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Recently, I started a thread about my K28 running stiffly in reverse and what I did to fix it. There was no single set of directions for me to follow in setting the valve timing. I used the gear setting write-up in the Roundhouse web site and got help from posts by Jay Kovac and the Bednariks. Now that I've been through the drill, I thought it might be helpful to others who may have to time their engines if I turned what I did into a photo essay. I expect that what I have here would also apply to a K27 and to the K36 (when it comes out).
I eventually found three problems with my loco which had to be corrected. First, the J-bar was not zeroed. Second, eccentric crank on the engineer's side was not set at the correct angle. Third, the valve on the engineer's side was not positioned correctly on its rod.
The J-bar problem was my fault and resulted from adjusting the R/C servo incorrectly when I installed the R/C. Once I had readjusted the servo, the linkage moved equally far up and down from the neutral position when I commanded the loco to forward or reverse. If you are using the manual J-bar, it can be centered by loosening the screws that hold the stand in the cab and sliding it backward or forward until the neutral position really is neutral.
In order to make adjustments to the valves, you have to open up the steam chests. To do that, you have to loosen or remove some details. All of the operations can be done using the nut drivers and allen wrenches provided with the loco (except for one place I'll point out shortly).
First, remove the four miniature hex head bolts which hold the forward running boards in place. You do not need to remove the running boards. You just need to be able to move them to get at other parts.
Next, you need to loosen the set screws in the dummy steam pipes.
Now, remove the row of four hex bolts which attach the wrappers to the cylinders.
Finally, carefully pull the wrappers off of the cylinders. You will need to move the running boards some and the dummy steam pipes and the wrappers will separate from one another. A lip near the back of the wrapper will likely snag details such as pipes. Just be gentle and you can wiggle the wrappers free.
With the wrappers off, you can open the steam chest. This is the only place the Accucraft tools did not apply. I used a 5/32" nut driver (very close to 3mm).
Slide the cover up off the threaded studs and you are ready to begin timing. One caution, on my engine, two of the studs unscrewed partially from the cylinder and their shoulders kept the lid from seating all of the way down at reassembly. Before you put your loco back together, be sure that the studs are screwed in and that their shoulders are below the surrounding surface.
I'm going to break now to post this much and will follow up shortly with more posts to complete the timing process.
I eventually found three problems with my loco which had to be corrected. First, the J-bar was not zeroed. Second, eccentric crank on the engineer's side was not set at the correct angle. Third, the valve on the engineer's side was not positioned correctly on its rod.
The J-bar problem was my fault and resulted from adjusting the R/C servo incorrectly when I installed the R/C. Once I had readjusted the servo, the linkage moved equally far up and down from the neutral position when I commanded the loco to forward or reverse. If you are using the manual J-bar, it can be centered by loosening the screws that hold the stand in the cab and sliding it backward or forward until the neutral position really is neutral.
In order to make adjustments to the valves, you have to open up the steam chests. To do that, you have to loosen or remove some details. All of the operations can be done using the nut drivers and allen wrenches provided with the loco (except for one place I'll point out shortly).
First, remove the four miniature hex head bolts which hold the forward running boards in place. You do not need to remove the running boards. You just need to be able to move them to get at other parts.

Next, you need to loosen the set screws in the dummy steam pipes.

Now, remove the row of four hex bolts which attach the wrappers to the cylinders.

Finally, carefully pull the wrappers off of the cylinders. You will need to move the running boards some and the dummy steam pipes and the wrappers will separate from one another. A lip near the back of the wrapper will likely snag details such as pipes. Just be gentle and you can wiggle the wrappers free.
With the wrappers off, you can open the steam chest. This is the only place the Accucraft tools did not apply. I used a 5/32" nut driver (very close to 3mm).

Slide the cover up off the threaded studs and you are ready to begin timing. One caution, on my engine, two of the studs unscrewed partially from the cylinder and their shoulders kept the lid from seating all of the way down at reassembly. Before you put your loco back together, be sure that the studs are screwed in and that their shoulders are below the surrounding surface.
I'm going to break now to post this much and will follow up shortly with more posts to complete the timing process.