Help! 2072 that cranks really hard!

[rcahoy]

Rebuilt a 2072 with a Mag 20 and now it cranks over really really hard. Turning the driveshaft by hand is impossible. Only way is to use a pipe wrench on driveshaft. WTH? Replaced battery and solenoid, and it still acts like the solenoid is bad, clicking. Have had it running before, but not sure why this problem now? Should I remove spark plugs and try turning over to see if maybe it's a stuck valve? Double checked all the electrical connections and they are tight. Even ran a separate ground cable to motor to make sure it was properly grounded. The positive cable going down to starter seems to get pretty hot when trying to start also.

One of you probably know exactly what the issue is.

 

[mgonitzke]

Is there a PTO clutch installed? If so, will it turn over normally with the PTO clutch removed? If the bearing in the clutch seizes, it may make the engine difficult to turn over, but the bearing failure usually provides hours of warning in the form of a squealy bearing when the clutch is off.

If not, it seems likely there is something very, very wrong with engine, internally. When you say "rebuilt", what does that mean? Not much for service parts for the M20 available. How many hours since the "rebuild"?

The hot starter cable is from the starter being stalled because it can't turn the engine over.

 

[mfrade]

I'd agree with Matt. If it's completely assembled, start removing "driven" systems to see if the load changes, like the PTO belt and / or the driveshaft. Remove 1 at a time and see if the engine turns easier each time. If it doesn't get any easier, perhaps something inside the motor isn't right.

 

[rfunk]

Just redid the K321 in my CC149. Advice and manual are repetitively emphatic about making sure the con rod and cap are aligned correctly. Could an error like that be binding up the rod on the crank? Maybe debris got into one of the crank bearings? Either way, if you did get it to start with major internal difficulties, it would probably "hatch" within minutes, or even seconds. Yeah, you probably will have to pull it apart again - but at this point, costing you more time, hopefully not a huge pile of $$. Hope it's not internal, I like Mike Frade's methodology above.

 

[mgonitzke]

Just redid the K321 in my CC149. Advice and manual are repetitively emphatic about making sure the con rod and cap are aligned correctly. Could an error like that be binding up the rod on the crank? Maybe debris got into one of the crank bearings?

Unfortunately I think those are two of the more likely possibilities if it is an internal problem.

I got my 782 with a blown engine. Someone had rebuilt the KT-17 Series II but had used FAR too much RTV on the case halves (another thing the manual for the engine in question is VERY emphatic about) and a glob of it ended up lodged in the crank oil galleries and starved one of the rods for oil, and it threw it out the top of the block.

 

[glippert]

I recently replaced pistons & rings in a 1250 and a 1650, and I noticed the emphasis on proper orientation of the piston, rod, and cap. I did them as the manual directed, but wondered what the effect would be if any of those parts were installed incorrectly. The manual was very emphatic about the the potential for serious damage, but not very specific as to what that damage might include. Has anyone here made that mistake (and are willing to admit it)? Curious minds want to know...

 

[mgonitzke]

I recently replaced pistons & rings in a 1250 and a 1650, and I noticed the emphasis on proper orientation of the piston, rod, and cap. I did them as the manual directed, but wondered what the effect would be if any of those parts were installed incorrectly. The manual was very emphatic about the the potential for serious damage, but not very specific as to what that damage might include. Has anyone here made that mistake (and are willing to admit it)? Curious minds want to know...

Not entirely applicable in the OP's case since the M20 is pressure lube, but if you put the rod cap on bassackwards on a K-series, it will not get oil thrown off the cam and will probably starve the rod for oil and seize or throw the rod.

The danger in either case is that the crank end of the rod is bored with the rod cap in a certain orientation, and if it if flipped around, it may not match exactly if the bore for the crankpin is not centered exactly between the rod cap bolts, which will make the rod too tight on the crank if the cap is installed backwards, and could cause the engine to seize.

 

[glippert]

Great explanation - thanks, Matt! That's the kind of knowledge sharing that makes this forum so great.

 

[rcahoy]

Thanks guys. Turns out the PTO was not properly installed and binding on the crankshaft. Removed PTO and started like a champ. Thankful nothing technically wrong with the engine.

Now the PS pump is pushing oil up and out of the steering column. The seals must have dried up. Sitting for about 2 years. Any chance after running it a while that they'll lubricate up and stop leaking?

Any on top of that, the linkage must not be quite right as it's pretty herky, jerky, or possibly the hydro pump has just not lost all the air from the system yet.

 

[mfrade]

Good to hear it was only the PTO causing the issue.
Any chance on the seals??? I think you have 2... slim and none.. just my opinion.. leaks don't "fix themselves"..

Herky Jerky.. could be a few things causing that. When was the last fluid and filter change?

 

[mgonitzke]

Your steering column face seal is bad. They eventually all do that. The rebuild kit has an improved seal that shouldn't do it again. Rebuild kit is available several places. When I did mine, the JD kit was the cheapest. Here is a link to the service instructions for the steering column. I would also get the spring kit and replace those while you have it apart.

Parker HGF Steering Column Service Instructions

 

[rfunk]

Great to hear that it was external to the engine. So glad you didn't make the mistake of opening it up before you checked the externals!! My experience, you feel like an a** when you do that.

 

[rcahoy]

Anyone have any suggestions how to fix the herky jerky hydrostatic drive on a 2072? Just seems extremely touchy and not smooth like my other Cubs. Perhaps a link somewhere on this forum that has addressed this already? I can’t seem to find it.

 

[dschwandt]

That link should be a "sticky" in the manual section of this site.

 

[rcahoy]

Spent about a half hour searching for "Sticky" in manual with no luck. Maybe I missed it. Why is it so hard to find stuff on this forum? I apparently don't know the easy way!

 

[kmcconaughey]

The "Sticky" is actually a thread that is "pinned" to stay at the top of the page in the "IH Cub Cadet Tractor Forum"

Here's where the manuals can be found:

Cub Cadet Manuals

The issue you are having with your 2072 is likely a worn "trunion" which is part of the mechanism in the hydro control. Here's a link to the CubFAQ with some info on how to repair it on an IH built Cub Cadet.

CubFAQ #33 How do I repair my Trunion on my Hydro?

 

[rcahoy]

Perfect! Thanks Kraig and Dave. You two always come through!