Ericson gang:
After some prompting by members of this email list, I decided to complete a long-overdue valve adjustment on our Universal diesel. Along the way, I picked up a few bits of engine lore, reported below for the benefit of other weekend tinkerers.
We have a Universal M25XP. The Universal Engine manual is intended for trained mechanics and assumes that the reader knows more than I do. The missing bits stopped me in my tracks.
Here are my discoveries:
Cylinders are numbered from front to back with cylinder 1 being the one closest to the v-belt end of the engine.
When facing the front (v-belt end) of the engine, rotation of the crankshaft is clockwise.
Adjusting the valves involves a lot of rotating the engine by hand. Turning the engine operates the seawater pump. To avoid water-logging the muffler, I turned off the seawater valve.
I was initially concerned that the engine would be difficult to turn, but found that I could rotate it by hand by twisting the water-pump pulleys. It is probably impossible to start a diesel by hand but to be on the safe side I pulled out the engine stop. This also cuts off the fuel supply, preventing the injectors from flooding the cylinders.
The timing port which provides a view of the marks on the flywheel is located just aft of the rear engine mount on the left side (Left when viewed from the front (v-belt) end of the engine). For peering into the timing hole I used a mechanic's mirror with an adjustable handle which I was able to prop in position and a penlight clamped in my teeth. A headlamp or one of those mechanic's lights with a goose-neck and magnetic base would have been helpful.
The marks are not as described in the manual. According to the manual, there is fuel timing mark for each cylinder (labeled F1, F2 etc.) followed 25 degrees later by a top dead center mark (labeled TC1, TC2, TC3). The marks in my engine were completely different: first an unlabeled 25 degree mark, then a labeled 20 degree mark, unlabeled 15 deg., labeled 10, and labeled top dead center. The labels were in microscopic script, reversed by my mirror (which threw me for a few minutes). The top dead center label looks like "1C". I assume this is a badly printed "TC". The cylinders are not numbered on the flywheel, it was necessary to identify them by watching the operation of the valves.
Before removing the valve cover, I bought a new valve cover gasket. The guy in the shop suggested coating the groove in the cover with Vaseline to hold the gasket in place long enough to drop the cover over the engine. This worked. The old gasket was held in place on the cover by a thin coat of flexible Permatex which cleaned off without difficulty, this is an alternative.
Several times during the operation I missed the marks and had to rotate the engine while watching the rocker arms until I found the compression stroke of the cylinder that I was working on. Intake and exhaust valves can be identified by observing their proximity to the manifolds.
The engine fired up immediately. Still sounds like someone is shaking a box full of loose diesel parts but the ticking of the valve-train is quieter.
Hope someone out there finds this useful.
After some prompting by members of this email list, I decided to complete a long-overdue valve adjustment on our Universal diesel. Along the way, I picked up a few bits of engine lore, reported below for the benefit of other weekend tinkerers.
We have a Universal M25XP. The Universal Engine manual is intended for trained mechanics and assumes that the reader knows more than I do. The missing bits stopped me in my tracks.
Here are my discoveries:
Cylinders are numbered from front to back with cylinder 1 being the one closest to the v-belt end of the engine.
When facing the front (v-belt end) of the engine, rotation of the crankshaft is clockwise.
Adjusting the valves involves a lot of rotating the engine by hand. Turning the engine operates the seawater pump. To avoid water-logging the muffler, I turned off the seawater valve.
I was initially concerned that the engine would be difficult to turn, but found that I could rotate it by hand by twisting the water-pump pulleys. It is probably impossible to start a diesel by hand but to be on the safe side I pulled out the engine stop. This also cuts off the fuel supply, preventing the injectors from flooding the cylinders.
The timing port which provides a view of the marks on the flywheel is located just aft of the rear engine mount on the left side (Left when viewed from the front (v-belt) end of the engine). For peering into the timing hole I used a mechanic's mirror with an adjustable handle which I was able to prop in position and a penlight clamped in my teeth. A headlamp or one of those mechanic's lights with a goose-neck and magnetic base would have been helpful.
The marks are not as described in the manual. According to the manual, there is fuel timing mark for each cylinder (labeled F1, F2 etc.) followed 25 degrees later by a top dead center mark (labeled TC1, TC2, TC3). The marks in my engine were completely different: first an unlabeled 25 degree mark, then a labeled 20 degree mark, unlabeled 15 deg., labeled 10, and labeled top dead center. The labels were in microscopic script, reversed by my mirror (which threw me for a few minutes). The top dead center label looks like "1C". I assume this is a badly printed "TC". The cylinders are not numbered on the flywheel, it was necessary to identify them by watching the operation of the valves.
Before removing the valve cover, I bought a new valve cover gasket. The guy in the shop suggested coating the groove in the cover with Vaseline to hold the gasket in place long enough to drop the cover over the engine. This worked. The old gasket was held in place on the cover by a thin coat of flexible Permatex which cleaned off without difficulty, this is an alternative.
Several times during the operation I missed the marks and had to rotate the engine while watching the rocker arms until I found the compression stroke of the cylinder that I was working on. Intake and exhaust valves can be identified by observing their proximity to the manifolds.
The engine fired up immediately. Still sounds like someone is shaking a box full of loose diesel parts but the ticking of the valve-train is quieter.
Hope someone out there finds this useful.
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