Clark Michigan 35A Hesitation/no power

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Back wrenching on the machine.

Pulled and resealed the steering gear so the machine doesn't hemmorage oil all over now.

A friend of mine who works in John Deere Dealer Technical Assistance Center called out a leaky throttle shaft on the running symptoms. There is significant play in the throttle shaft, more than 1/16.

Going to try to tighten it up and or seal it.

It isn't a significant leak, but it's enough to pay attention to it.
 
So this summer I only used the machine a handful of times. It ran fine. As soon as it got cold again, same symptoms as last year!!!!

I fiiiiiiinally got it started, pounded on it, ran it out of fuel, drained the carb bowl and fuel filter and poured in fresh gas. It looks like I won't be getting fuel at my local station anymore. The machine starts and runs great now on no ethanol 91 gas.

I'm assuming that the new fuels hold the water in emulsion better so it doesn't create the "jelly" like before, eventually just causing systemic running issues with emulsified water. The carb and filters had no obvious debris or issues.
 
So is the timing via vacuum advance? I would really suspect a diaphragm issue in the distributor. Also have you pulled the distributor completely and checked for wear at the gear on the distributor?
 
BigMatt,

The distributor is a Pertronix HEI unit almost new compared to the rest of the machine. I lubricated the slides on the swing weights/cams on the advance and filed out the ridges in them for smooth advance, just in case it was sticking, but it didn't help. I read up on faulty HEI modules but the symptoms and the timing light behavior didn't coincide with those failures exactly. When I put a timing light on it, it advanced aggressively with throttle app but the machine would fall on its face and misfire. I replaced the cap and rotor with no improvement.

Essentially, the water in the fuel is not sitting on the bottom... Its IN the fuel completely emulsified to the point where the machine would barely run. the water drain on a LARGE fuel filter and the carb had nothing! Good fuel and problem solved.
 
Again with the running issues gah. This time, I may have done it in. Didn't trust the oil pressure sensor and was running it very low on oil, hasn't burned a drop for years, and I had recently checked it. Added some, ran it a little.. Changed the oil and it did not look good, haven't been able to screen it out to see if there is metallic debris.
Now I have low power and smoke, and a bad coolant hose to boot. Going to do a compression test :( Could be fuel issues again, but have run close to 20 gallons of fresh fuel through the machine lately.
 
January: The loader would not run. Found a plugged hydraulic filter.

Today: Loader started and ran, then stopped. Getting fuel, spark and air, but won't run past low, low idle f or 5 seconds. Hydraulic filter fine.
 
Checked plugs: black but easily cleaned, soft black carbon.
Compression:
1: 90 psi
2: 90 psi
3: 90 psi
4: 90 psi
5: 40 psi
6: 30 psi.
Spark: makes a healthy snap enough to see it in the daytime and ignite any cleaner on the tip. Coil read 11.7 volts across the terminals and that also feeds the HEI module, so that should be good ..
Carb: gas everywhere...but none seems to be making it up to the combustion chambers. Plugs are dry even if you hold the choke and crank for 30 seconds.
Engine won't run on ether sprayed into the carb or on the other side of the carb into the intake. Best I get is 5-6 seconds of low stumbling idle at random times. If it does give me 5-6 seconds, it doesn't help, seems to piss it off. it might not fire again and run like that for a few minutes.
Hydraulic filter: was clean as a whistle and flowed just as well with a filter as without.

Things left to check:
Transmission filter could be plugged, but crank speed says different. Like the main hydraulic should be able to stop the engine.
Remove and clean carb/intake???
 
Your engine needs rebuilt, that compression is too low,
and the two worst cylinders are obviously loosing compression
even more, head gasket gone or broken rings, which will get worse
with every run, until it won't run at all.
11.7 volts is not good on a system that should read over 12.
 
That's a good assessment a possible blown head gasket. Compression exchange could be blowing back thought and keeping gas from coming up the updraft tower. which includes a govenor throat. I don't have the time or resources to do a full rebuild, but if the HG is just bad, thats doable. I had read that these motors were extremely prone to that because the head is long and thin.. Found at least one used core engine with the same 2 cylinders bad.

Keep in mind, these engines are only 6 to 1 compression and can run on 78 octane fuel. 90 psi might be a good number for the rest of the cylinders. It DID run pretty good until last summer, when it suddenly started to smoke and acted like it (shocker) didn't want to start.

Ignition switch and harness has been a problem before but I don't think that's the issue at the moment.

Wish I knew what kind of engine I could replace this one with to go to something more reliable.
 
That's a good assessment a possible blown head gasket. Compression exchange could be blowing back thought and keeping gas from coming up the updraft tower. which includes a govenor throat. I don't have the time or resources to do a full rebuild, but if the HG is just bad, thats doable. I had read that these motors were extremely prone to that because the head is long and thin.. Found at least one used core engine with the same 2 cylinders bad.

Keep in mind, these engines are only 6 to 1 compression and can run on 78 octane fuel. 90 psi might be a good number for the rest of the cylinders. It DID run pretty good until last summer, when it suddenly started to smoke and acted like it (shocker) didn't want to start.

Ignition switch and harness has been a problem before but I don't think that's the issue at the moment.

Wish I knew what kind of engine I could replace this one with to go to something more reliable.
Well if I was in your nick of the woods, I would be all over that engine,
and it wouldn't be to earn money but help a fellow brother.
May be someone will step up and help you sort these issues once and for all.
 
Seen a lot of engines ruined by that transistor ignition stuff!--- that F-226 was a great motor----dad an I had several of them. I would say that you have now junked the motor, so go ahead and have a major re-build done by a pro shop and you will be good for many years to come.
 
Seen a lot of engines ruined by that transistor ignition stuff!--- that F-226 was a great motor----dad an I had several of them. I would say that you have now junked the motor, so go ahead and have a major re-build done by a pro shop and you will be good for many years to come.
Why does it destroy the engine? It was one of the few things that actually made the machine more reliable. The machine ran with no manifold gasket for many years and had dozens of sets of points, (which seemed to go out and a multitiude of other abuse at the hands of my grandad. We put a new manifold, gasket, and the pertronix distributor including a new distributor shaft. Before all that, it was generally very hard to start, now if all systems go it generally doesn't need the choke at all in the summer and only a few moments in the winter.

A blown headgasket is barely a junked motor... Having someone else work on it, except for head machining is really out of the question. Out of all scenarios, the blown headgasket is the most likely scenario for the compression issue, if it is an issue at all once the engine runs/gets warm/lube. The compression test was done cold because the engine wouldn't run...

We did get the engine to run. Dad put his hand over the carb. With EXTREME vacuum, the engine would pull enough fuel to run.

So we pulled the carb and he checked it out. Said it was pretty clean (we pulled it in January too) but the main jet might have had something in it. Since the main jet is 2 piece we hadn't taken the internal piece set into the carb bowl out before to clean besides external cleaning. Hopefully that does the trick. Definitely not enough dirt to be a smoking gun but we'll see once its on the machine.
 
Well if I was in your nick of the woods, I would be all over that engine,
and it wouldn't be to earn money but help a fellow brother.
May be someone will step up and help you sort these issues once and for all.
It is a frustrating machine thats for sure. I do have all the manuals and a good support system, my dad who has worked on it since the 80's. The old mechanic that used to work on it in the 60's and rebuilt it in the 70's is still around! We do call him on occasion to help if we get stumped.

Thanks for the support!
 
The carburetor cleaning has helped only some. The machine will run normally but doesn't stay running consistently. It certainly is still hard to start (when running properly will fire with a 1 sec starter bump). I got it running well enough. Topped up the coolant and oil. Maybe a mistake... It died shortly after.

Got running again drove it a bit but it quickly went crappy. Ran it out of fuel off level trying to get closer to the shop, and I had no fuel left on the farm. Either has a snoot full of bad fuel still (and that's my problem, again) or it's pulling antifreeze in bad enough to put out the fire... I cannot tell in the exhaust smoke. Went and got a bunch of fresh no ethanol 91 and we will see what happens next.
 
Over time the fuel will wear the carb jets larger. not many think about that anymore because of all the fuel injection stuff. also the pick up coil in the solid state ignitions systems can become intermittent or just plain finicky. static tests do not show this. had one where it would run fine cold but as soon as it got hot it would go open. have had spark coils do about the same thing as well.
 
Blades, well, this is possible that it's worn out. However, right now the last the machine was running and that little bit of joy we got with the brief running a couple days ago, the carb works best with 7 half turns on the main jet. Dad's recollection is it used to run somewhere between 3 and 4 half turns on the main jet. Compensation for reduced overall vacuum from the head gasket being out maybe.

I've suspected that the HEI is bad before, we have not checked the pickup, will look into that. But we have spark, it appears, which means we aren't getting fuel. However I'm finding wet plugs up there now. Nothing makes sense right now. It won't fire on ether, choke, no choke etc. Visible spark on a all 6 grounded plugs. Clean em, put em back in and no fire.

Sonny
Even if the head gasket is blown, it should still RUN, even for a bit to get it moved to somewhere less stupid for the job and get a hot compression on 5 and 6. I'm not prepared to tear down for a head gasket if there's some other issue that will still be there to fight with when it's done. Been there done that.

Dad has a timing light and a spark tester and a remote start switch hopefully with those tools we can see what's going on better with the spark.

Also I have a feeling we have two breached fuel filters one is a massive 1/2 gallon sized one with a drain, the other is a last ditch screen on the electric fuel pump. There is evidence of debris in the carb bowl even after multiple attempts to flush it. Going to try one more time before giving up on them, replacing them and cleaning the carb again.
 
IF you have fire on plugs out but not in then you have definate dist or plug problem. Junk that transistor thing and put good old points in it. Not all motors run on these things and if you had it in there for a long time----well its probably burned out by now! Is there a way to test them? I wont have them on the place, so I dont IF they can even be tested.
Also try some different plugs as a test-----soaking wet plugs wont fire under compression either, once soaked its hard to revive them but you can also take the plugs out, get them really hot with a torch then while hot put them back in as fast as you can and try that as a test. This should get you running long enough to move it to someplace else. I do that on chainsaws and tractors all the time. Todays plugs are not quality made either and very easy to short out under compression.
 
As the world turns and long story short...

The coil went out, it failed an ohm test from the discharge post to the positive and negative terminals with only 800 ohms. New (used) coil, 10k ohms. Had spark. As of the other day, it was working... Who'd of thunk it.

After that, the machine had an extreme misfire. We were thinking that the head gasket was bad and was blowing back because it still wouldn't run.

We pulled the valve cover to check for stuck valves. All looked good.

The distributor cap ended up having moisture in it. I had cleaned it out days ago with WD40 several times, but it just distributed the moisture around. Dad found a can of Mass Airflow Sensor cleaner and that did the trick to clean out the moisture.
The machine runs with a slight miss (feel it in the frame) until warm when it finally begins running on all 6. Really good power and exhaust temp. Couldn't hold my hand in front of it the other day I could albeit running okay. So we've got good fire now.

Time to put it back together and finish cleaning up the brush. We may end up doing the head gasket anyways later, but thanks a ton everyone for your help the suggestions did make a big difference.
 

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