engine dies after 2 hour run

[Anchorage Frank]

Many thanks to all who helped me with this. I seem to have found a bit of an issue at the top of the Raycor and sealed the stripped bolt there with a bit of yellow Teflon tape. Got me home after a pleasant beat out in 20 kn. (Odd, the wind dies when you run with it). Local mechanic (reached by telephone from out in the bay) said the Raycor is a frequent source of this kind of leakage.

[BonesD]

Vacuum and Vapor Lock are two separate issues. Yes, it could easily take two hours for a vacuum lock to occur. The fuller the tank the less time it should take. A vapor lock usually occurs in a specific spot in the fuel deliver line.
Working as a Porsche/Audi mechanic back in the early 70’s one of the 914 models was prone to vapor lock as the fuel lines would get hot and cause the problem. Mid engine car and everything was pretty tight. Customers would have their ride drug in on the hook only for us mechanics to go out turn the key and have the engine start and run flawlessly. It took awhile to figure that out. Meanwhile quite a few customers were unhappy that their vehicles were getting towed for the same issue.

[Hudson Force]

Originally Posted by Anchorage Frank

Many thanks to all who helped me with this. I seem to have found a bit of an issue at the top of the Raycor and sealed the stripped bolt there with a bit of yellow Teflon tape. Got me home after a pleasant beat out in 20 kn. (Odd, the wind dies when you run with it). Local mechanic (reached by telephone from out in the bay) said the Raycor is a frequent source of this kind of leakage.

Thanks for sharing the outcome. This does leave me curious though,- If you had an air pocket at the top of your Raycor how were you able to restart after a couple hours wait time without topping off the Raycor with fuel to remove the air? My system never had an ability for my Raycors to refill unless I unscrewed the tops and added diesel.

Could you have had gravity pressure from the tank that pushed the air back out? ...'but, if so, wouldn't you have had diesel fuel then seeping out of this leak when the engine is not running? Did you have an extra diesel spill or smell in your engine compartment after leaving the boat unattended? 'just a curiosity.

[Jesse Gage]

Originally Posted by Anchorage Frank

My Catalina 30 has the Universal M25 XP engine; it's been reliable for the nine years I've owned it and reasonably maintained. It starts just fine. However, in the past year it has shut off after running for two hours or so at cruising speed; I can get it started again but often after a long wait (hours or more). I've replaced the old fuel lines and filters (it has a Raycor water separator); fuel looks clean. I can't continue to rely on sailing into the harbor; the slip is four ninety degree turns away even if I have a good wind (besides, it makes the passengers nervous). Any suggestions?

if it runs on gasoline sounds like vapor lock, look for a place where fuel line to carb is heating up, and insulate it.

[Mickeyrouse]

I experienced something like this recently. After running for six hours or so the engine would lose power. I’d check the Racor filter, looking for water or a clogged filter. I’d change the filter, and re-fill the filter bowl with fresh diesel. It kept doing it. Finally determined that the fuel shut-off valve, being ancient, was leaking air in to the system. The process of checking the filter and re-filling the filter bowl was obscuring the fact that the filter bowl was essentially empty. If I had observed the the clear turbine bowl I would have caught the fine stream of air bubbles that would have revealed the problem. I needed to change the filters anyway- somewhere a load of fuel included a lot of fine storage tank rust- and a fair amount of water (bought at diesel prices).

[oplatek]

Electric fuel pump shall make ticking noise when you turn ignition on. It also have screen filter on the bottom of the body. You should also hear alarm buzzer when you turn ignition on, indicating low oil pressure, because engine is not running. How many microns is your Racor filter? 2 microns is too fine and get cloged easy. It is required for electronics injectors and I think brown in color. 30 microns is red in color and more appropriate for your engine. Secondary filter mounted on the engine stbd side is 30 microns. Obviously fuel tank vent could be an issue. Did try to prime engine ? It is easy just turn ignition on and open litle bleeding valve on the top of injector pump. Let it run for 10-20 second and close it. During that you should rear electric pump ticking.

[chasfgr]

Originally Posted by oplatek

Electric fuel pump shall make ticking noise when you turn ignition on. It also have screen filter on the bottom of the body. You should also hear alarm buzzer when you turn ignition on, indicating low oil pressure, because engine is not running. How many microns is your Racor filter? 2 microns is too fine and get cloged easy. It is required for electronics injectors and I think brown in color. 30 microns is red in color and more appropriate for your engine. Secondary filter mounted on the engine stbd side is 30 microns. Obviously fuel tank vent could be an issue. Did try to prime engine ? It is easy just turn ignition on and open litle bleeding valve on the top of injector pump. Let it run for 10-20 second and close it. During that you should rear electric pump ticking.

Some pumps click, some whir and many engines have none at all - I suspect the OP is by now totally confused.
My installation will work,with no primary pump, for the top 50% of the tank, as the tank fuel-level is then above the injector pump.
Without a detailed knowledge of engine, pump and installation, it's a case of the blind leading the blind, in blind assurance of their own omiscience.