take 5 pulls or 10 pulls, it does not matter. As it was stated before, if you had stuck rings, the compression would be low. Are you able to blow compressed air thru all the tiny holes/orrifices of the carb or are you relying on just spray cleaner?

Danzig · Post by **Danzig** » Mon Oct 09, 2006 10:20 pm

Pat:
Compressed air was used, 110 psi.

The throttle was not held wide open.

JDFanPa · Post by **JDFanPa** » Mon Oct 09, 2006 10:39 pm

If rings stuck the way you think when the motor hit the less worn part of the cylinder it would bind/lock up the motor not to mention gouge the hell out of the cylinder. Not trying to be a know it all but how I explained it is how it is.

In the automotive feild generally stuck rings refers to oil control rings as opposed to compresion. Which causes smoking and excessive oil use. Im sure you understand that anyway just thought it might help others following this.