M18 Starting Problems

[kmcconaughey]

Thanks Jim!

Here's it is:

 

[jchamberlin]

Kraig: Thank you for posting the Service Bulletin from Jim Diederichs.

Jim: Thank you for sending the Service Bulletin. And just so I'm clear, the use of Pig Putty has been authorized. (Has anyone checked with Kentucky Ken on this?

)

Joshua Stertz: Thank you again for your interest, and arousing the attention of Jim Diederichs.

By-the-way, Jim, Glenbeualh, Wisconsin couldn't be a better place to live, it seems to me. I've only traveled through Wisconsin, on my way from the city of Chicago to a friend's cabin in Iron Mountain, but I always thought the area between Fond du Lac and Sheboygan would be the perfect place to be, and there you are! As far as Google Maps goes, you live in the middle of a forest preserve.

Anyway, thanks for the help!

 

[jstertz]

Jim--Thanks for coming to the rescue with this bulletin and thanks for forwarding to our in house picture/document posting guru. I probably would've worked on it all night and still not have got it correctly uploaded.

Kraig--Thanks for always keeping the documented info in front of us!

Jeremiah--Looks like you at least have had time to think through a plan of attack. It is really hard to take a step or two backward in order to take some forward!! But like you said, thankfully you don't need to be ready for major snow removal in just a few weeks to a month like us up in the "Frozen Chosen" of the north. I hope that you can catch some positive breaks on this dude finally.

 

[jdiederichs]

Since the location of the case crack is not through an oil passage the case is merely an enclosure at that point, so yes, I would certainly prep the area well and apply the designated "mud" to rescue this engine. Considering the high cost of a short block (>$2000)I see nothing wrong with mending this case, do you?

No thanks necessary regarding the information posted, just one Cub enthusiast help others, like we all do. Each of us is in a unique position to help each other.

 

[kmcconaughey]

Jim, this statement:

<blockquote><hr size=0><!-quote-!><font size=1>quote:</font>

No thanks necessary regarding the information posted, just one Cub enthusiast help others, like we all do. Each of us is in a unique position to help each other.<!-/quote-!><hr size=0></blockquote>

<font size="-1">I believe perfectly describes why this forum is the best!</font>

 

[jchamberlin]

All: Off-hand I would say that the governor shaft shifted a bit, it is definitely not set into the block 0.285" (7.1mm), nor is it pinned.

I guess they didn't get Service Bulletin 246.

 

[jchamberlin]

The finish up this thread, the reason Service Bulletin was written, the reason the flywheel key let go, and why I couldn't control the RPMs, and ultimately the reason I couldn't start my M18 to begin with:

When the engine "overheated" the pressed-in Governor shaft backed out and the Governor itself fell into the engine:

One of the weights was separated from its spindle:

This evidently happened when the weight came into contact with the connecting rod for the #1 piston, the one nearest the flywheel on the left side of the engine (facing the tractor), just below where the governor is mounted on the engine.

The contact appeared to occur when the rod passed closest to the left side of the block (Side #1) and was responsible for the damage as seen from the outside which I posted earlier, now seen from the inside:

Everything appeared to have occurred as the crank pin was moving upward in an clockwise rotatation, as viewed from the front of the tractor, PTO side of the engine.

Despite Jim Diederichs' assurances, I don't feel confident putting "Pig Putty" over a crack this large and so near the mounting for the cylinder barrels. Neither am I convinced that welding the aluminum is going to yield a "good" part, I'm afraid the aluminum will warp in unforeseen ways. In either case, the risk of further damage appears too great to me.

Thanks to a fellow Cub enthusiast, I have located a replacement block for a reasonable price. The other parts, with the possible exception of the #1 connecting rod appear to be OK, including especially the pistons and the cylinder bores. I will post detailed photos of the tear-down on a different thread, since I would appreciate expert (and amateur) assessment of the wear patterns before I make a final determination.

 

[jdiederichs]

Jeremiah,

After seeing it with the cylinder barrel removed, as well as the view fom the interior, I heartily agree, do NOT re-use that crank case. The earlier pics showed only some exterior shots that did not show the extent of damage.

 

[aaytay]

Jeremiah-
I'm sorry to read about the (mis)adventures you had with this engine. I think you're correct in replacing the engine case on this one.

After reading all of this, I think I'm going to take the time to finally do the roll-pin mod to my 2 Magnum engines.

Please do follow up with posts on the tear-down and subsequent rebuild. None of use ever WANT to go through something like this, but your experience will certainly help us all!

 

[nbartee]

Thanks a bunch Kraig, for posting service bulletin 246. I never knew what they meant by staking the governor shaft. Now I can do my engine.

 

[jdiederichs]

Norm,
Look at the release date of that bulletin,4/98. You would have thought many more Magnums would have already been pinned. All those that aren't are definitely needing to be done.

Jeremiah's bad experience is reason enough to take the time and do it guys. It's sort of like the balance gear issue in the singles, a ticking timebomb.

 

[nbartee]

Jim,

Yes, you would think. I have a KT17 and three M18's and none are staked. I wonder, after they are staked, you won't be able to remove that shaft. I guess they don't wear, so it's not a problem.